Literatura académica sobre el tema "PEX genes"
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Artículos de revistas sobre el tema "PEX genes"
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Subramani, Suresh. "PEX genes on the rise". Nature Genetics 15, n.º 4 (abril de 1997): 331–33. http://dx.doi.org/10.1038/ng0497-331.
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Baker, A., W. Charlton, B. Johnson, E. Lopez-Huertas, J. Oh, I. Sparkes y J. Thomas. "Biochemical and molecular approaches to understanding protein import into peroxisomes". Biochemical Society Transactions 28, n.º 4 (1 de agosto de 2000): 499–504. http://dx.doi.org/10.1042/bst0280499.
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Peroxisomes are eukaryotic organelles that perform diverse and variable functions. Although genetic studies in yeasts and mammals have identified approximately 20 genes (PEX genes) required for the biogenesis of this important organelle, biochemical studies of protein targeting and import have lagged behind and in many cases we have no idea of the function of the PEX gene products (peroxins). Using an import assay in vitro derived from sunflower cotyledon cells and recombinant proteins, we have obtained translocation intermediates on the peroxisome import pathway and are using cross-linking to identify interacting partners. We have also used antibodies raised against human PEX14 to inhibit the import of matrix proteins in this system. To obtain homologous antibodies for inhibition experiments, to immunoprecipitate cross-linked products and to enable us to study the import pathways of peroxins we have cloned and characterized plant orthologues of three PEX genes, PEX6, PEX10 and PEX14.
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Berner, Daniel, Ursula Hoja, Matthias Zenkel, James Julian Ross, Steffen Uebe, Daniela Paoli, Paolo Frezzotti et al. "The protective variant rs7173049 at LOXL1 locus impacts on retinoic acid signaling pathway in pseudoexfoliation syndrome". Human Molecular Genetics 28, n.º 15 (15 de abril de 2019): 2531–48. http://dx.doi.org/10.1093/hmg/ddz075.
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AbstractLOXL1 (lysyl oxidase-like 1) has been identified as the major effect locus in pseudoexfoliation (PEX) syndrome, a fibrotic disorder of the extracellular matrix and frequent cause of chronic open-angle glaucoma. However, all known PEX-associated common variants show allele effect reversal in populations of different ancestry, casting doubt on their biological significance. Based on extensive LOXL1 deep sequencing, we report here the identification of a common non-coding sequence variant, rs7173049A>G, located downstream of LOXL1, consistently associated with a decrease in PEX risk (odds ratio, OR = 0.63; P = 6.33 × 10−31) in nine different ethnic populations. We provide experimental evidence for a functional enhancer-like regulatory activity of the genomic region surrounding rs7173049 influencing expression levels of ISLR2 (immunoglobulin superfamily containing leucine-rich repeat protein 2) and STRA6 [stimulated by retinoic acid (RA) receptor 6], apparently mediated by allele-specific binding of the transcription factor thyroid hormone receptor beta. We further show that the protective rs7173049-G allele correlates with increased tissue expression levels of ISLR2 and STRA6 and that both genes are significantly downregulated in tissues of PEX patients together with other key components of the STRA6 receptor-driven RA signaling pathway. siRNA-mediated downregulation of RA signaling induces upregulation of LOXL1 and PEX-associated matrix genes in PEX-relevant cell types. These data indicate that dysregulation of STRA6 and impaired retinoid metabolism are involved in the pathophysiology of PEX syndrome and that the variant rs7173049-G, which represents the first common variant at the broad LOXL1 locus without allele effect reversal, mediates a protective effect through upregulation of STRA6 in ocular tissues.
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Johnson, Monique A., Hans R. Waterham, Galyna P. Ksheminska, Liubov R. Fayura, Joan Lin Cereghino, Oleh V. Stasyk, Marten Veenhuis, Aleksander R. Kulachkovsky, Andrei A. Sibirny y James M. Cregg. "Positive Selection of Novel Peroxisome Biogenesis-Defective Mutants of the Yeast Pichia pastoris". Genetics 151, n.º 4 (1 de abril de 1999): 1379–91. http://dx.doi.org/10.1093/genetics/151.4.1379.
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Abstract We have developed two novel schemes for the direct selection of peroxisome-biogenesis-defective (pex) mutants of the methylotrophic yeast Pichia pastoris. Both schemes take advantage of our observation that methanol-induced pex mutants contain little or no alcohol oxidase (AOX) activity. AOX is a peroxisomal matrix enzyme that catalyzes the first step in the methanol-utilization pathway. One scheme utilizes allyl alcohol, a compound that is not toxic to cells but is oxidized by AOX to acrolein, a compound that is toxic. Exposure of mutagenized populations of AOX-induced cells to allyl alcohol selectively kills AOX-containing cells. However, pex mutants without AOX are able to grow. The second scheme utilizes a P. pastoris strain that is defective in formaldehyde dehydrogenase (FLD), a methanol pathway enzyme required to metabolize formaldehyde, the product of AOX. AOX-induced cells of fld1 strains are sensitive to methanol because of the accumulation of formaldehyde. However, fld1 pex mutants, with little active AOX, do not efficiently oxidize methanol to formaldehyde and therefore are not sensitive to methanol. Using these selections, new pex mutant alleles in previously identified PEX genes have been isolated along with mutants in three previously unidentified PEX groups.
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Tomczyk-Socha, Martyna, Wojciech Tomczak y Anna Turno-Kręcicka. "The Importance of MicroRNA Expression in Pseudoexfoliation Syndrome". International Journal of Molecular Sciences 23, n.º 21 (31 de octubre de 2022): 13234. http://dx.doi.org/10.3390/ijms232113234.
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Pseudoexfoliation syndrome (PEX) is an important systemic disorder of the extracellular matrix, in which granular amyloid-like protein fibers accumulate in the anterior segment of the eyeball as well as in other organs. PEX is currently considered to be a multifactorial systemic disorder with genetic and environmental risk factors. The aim of this manuscript was to analyze miR expression in PEX. In recent years, an attempt has been made to investigate and describe the level of expression of selected miRs in PEX. Four polymorphisms of genes isolated from the blood that may be related to PEX were identified and miR-122-5p was found to be upregulated in patient blood. Furthermore, 18 miRs were identified with a statistically different expression in the aqueous humor. A significantly elevated expression of miR-125b was found in the anterior lens capsule, and four miRs were described, which may have a significant impact on the development of PEX. Regulatory miR molecules are gaining more and more importance in research aimed at identifying and isolating molecular markers related to the pathogenesis and prognosis of PEX, but further studies are needed.
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Kiel, Jan A. K. W., Marten Veenhuis y Ida J. van der Klei. "PEX Genes in Fungal Genomes: Common, Rare or Redundant". Traffic 7, n.º 10 (13 de septiembre de 2006): 1291–303. http://dx.doi.org/10.1111/j.1600-0854.2006.00479.x.
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Baes, Myriam y Paul P. Van Veldhoven. "Generalised and conditional inactivation of Pex genes in mice". Biochimica et Biophysica Acta (BBA) - Molecular Cell Research 1763, n.º 12 (diciembre de 2006): 1785–93. http://dx.doi.org/10.1016/j.bbamcr.2006.08.018.
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Tomczyk-Socha, Martyna, Julia Kręcicka, Marta Misiuk-Hojło y Anna Turno-Kręcicka. "MicroRNA Expression in Pseudoexfoliation Syndrome with the Use of Next-Generation Sequencing". Genes 13, n.º 4 (25 de marzo de 2022): 582. http://dx.doi.org/10.3390/genes13040582.
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Pseudoexfoliation syndrome (PEX) is a clinically important and biologically intriguing systemic disorder of the extracellular matrix. PEX etiopathogenesis was proved to be connected to multiple genes and other factors. However, the exact etiopathogenesis remains unknown. The aim of this study was to analyze miR expression in PEX using next-generation sequencing. An attempt was made to find the most commonly occurring miR in PEX, to evaluate miR that may have an essential role in the etiology of PEX syndrome. In addition, the correlation between the selected miRs’ expressions and age was investigated. Anterior lens capsules were obtained during cataract surgery. Next-generation sequencing was conducted on Illumina MiSeq. The average age was 68.2 years (with standard deviation +/− 6.92 years). Ten miRs with the highest level of expression represent approx. 95% of all readings. Four miRs with statistically significant differences in expression between groups have been distinguished: miR-671-3p, miR374a-5p, miR-1307-5p and miR-708-5p. The relationship between the most frequent miRs’ expressions and age has been evaluated and no correlation has been detected. In view of the above, it seems reasonable to examine the influence of miR on the biogenesis of PEX. Further studies on miR-671-3p, miR-374a-5p, miR-1307-5p and miR-708-5p expression in PEX are needed.
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Zhang, Hongji, Xiang Cheng, Meihong Deng, Allan Tsung y Hai Huang. "Preoperative exercise therapy attenuates liver metastases following surgical stress by inducing Kupffer cells-mediated anti-tumor immunity". Journal of Immunology 208, n.º 1_Supplement (1 de mayo de 2022): 118.09. http://dx.doi.org/10.4049/jimmunol.208.supp.118.09.
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Abstract Introduction Resection of colorectal cancer hepatic metastases improves overall disease-free survival. Unfortunately, not all patients have a successful surgical outcome. Pre-operative exercise therapy (PEx) have been demonstrated to be beneficial in the prevention of post-operative complications. We hypothesize that PEx initially reverts pro-tumorigenic inflammatory responses following surgical stress and maintains an anti-tumor immune microenvironment through modulating Kupffer cells (KCs) with anti-tumor immunity. Methods 8W C57BL/6 mice were randomly divided into PEx and sedentary (Sed) groups, mice with PEx run on a motorized treadmill at a speed of 12.5 m/min for 60 min/day, 5 days/W for 4 weeks. 105 MC38 cells were injected directly through portal vein and surgical stress was subjected to partial hepatic ischemia and reperfusion model. Both hepatic and tumor CD45+ cells from PEx or Sed mice 3 W after IR were submitted for single-cell RNA sequencing (scRNA-seq). Results 4 weeks of PEx significantly reduces metastasis in the liver along 3 weeks after IR, compared with Sed controls. For the scRNA-seq, 11 cell lineages were identified and annotated according to the transcriptomic profile of feature genes expression. Surprisingly, discontinued 4-week-PEx still led to a significant transcriptomic shift in the KCs. 3 clusters from the entire KCs population were unique in PEx mice. In contrast, 2 Clusters were derived from Sed mice. PEx-relevant KCs are enriched in gene expression related to the anti-tumor phenotype, whereas Sed-relevant KCs are enriched in gene expression related to pro-tumor or immunosuppressive phenotype, which suggests that PEx modulates transcriptomic changes in KCs towards an anti-tumor phenotype. Supported by National Institutes of Health R01-CA214865-01 and R01-GM95566-06 to AT, National Institutes of Health R01-AI152044 to MD, and National Institutes of Health R01-GM137203 and Joseph A. Patrick Research Fellowship in Transplantation to HH.
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Zhang, Hongji, Xiang Cheng, Chengli Shen, Meihong Deng, Allan Tsung y Hai Huang. "Abstract 2109: Preoperative exercise therapy attenuates the progression of liver metastases following surgical stress by inducing Kupffer cells-mediated anti-tumor trained immunity". Cancer Research 82, n.º 12_Supplement (15 de junio de 2022): 2109. http://dx.doi.org/10.1158/1538-7445.am2022-2109.
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Abstract Introduction: Colorectal cancer (CRC) is a devastating disease, causing mortality worldwide, with the majority of the patients dying from hepatic metastasis. Resection of hepatic metastases improves overall disease-free survival. Unfortunately, not all patients have a successful surgical outcome. Pre-operative exercise therapy (PEx) have been demonstrated to be beneficial in the prevention of post-operative complications. Trained immunity in myeloid cells leads to an aggravated long-term inflammatory phenotype upon a secondary stimulation, a process that results from orchestrated metabolic-epigenetic changes. We hypothesize that PEx initially reverts pro-tumorigenic inflammatory responses following surgical stress and maintains an anti-tumor immune microenvironment through modulating Kupffer cells (KCs) with anti-tumor immunity. Methods: 8-week C57BL/6 mice were randomly divided into PEx and sedentary (Sed) groups, mice with PEx run on a motorized treadmill at a speed of 12.5 m/min for 60 min/day, 5 days/week for 4 weeks. 105 MC38 cells were injected directly through portal vein and surgical stress was subjected to a model of partial hepatic ischemia and reperfusion. The tumor progression was determined by bioluminescent imaging weekly. Both hepatic and tumor CD45+ cells from PEx or Sed mice 3 weeks after IR were submitted for single-cell RNA sequencing (scRNA-seq). Results: 4 weeks of PEx significantly reduces metastasis in the liver along 3 weeks after IR, compared with Sed controls. For the scRNA-seq, 11 cell lineages (KCs, monocytes, neutrophils, DCs, TAMs, TANs, B cells, CD4+ T cells, CD8+ T cells, NK cells, and NKT cells) were identified and annotated according to the transcriptomic profile of feature genes expression. Surprisingly, discontinued 4-week-PEx still led to a significant transcriptomic shift in the KCs. 3 clusters from the entire KCs population were unique in PEx mice. In contrast, 2 Clusters were derived from Sed mice. PEx-relevant KCs are enriched in gene expression related to the anti-tumor phenotype, whereas Sed-relevant KCs are enriched in gene expression related to pro-tumor or immunosuppressive phenotype, which suggests that PEx modulates transcriptomic changes in KCs towards an anti-tumor phenotype. Furthermore, with our established ex vivo trained immunity assay, we observe a clear induction of trained immunity in PEx-KCs when co-cultured with MC38 tumor cells, with noticeably higher levels of anti-tumor cytokines interferon (IFN)-γ and TNF-α compared to Sed-KCs. Summary: Our study is one of the first to show that PEx alters the hepatic immune microenvironment by shifting KC to a tumoricidal phenotype. This work offers a rationale for PEx for cancer patients undergoing liver surgery thereby decreasing post-operative metastases and morbidity. Citation Format: Hongji Zhang, Xiang Cheng, Chengli Shen, Meihong Deng, Allan Tsung, Hai Huang. Preoperative exercise therapy attenuates the progression of liver metastases following surgical stress by inducing Kupffer cells-mediated anti-tumor trained immunity [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 2109.
Tesis sobre el tema "PEX genes"
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Nguyen, Tam Hong. "Pex13 Mutant Mice as Models for the Peroxisome Biogenesis Disorders". Thesis, Griffith University, 2008. http://hdl.handle.net/10072/366797.
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Zellweger syndrome (ZS) is the most severe form of a spectrum of disorders resulting from mutations in PEX genes, genes that encode proteins necessary for peroxisome biogenesis. Loss of functional peroxiosmes leads to disruption of multiple metabolic pathways involving the peroxisome, including very long chain fatty acid oxidation and plasmalogen and bile acid synthesis. ZS patients exhibit a range of clinical abnormalities, including facial dysmorphism, cataracts, hypotonia, seizures, psychomotor retardation, and hearing impairment. In terms of tissue pathology, there are also wide ranging effects, including neuronal migration defects, hepatomegaly, retinopathy, and renal cysts. Pex13 encodes a peroxisomal membrane protein that is essential for peroxisome biogenesis. Previous work in this laboratory resulted in the generation of a Pex13-null mouse model for the purpose of investigating the pathogenesis of Zellweger syndrome. The work in the first part of this thesis extends these studies and describes the generation and initial characterisation of tissue-specific Pex13 mouse models. These tissue-specific models are expected be useful tools for analysis of the impact of localised, brain- and liver-specific elimination of peroxisomes on the pathogenesis of ZS. In addition, in the second part of the thesis, a separate and novel hypothesis is addressed as an explanation for the molecular pathogenesis of ZS, through investigating the relationship between reduced peroxisome abundance and microtubule-mediated peroxisome trafficking.
Pex13 brain mutant mice were generated by mating the previously generated Pex13-floxed mice with mice expressing Cre recombinase under the control of the neuron-specific rat nestin promoter. Pex13 brain mutant mice displayed growth retardation beginning at day 5 postnatal, with gradual deterioration until death at approximately day 22 postnatal. Other clinical features included contracted postures, under-developed lower body mass, abnormal and unsteady gait, and abnormal motor coordination. In terms of brain metabolic function, these mice exhibited significant defects in plasmalogen synthesis, but, surprisingly, VLCFA levels were similar to those of littermate control mice. Significantly, peroxisome elimination in brain resulted in increased levels of plasmalogen levels in liver of Pex13 brain mutant mice. Consistent with the expected pathology resulting from deficiency of brain peroxisomes, brain mutants exhibited defective neuronal migration characterised by increased cellular density in the intermediate zone of the neocortex. Microarray analysis of total brain RNA from Pex13 brain mutants revealed several functionally-linked pathways associated with the differentially expressed genes, including cell-cell signalling, cell compromise/death, lipid metabolism, cell movement, and serotonin synthesis.Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Biomolecular and Physical Sciences
Science, Environment, Engineering and Technology
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Maxwell, Megan Amanda y n/a. "PEX1 Mutations in Australasian Patients with Disorders of Peroxisome Biogenesis". Griffith University. School of Biomolecular and Biomedical Science, 2004. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20040219.100649.
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The peroxisome is a subcellular organelle that carries out a diverse range of metabolic functions, including the b-oxidation of very long chain fatty acids, the breakdown of peroxide and the a-oxidation of fatty acids. Disruption of peroxisome metabolic functions leads to severe disease in humans. These diseases can be broadly grouped into two categories: those in which a single enzyme is defective, and those known as the peroxisome biogenesis disorders (PBDs), which result from a generalised failure to import peroxisomal matrix proteins (and consequently result in disruption of multiple metabolic pathways). The PBDs result from mutations in PEX genes, which encode protein products called peroxins, required for the normal biogenesis of the peroxisome. PEX1 encodes an AAA ATPase that is essential for peroxisome biogenesis, and mutations in PEX1 are the most common cause of PBDs worldwide. This study focused on the identification of mutations in PEX1 in an Australasian cohort of PBD patients, and the impact of these mutations on PEX1 function. As a result of the studies presented in this thesis, twelve mutations in PEX1 were identified in the Australasian cohort of patients. The identified mutations can be broadly grouped into three categories: missense mutations, mutations directly introducing a premature termination codon (PTC) and mutations that interrupt the reading frame of PEX1. The missense mutations that were identified were R798G, G843D, I989T and R998Q; all of these mutations affect amino acid residues located in the AAA domains of the PEX1 protein. Two mutations that directly introduce PTCs into the PEX1 transcript (R790X and R998X), and four frameshift mutations (A302fs, I370fs, I700fs and S797fs) were identified. There was also one mutation found in an intronic region (IVS22-19A>G) that is presumed to affect splicing of the PEX1 mRNA. Three of these mutations, G843D, I700fs and G973fs, were found at high frequency in this patient cohort. At the commencement of these studies, it was hypothesised that missense mutations would result in attenuation of PEX1 function, but mutations that introduced PTCs, either directly or indirectly, would have a deleterious effect on PEX1 function. Mutations introducing PTCs are thought to cause mRNA to be degraded by the nonsense-mediated decay of mRNA (NMD) pathway, and thus result in a decrease in PEX1 protein levels. The studies on the cellular impact of the identified PEX1 mutations were consistent with these hypotheses. Missense mutations were found to reduce peroxisomal protein import and PEX1 protein levels, but a residual level of function remained. PTC-generating mutations were found to have a major impact on PEX1 function, with PEX1 mRNA and protein levels being drastically reduced, and peroxisomal protein import capability abolished. Patients with two missense mutations showed the least impact on PEX1 function, patients with two PTC-generating mutations had a severe defect in PEX1 function, and patients carrying a combination of a missense mutation and a PTC-generating mutation showed levels of PEX1 function that were intermediate between these extremes. Thus, a correlation between PEX1 genotype and phenotype was defined for the Australasian cohort of patients investigated in these studies. For a number of patients, mutations in the coding sequence of one PEX1 allele could not be identified. Analysis of the 5' UTR of this gene was therefore pursued for potential novel mutations. The initial analyses demonstrated that the 5' end of PEX1 extended further than previously reported. Two co-segregating polymorphisms were also identified, termed 137 T>C and 53C>G. The -137T>C polymorphism resided in an upstream, in-frame ATG (termed ATG1), and the possibility that the additional sequence represented PEX1 coding sequence was examined. While both ATGs were found to be functional by virtue of in vitro and in vivo expression investigations, Western blot analysis of the PEX1 protein in patient and control cell extracts indicated that physiological translation of PEX1 was from the second ATG only. Using a luciferase reporter approach, the additional sequence was found to exhibit promoter activity. When examined alone the -137T>C polymorphism exerted a detrimental effect on PEX1 promoter activity, reducing activity to half that of wild-type levels, and the -53C>G polymorphism increased PEX1 promoter activity by 25%. When co-expressed (mimicking the physiological condition) these polymorphisms compensated for each other to bring PEX1 promoter activity to near wild-type levels. The PEX1 mutations identified in this study have been utilised by collaborators at the National Referral Laboratory for Lysosomal, Peroxisomal and Related Genetic Disorders (based at the Women's and Children's Hospital, Adelaide), in prenatal diagnosis of the PBDs. In addition, the identification of three common mutations in Australasian PBD patients has led to the implementation of screening for these mutations in newly referred patients, often enabling a precise diagnosis of a PBD to be made. Finally, the strong correlation between genotype and phenotype for the patient cohort investigated as part of these studies has generated a basis for the assessment of newly identified mutations in PEX1.
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Maxwell, Megan Amanda. "PEX1 Mutations in Australasian Patients with Disorders of Peroxisome Biogenesis". Thesis, Griffith University, 2004. http://hdl.handle.net/10072/366184.
Texto completoResumen
The peroxisome is a subcellular organelle that carries out a diverse range of metabolic functions, including the b-oxidation of very long chain fatty acids, the breakdown of peroxide and the a-oxidation of fatty acids. Disruption of peroxisome metabolic functions leads to severe disease in humans. These diseases can be broadly grouped into two categories: those in which a single enzyme is defective, and those known as the peroxisome biogenesis disorders (PBDs), which result from a generalised failure to import peroxisomal matrix proteins (and consequently result in disruption of multiple metabolic pathways). The PBDs result from mutations in PEX genes, which encode protein products called peroxins, required for the normal biogenesis of the peroxisome. PEX1 encodes an AAA ATPase that is essential for peroxisome biogenesis, and mutations in PEX1 are the most common cause of PBDs worldwide. This study focused on the identification of mutations in PEX1 in an Australasian cohort of PBD patients, and the impact of these mutations on PEX1 function. As a result of the studies presented in this thesis, twelve mutations in PEX1 were identified in the Australasian cohort of patients. The identified mutations can be broadly grouped into three categories: missense mutations, mutations directly introducing a premature termination codon (PTC) and mutations that interrupt the reading frame of PEX1. The missense mutations that were identified were R798G, G843D, I989T and R998Q; all of these mutations affect amino acid residues located in the AAA domains of the PEX1 protein. Two mutations that directly introduce PTCs into the PEX1 transcript (R790X and R998X), and four frameshift mutations (A302fs, I370fs, I700fs and S797fs) were identified. There was also one mutation found in an intronic region (IVS22-19A>G) that is presumed to affect splicing of the PEX1 mRNA. Three of these mutations, G843D, I700fs and G973fs, were found at high frequency in this patient cohort. At the commencement of these studies, it was hypothesised that missense mutations would result in attenuation of PEX1 function, but mutations that introduced PTCs, either directly or indirectly, would have a deleterious effect on PEX1 function. Mutations introducing PTCs are thought to cause mRNA to be degraded by the nonsense-mediated decay of mRNA (NMD) pathway, and thus result in a decrease in PEX1 protein levels. The studies on the cellular impact of the identified PEX1 mutations were consistent with these hypotheses. Missense mutations were found to reduce peroxisomal protein import and PEX1 protein levels, but a residual level of function remained. PTC-generating mutations were found to have a major impact on PEX1 function, with PEX1 mRNA and protein levels being drastically reduced, and peroxisomal protein import capability abolished. Patients with two missense mutations showed the least impact on PEX1 function, patients with two PTC-generating mutations had a severe defect in PEX1 function, and patients carrying a combination of a missense mutation and a PTC-generating mutation showed levels of PEX1 function that were intermediate between these extremes. Thus, a correlation between PEX1 genotype and phenotype was defined for the Australasian cohort of patients investigated in these studies. For a number of patients, mutations in the coding sequence of one PEX1 allele could not be identified. Analysis of the 5' UTR of this gene was therefore pursued for potential novel mutations. The initial analyses demonstrated that the 5' end of PEX1 extended further than previously reported. Two co-segregating polymorphisms were also identified, termed –137 T>C and –53C>G. The -137T>C polymorphism resided in an upstream, in-frame ATG (termed ATG1), and the possibility that the additional sequence represented PEX1 coding sequence was examined. While both ATGs were found to be functional by virtue of in vitro and in vivo expression investigations, Western blot analysis of the PEX1 protein in patient and control cell extracts indicated that physiological translation of PEX1 was from the second ATG only. Using a luciferase reporter approach, the additional sequence was found to exhibit promoter activity. When examined alone the -137T>C polymorphism exerted a detrimental effect on PEX1 promoter activity, reducing activity to half that of wild-type levels, and the -53C>G polymorphism increased PEX1 promoter activity by 25%. When co-expressed (mimicking the physiological condition) these polymorphisms compensated for each other to bring PEX1 promoter activity to near wild-type levels. The PEX1 mutations identified in this study have been utilised by collaborators at the National Referral Laboratory for Lysosomal, Peroxisomal and Related Genetic Disorders (based at the Women's and Children's Hospital, Adelaide), in prenatal diagnosis of the PBDs. In addition, the identification of three common mutations in Australasian PBD patients has led to the implementation of screening for these mutations in newly referred patients, often enabling a precise diagnosis of a PBD to be made. Finally, the strong correlation between genotype and phenotype for the patient cohort investigated as part of these studies has generated a basis for the assessment of newly identified mutations in PEX1.Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Biomolecular and Biomedical Sciences
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Sawyer, Rosalind Mary. "Isolation of a vicilin gene from pea (Pisum sativum L.), and nuclease sensitivity of seed storage protein genes in pea chromatin". Thesis, Durham University, 1986. http://etheses.dur.ac.uk/6873/.
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A library of pea genomic DNA in the bacteriophage vector EMBL3 was screened by hybridisation to cDNAs encoding vicilin, a major storage protein of pea (Pisum sativum L.) seeds. A vicilin gene, vic A, was isolated and characterised by restriction mapping and DNA sequencing. The nucleotide and predicted amino acid sequences of vic A were compared to those of vicilin cDNAs, and the gene was found to encode a 50,000M(_r) non-glycosylated vicilin subunit that does not undergo post-translational proteolytic cleavage. The introns in vic A were typical of those in plant genes, being small and high in A+T content, and the nucleotide sequences at the splice sites showed good homology to the plant consensus. The positions of the introns in vic A were similar to those in a gene encoding a subunit of phaseolin, a related protein from French bean (Phaseolus vulgaris). Methods were developed for the analysis of nuclease sensitivity of specific genes in pea chromatin. The DNAase I sensitivity of the seed storage protein genes was found to be greater in developing cotyledons, where the genes were transcriptionally active, than in leaves, where they were inactive. The pea ribosomal genes showed relative resistance to DNAase I in both tissues. The nucleosome repeat length, determined by digestion of chromatin with micrococcal nuclease, was similar in both tissues. No evidence was obtained for DNAase I hypersensitive sites in pea chromatin. This result supports the findings of two other studies, and suggests that such sites are absent from plant chromatin.
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Liu, Xiaoguang. "Characterization of the pea pathogenicity (PEP) gene cluster in the fungal pathogen Nectria haematococca". Diss., The University of Arizona, 2002. http://hdl.handle.net/10150/279972.
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The fungus Nectria haematococca is a broad host range pathogen. Isolates pathogenic on pea are able to detoxify the phytoalexin pisatin using the enzyme pisatin demethylase. When the gene (PDA1 ) encoding this enzyme was mutated via gene disruption, the mutants were less virulent but still pathogenic on pea. Additional studies demonstrated that PDA1 was on a 1.6-Mb conditionally dispensable (CD) chromosome and that loss of this CD chromosome resulted in the complete loss of pea pathogenicity. This leads to the hypothesis that there are other pea p̱athogenicity (PEP) genes in addition to the PDA1 gene on the CD chromosome. One of the major goals of this work was to test this hypothesis by isolating and characterizing these PEP genes. The results identified three novel PEP genes: PEP1, PEP2, and PEP5, each of which can confer disease-causing ability independently when introduced into a nonpathogenic isolate lacking the CD chromosome. The predicted product of PEP5 is related to members of the major facilitator superfamily, including proton-dependent multidrug export systems, and the predicted product of PEP2 contains conserved RNA-binding motifs. PEP1 shows no significant similarity to any known gene in the public databases. The three PEP genes and PDA1 are organized into a functional cluster, termed the PEP cluster, within 25 kb that conditions full pathogenicity on pea. The PEP cluster contains two additional genes, cDNA3 and cDNA4, and neither gene by itself is able to confer disease-causing abilities. The open reading frame (ORF) for cDNA3 gene is small. The predicted cDNA4 product exhibits significant similarities to the transposon impala of Fusarium oxysporum. The sequences of other portions of the PEP cluster predict four ORFs showing strong similarities to other fungal transposases. Several features of the PEP cluster, such as possession of multiple virulence genes, presence of DNA mobile elements, and differences in both codon usage and G+C content compared with other portions of the genome, resemble those of the pathogenicity islands identified in plant and animal bacterial pathogens. These properties raise the possibility that the PEP gene cluster may represent a fungal pathogenicity island. The second major goal of my work was to quantify the expression of PDA1, PEP1, PEP2, and PEP5 in vitro and in planta, and to characterize the regions flanking the PEP cluster. A real-time quantitative RT-PCR approach was used to measure the mRNA levels of these pathogenicity genes. In a glucose-based growth medium, mRNA levels of PDA1, PEP1, PEP5 were very low, while expression of PEP2 was undetectable. Starvation in vitro strongly stimulated PDA1 gene expression, whereas expression of PEP1 and PEP5 increased only moderately. In contrast, starvation had no effect on expression of PEP2 as indicated by an undetectable mRNA level during the 12 hr time course tested. In vitro pisatin strongly induced the expression of all four pathogenicity genes and the PDA1 experienced the highest level of induction (∼300-fold increase). Finally, marked induction of PDA1, PEP1 and PEP2 was observed during infection of pea roots, whereas the expression of PEP5 was only moderately induced. The flanking regions of the PEP cluster were sequenced and the sequences predict six ORFs that display significant similarities to various fungal genes. The G+C content, gene density, and codon preference of the PEP cluster and its flanking regions are similar. All six of the predicted genes in the flanking regions of the PEP cluster are expressed during infection of pea.
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Ferreira, Briana Cardoso. "Prospecção de genes pif (per os infectivity factor) em variantes genotípicos de Anticarsia gemmatalis MNPV e construção de recombinante com interrupção do gene pif-1". reponame:Repositório Institucional da UnB, 2008. http://repositorio.unb.br/handle/10482/2610.
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Os baculovirus são vírus patogênicos a insetos, principalmente aos da ordem Lepidoptera. É comum o aparecimento de mutantes defectivos em populações de campo, com ausência de genes essenciais, que são mantidos pela co-infecção de células por diferentes genótipos virais. Esses genótipos quando purificados podem perder a capacidade de infectar a larva hospedeira, devido a deleções em genes pif (per os infectivity factor), essenciais para a infecção por via oral. Sabe-se que as proteínas PIF estão associadas ao envelope da partícula ODV, necessária para o estabelecimento da infecção primária no inseto. O genoma do Anticarsia gemmatalis multiple nucleopolyhedrovirus (AgMNPV) foi recentemente seqüenciado sendo então relatada a presença dos genes pif-1 e pif-2 no vírus. Neste trabalho, genótipos de AgMNPV derivados do isolado de campo AgMNPV-79 foram selecionados e, através de análise de perfil de restrição do DNA viral, foi confirmada a existência de variantes genotípicos na população. Para a investigação da possível presença de mutantes defectivos, amplificações das regiões de pif-1 e pif-2 por PCR foram realizadas em cada variante sendo que todos os clones da população apresentaram amplificações dos dois genes. Todos os clones mostraram-se altamente infecciosos por ingestão oral, porém o genótipo Ag79-01 apresentou maior virulência entre eles. A presença de um terceiro gene pif (pif-3) foi identificada recentemente no genoma do Autographa californica multiple nucleopolyhedrovirus (AcMNPV). Da mesma forma, esse gene é também essencial para o estabelecimento da infecção primária por via oral. Por análise de BLAST o gene foi então identificado como a ORF 114 do genoma do vírus AgMNPV, a qual apresentou uma identidade de aminoácidos de 67% com a ORF do vírus AcMNPV. Com base nessa informação, primers para o gene pif-3 foram desenhados e amostras de DNA dos diferentes genótipos virais foram submetidas a amplificações por PCR. Novamente todos os clones virais apresentaram amplificação de um fragmento correspondente à região de pif-3. Uma vez que os genes pif estavam presentes em todos os variantes genotípicos analisados, foi elaborada uma estratégia para a construção de um vírus recombinante com deleção do gene pif-1, visando o estudo de seu papel na infecção oral do inseto. O vírus recombinante vAgGFP?pif-1, obtido por recombinação homóloga, teve o gene pif-1 substituído por um cassete gênico contendo um gene repórter (gfp) sob comando do promotor constitutivo hsp70. Esse vírus foi selecionado a partir da visualização de células infectadas emitindo fluorescência, devido à expressão da proteína GFP. O vírus vAgGFP?pif-1 encontra-se sob processo de purificação.
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Harris, Robert. "The regulation of the embryonic transcription factor Pax-3". Thesis, University of Southampton, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.342629.
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Zasiura, Colette. "Characterisation and expression of pea lipoxygenase genes". Thesis, University of East Anglia, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.365059.
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Wright, David. "The role of pax genes in vertebrate segmentation". Thesis, University of Dundee, 2010. https://discovery.dundee.ac.uk/en/studentTheses/15d5c38e-b000-4dcb-be35-49a46feb4664.
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Pax genes are involved in a range of processes in the developing embryo. Pax3 and Pax7 in particular are associated with the paraxial mesoderm, especially the development of the myogenic lineage. However, recent studies have suggested that Pax3 and Pax7 may have earlier, morphogenetic roles in the segementation of the paraxial mesoderm. Here we examine the expression of Pax3 and Pax7 in the chicken presomitic mesoderm, and investigate their function using an in ovo electroporation transfection technique. We find that Pax3/7 drives precocious differentiation of PSM towards the myogenic lineage, as well as inducing a range of morphological changes in PSM tissue. These changes include alterations in the cytoskeleton, cell adhesion, and extracellular matrix formation.
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Garrett, Christine. "Functional mapping of pea legumin upstream regulatory elements using TI plasmid vectors". Thesis, Durham University, 1991. http://etheses.dur.ac.uk/6041/.
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The leg A gene from Pisum sativum L. has been extensively characterised and a distinct pattern of developmental and organ-specific gene expression demonstrated. Homology between legumin genes from other species has given some indication of those sequences which may be responsible for the regulation at the level of transcription. This study was designed to provide a functional analysis of the upstream sequences. A number of plasmid vectors containing a maximum of 1.2 kb of upstream sequence from the leg A gene of Pisum sativum I., ligated to the coding region of the nopaline synthase (nos) gene, were constructed. The use of smaller promoter fragments and the insertion of spacer DNA within the promoter region was employed in an effort to localise the regions of 5' flanking sequence which may play a role in tissue specific expression. In a minority of tumours derived from tissue transformed with the vector containing the ' full-length ' leg A promoter, low levels of nopaline were detected, but not with those containing a shorter promoter fragment. Results from the analysis of Seed tissue indicates that 800 bp of the leg A promoter was insufficient to direct tissue-specific expression of the fused nopaline synthase gene in transgenic Nicotiana tabacum, although one individual plant showed a constitutive pattern of nopaline synthesis. However, published results obtained with legumin and other storage protein gene promoters would suggest that this promoter fragment should have been sufficient to confer seed-specific expression. This suggests that there may have been undesirable secondary structures, or small undetected rearrangements, introduced during the construction of the transcriptional fusions between leg A and nos. Alternatively the marker gene may be inadequately sensitive to permit detection of low levels of expression.
Libros sobre el tema "PEX genes"
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Clark, Ellena J. Studies on cloned genes of pea powdery mildew (Erysiphe pisi DC). Birmingham: University of Birmingham, 1997.
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L' incesto multiforme: Per una teoria sulla genesi del "disturbo psichico". Milano: Giuffrè, 1985.
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F. H. Bradley e la genesi della filosofia analitica: Contributi per una definizione. Milano: UNICOPLI, 2007.
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Grassi, Andrea Massimo. Fräulein Klarinette: La genesi e il testo delle opere per clarinetto di Johannes Brahms. Pisa: ETS, 2006.
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Genesi e storia del Popolo della libertà: Quale futuro per un partito unico del centrodestra. Soveria Mannelli: Rubbettino, 2012.
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Cavina, Marco. Il duello giudiziario per punto d'onore: Genesi, apogeo e crisi nell'elaborazione dottrinale italiana (sec. XIV-XVI). Torino: G. Giappichelli, 2003.
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Fericgla, Josep M. El bolet i la genesi de les cultures: Gnoms i follets, ambits culturals forjats per l'Amanita muscaria. Barcelona: Editorial Alta Fulla, 1991.
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Maffei, Paola y Gian Maria Varanini, eds. Honos alit artes. Studi per il settantesimo compleanno di Mario Ascheri. I. La formazione del diritto comune. Florence: Firenze University Press, 2015. http://dx.doi.org/10.36253/978-88-6655-627-5.
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The articles collected in the book offer insights on major aspects that determined the success and development of the ”ius commune”, progressively spread out across Europe, and from Europe to those parts of the world that felt the influence. Three prospects are hereby taken onto account, in a time span of seven centuries (XII-XVIII): the consilia of Jurists, the training paths in universities (texts, literary genres, doctrines, teaching and teachers) and the canonical science.
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Alibert, Loïs. La correspondència entre Loïs Alibert i Josep Carbonell i Gener: Materials per a l'estudi de la codificació de la llengua occitana. Editado por Carbonell i Gener, Josep, d. 1979. y Alquézar i. Montañés Manuel. Barcelona: Institut d'Estudis Catalans, 1992.
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Bartolo, Giuseppe. Genesi e sviluppo di una nuova politica per il Mezzogiorno: Bibliografia ragionata della stampa quotidiana e periodica negli anni 1943-54. Galatina: Congedo, 1992.
Buscar texto completoCapítulos de libros sobre el tema "PEX genes"
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Charlton, Wayne y Eduardo Lopez-Huertas. "PEX Genes in Plants and Other Organisms". En Plant Peroxisomes, 385–426. Dordrecht: Springer Netherlands, 2002. http://dx.doi.org/10.1007/978-94-015-9858-3_12.
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Sheikh, Ahmad Y. y Joseph C. Wu. "Evaluating Gene and Cell Therapy". En Cardiac PET and PET/CT Imaging, 373–93. New York, NY: Springer New York, 2007. http://dx.doi.org/10.1007/978-0-387-38295-1_25.
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McPhee, K. E., S. Gollasch, H. E. Schroeder y T. J. V. Higgins. "Gene Technology in Pea". En Transgenic Crops of the World, 351–59. Dordrecht: Springer Netherlands, 2004. http://dx.doi.org/10.1007/978-1-4020-2333-0_26.
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Jacobs, A. H. y W. D. Heiss. "Small-Animal PET in Neuro-oncology and Gene Therapy". En PET and PET-CT in Oncology, 87–97. Berlin, Heidelberg: Springer Berlin Heidelberg, 2004. http://dx.doi.org/10.1007/978-3-642-18803-9_10.
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Haberkorn, U. "Monitoring of gene therapy with PET". En PET in Clinical Oncology, 397–410. Heidelberg: Steinkopff, 2000. http://dx.doi.org/10.1007/978-3-642-57703-1_31.
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Abe, Tomoko, Hiroyuki Ichida, Yoriko Hayashi, Ryouhei Morita, Yuki Shirakawa, Kotaro Ishii, Tadashi Sato, Hiroki Saito y Yutaka Okumoto. "Ion beam mutagenesis - an innovative and effective method for plant breeding and gene discovery." En 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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Tremblay, Patrick, Susanne Dietrich, Anastasia Stoykova, Edward T. Stuart y Peter Gruss. "Pax Genes as Pleiotropic Regulators of Embryonic Development". En Neural Cell Specification, 29–50. Boston, MA: Springer US, 1995. http://dx.doi.org/10.1007/978-1-4615-1929-4_3.
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Gerrish, Kevin, Susan Samaras, Michelle A. Cissell, Christopher V. E. Wright y Roland Stein. "Regulation of pdx-1 Gene Expression". En Molecular Basis of Pancreas Development and Function, 275–87. Boston, MA: Springer US, 2001. http://dx.doi.org/10.1007/978-1-4615-1669-9_16.
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Singh, Ishwar, Krishan Kumar, Prabha Singh, Pranjal Yadava y Sujay Rakshit. "Physiological and molecular interventions for improving nitrogen-use efficiency in maize." En Molecular breeding in wheat, maize and sorghum: strategies for improving abiotic stress tolerance and yield, 325–39. Wallingford: CABI, 2021. http://dx.doi.org/10.1079/9781789245431.0019.
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Abstract This chapter discusses (i) the importance of nitrogen in plant growth and development, (ii) what is nitrogen-use efficiency (NUE) and how to manage it, (iii) traits influencing nitrogen-uptake efficiency including root system architecture, root nitrogen transporter system, and interaction with microorganisms, (iv) traits influencing nitrogen-utilization efficiency, such as nitrate assimilation, canopy photosynthesis per unit of nitrogen, (v) identification and use of quantitative trait loci (QTLs) related to NUE, (vi) identification of nitrogen-responsive genes, and (vii) nitrogen signalling and transduction for improving NUE. Intensive research on molecular and genetic aspects of NUE has led to the identification of many new genes, QTLs and alleles that could be deployed to develop new genotypes. The future direction of the research efforts should be towards understanding the interaction of NUE-related genes with cellular small RNA flux and perturbing the system performance through metabolic engineering and genome editing techniques.
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Goulding, Martyn y Alice Paquette. "Pax Genes and Neural Tube Defects in the Mouse". En Ciba Foundation Symposium 181 - Neural Tube Defects, 103–17. Chichester, UK: John Wiley & Sons, Ltd., 2007. http://dx.doi.org/10.1002/9780470514559.ch7.
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Souza, Sabrina Pires Maciel de, JULIANA ECHEVARRIA LIMA y RENATA MEIRELLES PEREIRA. "LINFÓCITOS INFECTADOS PELO HTLV-1 INDUZEM A DIFERENCIAÇÃO DE MONÓCITOS EM MACRÓFAGOS \"M1-LIKE\" IN VITRO". En II Congresso Brasileiro de Imunologia On-line. Revista Multidisciplinar em Saúde, 2022. http://dx.doi.org/10.51161/ii-conbrai/5788.
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Introdução: O vírus linfotrópico para células T humanas do tipo 1 (HTLV-1) é um retrovírus associado à leucemia/linfoma de células T e à mielopatia/paraparesia espástica tropical (MAH/PET). A MAH/PET é uma doença inflamatória crônica, caracterizada pela infiltração de leucócitos na medula espinhal e neurodegeneração. Embora os linfócitos T sejam o principal alvo do HTLV-1, células como monócitos também podem ser infectadas. Monócitos de indivíduos infectados pelo HTLV-1 apresentam importantes alterações funcionais quando comparados com células de doadores não infectados. O presente estudo caracterizou o perfil de monócitos durante a infecção pelo HTLV-1 utilizando células de linhagem THP-1 como modelo. Metodologia: Co-cultivamos células THP-1 com linhagens de linfócitos transformados pelo HTLV-1 (MT2) afim de elucidar a relação do contato célula-célula e/ou fatores secretados pelas células infectadas na resposta e diferenciação de monócitos. Resultados: Observamos que as células THP-1 adquiriram características similares a macrófagos baseado na morfologia e expressão de CD68, além da expressão das moléculas de superfície HLA-DR, CD80 e CD86, bem como de genes pró-inflamatórios (TNF, IL6 e IL1B) e secreção de citocinas (TNF-α and IL-6) após o co-cultivo com a MT2. Entretanto, não houve aumento da expressão de ARG (gene codificante para Arginase) e TGFB1, característicos de macrófagos M2. A presença da MT2 na cultura também induziu a expressão de TLR4, TLR2 e MD2, relacionados com ativação celular. Além disso, observamos aumento na regulação de genes estimulados pelo Interferon (IFNB1, OASL e ISG15), corroborando com o estado de infecção viral. Esses resultados, em conjunto com a detecção do gene viral Tax, sugere a infecção das células THP-1 pelo HTLV-1 após o co-cultivo. Tais efeitos ocorreram independente de contato, conforme observado nos ensaios utilizando sistema transwell. Conclusão: Nossos resultados sugerem que após o co-cultivo com células infectadas pelo HTLV-1, monócitos THP-1 foram capazes de se diferenciar em um fenótipo compatível com o perfil de macrófagos M1 in vitro e induziu a expressão de genes associados à resposta inflamatória e anti-viral em um sistema independente do contato célula-célula. Esses achados podem auxiliar no entendimento da resposta protetora e patológica mediada por monócitos e macrófagos durante a infecção pelo HTLV-1.
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Zorin, E. A., O. A. Kulaeva, O. Y. Shtark y V. A. Zhukov. "Regulation of development of arbuscular-mycorrhizal symbiosis by alternative splicing in garden pea (Pisum sativum L.)". En 2nd International Scientific Conference "Plants and Microbes: the Future of Biotechnology". PLAMIC2020 Organizing committee, 2020. http://dx.doi.org/10.28983/plamic2020.291.
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Klimenko, O. P., O. A. Kulaeva, O. Y. Shtark, A. I. Zhernakov, I. A. Tikhonovich y V. A. Zhukov. "Genetic characterization of pea (Pisum sativum L.) mutants P59 and P60, defective in nitrogen fixation". En 2nd International Scientific Conference "Plants and Microbes: the Future of Biotechnology". PLAMIC2020 Organizing committee, 2020. http://dx.doi.org/10.28983/plamic2020.122.
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Several genes involved in development of symbiosis between pea and rhizobia haven’t yet been characterized in detail. Here, the first results of genetic analysis of pea mutants in the symbiotic genes Sym23 and Sym24 are presented.
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Reitsma, P. H., A. M. Riemens, R. M. Bertina y E. Briít. "PROMOTOR MUTATIONS IN A PATIENT WITH HAEMOPHILIA B LEYDEN". En XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1643870.
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Haemophilia B Leyden is characterized by low levels of factor IX antigen and activity before the age of 15, whereas after puberty factor IX levels rise at a rate of about 4-5% per year. To date such a genetic variant of factor IX synthesis has been reported in two (probably related) Dutch families, in a Greek and in an American family of Armenian descent. Laboratory and clinical investigations indicate that the factor IX protein is normal but that the regulation of factor IX synthesis has come under the control of the steroid hormone testosterone. We have started to investigate the factor IX gene in a patient from a Dutch family in an attempt to explain the aberrant regulation.Southern blotting revealed no gross deletions or insertions in the factor IX gene. Therefore the promotor region of the factor IX gene was cloned and subjected to a detailed restriction enzyme analysis. This also did not indicate that significant DNA deletions or insertions had occurred. Subsequently we established the nucleotide sequence of the DNA surrounding the first exon which encompassed about 600 basepairs of the promotor region. Two deviations from previously published sequence data were recorded. Firstly, an A T change was noted in the presumed "tata" box region 20 basepairs upstream from the start site of mRNA synthesis. Secondly, at position −423 a T C change was found which lies 13 basepairs upstream from a potential alternative "tata" box.The point mutation at position −20 might well explain the failure of gene expression during the prepuberal stage of the disease. Whether the same point mutation also leads to the testosterone effects or that a second sequence variation is a prerequisite for this phenomenon remains to be established from studies on the promotor region in representatives of the Greek and American families. Eventually the introduction of chaemeric genes, containing the various promotor regions, into testosterone responsive cells should delineate the promotor sequences responsible for the variations in factor IX gene expression.
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Dyment, Nathaniel A., Namdar Kazemi, Lindsey E. Aschbacher-Smith, Nicolas J. Barthelery, Keith Kenter, Cynthia Gooch, Jason T. Shearn, Christopher Wylie y David L. Butler. "The Relationships Among Spatiotemporal Gene Expression, Histology, and Biomechanics Following Full-Length Injury in the Murine Patellar Tendon". En ASME 2011 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2011. http://dx.doi.org/10.1115/sbc2011-53622.
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Tendon and ligament injuries present a considerable socioeconomic impact as close to 50% of the 32 million musculoskeletal injuries in the US per year include these structures [1]. The inadequate healing in these tissues requires novel treatment modalities. Improving tendon tissue engineering dictates that we better understand the process of natural adult tendon healing. Type-I (Col1) and Type-II (Col2) collagens are important structural proteins in tendon as Col1 is the main collagen type found in the tendon midsubstance while Col2 is expressed at the insertion into bone during development, growth, and healing [2–3]. Expression of Col1 and Col2 has typically been analyzed via qPCR, western blotting, and immunohistochemistry (IHC) during healing. However, the temporal expression of these genes is still poorly understood on a cell-by-cell basis. Our lab has previously studied patellar tendon (PT) healing in NZW rabbits [4]. While the NZW rabbit allows for controlled injuries and accurate biomechanical assessment of healing, it lacks the genetic power that is offered in the mouse. Therefore, pOBCo13.6GFPtpz (Col1) and pCol2ECFP (Col2) double transgenic (DT) reporter mice were created to track spatiotemporal gene expression. Thus, the objectives of this study were to monitor changes in: 1) spatiotemporal Col1 and Col2 gene expression patterns, 2) tissue morphology, and 3) healing biomechanics following a full-length, central PT injury in Col1/Col2 DT mice and to compare these natural healing results to contralateral surgical shams and normal PT in age-matched controls.
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Rudaya, E. S. y E. A. Dolgikh. "Production and analysis of tomato Solanum lycopersicum composite plants carrying the genes of pea Pisum sativum receptors to rhizobial signaling molecules". En 2nd International Scientific Conference "Plants and Microbes: the Future of Biotechnology". PLAMIC2020 Organizing committee, 2020. http://dx.doi.org/10.28983/plamic2020.208.
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House, R., A. Watt y J. M. Williams. "The Professional Engineering Genres (PEG) Project". En IEEE International Professional Communication Conference, 2003. IPCC 2003. Proceedings. IEEE, 2003. http://dx.doi.org/10.1109/ipcc.2003.1245493.
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Jimenez, Ray Duenas, David Correa Martins y Carlos Silva Santos. "Gene Networks Inference through One Genetic Algorithm Per Gene". En 2014 14th IEEE International Conference on Bioinformatics and Bioengineering (BIBE). IEEE, 2014. http://dx.doi.org/10.1109/bibe.2014.9.
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Дягилева, А., Лидия Туманова, Валентин Митин y Кристина Грэждиеру. "Идентификация Fusarium spp. и Alternaria spp. в семенах некоторых овощных культур". En VIIth International Scientific Conference “Genetics, Physiology and Plant Breeding”. Institute of Genetics, Physiology and Plant Protection, Republic of Moldova, 2021. http://dx.doi.org/10.53040/gppb7.2021.10.
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In this paper the results of molecular diagnostics of Fusarium spp. and Alternaria spp. in bell pep-per and eggplant seeds of local genotypes at different time points of storage are presented. The diagnos-tics was effectuated using nested-PCR protocol with genus-specific and species-specific primers to F. ox-ysporum, F. solani, F. nivale, F. equiseti, F. culmorum, F. verticillioides, F. avenaceum, A. alternata, and A. solani. In the samples of studied bell pepper and eggplant genotypes A. alternata was found. In egg-plant seeds certain species of Fusarium spp. were identified.
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Vasileva, E. N., A. M. Afonin, G. A. Akhtemova, V. A. Zhukov y I. A. Tikhonovich. "Endophytic bacteria isolated from garden pea (Pisum sativum L.)". En 2nd International Scientific Conference "Plants and Microbes: the Future of Biotechnology". PLAMIC2020 Organizing committee, 2020. http://dx.doi.org/10.28983/plamic2020.265.
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Endophytic bacteria were isolated from surface-sterilized aerial parts of pea. Taxonomic status of isolated strains was determined by sequencing of 16S rRNA gene. Moreover, genomes of growth-promoting endophytes were sequenced.
Informes sobre el tema "PEX genes"
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Gambhir, Sanjiv S. New Gene Based Probes for Imaging Breast Cancer with PET. Fort Belvoir, VA: Defense Technical Information Center, agosto de 2001. http://dx.doi.org/10.21236/ada399369.
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Gambhir, Senjiv S. New Gene Based Probes for Imaging Breast Cancer with PET. Fort Belvoir, VA: Defense Technical Information Center, agosto de 1999. http://dx.doi.org/10.21236/ada391321.
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Gambhir, Sanjiv. New Gene Based Probes for Imaging Breast Cancer with PET. Fort Belvoir, VA: Defense Technical Information Center, agosto de 2000. http://dx.doi.org/10.21236/ada393157.
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Reisch, Bruce, Avichai Perl, Julie Kikkert, Ruth Ben-Arie y Rachel Gollop. Use of Anti-Fungal Gene Synergisms for Improved Foliar and Fruit Disease Tolerance in Transgenic Grapes. United States Department of Agriculture, agosto de 2002. http://dx.doi.org/10.32747/2002.7575292.bard.
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Original objectives . 1. Test anti-fungal gene products for activity against Uncinula necator, Aspergillus niger, Rhizopus stolonifer and Botrytis cinerea. 2. For Agrobacterium transformation, design appropriate vectors with gene combinations. 3. Use biolistic bombardment and Agrobacterium for transformation of important cultivars. 4. Characterize gene expression in transformants, as well as level of powdery mildew and Botrytis resistance in foliage of transformed plants. Background The production of new grape cultivars by conventional breeding is a complex and time-consuming process. Transferring individual traits via single genes into elite cultivars was proposed as a viable strategy, especially for vegetatively propagated crops such as grapevines. The availability of effective genetic transformation procedures, the existence of genes able to reduce pathogen stress, and improved in vitro culture methods for grapes, were combined to serve the objective of this proposal. Effective deployment of resistance genes would reduce production costs and increase crop quality, and several such genes and combinations were used in this project. Progress The efficacy of two-way combinations of Trichoderma endochitinase (CHIT42), synthetic peptide ESF12 and resveratrol upon the control of growth of Botrytis cinerea and Penicillium digitatum were evaluated in vitro. All pairwise interactions were additive but not synergistic. Per objective 2, suitable vectors with important gene combinations for Agrobacterium transformation were designed. In addition, multiple gene co-transformation by particle bombardment was also tested successfully. In New York, transformation work focused on cultivars Chardonnay and Merlot, while the technology in Israel was extended to 41B, R. 110, Prime, Italia, Gamay, Chardonnay and Velika. Transgenic plant production is summarized in the appendix. Among plants developed in Israel, endochitinase expression was assayed via the MuchT assay using material just 1-5 days after co-cultivation. Plants of cv. Sugraone carrying the gene coding for ESF12, a short anti-fungal lytic peptide under the control of the double 358 promoter, were produced. Leaf extracts of two plants showed inhibition zones that developed within 48 h indicating the inhibitory effect of the leaf extracts on the six species of bacteria. X fastidiosa, the causal organism of Pierce's disease, was very sensitive to leaf extracts from ESF12 transformed plants. Further work is needed to verify the agricultural utility of ESF12 transformants. In New York, some transformants were resistant to powdery mildew and Botrytis fruit rot. Major conclusions, solutions, achievements and implications The following scientific achievements resulted from this cooperative BARD project: 1. Development and improvement of embryogenesis and tissue culture manipulation in grape, while extending these procedures to several agriculturally important cultivars both in Israel and USA. 2. Development and improvement of novel transformation procedures while developing transformation techniques for grape and other recalcitrant species. 3. Production of transgenic grapevines, characterization of transformed vines while studying the expression patterns of a marker gene under the control of different promoter as the 35S CaMV in different part of the plants including flowers and fruits. 4. Expression of anti-fungal genes in grape: establishment of transgenic plants and evaluation of gene expression. Development of techniques to insert multiple genes. 5. Isolation of novel grape specific promoter to control the expression of future antimicrobial genes. It is of great importance to report that significant progress was made in not only the development of transgenic grapevines, but also in the evaluation of their potential for increased resistance to disease as compared with the non engineered cultivar. In several cases, increased disease resistance was observed. More research and development is still needed before a product can be commercialized, yet our project lays a framework for further investigations.
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Tigyi, Gabor. Novel Methods for Imaging PET Biomarkers and Gene Therapy of Cancer. Fort Belvoir, VA: Defense Technical Information Center, mayo de 2008. http://dx.doi.org/10.21236/ada485839.
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Tigyi, Gabor, David Townsend, Lorraine Albritton, Lawrence Pfeffer, Jonathan Wall, Stephen Kennel y Yuko Fujiwara. Novel Methods for Imaging PET Biomarkers and Gene Therapy of Cancer. Fort Belvoir, VA: Defense Technical Information Center, mayo de 2009. http://dx.doi.org/10.21236/ada625277.
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Grumet, Rebecca, Rafael Perl-Treves y Jack Staub. Ethylene Mediated Regulation of Cucumis Reproduction - from Sex Expression to Fruit Set. United States Department of Agriculture, febrero de 2010. http://dx.doi.org/10.32747/2010.7696533.bard.
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Reproductive development is a critical determinant of agricultural yield. For species with unisexual flowers, floral secualdifferentation adds additional complexity, that can influenec productivity. The hormone ethylene has long, been known to play a primary role in sex determination in the Cucumis species cucumber (C. sativus) and melon (C. melo). Our objectives were to: (1) Determine critical sites of ethylene production and perception for sex determination; (2) Identify additional ethylene related genes associated with sex expression; and (3) Examine the role of environment ami prior fruit set on sex expression, pistillate flower maturation, and fruit set. We made progress in each of these areas. (1) Transgenic melon produced with the Arabidopsis dominant negative ethylene perception mutant gene, etrl-1, under the control of floral primordia targeted promoters [AP3 (petal and stamen) and CRC (carpel and nectary)], showed that ethylene perception by the stamen primordia, rather than carpel primordia, is critical for carpel development at the time of sex determination. Transgenic melons also were produced with the ethylene production enzyme gene. ACS, encoding l-aminocyclopropane-lcarboylate synthase, fused to the AP3 or CRC promoters. Consistent with the etr1-1 results, CRC::ACS did not increase femaleness; however, AP3::ACS reduced or eliminated male flower production. The effects of AP3:ACS were stronger than those of 35S::ACS plants, demonstratin g the importance of targeted expression, while avoiding disadvantages of constitutive ethylene production. (2) Linkage analysis coupled with SNP discovery was per formed on ethylene and floral development genes in cucumber populations segregating for the three major sex genes. A break-through towards cloning the cucumber M gene occurred when the melon andromonoecious gene (a), an ACS gene, was cloned in 2008. Both cucumber M and melon a suppress stamen development in pistillate flowers. We hypothesized that cucumber M could be orthologous to melon a, and found that mutations in CsACS2 co-segregated perfectly with the M gene. We also sought to identify miRNA molecules associated with sex determination. miRNA159, whose target in Arabidopsis is GAMYB[a transcription factor gene mediating response to10 gibberellin (GA)], was more highly expressed in young female buds than male. Since GA promotes maleness in cucumber, a micro RNA that counteracts GAMYB could promote femaleness. miRNA157, which in other plants targets transcription factors involved in flower development , was expressed in young male buds and mature flower anthers. (3) Gene expression profiling showed that ethylene-, senescence-, stress- and ubiquitin-related genes were up-regulated in senescing and inhibited fruits, while those undergoing successful fruit set up-regulated photosynthesis, respiration and metabolic genes. Melon plants can change sex expression in response to environmental conditions, leading to changes in yield potential. Unique melon lines with varying sex expression were developed and evaluated in the field in Hancock, Wisconsin . Environmental changes during the growing season influenced sex expression in highly inbred melon lines. Collectively these results are of significance for understanding regulation of sex expression. The fact that both cucumber sex loci identified so far (F and M) encode isoforms of the same ethylene synthesis enzyme, underscores the importance of ethylene as the main sex determining hormone in cucumber. The targeting studies give insight into developmental switch points and suggest a means to develop lines with earlier carpel-bearing flower production and fruit set. These results are of significance for understanding regulation of sex expression to facilitate shorter growing seasons and earlier time to market. Field results provide information for development of management strategies for commercial production of melon cultivars with different sex expression characteristics during fruit production.
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Prusky, Dov, Nancy P. Keller y Amir Sherman. global regulation of mycotoxin accumulation during pathogenicity of Penicillium expansum in postharvest fruits. United States Department of Agriculture, enero de 2014. http://dx.doi.org/10.32747/2014.7600012.bard.
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Background to the topic- Penicilliumas a postharvest pathogen and producer of the mycotoxin PAT. Penicilliumspp. are destructive phytopathogens, capable of causing decay in many deciduous fruits, during postharvest handling and storage; and the resulting losses can amount to 10% of the stored produce and the accumulation of large amounts of the mycotoxinpatulin. The overall goal of this proposal is to identify critical host and pathogen factors that modulate P. expansummycotoxin genes and pathways which are required for PAT production and virulence. Our preliminary results indicated that gluconic acid are strongly affecting patulin accumulation during colonization. P. expansumacidifies apple fruit tissue during colonization in part through secretion of gluconic acid (GLA). Several publications suggested that GLA accumulation is an essential factor in P. expansumpathogenicity. Furthermore, down regulation of GOX2 significantly reduced PAT accumulation and pathogenicity. PAT is a polyketide and its biosynthesis pathway includes a 15-gene cluster. LaeA is a global regulator of mycotoxin synthesis. It is now known that patulin synthesis might be subjected to LaeA and sometimes by environmental sensing global regulatory factors including the carbon catabolite repressor CreA as well as the pH regulator factor PacC and nitrogen regulator AreA. The mechanisms by which LaeA regulates patulin synthesis was not fully known and was part of our work. Furthermore, the regulatory system that controls gene expression in accordance with ambient pH was also included in our work. PacC protein is in an inactive conformation and is unable to bind to the promoter sites of the target genes; however, under alkaline growth conditions activated PacC acts as both an activator of alkaline-expressed genes and a repressor of acid-expressed genes. The aims of the project- This project aims to provide new insights on the roles of LaeA and PacC and their signaling pathways that lead to GLA and PAT biosynthesis and pathogenicity on the host. Specifically, our specific aims were: i) To elucidate the mechanism of pH-controlled regulation of GLA and PAT, and their contribution to pathogenesis of P. expansum. We are interested to understanding how pH and/or GLA impact/s under PacC regulation affect PAT production and pathogenesis. ii) To characterize the role of LaeA, the global regulator of mycotoxin production, and its effect on PAT and PacC activity. iii) To identify the signaling pathways leading to GLA and PAT synthesis. Using state- of-the-art RNAseq technologies, we will interrogate the transcriptomes of laeAand pacCmutants, to identify the common signaling pathways regulating synthesis of both GLA and PAT. Major conclusions, solutions, achievements- In our first Aim our results demonstrated that ammonia secreted at the leading edge of the fungal colony induced transcript activation of the global pH modulator PacC and PAT accumulation in the presence of GLA. We assessed these parameters by: (i) direct exogenous treatment of P. expansumgrowing on solid medium; (ii) direct exogenous treatment on colonized apple tissue; (iii) growth under self-ammonia production conditions with limited carbon; and (iv) analysis of the transcriptional response to ammonia of the PAT biosynthesis cluster. Ammonia induced PAT accumulation concurrently with the transcript activation of pacCand PAT biosynthesis cluster genes, indicating the regulatory effect of ammonia on pacCtranscript expression under acidic conditions. Transcriptomic analysis of pH regulated processes showed that important genes and BARD Report - Project 4773 Page 2 of 10 functionalities of P. expansumwere controlled by environmental pH. The differential expression patterns of genes belonging to the same gene family suggest that genes were selectively activated according to their optimal environmental conditions to enable the fungus to cope with varying conditions and to make optimal use of available enzymes. Concerning the second and third Aims, we demonstrated that LaeA regulates several secondary metabolite genes, including the PAT gene cluster and concomitant PAT synthesis invitro. Virulence studies of ΔlaeAmutants of two geographically distant P. expansumisolates (Pe-21 from Israel and Pe-T01 from China) showed differential reduction in disease severity in freshly harvested fruit ranging from no reduction for Ch-Pe-T01 strains in immature fruit to 15–25% reduction for both strains in mature fruit, with the ΔlaeAstrains of Is-Pe-21 always showing a greater loss in virulence. Results suggest the importance of LaeA regulation of PAT and other secondary metabolites on pathogenicity. Our work also characterized for the first time the role of sucrose, a key nutritional factor present in apple fruit, as a negative regulator of laeAexpression and consequent PAT production in vitro. This is the first report of sugar regulation of laeAexpression, suggesting that its expression may be subject to catabolite repression by CreA. Some, but not all of the 54 secondary metabolite backbone genes in the P. expansumgenome, including the PAT polyketide backbone gene, were found to be regulated by LaeA. Together, these findings enable for the first time a straight analysis of a host factor that potentially activates laeAand subsequent PAT synthesis.
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Abbo, Shahal, Hongbin Zhang, Clarice Coyne, Amir Sherman, Dan Shtienberg y George J. Vandemark. Winter chickpea; towards a new winter pulse for the semiarid Pacific Northwest and wider adaptation in the Mediterranean basin. United States Department of Agriculture, enero de 2011. http://dx.doi.org/10.32747/2011.7597909.bard.
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Original objectives: [a] Screen an array of chickpea and wild annual Cicer germplasm for winter survival. [b] Genetic analysis of winter hardiness in domesticated x wild chickpea crosses. [c] Genetic analysis of vernalization response in domesticated x wild chickpea crosses. [d] Digital expression analysis of a core selection of breeding and germplasm lines of chickpea that differ in winter hardiness and vernalization. [e] Identification of the genes involved in the chickpea winter hardiness and vernalization and construction of gene network controlling these traits. [f] Assessing the phenotypic and genetic correlations between winter hardiness, vernalization response and Ascochyta blight response in chickpea. The complexity of the vernalization response and the inefficiency of our selection experiments (below) required quitting the work on ascochyta response in the framework of this project. Background to the subject: Since its introduction to the Palouse region of WA and Idaho, and the northern Great Plains, chickpea has been a spring rotation legume due to lack of winter hardiness. The short growing season of spring chickpea limits its grain yield and leaves relatively little stubble residue for combating soil erosion. In Israel, chilling temperatures limit pod setting in early springs and narrow the effective reproductive time window of the crop. Winter hardiness and vernalization response of chickpea alleles were lost due to a series of evolutionary bottlenecks; however, such alleles are prevalent in its wild progenitor’s genepool. Major conclusions, solutions, achievements: It appears that both vernalization response and winter hardiness are polygenic traits in the wild-domesticated chickpea genepool. The main conclusion from the fieldwork in Israel is that selection of domesticated winter hardy and vernalization responsive types should be conducted in late flowering and late maturity backgrounds to minimize interference by daylength and temperature response alleles (see our Plant Breeding paper on the subject). The main conclusion from the US winter-hardiness studies is that excellent lines have been identified for germplasm release and continued genetic study. Several of the lines have good seed size and growth habit that will be useful for introgressing winter-hardiness into current chickpea cultivars to develop releases for autumn sowing. We sequenced the transcriptomes and profiled the expression of genes in 87 samples. Differential expression analysis identified a total of 2,452 differentially expressed genes (DEGs) between vernalized plants and control plants, of which 287 were shared between two or more Cicer species studied. We cloned 498 genes controlling vernalization, named CVRN genes. Each of the CVRN genes contributes to flowering date advance (FDA) by 3.85% - 10.71%, but 413 (83%) other genes had negative effects on FDA, while only 83 (17%) had positive effects on FDA, when the plant is exposed to cold temperature. The cloned CVRN genes provide new toolkits and knowledge to develop chickpea cultivars that are suitable for autumn-sowing. Scientific & agricultural implications: Unlike the winter cereals (barley, wheat) or pea, in which a single allelic change may induce a switch from winter to spring habit, we were unable to find any evidence for such major gene action in chickpea. In agricultural terms this means that an alternative strategy must be employed in order to isolate late flowering – ascochyta resistant (winter types) domesticated forms to enable autumn sowing of chickpea in the US Great Plains. An environment was identified in U.S. (eastern Washington) where autumn-sown chickpea production is possible using the levels of winter-hardiness discovered once backcrossed into advanced cultivated material with acceptable agronomic traits. The cloned CVRN genes and identified gene networks significantly advance our understanding of molecular mechanisms underlying plant vernalization in general, and chickpea in particular, and provide a new toolkit for switching chickpea from a spring-sowing to autumn-sowing crop.
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Morin, Shai, Gregory Walker, Linda Walling y Asaph Aharoni. Identifying Arabidopsis thaliana Defense Genes to Phloem-feeding Insects. United States Department of Agriculture, febrero de 2013. http://dx.doi.org/10.32747/2013.7699836.bard.
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The whitefly (Bemisia tabaci) is a serious agricultural pest that afflicts a wide variety of ornamental and vegetable crop species. To enable survival on a great diversity of host plants, whiteflies must have the ability to avoid or detoxify numerous different plant defensive chemicals. Such toxins include a group of insect-deterrent molecules called glucosinolates (GSs), which also provide the pungent taste of Brassica vegetables such as radish and cabbage. In our BARD grant, we used the whitefly B. tabaci and Arabidopsis (a Brassica plant model) defense mutants and transgenic lines, to gain comprehensive understanding both on plant defense pathways against whiteflies and whitefly defense strategies against plants. Our major focus was on GSs. We produced transgenic Arabidopsis plants accumulating high levels of GSs. At the first step, we examined how exposure to high levels of GSs affects decision making and performance of whiteflies when provided plants with normal levels or high levels of GSs. Our major conclusions can be divided into three: (I) exposure to plants accumulating high levels of GSs, negatively affected the performance of both whitefly adult females and immature; (II) whitefly adult females are likely to be capable of sensing different levels of GSs in their host plants and are able to choose, for oviposition, the host plant on which their offspring survive and develop better (preference-performance relationship); (III) the dual presence of plants with normal levels and high levels of GSs, confused whitefly adult females, and led to difficulties in making a choice between the different host plants. These findings have an applicative perspective. Whiteflies are known as a serious pest of Brassica cropping systems. If the differences found here on adjacent small plants translate to field situations, intercropping with closely-related Brassica cultivars could negatively influence whitefly population build-up. At the second step, we characterized the defensive mechanisms whiteflies use to detoxify GSs and other plant toxins. We identified five detoxification genes, which can be considered as putative "key" general induced detoxifiers because their expression-levels responded to several unrelated plant toxic compounds. This knowledge is currently used (using new funding) to develop a new technology that will allow the production of pestresistant crops capable of protecting themselves from whiteflies by silencing insect detoxification genes without which successful host utilization can not occur. Finally, we made an effort to identify defense genes that deter whitefly performance, by infesting with whiteflies, wild-type and defense mutated Arabidopsis plants. The infested plants were used to construct deep-sequencing expression libraries. The 30- 50 million sequence reads per library, provide an unbiased and quantitative assessment of gene expression and contain sequences from both Arabidopsis and whiteflies. Therefore, the libraries give us sequence data that can be mined for both the plant and insect gene expression responses. An intensive analysis of these datasets is underway. We also conducted electrical penetration graph (EPG) recordings of whiteflies feeding on Arabidopsis wild-type and defense mutant plants in order to determine the time-point and feeding behavior in which plant-defense genes are expressed. We are in the process of analyzing the recordings and calculating 125 feeding behavior parameters for each whitefly. From the analyses conducted so far we conclude that the Arabidopsis defense mutants do not affect adult feeding behavior in the same manner that they affect immatures development. Analysis of the immatures feeding behavior is not yet completed, but if it shows the same disconnect between feeding behavior data and developmental rate data, we would conclude that the differences in the defense mutants are due to a qualitative effect based on the chemical constituency of the phloem sap.