Relevant bibliographies by topics / Mutant Phenotype

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Academic literature on the topic 'Mutant Phenotype'

Author: Grafiati
Published: 6 September 2023

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Journal articles on the topic "Mutant Phenotype"

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von Eiff, Christof, Peter McNamara, Karsten Becker, Donna Bates, Xiang-He Lei, Michael Ziman, Barry R. Bochner, Georg Peters, and Richard A. Proctor. "Phenotype Microarray Profiling of Staphylococcus aureus menD and hemB Mutants with the Small-Colony-Variant Phenotype." Journal of Bacteriology 188, no. 2 (January 15, 2006): 687–93. http://dx.doi.org/10.1128/jb.188.2.687-693.2006.

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ABSTRACT Standard biochemical tests have revealed that hemin and menadione auxotrophic Staphylococcus aureus small-colony variants (SCVs) exhibit multiple phenotypic changes. To provide a more complete analysis of the SCV phenotype, two genetically defined mutants with a stable SCV phenotype were comprehensively tested. These mutants, generated via mutations in menD or hemB that yielded menadione and hemin auxotrophs, were subjected to phenotype microarray (PM) analysis of over 1,500 phenotypes (including utilization of different carbon, nitrogen, phosphate, and sulfur sources; growth stimulation or inhibition by amino acids and other nutrients, osmolytes, and metabolic inhibitors; and susceptibility to antibiotics). Compared to parent strain COL, the hemB mutant was defective in utilization of a variety of carbon sources, including Krebs cycle intermediates and compounds that ultimately generate ATP via electron transport. The phenotype of the menD mutant was similar to that of the hemB mutant, but the defects in carbon metabolism were more pronounced than those seen with the hemB mutant. In both mutant strains, hexose phosphates and other carbohydrates that provide ATP in the absence of electron transport stimulated growth. Other phenotypes of SCV mutants, such as hypersensitivity to sodium selenite, sodium tellurite, and sodium nitrite, were also uncovered by the PM analysis. Key results of the PM analysis were confirmed in independent growth studies and by using Etest strips for susceptibility testing. PM technology is a new and efficient technology for assessing cellular phenotypes in S. aureus.
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McKenzie, Calen, Ivette Guzman, Ciro Velasco-Cruz, and Paul W. Bosland. "Photosynthetic Pigments Profiled in Capsicum Lutescens Mutants." Journal of the American Society for Horticultural Science 146, no. 4 (July 2021): 233–40. http://dx.doi.org/10.21273/jashs05025-20.

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Lutescens, or lutescent, plant mutants produce leaves that are abnormally light yellow-green compared with normal plants, and are observed in multiple species of Capsicum as well as other genera such as Zea, Oryza, and Oenothera. Previous investigations into the lutescent phenotype in Capsicum have focused on genetic and transcriptomic analyses, and comparatively little is known about the phytochemical constituents of the lutescent leaf phenotype. Previous research in similar lutescent mutants in Capsicum and Oryza species has attributed their pale yellow-green leaf color and poor vigor to deficient chloroplast development. A total of 25 accessions of Capsicum lutescens mutants were phenotyped and analyzed based on a multivariate approach, using ‘Jupiter’ bell pepper (Capsicum annuum) with normal green leaves as a contextual benchmark. Photosynthetic pigments from mutant leaves were extracted and analyzed using high-performance liquid chromatography (HPLC); reflectance of the leaf material was measured with a chromameter using the L*a*b* color space. The chlorophyll a (Chl a)/b (Chl b) ratio was greater in leaves of lutescens mutants than in ‘Jupiter’. Multivariate statistical analyses revealed all lutescent mutant accessions could be distinguished from the ‘Jupiter’ contextual benchmark by variables indicating poor chloroplast development and increased photooxidative stress in lutescent mutant accessions. The lutescent leaf phenotype was not found to be caused by elevated xanthophyll or decreased chlorophyll concentrations. Furthermore, multivariate analysis revealed the lutescent mutant phenotype to be variable, with a wide range of phenotypes clustered into four major groups.
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Alvarez-Ortega, Carolina, Irith Wiegand, Jorge Olivares, Robert E. W. Hancock, and José Luis Martínez. "Genetic Determinants Involved in the Susceptibility of Pseudomonas aeruginosa to β-Lactam Antibiotics." Antimicrobial Agents and Chemotherapy 54, no. 10 (August 2, 2010): 4159–67. http://dx.doi.org/10.1128/aac.00257-10.

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ABSTRACT The resistome of P. aeruginosa for three β-lactam antibiotics, namely, ceftazidime, imipenem, and meropenem, was deciphered by screening a comprehensive PA14 mutant library for mutants with increased or reduced susceptibility to these antimicrobials. Confirmation of the phenotypes of all selected mutants was performed by Etest. Of the total of 78 confirmed mutants, 41 demonstrated a reduced susceptibility phenotype and 37 a supersusceptibility (i.e., altered intrinsic resistance) phenotype, with 6 mutants demonstrating a mixed phenotype, depending on the antibiotic. Only three mutants demonstrated reduced (PA0908) or increased (glnK and ftsK) susceptibility to all three antibiotics. Overall, the mutant profiles of susceptibility suggested distinct mechanisms of action and resistance for the three antibiotics despite their similar structures. More detailed analysis indicated important roles for novel and known β-lactamase regulatory genes, for genes with likely involvement in barrier function, and for a range of regulators of alginate biosynthesis.
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Yu, I.-ching, Kevin A. Fengler, Steven J. Clough, and Andrew F. Bent. "Identification of Arabidopsis Mutants Exhibiting an Altered Hypersensitive Response in Gene-for-Gene Disease Resistance." Molecular Plant-Microbe Interactions® 13, no. 3 (March 2000): 277–86. http://dx.doi.org/10.1094/mpmi.2000.13.3.277.

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A mutational study was carried out to isolate Arabidopsis thaliana plants that exhibit full or partial disruption of the RPS2-mediated hypersensitive response (HR) to Pseudomonas syringae that express avrRpt2. Five classes of mutants were identified including mutations at RPS2, dnd mutations causing a “defense, no death” loss-of-HR phenotype, a lesion-mimic mutant that also exhibited an HR¯phenotype, and a number of intermediate or partial-loss-of-HR mutants. Surprisingly, many of these mutants displayed elevated resistance to virulent P. syringae and, in some cases, to Peronospora parasitica. Constitutively elevated levels of pathogenesis-related (PR) gene expression and salicylic acid were also observed. In the lesion-mimic mutant, appearance of elevated resistance was temporally correlated with appearance of lesions. For one of the intermediate lines, resistance was shown to be dependent on elevated levels of salicylic acid. A new locus was identified and named IHR1, after the mutant phenotype of “intermediate HR.” Genetic analysis of the intermediate-HR plant lines was difficult due to uncertainties in distinguishing the partial/intermediate mutant phenotypes from wild type. Despite this difficulty, the intermediate-HR mutants remain of interest because they reveal potential new defense-related loci and because many of these lines exhibit partially elevated disease resistance without dwarfing or other apparent growth defects.
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Zhang, Xingping, Bill Rhodes, Vance Baird, and Halina Skorupska. "A Tendrilless Mutant in Watermelon: Phenotype and Development." HortScience 31, no. 4 (August 1996): 602e—602. http://dx.doi.org/10.21273/hortsci.31.4.602e.

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A spontaneous watermelon mutant, previously named branch less, was re-evaluated in this study. The mutant watermelon plants from genetic stock Bl-91 and derived from F2 and BC1 populations, did not produce tendrils under field or greenhouse conditions. The mutants stopped producing branches after the fifth or sixth node. Leaf shape changed during development of the mutants. Early leaves were normal, but later leaves had fewer and fewer lobes, finally becoming triangular toward the end of the shoot. The most distinct effect of the mutant gene was to convert vegetative meristems into floral meristems; tendrils and axillary buds were replaced by flowers at the node. The mutant plants were determinate. A grafting experiment showed that the rootstock had no effect on the mutant phenotype. Genetic analysis of F1, F2, and BC1 populations suggested that the mutant is inherited as a single, recessive nuclear gene. Based on the phenotype, a new name is suggested for this mutant: tendrilless, with a new gene symbol tl.
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Waddell, D. R., K. Duffy, and G. Vogel. "Cytokinesis is defective in Dictyostelium mutants with altered phagocytic recognition, adhesion, and vegetative cell cohesion properties." Journal of Cell Biology 105, no. 5 (November 1, 1987): 2293–300. http://dx.doi.org/10.1083/jcb.105.5.2293.

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Mutants that have been selected for defects in phagocytic recognition, adhesion, and vegetative cell-cell cohesion were found to be larger and more highly multinucleate than their parent strain. This defect is associated with the complex mutant phenotype of these mutants since revertants of the mutants coordinately acquire the wild-type phenotype for all of the defects. The larger size and multinuclearity were due to a high frequency of failure of cytokinesis in cells of wild-type size. This was shown by purifying the small cells in mutant populations and observing their growth and cell division. The mutant phenotype is more penetrant during axenic growth. Most of the mutants are not multinucleate when grown on bacteria. Recently, new mutants have been isolated that are also multinucleate when grown on bacteria by a strong selection procedure for non-adhesion to tissue culture dishes. The pleiotropic mutant phenotype and the greater penetrance of the mutant phenotype in axenic culture can be explained by hypothesizing a deficiency in a membrane component of the actomyosin motor that is involved in all of the processes defective in the mutants.
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DeLaurier, April, Douglas G. Howe, Leyla Ruzicka, Adam N. Carte, Lacie Mishoe Hernandez, Kali J. Wiggins, Mika M. Gallati, et al. "ZebraShare: a new venue for rapid dissemination of zebrafish mutant data." PeerJ 9 (April 13, 2021): e11007. http://dx.doi.org/10.7717/peerj.11007.

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Background In the past decade, the zebrafish community has widely embraced targeted mutagenesis technologies, resulting in an abundance of mutant lines. While many lines have proven to be useful for investigating gene function, many have also shown no apparent phenotype, or phenotypes not of interest to the originating lab. In order for labs to document and share information about these lines, we have created ZebraShare as a new resource offered within ZFIN. Methods ZebraShare involves a form-based submission process generated by ZFIN. The ZebraShare interface (https://zfin.org/action/zebrashare) can be accessed on ZFIN under “Submit Data”. Users download the Submission Workbook and complete the required fields, then submit the completed workbook with associated images and captions, generating a new ZFIN publication record. ZFIN curators add the submitted phenotype and mutant information to the ZFIN database, provide mapping information about mutations, and cross reference this information across the appropriate ZFIN databases. We present here examples of ZebraShare submissions, including phf21aa, kdm1a, ctnnd1, snu13a, and snu13b mutant lines. Results Users can find ZebraShare submissions by searching ZFIN for specific alleles or line designations, just as for alleles submitted through the normal process. We present several potential examples of submission types to ZebraShare including a phenotypic mutants, mildly phenotypic, and early lethal mutants. Mutants for kdm1a show no apparent skeletal phenotype, and phf21aa mutants show only a mild skeletal phenotype, yet these genes have specific human disease relevance and therefore may be useful for further studies. The p120-catenin encoding gene, ctnnd1, was knocked out to investigate a potential role in brain development or function. The homozygous ctnnd1 mutant disintegrates during early somitogenesis and the heterozygote has localized defects, revealing vital roles in early development. Two snu13 genes were knocked out to investigate a role in muscle formation. The snu13a;snu13b double mutant has an early embryonic lethal phenotype, potentially related to a proposed role in the core splicing complex. In each example, the mutants submitted to ZebraShare display phenotypes that are not ideally suited to their originating lab’s project directions but may be of great relevance to other researchers. Conclusion ZebraShare provides an opportunity for researchers to directly share information about mutant lines within ZFIN, which is widely used by the community as a central database of information about zebrafish lines. Submissions of alleles with a phenotypic or unexpected phenotypes is encouraged to promote collaborations, disseminate lines, reduce redundancy of effort and to promote efficient use of time and resources. We anticipate that as submissions to ZebraShare increase, they will help build an ultimately more complete picture of zebrafish genetics and development.
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Larsson, Annika Sundås, Katarina Landberg, and D. R. Meeks-Wagner. "The TERMINAL FLOWER2 (TFL2) Gene Controls the Reproductive Transition and Meristem Identity in Arabidopsis thaliana." Genetics 149, no. 2 (June 1, 1998): 597–605. http://dx.doi.org/10.1093/genetics/149.2.597.

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Abstract A new mutant of Arabidopsis thaliana that initiates flowering early and terminates the inflorescence with floral structures has been identified and named terminal flower2 (tfl2). While these phenotypes are similar to that of the terminal flower1 (tfl1) mutant, tfl2 mutant plants are also dwarfed in appearance, have reduced photoperiod sensitivity and have a more variable terminal flower structure. Under long-day and short-day growth conditions tfl1 tfl2 double mutants terminate the inflorescence without development of lateral flowers; thus, unlike tfl1 single mutants the double mutant inflorescence morphology is not affected by day length. The enhanced phenotype of the double mutant suggests that TFL2 acts in a developmental pathway distinct from TFL1. The complex nature of the tfl2 single mutant phenotype suggests that TFL2 has a regulatory role more global than that of TFL1. Double mutant analysis of tfl2 in combination with mutant alleles of the floral meristem identity genes LEAFY and APETALA1 demonstrates that TFL2 function influences developmental processes controlled by APETALA1, but not those regulated by LEAFY. Thus, the TFL2 gene product appears to have a dual role in regulating meristem activity, one being to regulate the meristem response to light signals affecting the development of the plant and the other being the maintenance of inflorescence meristem identity.
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Koerniati, Sri. "UNTAGGED MUTATION IN RICE GAL4/VP16 TRANSCRIPTIONAL ACTIVATOR FACILITATED-ENHANCER TRAP LINES." Indonesian Journal of Agricultural Science 14, no. 1 (April 21, 2013): 27. http://dx.doi.org/10.21082/ijas.v14n1.2013.27-35.

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An enhancer trap system is an insertional mutagenesis based upon gene expression, instead of gene knock-out, so its insertion in genome is expected not linked to any dramatic changes in plant phenotypes. Gene knock-out, leading to lossof- function (LoF) mutation, is a dominant approach for rice functional genomic studies. The objective of this study was to find out whether Transcriptional Activator-Facilitated Enhancer Trap (TAFET) T-DNA insertion inducing mutant phenotypes in rice TAFET population. Materials used in this experiment were T1 generation of 270 rice TAFET lines. Eight plants of each were grown in the greenhouse and observed for any mutant phenotypes. Phenotypic, histochemical, Southern<br />blot analyses were carried out to define a mutant of pSKC66.1- 8e. Result showed that about 10% of the 270 lines produced chlorophyll-deficient leaves, ranged from yellowish green (viridis), white stripe green zebra-like stripe) to completely white (albino). Albino plants died after two weeks, whilst white stripe or viridis mutants became normal in the next generation<br />(T2). Another mutant was pSKC66.1-8e line which had floral dramatic phenotype change with various spikelet shapes and number of organs, and had a single twisted culm. The flower of mutant also had gus gene expression. Plants with wild type did not express gus gene and had six or more straight culms. Molecular, histochemical and phenotypic analyses of this particular line for three generations indicated that mutant phenotype was not due to the T-DNA insertion. Since there was approved that Tos17 is activated during tissue culture and induced mutant phenotype, this line might relate to Tos17 insertion, but it needs further investigation to gain such conclusion.
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Koerniati, Sri. "UNTAGGED MUTATION IN RICE GAL4/VP16 TRANSCRIPTIONAL ACTIVATOR FACILITATED-ENHANCER TRAP LINES." Indonesian Journal of Agricultural Science 14, no. 1 (April 21, 2013): 27. http://dx.doi.org/10.21082/ijas.v14n1.2013.p27-35.

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An enhancer trap system is an insertional mutagenesis based upon gene expression, instead of gene knock-out, so its insertion in genome is expected not linked to any dramatic changes in plant phenotypes. Gene knock-out, leading to lossof- function (LoF) mutation, is a dominant approach for rice functional genomic studies. The objective of this study was to find out whether Transcriptional Activator-Facilitated Enhancer Trap (TAFET) T-DNA insertion inducing mutant phenotypes in rice TAFET population. Materials used in this experiment were T1 generation of 270 rice TAFET lines. Eight plants of each were grown in the greenhouse and observed for any mutant phenotypes. Phenotypic, histochemical, Southern<br />blot analyses were carried out to define a mutant of pSKC66.1- 8e. Result showed that about 10% of the 270 lines produced chlorophyll-deficient leaves, ranged from yellowish green (viridis), white stripe green zebra-like stripe) to completely white (albino). Albino plants died after two weeks, whilst white stripe or viridis mutants became normal in the next generation<br />(T2). Another mutant was pSKC66.1-8e line which had floral dramatic phenotype change with various spikelet shapes and number of organs, and had a single twisted culm. The flower of mutant also had gus gene expression. Plants with wild type did not express gus gene and had six or more straight culms. Molecular, histochemical and phenotypic analyses of this particular line for three generations indicated that mutant phenotype was not due to the T-DNA insertion. Since there was approved that Tos17 is activated during tissue culture and induced mutant phenotype, this line might relate to Tos17 insertion, but it needs further investigation to gain such conclusion.
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Dissertations / Theses on the topic "Mutant Phenotype"

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Sofia, Francesca. "Emx1 null mutant mouse phenotype : potential implications for human epilepsy." Thesis, Open University, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.251365.

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Rejeski, Kai Dannebom [Verfasser], and Michael [Akademischer Betreuer] Lübbert. "Elucidation of a hypersplicing phenotype in SRSF2 mutant myeloid malignancy." Freiburg : Universität, 2021. http://d-nb.info/1236500849/34.

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Morrison, Gillian M. "Analysis of the pulmonary inflammatory phenotype of the CF mutant mouse." Thesis, University of Edinburgh, 1999. http://hdl.handle.net/1842/22507.

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Studies using isolated alveolar macrophages, led to the hypothesis that the pulmonary inflammatory cells of the Cftrtm1HGU mouse function normally when given a direct inflammatory stimulus and that another aspect of the host defence system is not functioning adequately to deal with repeated exposure to low level non-specific bacteria. Recent studies on the human airway defensin molecule, hBD-1, reveal that its bactericidal properties are inactivated by high salt concentrations. It is possible that the airway surface fluid of CF patients has a raised NaCl concentration and relates to a defective host defence system caused by the CFTR mutation. This thesis describes the identification and characterisation of a mouse β-defensin gene, Defb1, sometimes referred to as mBD-1, which was shown to be homologous to the human airway beta defensin hBD-1. It was found that Defb1 was expressed in a variety of tissues including the airways and like hBD-1 is not upregulated by LPS. A genomic targeting vector was constructed and Defb1 successfully knocked out in the mouse. This study also led to the isolation of a 150kb BAC contig which was shown to contain members of both the alpha and beta defensin gene families. Using low stringency hybridisation a novel murine beta defensin gene was identified which is not highly expressed in the airways under normal conditions although it appears to be weakly upregulated by LPS. A second human beta defensin gene, hBD-2, was recently identified which was shown to be upregulated in the airways by inflammatory stimuli, thus this novel murine gene is similar to hBD-2 both in structure and function. It is hoped that the study of the murine beta defensin gene family will lead to a clearer understanding of the normal function of defensins as well as of the consequences of their dysfunction in CF.
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Benn, Caroline Louise. "Targeting mutant huntingtin to the nucleus accelerates phenotype onset in transgenic mice." Thesis, King's College London (University of London), 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.401268.

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Donzelli, A. "BEHAVIOURAL PHENOTYPE AND ELECTROENCEPHALOGRAPHIC PROFILE OF ADOLESCENT AND ADULT SNAP-25+/- MUTANT MICE." Doctoral thesis, Università degli Studi di Milano, 2013. http://hdl.handle.net/2434/214980.

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Synaptosomal-associated protein of 25 kDa (SNAP-25) is a protein that participates in the regulation of synaptic vesicle exocytosis through the formation of the soluble N-ethylmaleimide-sensitive proteine (NSF) attachment protein receptor complex and modulates voltage-gated calcium channels activity. Snap25 gene has been associated with schizophrenia, and bipolar disorder, and lower levels of SNAP-25 have been described in patients with schizophrenia. In particular several SNAP-25 intronic single polymorphisms were linked to attention deficit hyperactivity disorder, one of the most common neuropsychiatric diseases among children and adolescents. The most animal models of this pathology, available until now, are characterized by reduced SNAP-25 level in the CNS: the coloboma mice, and the spontaneously hypertensive rats (SHR). However none of them can completely ricapitulate all the core features of the human patology. Thus we used adult SNAP-25 heterozygous (SNAP-25+/−) mice in comparison with age-matched wild type mice (SNAP-25+/+) to investigate at which extent the reduction of the protein levels affects neuronal network function and mouse behavior, and the possible therapeutic effect of antiepileptic drugs. We also characterized adolescent SNAP-25+/- mice (6-7 weeks) in order to evaluate if they can be considered a new ADHD animal model. Firstly we analysed general health, sensory and motor abilities, and emotional behaviour in our animals, without finding any abnormalities in heterozygous mice. Since altered SNAP-25 level were associated with cognitive deficit, we performed T-maze test for the evaluation of spatial memory, latent inhibition test for attention, conditioned taste aversion and object recognition for associative memory. SNAP-25+/- resulted impaired in associative but not in spatial memory, probably because of the heterogeneous protein expression levels in different hippocampal areas, being more expressed in CA3, known to play a key role in associative memory, than in CA1, critical for long-term spatial memory. SNAP-25+/- has been associated to disease characterized by altered social behaviour, such as schizophrenia and bipolar disorder. We tested SNAP-25 mutant mice in sociability and social novelty test. Heterozygous showed impairment both in sociability and in social recognition. Pathologies characterized by SNAP-25 alterations show significantly higher incidence of epilepsy. For this reason we recorded the cortical electric activity of mice and we found that SNAP-25 levels reduction was associated with network hyperexcitability, in terms of spike activity, which did not lead to spontaneous epileptiform behaviour. Acute treatment with antiepileptic drugs and Ca2+ antagonist normalized cerebral activity. Among these drugs, sodium valproate was more effective in blocking EEG and behavioural deficits. Since it is known the correlation between EEG alteration and cognitive deficits we can hypothesize that the mnemonic and social deficit are due to the abnormal EEG profile. Adolescents SNAP-25+/- mice showed the same deficits found in the adults. They also were hyperactivite, and were not susceptible to d-amphetamine treatment. These results are in line with the characteristic phenotype of ADHD children, that display cognitive deficits, problems in socialization and hyperactivity, normalized by stimulants. Recently EEG analysis was used as diagnostic tool to discriminate ADHD from other neuropsychiatric diseases. EEG in ADHD children is characterized by spikes and alteration in spectral power bands frequency. Spectral analysis heterozygous mice EEG recordings was caharacterized by spikes, a decrease in fast waves and a parallel increase in slow waves, as occur in ADHD children. Repeated exposition to a VLP solution (0.1%) reduced all the behavioural deficit and was effective in blocking spike activity for two weeks, when discontinued. SNAP-25+/- mice seem to be a promising ADHD animal model, able to recapitulate almost all the core symptoms of the human disease. Repeated treatment with VLP resulted effective in all the tests carried out in adolescents mice, in line with recent findings of its therapeutic effects on ADHD symptoms in x-fragile syndrome.
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Jolivet, Katell. "Cloning and characterisation of LDW1, an Arabidopsis thaliana mutant displaying a lesion-mimic, dwarf phenotype." Thesis, Imperial College London, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.405621.

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Skowrońska, Anna Maria. "ATM mutant cellular phenotype in B-cell chronic lymphocytic leukaemia : clinical consequences and therapeutic implications." Thesis, University of Birmingham, 2013. http://etheses.bham.ac.uk//id/eprint/4720/.

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ATM germ-line mutations have been identified in a proportion of patients with chronic lymphocytic leukaemia (CLL) but their role in the development of this tumour remains unknown. In the course of this study it was established that ATM pathogenic mutations were increased among patients with chromosome 11q deletion/loss of one ATM allele when compared to healthy control individuals but not in those who did not acquire this deletion in their leukemic clone. The results indicate that ATM germ-line heterozygosity does not play a role in CLL but may influence disease progression through complete ATM loss and clonal expansion. The analysis of the clinical outcome among CLL patients from phase III LRF UK CLL4 trial identified a distinctive subgroup with a particularly poor prognosis. Those patients had bi-allelic inactivation of ATM gene and showed significantly reduced progression-free survival (PFS) compared to those with ATM wild-type or mono-allelic ATM defects. Furthermore, they had equally poor PFS as those with mono- and bi-allelic TP53 abnormalities. The clinical implication of this finding might include re-consideration of the treatment strategies for this particular subgroup of patients. The improved understanding of the biological background of progressive and resistant CLL tumours, such as those with TP53 or ATM defects, results in a development of further targeted treatment strategies. The assessment of their efficacy and toxicity could be facilitated by CLL xenograft models. The optimization strategies overcoming the limitations of existing xenograft model were investigated during the course of this study. The results showed that partial depletion of patient CD3+, CD4+ or CD25+ cells prior to injection into NOG mice can prolong the engraftment of CLL cells within xenogenic microenvironment hence, providing expanded period of time for testing new therapeutic agents.
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Bukowski-Wills, Jimi-Carlo. "Molecular links between genotype and phenotype in the albino-Swiss PKC-gamma mutant (AS/AGU) rat." Thesis, University of Glasgow, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.443440.

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Plong, Alexander. "Developmental and leaf senescence phenotype analysis in Arabidopsis thaliana| The atx4 (AT4G27910) mutant displays delayed leaf senescence and the kdm5b_1 (AT5G46910) mutant has larger seeds." Thesis, California State University, Long Beach, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=1603973.

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Leaf senescence is the final stage of leaf development that results in the highly ordered degeneration of cellular organelles and reallocation of nutrients to younger developing tissue. These cellular changes are accompanied by global changes in gene expression. Epigenetic modifications, such as DNA methylation, changes in histone variants, and covalent modification of histones have been shown to influence the expression of genes. Previous ChIP-seq and RNA-seq analyses revealed a correlation between the trimethylation of histone H3 lysine 4 (H3K4me3), a mark associated with active transcription, and the expression of a subset of senescence associated genes (SAGs) during leaf senescence in Arabidopsis thaliana. In this study, T-DNA insertion mutants of five histone methyltransferases (HMTases or ATX/ATXR) and five histone demethylases (HDMases or KDM5b) were examined to determine whether the expression of targeted SAGs was affected. In addition, total chlorophyll and protein levels, as well as plant development were investigated to determine whether these mutants function in regulating plant development and catabolism during senescence. The results show that while the expression of target SAGs were not affected by the mutants, other processes were affected. atx4 was observed to have higher levels of chlorophyll and protein, which indicates ATX4 may function in positively regulating catabolism during leaf senescence. Additionally, kdm5b_1 was observed to have larger seeds, which indicates KDM5b_1 may function to restrict seed size in Arabidopsis.

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Li, Xiaona. "Mass spectrometry-based metabolomics study on KRAS-mutant colorectal cancer and rheumatoid arthritis." HKBU Institutional Repository, 2018. https://repository.hkbu.edu.hk/etd_oa/540.

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Ample studies have shown that perturbation of metabolic phenotype is correlated with gene mutation and pathogenesis of colorectal cancer (CRC) and rheumatoid arthritis (RA). Mass spectrometry (MS)-based metabolomics as a powerful and stable approach is widely applied to bridge the gap from genotype/metabolites to phenotype. In CRC suffers, KRAS mutation accounts for 35%-45%. In previous study, SLC25A22 that encodes the mitochondrial glutamate transporter was found to be overexpressed in CRC tumor and thus to be essential for the proliferation of CRC cells harboring KRAS mutations. However, the role of SLC25A22 on metabolic regulation in KRAS-mutant CRC cells has not been comprehensively characterized. We performed non-targeted metabolomics, targeted metabolomics and isotope kinetic analysis of KRAS-mutant DLD1 cells with or without SLC25A22 knockdown using ultra-high performance liquid chromatography (UHPLC) coupled to Orbitrap MS and tandem MS (MS/MS). In global metabolomics analysis, 35 differentially regulated metabolites were identified, which were primarily involved in alanine, aspartate and glutamate metabolism, urea cycle and polyamine metabolism. Then targeted metabolomics analysis on intracellular metabolites, including tricarboxylic acid (TCA) cycle intermediates, amino acids and polyamines, was established by using LC-MS/MS coupled with an Amide BEH column. Targeted metabolomics analysis revealed that most TCA cycle intermediates, aspartate (Asp)-derived asparagine, alanine and ornithine (Orn)-derived polyamines were strongly down-regulated in SLC25A22 knockdown cells. Moreover, the targeted kinetic isotope analysis using [U-13C5]-glutamine as isotope tracer showed that most of the 13C-labeled TCA cycle intermediates were down-regulated in SLC25A22-silencing cells. Orn-derived polyamines were significantly decreased in SLC25A22 knockdown cells and culture medium. Meanwhile, accumulation of Asp in knockdown of GOT1 cells indicated that oxaloacetate (OAA) was majorly converted from Asp through GOT1. Exogenous addition of polyamines could significantly promote cell proliferation in DLD1 cells, highlighting their potential role as oncogenic metabolites that function downstream of SLC25A22-mediated glutamine metabolism. SLC25A22 acts as an essential metabolic regulator during CRC progression as promotes the synthesis of TCA cycle intermediates, Asp-derived amino acids and polyamines in KRAS-mutant CRC cells. Moreover, OAA and polyamine could promote KRAS-mutant CRC cell growth and survival. Rheumatoid arthritis (RA) is a chronic, inflammatory and symmetric autoimmune disease and a major cause of disability. However, there is insufficient pathological evidence in term of metabolic signatures of rheumatoid arthritis, especially the metabolic perturbation associated with gut microbiota (GM). Based on consistent criteria without special diet and therapeutic intervention to GM, we enrolled 50 RA patients and 50 healthy controls. On basis of the platform of UHPLC-MS and GC-MS, were performed for the non-targeted metabolomics to investigate alterations of endogenous metabolites in response to RA inflammation and interaction with GM. 32 and 34 significantly changed metabolites were identified in urine and serum of patients with RA, respectively. The altered metabolites were identified by HMDB, METLIN database or authentic standards, and mostly metabolites were attributed into tryptophan and phenylalanine metabolism, valine, leucine and isoleucine biosynthesis, aminoacyl-tRNA biosynthesis and citrate cycle. To obtain alterations of more components in tryptophan and phenylalanine metabolism, we developed and validated a targeted metabolomics method of 19 metabolites by using LC-QqQ MS. Combining the results of targeted metabolomics with global metabolomics, significantly up-regulated kynurenine (KYN), anthranilic acid (AA) and 5-hydroxylindoleacetic acid (HIAA) simultaneously in urine and serum was found to implicate the activation of tryptophan metabolism under the condition of RA, which acted pro-inflammatory roles in inflammation and was closely correlated with GM. IDO/TDO functioned as a pro-inflammation mediator was overexpressed in RA patients. Urinary kynurenic acid and serum serotonin that have impacts on anti-inflammation in immune system were down-regulated in RA patients. The levels of phenylacetic acid and phenyllactic acid serving as a pro-inflammatory and an anti-inflammatory agent, respectively, increased in serum of patients with RA. Moreover, certain essential amino acids (EAAs), and mostly conditional EAAs were decreased in RA patients, which have been reported to inhibit cell proliferation of immune cells. In particular, deficiency of branched chain amino acids (BCAAs, valine and isoleucine) was observed in serum of patients with RA, which may lead to muscle loss and cartilage damage. The specificity of all altered metabolites resulted from RA was considerably contributed through the GM-derived metabolites. The findings revealed that GM-modulated RA inflammation was mainly resulted from tryptophan and phenylalanine metabolism, and amino acid biosynthesis, which may provide more information for better understanding the RA mechanism.
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Books on the topic "Mutant Phenotype"

1

Colantonio, Concettina M. G proteins may be involved in the desensitization resistant phenotype of mutant Y1 adrenocortical tumor cells. Ottawa: National Library of Canada, 1996.

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Dean, Deyrick Osmond. Isolation and phenotypic characterisation of delation mutants of dnaK. Norwich: University of EastAnglia, 1991.

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NATO Advanced Research Workshop on Human Apolipoprotein Mutants: from Gene Structure to Phenotypic Expression (1988 Limone sul Garda, Italy). Human apolipoprotein mutants 2: From gene structure to phenotypic expression. New York: Plenum Press, 1989.

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Forgione, Nicole. Characterization of the PP1cgamma mutant phenotype using light and electron microscopy. 2006.

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Forgione, Nicole. Characterization of the PP1cy mutant phenotype using light and electron microscopy. 2006, 2006.

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Stujenske, Joseph Matthew. The bug eye mutant zebrafish exhibits glaucomatous visual deficits that arise with the onset of an enlarged eye phenotype. 2010.

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Adachi, Megumi, and Lisa M. Monteggia. Mecp2 Knockout in Mouse Models of Rett Syndrome. Oxford University Press, 2013. http://dx.doi.org/10.1093/med/9780199744312.003.0006.

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Chapter 6 reviews the phenotypes of the constitutive Mecp2 KO mutant mice, those generated by expressing RTT -causing mutations, and conditional Mecp2 KO mice in comparison to clinical phenotypes presented in patients with RTT. It also covers therapeutic approaches currently reported using these RTT -model mice.
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Sirtori, Cesare. Human Apolipoprotein Mutants 2: From Gene Structure to Phenotypic Expression. Springer, 2013.

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Sirtori, Cesare. Human Apolipoprotein Mutants 2: From Gene Structure to Phenotypic Expression. Springer, 2013.

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Sirtori, Cesare. Human Apolipoprotein Mutants 2: From Gene Structure to Phenotypic Expression. Springer London, Limited, 2013.

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Book chapters on the topic "Mutant Phenotype"

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Zhou, Chen-guang, Yuan-yuan Tan, Sophia Gossner, You-fa Li, Qing-yao Shu, and Karl-Heinz Engel. "Impact of cross-breeding on the metabolites of the low phytic acid rice mutant Os-lpa-MH86-1." In Mutation breeding, genetic diversity and crop adaptation to climate change, 433–43. Wallingford: CABI, 2021. http://dx.doi.org/10.1079/9781789249095.0044.

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Abstract Phytic acid (myo-inositol-1,2,3,4,5,6-hexakisphosphate), the major storage form of phosphorus in cereals, is considered as an antinutrient in food and feed. During the past few years, various cereals have been subjected to mutation breeding for generating low phytic acid (lpa) crops. Recently, it was demonstrated that reduction of phytic acid in the rice mutant Os-lpa-MH86-1 obtained by gamma irradiation was due to a disruption of OsSULTR3;3, an orthologue of the sulfate transporter family group 3 genes. The application of a GC/MS-based metabolite profiling approach revealed that the reduction of phytic acid was accompanied by changes in concentrations of metabolites from different classes in the Os-lpa-MH86-1 mutant.Lpa mutant lines often exhibit lower grain yield and seed viability compared with their wild-type parents. To improve the agronomic performance of the Os-lpa-MH86-1 mutant, cross-breeding with a commercial cultivar was performed. The resulting progenies were genotyped using molecular markers to identify homozygous wildtype and lpa mutants from generations F4 to F7. The objectives of this study were: (i) to observe the consistent metabolic changes in Os-lpa-MH86-1 lpa mutants by following their composition over several independent field trials; (ii) to investigate the impact of cross-breeding on the phytic acid content and the metabolic phenotype of the homozygous lpa mutant; and (iii) to assess the stability of the mutation-specific metabolite signature in the lpa progenies over several generations. Statistical assessment of the data via multivariate and univariate approaches demonstrated that the lpa trait and the mutation-induced metabolite signature in the lpa progenies were comparable to the progenitor Os-lpa-MH86-1 mutant and consistently expressed over generations. These findings extend the basis for implementing mutation breeding in the generation of lpa rice cultivars.
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Ramig, R. F. "Suppression and Reversion of Mutant Phenotype in Reovirus." In Current Topics in Microbiology and Immunology, 109–35. Berlin, Heidelberg: Springer Berlin Heidelberg, 1998. http://dx.doi.org/10.1007/978-3-642-72092-5_5.

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Roy, Sharmili, Xi Liang, Asanobu Kitamoto, Masaru Tamura, Toshihiko Shiroishi, and Michael S. Brown. "Phenotype Detection in Morphological Mutant Mice Using Deformation Features." In Advanced Information Systems Engineering, 437–44. Berlin, Heidelberg: Springer Berlin Heidelberg, 2013. http://dx.doi.org/10.1007/978-3-642-40760-4_55.

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Maliszewski, Katherine L. "Batch Transduction of Transposon Mutant Libraries for Rapid Phenotype Screening in Staphylococcus." In Methods in Molecular Biology, 75–81. New York, NY: Springer New York, 2015. http://dx.doi.org/10.1007/7651_2015_281.

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Abe, Tomoko, Hiroyuki Ichida, Yoriko Hayashi, Ryouhei Morita, Yuki Shirakawa, Kotaro Ishii, Tadashi Sato, Hiroki Saito, and Yutaka Okumoto. "Ion beam mutagenesis - an innovative and effective method for plant breeding and gene discovery." In Mutation breeding, genetic diversity and crop adaptation to climate change, 411–23. Wallingford: CABI, 2021. http://dx.doi.org/10.1079/9781789249095.0042.

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Abstract We have developed a unique technology for mutation induction of plants using energetic ion beams at the RI Beam Factory (RIBF) of Rikagaku Kenkyūjo (RIKEN) (Institute of Physical and Chemical Research). Ion beams effectively induce mutations at relatively low doses without severely inhibiting growth. The irradiation treatment can be given to various plant materials and mutation can be induced in a short time, between seconds and a few minutes. The linear energy transfer (LET) of ions depends on the nuclide and velocity. Since LET value affects the mutation frequency, it is an important parameter to determine the most effective irradiation condition in mutagenesis. We determined the most effective dose in each LET for mutation induction in imbibed rice seeds. Subsequently, we analysed the mutated DNA responsible for the phenotype in morphological mutants. Most of the mutations were small deletions of less than 100 bp. Irradiations of C-ions and Ne-ions are effective for plant breeding because of the very high mutation rate and sufficient energy to disrupt a single gene. On the other hand, all mutations induced by Ar-ion (290 keV/μm) irradiation were large deletions ranging from 176 bp to approximately 620 kb. The average number of mutations in the target exon regions was 7.3, 8.5 and 4.3 per M3 mutant plant in C-ions, Ne-ions and Ar-ions, respectively. The number of mutations induced by heavy-ion irradiation was relatively small. We could identify six responsible genes for eight mutants induced by C-ion and Ne-ion irradiations and two responsible genes for four mutants induced by Ar-ion irradiation. Three of these were genes not previously described.
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Bartoszewski, G., O. Fedorowicz, S. Malepszy, A. Smigocki, and K. Niemirowicz-Szczytt. "Unpredictable Phenotype Change Connected with Agrobacterium Tumefaciens Mediated Transformation of Non-Ripening Tomato Mutant." In Biology and Biotechnology of the Plant Hormone Ethylene II, 399–400. Dordrecht: Springer Netherlands, 1999. http://dx.doi.org/10.1007/978-94-011-4453-7_73.

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Brockman, J. A., and D. F. Hildebrand. "Temperature and Light Effects on the Expression of the Arabidopsis Linolenate Mutant Phenotype in Callus Cultures." In Biological Role of Plant Lipids, 583–84. Boston, MA: Springer US, 1989. http://dx.doi.org/10.1007/978-1-4684-1303-8_131.

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Friedman, T. B., J. T. Hinnant, M. Ghosh, E. T. Boger, S. Riazuddin, J. R. Lupski, L. Potocki, and E. R. Wilcox. "DFNB3, Spectrum of MYO15A Recessive Mutant Alleles and an Emerging Genotype-Phenotype Correlation." In Advances in Oto-Rhino-Laryngology, 124–30. Basel: KARGER, 2002. http://dx.doi.org/10.1159/000066824.

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Lundqvist, Udda. "Scandinavian mutation research during the past 90 years - a historical review." In Mutation breeding, genetic diversity and crop adaptation to climate change, 10–23. Wallingford: CABI, 2021. http://dx.doi.org/10.1079/9781789249095.0002.

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Abstract In 1928, the Swedish geneticists Herman Nilsson-Ehle and Åke Gustafsson started to act on their own ideas with the first experiments with induced mutations using diploid barley. They started with X-rays and UV irradiation. Very soon the first chlorophyll mutations were obtained and followed by the first 'vital' mutations Erectoides (ert) (Franckowiak and Lundqvist, 2001). Several other valuable mutations were identified as early maturity, high yielding, lodging resistant and characters with altered plant architecture. The experiments expanded to include other different types of irradiation, followed by chemical mutagenesis starting with mustard gas and concluding with sodium azide. The research brought a wealth of observations of general biological importance, such as the physiological effects of radiation as well as the difference in the mutation spectrum with respect to mutagens. This research was non-commercial, even if some mutants have become of important agronomic value. It peaked in activity during the 1950s to 1980s and, throughout, barley was the main experimental crop. About 12,000 different morphological and physiological mutants with a very broad phenotypic diversity were brought together and are incorporated in the Nordic Genetic Resource Centre (NordGen), Sweden. Several important mutant groups have been analysed in more detail genetically, with regard to mutagen specificity and gene cloning. These are: (i) early maturity mutants (Praematurum); (ii) six-rowed and intermedium-spike mutants; (iii) mutants affecting surface wax coating (Eceriferum); and (iv) mutants affecting rachis spike density (Erectoides). Some of these groups are presented in more detail in this review. Once work with induction of mutations began, it was evident that mutations should regularly be included in breeding programmes of crop plants. In Sweden, direct X-ray induced macro-mutants have been successfully released as cultivars, some of them having been used in combination breeding. Their importance for breeding is discussed in more detail.
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Das, Priyanka, Rajeev N. Bahuguna, Rohit Joshi, Sneh Lata Singla-Pareek, and Ashwani Pareek. "In search of mutants for gene discovery and functional genomics for multiple stress tolerance in rice." In Mutation breeding, genetic diversity and crop adaptation to climate change, 444–50. Wallingford: CABI, 2021. http://dx.doi.org/10.1079/9781789249095.0045.

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Abstract Mutation breeding is a commanding tool, which has been adapted to generate altered genetic material to study functional genomics, including understanding the molecular basis of stress tolerance. Hitherto, several rice lines have been generated through mutagenesis and the mutated genes responsible for the 'gain of function' in terms of plant architecture, stress tolerance, disease resistance and grain quality have been characterized. Oryza sativa L. cv. IR64 is a high-yielding rice cultivar but sensitive to abiotic stresses such as acute temperatures, salinity and drought. In this study, a population of rice IR64 mutants was generated using gamma irradiation. The population was then subjected to a preliminary phenotypic screening under abiotic stresses such as heat and salinity at the seedling stage. On the basis of root length, shoot length, fresh weight, dry weight and chlorophyll measurements, we identified eight 'gain-of-function' mutant lines and used them for further biochemical and molecular characterization. Phenotyping results demonstrated that the identified mutant plants have gained the potential to thrive under heat and salinity conditions. This information would be of wide scientific interest and helpful for developing novel cultivars able to maintain yield in saline, hot and dry areas.
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Conference papers on the topic "Mutant Phenotype"

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Garnik, E. Yu, D. V. Vilyanen, A. A. Vlasova, V. I. Belkov, V. I. Tarasenko, and Yu M. Konstantinov. "STAY-GREEN PHENOTYPE IN THE ARABIDOPSIS THALIANA GLUTAMATE DEHYDROGENASE MUTANT GDH1GDH2." In The All-Russian Scientific Conference with International Participation and Schools of Young Scientists "Mechanisms of resistance of plants and microorganisms to unfavorable environmental". SIPPB SB RAS, 2018. http://dx.doi.org/10.31255/978-5-94797-319-8-903-907.

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Chen, Chia-Yuan, Michael J. Patrick, Paola Corti, David Frakes, Beth L. Roman, and Kerem Pekkan. "In Vivo Hemodynamic Performance of Wild-Type vs. Mutant Zebrafish Embryos Using High-Speed Confocal Micro-PIV." In ASME 2010 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2010. http://dx.doi.org/10.1115/sbc2010-19317.

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In developing cardiovascular systems, definite performance comparison between disease and healthy hemodynamics requires quantitative tools to support advanced microscopy. Mutations in the activin receptor-like kinase 1 (ALK1) gene are responsible for the autosomal dominant vascular disease, hereditary hemorrhagic telangiectasia type 2 (HHT2), characterized by high flow arteriovenous malformations (AVMs) [1]. Recent studies show that the zebrafish mutant violet beauregrade (vbg), which harbors a mutation in alk1, develops an abnormal circulation with dilated cranial vessels and AVMs [2]. Quantitative understanding of mechanical influences on the alk1 mutant phenotype will aid treatment of HHT2 patients. Inspired by earlier studies that demonstrate the capability of using confocal micro-PIV technique to quantify biofluid dynamics in vivo [3], primarily in major vessels (dorsal aorta, vitelline veins), the present study focused on secondary branching great vessels of zebrafish embryos where microcirculation flow regimes are different. Furthermore, confocal microscopy, essentially being an imaging modality, requires rigorous validation efforts with respect to the gold standard measurement protocols (such as PIV) and synthetic scan data. Another objective of this work was to document the intra-species differences of wall shear stress (WSS) and flow physics during embryonic development in aortic arch systems of zebrafish [4].
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Berezovsky, Artem D., Andrea D. Transou, Susan M. Irtenkauf, Laura A. Hasselbach, Julie Koeman, Hoon Kim, Roel G. Verhaak, Tom Mikkelsen, Laila M. Poisson, and Ana C. deCarvalho. "Abstract 3491: Heterogeneous extrachromosomal amplification of mutant PDGFRA is associated with an aggressive phenotype in glioblastoma." In Proceedings: AACR Annual Meeting 2018; April 14-18, 2018; Chicago, IL. American Association for Cancer Research, 2018. http://dx.doi.org/10.1158/1538-7445.am2018-3491.

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Snodgrass, Ryan, Tim Chico, and Helen Arthur. "BS11 Inhibition of VEGF signalling mitigates the hereditary haemorrhagic telangiectasia-like phenotype in endoglin mutant zebrafish." In British Cardiovascular Society Virtual Annual Conference, ‘Cardiology and the Environment’, 7–10 June 2021. BMJ Publishing Group Ltd and British Cardiovascular Society, 2021. http://dx.doi.org/10.1136/heartjnl-2021-bcs.209.

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Joiner, Danese M., Bryan T. MacDonald, Xi He, Peter V. Hauschka, and Steven A. Goldstein. "Reduction of the Wnt Inhibitor Dkk1 Correlates With Improved Bone Mechanical and Morphological Properties in Mice." In ASME 2007 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2007. http://dx.doi.org/10.1115/sbc2007-175478.

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The Wnt/β-Catenin signaling pathway is a key regulator in bone development and bone homeostasis. Inactivating mutations in the Wnt co-receptor Low density lipoprotein Receptor related Protein 5 (LRP5) results in osteoporosis while “activating” mutations in LRP5 results in high bone mass. Dickkopf-1 (Dkk1) is a secreted Wnt inhibitor that binds to LRP5 and LRP6 reducing their availability to form a complex with Wnt and Frizzled and resulting in unrestrained Wnt signaling. It is expected that a decrease in Dkk1 will result in an increase in Wnt activity and ultimately a high bone mass phenotype. An allelic series of Dkk1 mutant mice were generated to examine the affects of reduced Dkk1 levels on bone density, morphology, and mechanical properties.
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Lim, Sun Min, Hyun Jung Kim, Young Ho Ban, Sang Jun Ha, and Byoung Chul Cho. "Abstract 4663: Acquired resistance to gefitinib is associated with cancer stem-like phenotype and EMT in EGFR mutant lung adenocarcinoma." In Proceedings: AACR 104th Annual Meeting 2013; Apr 6-10, 2013; Washington, DC. American Association for Cancer Research, 2013. http://dx.doi.org/10.1158/1538-7445.am2013-4663.

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Jones, Laundette P., Destiney Buelto, Elaine Tago, and Kwadwo Owusu-Boaitey. "Abstract 3278: Sustained multilocular adipose tissue phenotype in adult Brca1 mutant mouse mammary gland is correlated with an increase in BMP7." In Proceedings: AACR 103rd Annual Meeting 2012‐‐ Mar 31‐Apr 4, 2012; Chicago, IL. American Association for Cancer Research, 2012. http://dx.doi.org/10.1158/1538-7445.am2012-3278.

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Le, Xiuning, Marcelo V. Negrao, Alexandre Reuben, Won-Chul Lee, Edwin Parra, Jun Li, Tatiana Karpinets, et al. "Abstract 5028: Characterization of the tumor immune microenvironment in treatment-naïve EGFR-mutant NSCLC uncovers a low IFN-gamma suppressive immune phenotype." In Proceedings: AACR Annual Meeting 2019; March 29-April 3, 2019; Atlanta, GA. American Association for Cancer Research, 2019. http://dx.doi.org/10.1158/1538-7445.sabcs18-5028.

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Le, Xiuning, Marcelo V. Negrao, Alexandre Reuben, Won-Chul Lee, Edwin Parra, Jun Li, Tatiana Karpinets, et al. "Abstract 5028: Characterization of the tumor immune microenvironment in treatment-naïve EGFR-mutant NSCLC uncovers a low IFN-gamma suppressive immune phenotype." In Proceedings: AACR Annual Meeting 2019; March 29-April 3, 2019; Atlanta, GA. American Association for Cancer Research, 2019. http://dx.doi.org/10.1158/1538-7445.am2019-5028.

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TRUKHACHEV, Vladimir, Sergey OLEYNIK, Nikolay ZLYDNEV, and Vitaliy MOROZOV. "SCREENING OF COMPLEX VERTEBRAL MALFORMATION (CVM) AND BOVINE LEUKOCYTE ADHESION DEFICIENCY (BLAD) IN THE AYRSHIRE CATTLE BREED IN THE NORTH CAUCASUS." In RURAL DEVELOPMENT. Aleksandras Stulginskis University, 2018. http://dx.doi.org/10.15544/rd.2017.142.

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The Ayrshire dairy breed is renowned for producing large quantities of high quality milk and, therefore, is frequently used for crossbreeding. However, various hereditary anomalies caused by gene mutations have been recently recorded in calves produced by some Ayrshire sires. Most of these anomalies were shown to have a recessive inheritance pattern, thus imposing a threat of unpredictable dramatic changes in cattle genotypes under such factors as genetic drift, selection and inbreeding. The purpose of this study was to examine the susceptibility of the Ayrshire cattle bred in the North Caucasus to such hereditary abnormalities as complex vertebral malformation (CVM) and bovine leukocyte adhesion deficiency (BLAD). The investigation was carried out on 16 cows with various phenotype and reproduction disorders that were selected based on a three-year veterinary observation of 440 livestock animals. The target group cows were generally the descendants of Hannulan Yaskiyri, Riihiviidan Urho Errant and O.R. Lihting. The results demonstrated that no animals under study were the carriers of these genetic disorders, which proved the mutant alleles of BLAD and CVM to be absent from the Ayrshire cattle livestock bred in the North Caucasus. Therefore, the sires of these cattle can be successfully used for breeding.
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Reports on the topic "Mutant Phenotype"

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Freeman, Stanley, and Russell J. Rodriguez. The Interaction Between Nonpathogenic Mutants of Colletotrichum and Fusarium, and the Plant Host Defense System. United States Department of Agriculture, September 2000. http://dx.doi.org/10.32747/2000.7573069.bard.

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The intent of this proposal was to study the interaction between nonpathogenic mutants of Colletotrichum magna and Fusarium oxysporum, and the cucurbit host defense system. We had shown previously that a nonpathogenic endophytic mutant path- 1 of C. magna, caused no visible disease symptoms but protected watermelon seedlings from disease caused by the wildtype isolate and F. o. niveum. Objectives were: 1) Determine the microscopic, biochemical and molecular genetic interaction between "protected" (path- 1 colonized) cucurbit hosts and wildtype isolates of C. magna; 2) Isolate non-pathogenic mutants of F.o. melonis and test feasibility for protecting plants against fungal diseases. We found that path-1 caused no visible disease symptoms in cucurbit seedlings but conferred disease resistance against pathogenic isolates of C. magna, C. orbiculare, and F. oxysporum. Disease resistance conferred by path-1 correlated to a decrease in the time of activation of host defense systems after exposure of path-1 colonized plants to virulent pathogens. This was determined by monitoring the biochemical activity of PAL and peroxidase, and the deposition of lignin. It appears that path-1-conferred disease resistance is a multigenic phenomenon which should be more difficult for pathogen to overcome than single gene conferred resistance. Based on the benefits conferred by path-1, we have defined this mutant as expressing a mutualistic lifestyle. REMI (restriction enzyme-mediated integration) nonpathogenic mutants were also isolated using pHA1.3 plasmid linearized with Hind III and transformed into wildtype C. magna. The integrated vector and flanking genomic DNA sequences in REMI mutant R1 was re-isolated and cloned resulting in a product of approximately 11 kb designated pGMR1. Transformations of wildtype C. magna with pGMR1 resulted in the same non-pathogenic phenotype. A nonpathogenic mutant of F.o. melonis (pathogenic to melon) was isolated that colonized melon plants but elicited no disease symptoms in seedlings and conferred 25 - 50% disease protection against the virulent wildtype isolate. Subsequently, nonpathogenic mutant isolates of F.o. niveum (pathogenic to watermelon) were also isolated. Their protection capacity against the respective wildtype parent is currently under investigation. This research has provided information toward a better understanding of host-parasite interactions; specifically, endophytes, pathogens and their hosts. It will also allow us to assess the potential for utilizing nonpathogenic mutants as biological control agents against fungal pathogens and isolating molecular genetic factors of pathogenicity in Fusarium.
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Ori, Naomi, and Mark Estelle. Specific mediators of auxin activity during tomato leaf and fruit development. United States Department of Agriculture, January 2012. http://dx.doi.org/10.32747/2012.7597921.bard.

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The plant hormone auxin is involved in numerous developmental processes, including leaf and fruit development. The tomato (Solanumlycopersicum) gene ENTIRE (E) encodes an auxin-response inhibitor from the Aux/IAA family. While most loss-offunction mutations in Aux/IAA genes are similar to the wild type due to genetic redundancy, entire (e) mutants show specific effects on leaf and fruit development. e mutants have simple leaves, in contrast to the compound leaves of wild type tomatoes. In addition, e plants produce parthenocarpic fruits, in which fruit set occurs independently of fertilization. The aim of this research program was to utilize the e mutation to identify and characterize genes that mediate the specific effect of auxin in leaf and fruit development. The specific objectives of the project were to: 1. Characterize and map modifiers of the e leaf phenotype. 2. Characterize and map suppressors of the e fruit phenotype. 3. Dissect the developmental specificity of the E gene. 4. Examine the effect of fruit-overexpression of identified genes on fruit set and seed production. To identify mediators of auxin in leaf development, we mainly focused on one mutant, crawling elephant (crel, previously called t282), which showed substantial suppression of the e phenotype and other auxin-relatedphenotypes. We have identified the CREL gene as a homolog of the Arabidopsis VRN5 gene, involved in recruiting polycomb silencing complexes to specific targets. We showed that CREL affects auxin sensitivity in tomato. Suppressors of the e fruit phenotype have been further characterized and selected for more profound effects. Expression profiling by RNAseq was used to analyze the effect of e as well as crel on gene expression in leaves and fruits. This analysis has identified putative E and CREL targets. We have initiated studies to assess the role of some of these targets in flower and fruit development. The research has identified potential mediators of auxin response in leaf, flower and fruit development.
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Splitter, Gary A., Menachem Banai, and Jerome S. Harms. Brucella second messenger coordinates stages of infection. United States Department of Agriculture, January 2011. http://dx.doi.org/10.32747/2011.7699864.bard.

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Aim 1: To determine levels of this second messenger in: a) B. melitensiscyclic-dimericguanosinemonophosphate-regulating mutants (BMEI1448, BMEI1453, and BMEI1520), and b) B. melitensis16M (wild type) and mutant infections of macrophages and immune competent mice. (US lab primary) Aim 2: To determine proteomic differences between Brucelladeletion mutants BMEI1453 (high cyclic-dimericguanosinemonophosphate, chronic persistent state) and BMEI1520 (low cyclicdimericguanosinemonophosphate, acute virulent state) compared to wild type B. melitensisto identify the role of this second messenger in establishing the two polar states of brucellosis. (US lab primary with synergistic assistance from the Israel lab Aim 3: Determine the level of Brucellacyclic-dimericguanosinemonophosphate and transcriptional expression from naturally infected placenta. (Israel lab primary with synergistic assistance from the US lab). B. Background Brucellaspecies are Gram-negative, facultative intracellular bacterial pathogens that cause brucellosis, the most prevalent zoonosis worldwide. Brucellosis is characterized by increased abortion, weak offspring, and decreased milk production in animals. Humans are infected with Brucellaby consuming contaminated milk products or via inhalation of aerosolized bacteria from occupational hazards. Chronic human infections can result in complications such as liver damage, orchitis, endocarditis, and arthritis. Brucellaspp. have the ability to infect both professional and non-professional phagocytes. Because of this, Brucellaencounter varied environments both throughout the body and within a cell and must adapt accordingly. To date, few virulence factors have been identified in B. melitensisand even less is known about how these virulence factors are regulated. Subsequently, little is known about how Brucellaadapt to its rapidly changing environments, and how it alternates between acute and chronic virulence. Our studies suggest that decreased concentrations of cyclic dimericguanosinemonophosphate (c-di-GMP) lead to an acute virulent state and increased concentrations of c-di-GMP lead to persistent, chronic state of B. melitensisin a mouse model of infection. We hypothesize that B. melitensisuses c-di-GMP to transition from the chronic state of an infected host to the acute, virulent stage of infection in the placenta where the bacteria prepare to infect a new host. Studies on environmental pathogens such as Vibrio choleraeand Pseudomonas aeruginosasupport a mechanism where changes in c-di-GMP levels cause the bacterium to alternate between virulent and chronic states. Little work exists on understanding the role of c-di-GMP in dangerous intracellular pathogens, like Brucellathat is a frequent pathogen in Israeli domestic animals and U.S. elk and bison. Brucellamust carefully regulate virulence factors during infection of a host to ensure proper expression at appropriate times in response to host cues. Recently, the novel secondary signaling molecule c-di-GMP has been identified as a major component of bacterial regulation and we have identified c-di-GMP as an important signaling factor in B. melitensishost adaptation. C. Major conclusions, solutions, achievements 1. The B. melitensis1453 deletion mutant has increased c-di-GMP, while the 1520 deletion mutant has decreased c-di-GMP. 2. Both mutants grow similarly in in vitro cultures; however, the 1453 mutant has a microcolony phenotype both in vitro and in vivo 3. The 1453 mutant has increased crystal violet staining suggesting biofilm formation. 4. Scanning electron microscopy revealed an abnormal coccus appearance with in increased cell area. 5. Proteomic analysis revealed the 1453 mutant possessed increased production of proteins involved in cell wall processes, cell division, and the Type IV secretion system, and a decrease in proteins involved in amino acid transport/metabolism, carbohydrate metabolism, fatty acid production, and iron acquisition suggesting less preparedness for intracellular survival. 6. RNAseq analysis of bone marrow derived macrophages infected with the mutants revealed the host immune response is greatly reduced with the 1453 mutant infection. These findings support that microlocalization of proteins involved in c-di-GMP homeostasis serve a second messenger to B. melitensisregulating functions of the bacteria during infection of the host.
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Horwitz, Benjamin A., and Barbara Gillian Turgeon. Fungal Iron Acquisition, Oxidative Stress and Virulence in the Cochliobolus-maize Interaction. United States Department of Agriculture, March 2012. http://dx.doi.org/10.32747/2012.7709885.bard.

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Our project focused on genes for high affinity iron acquisition in Cochliobolus heterostrophus, a necrotrophic pathogen of maize, and their intertwined relationship to oxidative stress status and virulence of the fungus on the host. An intriguing question was why mutants lacking the nonribosomal peptide synthetase (NRPS) gene (NPS6) responsible for synthesis of the extracellular siderophore, coprogen, are sensitive to oxidative stress. Our overall objective was to understand the mechanistic connection between iron stress and oxidative stress as related to virulence of a plant pathogen to its host. The first objective was to examine the interface where small molecule peptide and reactive oxygen species (ROS) mechanisms overlap. The second objective was to determine if the molecular explanation for common function is common signal transduction pathways. These pathways, built around sensor kinases, response regulators, and transcription factors may link sequestering of iron, production of antioxidants, resistance to oxidative stress, and virulence. We tested these hypotheses by genetic manipulation of the pathogen, virulence assays on the host plant, and by following the expression of key fungal genes. An addition to the original program, made in the first year, was to develop, for fungi, a genetically encoded indicator of redox state based on the commercially available Gfp-based probe pHyper, designed for animal cell biology. We implemented several tools including a genetically encoded indicator of redox state, a procedure to grow iron-depleted plants, and constructed a number of new mutants in regulatory genes. Lack of the major Fe acquisition pathways results in an almost completely avirulent phenotype, showing how critical Fe acquisition is for the pathogen to cause disease. Mutants in conserved signaling pathways have normal ability to regulate NPS6 in response to Fe levels, as do mutants in Lae1 and Vel1, two master regulators of gene expression. Vel1 mutants are sensitive to oxidative stress, and the reason may be underexpression of a catalase gene. In nps6 mutants, CAT3 is also underexpressed, perhaps explaining the sensitivity to oxidative stress. We constructed a deletion mutant for the Fe sensor-regulator SreA and found that it is required for down regulation of NPS6 under Fe-replete conditions. Lack of SreA, though, did not make the fungus over-sensitive to ROS, though the mutant had a slow growth rate. This suggests that overproduction of siderophore under Fe-replete conditions is not very damaging. On the other hand, increasing Fe levels protected nps6 mutants from inhibition by ROS, implying that Fe-catalyzed Fenton reactions are not the main factor in its sensitivity to ROS. We have made some progress in understanding why siderophore mutants are sensitive to oxidative stress, and in doing so, defined some novel regulatory relationships. Catalase genes, which are not directly related to siderophore biosynthesis, are underexpressed in nps6 mutants, suggesting that the siderophore product (with or without bound Fe) may act as a signal. Siderophores, therefore, could be a target for intervention in the field, either by supplying an incorrect signal or blocking a signal normally provided during infection. We already know that nps6 mutants cause smaller lesions and have difficulty establishing invasive growth in the host. Lae1 and Vel1 are the first factors shown to regulate both super virulence conferred by T-toxin, and basic pathogenicity, due to unknown factors. The mutants are also altered in oxidative stress responses, key to success in the infection court, asexual and sexual development, essential for fungal dissemination in the field, aerial hyphal growth, and pigment biosynthesis, essential for survival in the field. Mutants in genes encoding NADPH oxidase (Nox) are compromised in development and virulence. Indeed the triple mutant, which should lack all Nox activity, was nearly avirulent. Again, gene expression experiments provided us with initial evidence that superoxide produced by the fungus may be most important as a signal. Blocking oxidant production by the pathogen may be a way to protect the plant host, in interactions with necrotrophs such as C. heterostrophus which seem to thrive in an oxidant environment.
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5

Sharon, Amir, and Maor Bar-Peled. Identification of new glycan metabolic pathways in the fungal pathogen Botrytis cinerea and their role in fungus-plant interactions. United States Department of Agriculture, 2012. http://dx.doi.org/10.32747/2012.7597916.bard.

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The involvement of glycans in microbial adherence, recognition and signaling is often a critical determinant of pathogenesis. Although the major glycan components of fungal cell walls have been identified there is limited information available on its ‘minor sugar components’ and how these change during different stages of fungal development. Our aim was to define the role of Rhacontaining-glycans in the gray mold disease caused by the necrotrophic fungus B. cinerea. The research was built on the discovery of two genes, Bcdhand bcer, that are involved in formation of UDP-KDG and UDP-Rha, two UDP- sugars that may serve as donors for the synthesis of cell surface glycans. Objectives of the proposed research included: 1) To determine the function of B. cinereaBcDh and BcEr in glycan biosynthesis and in pathogenesis, 2) To determine the expression pattern of BcDH and BcERand cellular localization of their encoded proteins, 3) Characterize the structure and distribution of Rha- containing glycans, 4) Characterization of the UDP-sugar enzymes and potential of GTs involved in glycanrhamnosylation. To address these objectives we generated a series of B. cinereamutants with modifications in the bchdhand bcergenes and the phenotype and sugar metabolism in the resulting strains were characterized. Analysis of sugar metabolites showed that changes in the genes caused changes in primary and secondary sugars, including abolishment of rhamnose, however abolishment of rhamnose synthesis did not cause changes in the fungal phenotype. In contrast, we found that deletion of the second gene, bcer, leads to accumulation of the intermediate sugar – UDP- KDG, and that such mutants suffer from a range of defects including reduced virulence. Further analyses confirmed that UDP-KDG is toxic to the fungus. Studies on mode of action suggested that UDP-KDG might affect integrity of the fungal cell wall, possibly by inhibiting UDP-sugars metabolic enzymes. Our results confirm that bcdhand bcerrepresent a single pathway of rhamnose synthesis in B. cinerea, that rhamnose does not affect in vitro development or virulence of the fungus. We also concluded that UDP-KDG is toxic to B. cinereaand hence UDP-KDG or compounds that inhibit Er enzymes and lead to accumulation of UDP-KDG might have antifungal activity. This toxicity is likely the case with other fungi, this became apparent in a collaborative work with Prof. Bart Thomma of Wageningen University, NETHERLANDS . We have shown the deletion of ER mutant in Verticillium dahlia gave plants resistance to the fungal infection.
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Ohad, Nir, and Robert Fischer. Control of Fertilization-Independent Development by the FIE1 Gene. United States Department of Agriculture, August 2000. http://dx.doi.org/10.32747/2000.7575290.bard.

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A fundamental problem in biology is to understand how fertilization initiates reproductive development. During plant reproduction, one sperm cell fuses with the egg to form an embryo, whereas a second sperm cell fuses with the adjacent central cell nucleus to form the endosperm tissue that supports embryo and/or seedling development. To understand the mechanisms that initiate reproduction, we have isolated mutants of Arabidopsis that allow for replication of the central cell and subsequent endosperm development without fertilization. In this project we have cloned the MEA gene and showed that it encode a SET- domain polycomb protein. Such proteins are known to form chromatin-protein complexes that repress homeotic gene transcription and influence cell proliferation from Drosophylla to mammals. We propose a model whereby MEA and an additional polycomb protein we have cloned, FIE , function to suppress a critical aspect of early plant reproduction and endosperm development, until fertilization occurs. Using a molecular approach we were able to determine that FIE and MEA interact physically, suggesting that these proteins have been conserved also during the evolution of flowering plants. The analysis of MEA expression pattern revealed that it is an imprinted gene that displays parent-of- origin-dependent monoallelic expression specifically in the endosperm tissue. Silencing of the paternal MEA allele in the endosperm and the phenotype of mutant mea seeds support the parental conflict theory for the evolution of imprinting in plants and mammals. These results contribute new information on the initiation of endosperm development and provide a unique entry point to study asexual reproduction and apomixis which is expected to improve crop production.
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7

Obringer, John W. Bacteriophage T4D Gene 42 Mutants Exhibit a Defective Genetic Exclusion Phenotype. Fort Belvoir, VA: Defense Technical Information Center, February 1991. http://dx.doi.org/10.21236/ada235836.

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8

Chory, J., N. Aguilar, and C. A. Peto. The phenotype of Arabidopsis thaliana det1 mutants suggest a role for cytokinins in greening. Office of Scientific and Technical Information (OSTI), January 1990. http://dx.doi.org/10.2172/5603534.

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9

Dickman, Martin B., and Oded Yarden. Genetic and chemical intervention in ROS signaling pathways affecting development and pathogenicity of Sclerotinia sclerotiorum. United States Department of Agriculture, July 2015. http://dx.doi.org/10.32747/2015.7699866.bard.

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Abstract: The long-term goals of our research are to understand the regulation of sclerotial development and pathogenicity in S. sclerotior11111. The focus in this project was on the elucidation of the signaling events and environmental cues involved in the regulation of these processes, utilizing and continuously developing tools our research groups have established and/or adapted for analysis of S. sclerotiorum, Our stated objectives: To take advantage of the recent conceptual (ROS/PPs signaling) and technical (amenability of S. sclerotiorumto manipulations coupled with chemical genomics and next generation sequencing) developments to address and extend our fundamental and potentially applicable knowledge of the following questions concerning the involvement of REDOX signaling and protein dephosphorylation in the regulation of hyphal/sclerotial development and pathogenicity of S. sclerotiorum: (i) How do defects in genes involved in ROS signaling affect S. sclerotiorumdevelopment and pathogenicity? (ii) In what manner do phosphotyrosinephosphatases affect S. sclerotiorumdevelopment and pathogenicity and how are they linked with ROS and other signaling pathways? And (iii) What is the nature of activity of newly identified compounds that affect S. sclerotiori,111 growth? What are the fungal targets and do they interfere with ROS signaling? We have met a significant portion of the specific goals set in our research project. Much of our work has been published. Briefly. we can summarize that: (a) Silencing of SsNox1(NADPHoxidase) expression indicated a central role for this enzyme in both virulence and pathogenic development, while inactivation of the SsNox2 gene resulted in limited sclerotial development, but the organism remained fully pathogenic. (b) A catalase gene (Scatl), whose expression was highly induced during host infection is involved in hyphal growth, branching, sclerotia formation and infection. (c) Protein tyrosine phosphatase l (ptpl) is required for sclerotial development and is involved in fungal infection. (d) Deletion of a superoxidedismutase gene (Sssodl) significantly reduced in virulence on both tomato and tobacco plants yet pathogenicity was mostly restored following supplementation with oxalate. (e) We have participated in comparative genome sequence analysis of S. sclerotiorumand B. cinerea. (f) S. sclerotiorumexhibits a potential switch between biotrophic and necrotrophic lifestyles (g) During plant­ microbe interactions cell death can occur in both resistant and susceptible events. Non­ pathogenic fungal mutants S. sclerotior111n also cause a cell death but with opposing results. We investigated PCD in more detail and showed that, although PCD occurs in both circumstances they exhibit distinctly different features. The mutants trigger a restricted cell death phenotype in the host that unexpectedly exhibits markers associated with the plant hypersensitive (resistant) response. Using electron and fluorescence microscopy, chemical effectors and reverse genetics, we have established that this restricted cell death is autophagic. Inhibition of autophagy rescued the non-pathogenic mutant phenotype. These findings indicate that autophagy is a defense response in this interaction Thus the control of cell death, dictated by the plant (autophagy) סr the fungus (apoptosis), is decisive to the outcome of certain plant­ microbe interactions. In addition to the time and efforts invested towards reaching the specific goals mentioned, both Pls have initiated utilizing (as stated as an objective in our proposal) state of the art RNA-seq tools in order to harness this technology for the study of S. sclerotiorum. The Pls have met twice (in Israel and in the US), in order to discuss .נחd coordinate the research efforts. This included a working visit at the US Pls laboratory for performing RNA-seq experiments and data analysis as well as working on a joint publication (now published). The work we have performed expands our understanding of the fundamental biology (developmental and pathogenic) of S. sclerotioז111וז. Furthermore, based on our results we have now reached the conclusion that this fungus is not a bona fide necrotroph, but can also display a biotrophic lifestyle at the early phases of infection. The data obtained can eventually serve .נ basis of rational intervention with the disease cycle of this pathogen.
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Splitter, Gary, and Menachem Banai. Attenuated Brucella melitensis Rough Rev1 Vaccine. United States Department of Agriculture, January 2004. http://dx.doi.org/10.32747/2004.7585199.bard.

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The original objectives of the proposal were: 1. Compare mutants 444 and 710 to Rev1 (parent strain), and 16M (field strain) in murine and human macrophage lines for phenotypic differences. 2. Determine in vivo virulence and survival of the mutants 444 and 710 in guinea pigs and mice. 3. Determine humoral and cell-mediated immune responses induced by mutants 444 and 710 in guinea pigs and mice. 4. Determine in vivo protection of mice and guinea pigs provided by mutants 444 and 710 compared to Rev1. Background: While human and animal brucellosis are rare in the U.S., brucellosis caused by B. melitensis remains relatively constant in Israel. Despite a national campaign to control brucellosis in Israel, the misuse of Rev1 Elberg vaccine strain among pregnant animals has produced abortion storms raising concern of human infection due to vaccine excretion in the milk. Further, some commercial Rev1 vaccine lots can: a) produce persistent infection, b) infect humans, c) be horizontally transmitted, d) cause abortion, and e) induce a persistent anti-O-polysaccharide antibody response confounding the distinction between infected and vaccinated animals. In Israel, vaccination practices have not optimally protected the milk supply from Brucella and Rev 1 vaccine can exacerbate the problem. In addition, cattle vaccinated against B. abortus are not protected against B. melitensis supporting the need for an improved vaccine. A safe vaccine used in adult animals to produce herd resistance to infection and a vaccine that can be distinguished from virulent infection is needed. A rough Rev1 vaccine would be less virulent than the parental smooth strain and permit serologic distinction between vaccinated and infected animals. Advantages of the Rev1 vaccine foundation are: 1) Rev1 vaccination of sheep and goats against B. melintensisis approved; therefore, vaccines derived from the Rev1 foundation may be readily accepted by licensing agencies as well as commercial companies, and 2) considerable data exists on Rev1vaccination and Rev1 proteins. Therefore, a post-genomic vaccine against B. melitensis based on the Rev1 foundation would provide a great advantage. Major conclusions from our work are: 1) We have determined that mutant 710 is highly attenuated in macrophages compared to virulent field strain 16M and mutant 444. 2) We have confirmed that mutant 710 is highly attenuated in guinea pigs and mice. 3) We have determined immune responses induced by mutant 710 in animals. 4) We have determined in vivo protection of mice and guinea pigs provided by mutants 444 and 710 compared to Rev1, and importantly, mutant 710 provides a high level of protection against challenge with virulent B. melitensis 16M. Thus, our data support the goals of the grant and provide the foundation for a future vaccine useful against B. melitensis in Israel. Because of patent considerations, many of our findings with 444 and 710 have not yet been published. Scientific and Agricultural Implications: Our findings support the development of a vaccine against B. melitensis based on the mutant 710. Because strain 710 is a mutant of the Elberg Rev1 vaccine, commercialization is more likely than development of an entirely new, uncharacterized Brucella mutant or strain.
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