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1
Newton, Craig Hunter. "A Drosophila tRNA gene family". Thesis, University of British Columbia, 1989. http://hdl.handle.net/2429/29252.
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This thesis describes a tRNA[sup Arg] gene family in the fruit fly D. melanogaster. The study was initiated in order to better understand the gene organization of a subset of this family. Of a total of 10 tRNA[sup Arg] gene copies that comprise this family, four genes are arranged tandemly on repeated sequences 200 bp and 600 bp in length. This organization suggests these four genes have undergone recent gene duplication. To investigate the significance of such events, these tRNA[sup Arg] genes were compared to other members of this gene family in regards their structure, in vitro function, and organization between different D. melanogaster strains and sibling species.
The results show that the four repeated genes differ in sequence at a single nucleotide (CI3) relative to six additional gene copies. Five of these additional genes are identical in sequence and one differs at two nucleotides (A16, A37). The gene family is organized at four different chromosomal sites. Six of the 10 gene copies occur at polytene region 12E1-2 on the X chromosome. These include the four repeated genes (R12.1-R12.4) and two additional gene copies (R12.5-R12.6). A single gene occurs at another X-linked locus located at 19F (R19.1). The three remaining gene copies occur on chromosome 3R as a gene doublet at 85C (R85.1-R85.2) and as a single gene at 83AB (R83.1).
All 10 genes in this family are active as templates for in vitro transcription in. homologous Drosophila extracts. The predicted 5' initiation sites are all very similar and occur at conserved nucleotides 4-5 bp upstream from the mature 5' ends of the genes. Six of the ten gene copies are transcribed efficiently in vitro. The four repeated gene copies however, have novel transcription properties; they are much less efficient templates in Drosophila extracts (2-5 fold) and are inhibited at KCl concentrations where other gene copies transcribe optimally. These properties do not result from the single nucleotide difference in coding sequence or an inability to form stable pre-initiation complexes. Instead they appear to result from the upstream 5' flanking sequence. These novel transcription properties are not observed in heterologous transcription systems containing human cell extracts. Instead they are transcribed efficiently relative to other members of the gene family and no longer exhibit sensitivity to KCl.
Comparison of the repeated tRNA[sup Arg] gene locus between several D. melanogaster strains indicates that this is the predominant form in the majority of wild and laboratory stocks. However, a fraction of populations (5/45) contain a variant locus that consists of only three gene copies. These have apparently lost, or not gained, one of the repeats found in the majority of populations. Similar comparisons between D. melanogaster sibling species (D. simualns, D. teissieri, D. erecta, and D. yakuba) show that only the D. melanogaster lines contain the repeated genes. Thus in the time since the divergence from its closest related sibling species (D. simulans ), D . melanogaster lines have acquired three new gene copies by duplication of a putative ancestral single gene. Analysis of the four, three, and single gene loci isolated from D. melanogaster (pDt27R, p27ry2) and D. simulans (p27simC), respectively, at the nucleotide level suggests a model to account for the evolution of this gene cluster.
One additional sequence associated with this gene family consists of a half tRNA[sup Arg] gene composed of the 3' 37 bp. This half gene contains a 3' CCA sequence and is flanked on one side by a region that is > 90% homologous to the LTR of the Drosophila retrotransposon mdg 1. It is not clear if this half gene is itself part of a related retrotransposon or has originated by recombination or aberrant reverse transcription with mdg 1. The 3' ends tRNA[sup Arg] have been proposed to function as primers for at least two classes of retrotransposon, mdg 1 and 412 (Yuki et al., 1986).Medicine, Faculty of
Biochemistry and Molecular Biology, Department of
Graduate
2
Cadieux, Benoît. "The zebrafish progranulin gene family /". Thesis, McGill University, 2003. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=84486.
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Granulins are small cysteine-rich peptide growth factors that, in mammals, are derived from a common glycoprotein precursor (progranulin) containing one half and seven non-identical tandemly repeated granulin domains. While there is evidence for only one progranulin gene in mammalian genomes, work presented in this thesis demonstrates that granulins form an extended gene family in teleost fish. Two zebrafish genes that constitute likely co-orthologues to mammalian progranulin, progranulin-a and progranulin-b, encode precursors that encode 10 and 9 copies of the granulin motif, respectively. Two additional genes in zebrafish, designated progranulin-1 and progranulin-2, each give rise to precursors consisting of one and one-half granulin-like repeats only. The progranulin-1 and progranulin-2 genes are organized in tandem, and possess exonic complementarity to a single non-coding RNA gene transcribed in the antisense orientation from the complementary DNA strand. A cDNA encoding a chimeric precursor consisting of the amino-terminal progranulin-1 followed by the carboxyl-terminal region of progranulin-2 was characterized and is likely generated through the mechanism of splicing in trans between the two primary transcripts for progranulin-1 and progranulin-2. Chromosomal assignment of the zebrafish progranulin genes indicates that progranulin-a, but not progranulin-b, is located on a chromosome that displays syntenic correspondence to mammalian progranulin. Cumulatively, the data suggest that an ancestral progranulin gene was duplicated at the base of the vertebrate radiation to generate precursors with distinct architectures and that one was lost in the lineage leading to tetrapods after the split between sarcopterygians and actinopterygians. Like their mammalian counterpart, the expression of the zebrafish progranulins is widespread in adult tissues. During development, the maternal expression of progranulin-a and progranulin-b parallels that
3
Janousek, Vaclav, Robert Karn i Christina Laukaitis. "The role of retrotransposons in gene family expansions: insights from the mouse Abp gene family". BioMed Central, 2013. http://hdl.handle.net/10150/610385.
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BACKGROUND:Retrotransposons have been suggested to provide a substrate for non-allelic homologous recombination (NAHR) and thereby promote gene family expansion. Their precise role, however, is controversial. Here we ask whether retrotransposons contributed to the recent expansions of the Androgen-binding protein (Abp) gene families that occurred independently in the mouse and rat genomes.RESULTS:Using dot plot analysis, we found that the most recent duplication in the Abp region of the mouse genome is flanked by L1Md_T elements. Analysis of the sequence of these elements revealed breakpoints that are the relicts of the recombination that caused the duplication, confirming that the duplication arose as a result of NAHR using L1 elements as substrates. L1 and ERVII retrotransposons are considerably denser in the Abp regions than in one Mb flanking regions, while other repeat types are depleted in the Abp regions compared to flanking regions. L1 retrotransposons preferentially accumulated in the Abp gene regions after lineage separation and roughly followed the pattern of Abp gene expansion. By contrast, the proportion of shared vs. lineage-specific ERVII repeats in the Abp region resembles the rest of the genome.CONCLUSIONS:We confirmed the role of L1 repeats in Abp gene duplication with the identification of recombinant L1Md_T elements at the edges of the most recent mouse Abp gene duplication. High densities of L1 and ERVII repeats were found in the Abp gene region with abrupt transitions at the region boundaries, suggesting that their higher densities are tightly associated with Abp gene duplication. We observed that the major accumulation of L1 elements occurred after the split of the mouse and rat lineages and that there is a striking overlap between the timing of L1 accumulation and expansion of the Abp gene family in the mouse genome. Establishing a link between the accumulation of L1 elements and the expansion of the Abp gene family and identification of an NAHR-related breakpoint in the most recent duplication are the main contributions of our study.
4
Thangavelu, Madan. "The actin gene family of tobacco". Thesis, University of Cambridge, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.335212.
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Cotton, James A. "Vertebrate phylogenomics and gene family evolution". Thesis, University of Glasgow, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.274764.
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Chattaway, John Antony. "Characterising the polymorphic BG gene family". Thesis, University of Cambridge, 2014. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.707953.
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Dubb, Lindsey. "A likelihood model of gene family evolution /". Thesis, Connect to this title online; UW restricted, 2005. http://hdl.handle.net/1773/10264.
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Dörr, Daniel [Verfasser]. "Gene family-free genome comparison / Daniel Dörr". Bielefeld : Universitätsbibliothek Bielefeld, 2016. http://d-nb.info/1096457229/34.
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Rawson, Stephen J. "The Chinese hamster phosphoglycerate kinase gene family". Thesis, University of Leicester, 1986. http://hdl.handle.net/2381/35136.
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I. A phosphoglycerate kinase (PGK) deficient variant cell line, R1.1.7, derived from the Chinese hamster ovary cell line, CHO-K1, is used as a recipient in the development of a DNA-mediated transfection system designed for the study of in vivo expression of exogenous PGK gene sequences. II. Several PGK DNA sequences are detected in the Chinese hamster genome by hybridisation of genomic DNA digests with a human PGK cDNA probe. A number of these sequences are shown to be X-linked. Four of the PGK sequences observed in the blot hybridisations are isolated from a CHO-K1 DNA genomic library and analysed by probing with different regions of the PGK cDNA, heteroduplex mapping and DNA sequencing. One of these sequences is a 572 bp exon from the functional X-linked PGK gene (PGK-1) which is expressed in all somatic cells. The three remaining PGK sequences are intronless pseudogenes which were apparently derived independently, from an ancestral Chinese hamster PGK gene, within the last 50 million years. They exhibit features typical of 'processed' pseudogenes which are generated via an mRNA intermediate and integrated into breaks in the chromosomal DNA.
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Drummond, Revel Scott MacGregor. "The AtMRS2 gene family from Arabidopsis thaliana". Thesis, University of Auckland, 2004. http://hdl.handle.net/2292/15.
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Magnesium (Mg2+) is an essential mineral nutrient for plants and is the most abundant free divalent cation in plant cells. However, our knowledge of the role of this ion in the plant cell is limited, and the mechanisms of homeostasis and transport of the ion are almost completely unknown. A. Tutone (this laboratory) identified an Arabidopsis thaliana gene by the complementation of a Mg2+-uptake yeast mutant (CM66). This gene, referred to as AtMRS2-11, was expressed as cDNA from a strong yeast promoter and allowed the growth of the CM66 yeast strain on standard media. The conceptually translated AtMRS2-11 protein sequence was used in this study to identify nine additional proteins by sequence homology searches using the BLAST algorithm. The corresponding genes have been cloned from cDNA (A. thaliana ecotype Landsberg erecta) and sequenced. Protein sequence similarity suggests that the family forms a sub-section of the CorA super-family of Mg2+ transport proteins. The mutant yeast used to identify the family initially was also used to show that two family members in addition to AtMRS2-11 were able to complement the Mg2+-dependent growth phenotype. When fused to eGFP, these proteins showed a localisation consistent with some of the protein reaching the yeast cell membrane. The other members of the family were also fused to eGFP and showed a range of localisation patterns within the yeast cell. None of the three AtMRS2 proteins previously able to complement the yeast mutant phenotype did so when fused to eGFP. RNA transcripts from the AtMRS2 family were detected by RT-PCR in organ-scale preparations of total RNA from A. thaliana. Most family members were detected in all of the organs tested. Northern analysis of AtMRS2-11 RNA transcript level showed that the gene was more highly expressed in leaf tissue, but was not affected by decreased levels of Mg2+ in the growth media. The levels of steady state AtMRS2-11 mRNA transcript were elevated two-fold in the light during the diurnal cycle, but no change was detected during light-induced greening of etiolated seedlings. A stable transgenic A. thaliana line expressing the gusA gene from the promoter region of AtMRS2-11 was used to localise the promoter's activity to cells containing chloroplasts. The expression appeared highest in younger cells. VI The AtMRS2-11 protein was predicted to contain a chloroplast targeting peptide. Western analysis demonstrated that AtMRS2-11 was enriched in the total proteins of isolated chloroplasts as compared to extracts from whole plants. The AtMRS2-11:eGFP fusion protein was also detected in chloroplasts by fluorescence microscopy. Flame atomic absorption spectroscopy was used in conjunction with isolated chloroplasts to try to determine the effects of the overaccumulation of the AtMRS2-11 protein in a transgenic A. thaliana plant line (constructed by A. Tutone). A rapid uptake or binding of Mg2+ was seen in chloroplasts isolated from both wild type and transgenic lines, but no differences were observed in either the rate of Mg2+ uptake/binding or the final Mg2+ content.
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Sjöstrand, Joel. "Reconciling gene family evolution and species evolution". Doctoral thesis, Stockholms universitet, Numerisk analys och datalogi (NADA), 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-93346.
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Species evolution can often be adequately described with a phylogenetic tree. Interestingly, this is the case also for the evolution of homologous genes; a gene in an ancestral species may – through gene duplication, gene loss, lateral gene transfer (LGT), and speciation events – give rise to a gene family distributed across contemporaneous species. However, molecular sequence evolution and genetic recombination make the history – the gene tree – non-trivial to reconstruct from present-day sequences. This history is of biological interest, e.g., for inferring potential functional equivalences of extant gene pairs. In this thesis, we present biologically sound probabilistic models for gene family evolution guided by species evolution – effectively yielding a gene-species tree reconciliation. Using Bayesian Markov-chain Monte Carlo (MCMC) inference techniques, we show that by taking advantage of the information provided by the species tree, our methods achieve more reliable gene tree estimates than traditional species tree-uninformed approaches. Specifically, we describe a comprehensive model that accounts for gene duplication, gene loss, a relaxed molecular clock, and sequence evolution, and we show that the method performs admirably on synthetic and biological data. Further-more, we present two expansions of the inference procedure, enabling it to pro-vide (i) refined gene tree estimates with timed duplications, and (ii) probabilistic orthology estimates – i.e., that the origin of a pair of extant genes is a speciation. Finally, we present a substantial development of the model to account also for LGT. A sophisticated algorithmic framework of dynamic programming and numerical methods for differential equations is used to resolve the computational hurdles that LGT brings about. We apply the method on two bacterial datasets where LGT is believed to be prominent, in order to estimate genome-wide LGT and duplication rates. We further show that traditional methods – in which gene trees are reconstructed and reconciled with the species tree in separate stages – are prone to yield inferior gene tree estimates that will overestimate the number of LGT events.Arters evolution kan i många fall beskrivas med ett träd, vilket redan Darwins anteckningsböcker från HMS Beagle vittnar om. Detta gäller också homologa gener; en gen i en ancestral art kan – genom genduplikationer, genförluster, lateral gentransfer (LGT) och artbildningar – ge upphov till en genfamilj spridd över samtida arter. Att från sekvenser från nu levande arter rekonstruera genfamiljens framväxt – genträdet – är icke-trivialt på grund av genetisk rekombination och sekvensevolution. Genträdet är emellertid av biologiskt intresse, i synnerhet för att det möjliggör antaganden om funktionellt släktskap mellan nutida genpar. Denna avhandling behandlar biologiskt välgrundade sannolikhetsmodeller för genfamiljsevolution. Dessa modeller tar hjälp av artevolutionens starka inverkan på genfamiljens historia, och ger väsentligen upphov till en förlikning av genträd och artträd. Genom Bayesiansk inferens baserad på Markov-chain Monte Carlo (MCMC) visar vi att våra metoder presterar bättre genträdsskattningar än traditionella ansatser som inte tar artträdet i beaktning. Mer specifikt beskriver vi en modell som omfattar genduplikationer, genförluster, en relaxerad molekylär klocka, samt sekvensevolution, och visar att metoden ger högkvalitativa skattningar på både syntetiska och biologiska data. Vidare presenterar vi två utvidgningar av detta ramverk som möjliggör (i) genträdsskattningar med tidpunkter för duplikationer, samt (ii) probabilistiska ortologiskattningar – d.v.s. att två nutida gener härstammar från en artbildning. Slutligen presenterar vi en modell som inkluderar LGT utöver ovan nämnda mekanismer. De beräkningsmässiga svårigheter som LGT ger upphov till löses med ett intrikat ramverk av dynamisk programmering och numeriska metoder för differentialekvationer. Vi tillämpar metoden för att skatta LGT- och duplikationsraten hos två bakteriella dataset där LGT förmodas ha spelat en central roll. Vi visar också att traditionella metoder – där genträd skattas och förlikas med artträdet i separata steg – tenderar att ge sämre genträdsskattningar, och därmed överskatta antalet LGT-händelser.
At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 3: Manuscript. Paper 5: Manuscript.
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Buerger, Katrin. "Functional analysis of the Mospd gene family". Thesis, University of Edinburgh, 2010. http://hdl.handle.net/1842/4435.
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Mospd3, a gene located on mouse chromosome 5, was identified in a gene trap screen in ES cells. The gene trap vector integration in multiple copies into the putative promoter of the gene, resulted in a loss of expression of Mospd3 at the trapped allele. In mice generated from ES cells carrying the vector integration it was found that the lack of Mospd3 expression resulted in the death of a proportion of the homozygote mutants within the first day after birth. Homozygote neonates exhibited a thinning of the right ventricular free heart wall which resembles other mouse mutant phenotypes as well as human congenital heart defects caused by a loss of desmosome and adherens junction mediated cell adhesion between cardiomyocytes. The protein encoded by Mospd3, contains an N-terminal Major Sperm Protein (MSP) domain implicated as a mediator of protein- protein interactions, as well as a two C-terminal transmembrane domains. Both, protein structure and phenotypic similarities with defects in desmosomal and adherens junction proteins suggests that Mospd proteins might play a role in cell adhesion and maintaining the structural integrity of the heart. The phenotype of Mospd3 mutants was highly dependent on genetic background, which led us to speculate that there might be genetic redundancy between Mospd3 and its closest family member the X-linked Mospd1. The aims of this thesis were to generate tools to better understand the function of the Mospd gene family in cardiac development as well as assessing genetic redundancy between Mospd1 and Mospd3. A conditional gene targeting strategy was designed for both Mospd genes. Large genomic regions of the Mospd1 and Mospd3 loci were subcloned from bacterial artificial chromosomes (BACs) and using a recombineering approach, loxP sites and a drug selection cassette (neomycin) were placed in precise locations surrounding the MSP domain of both genes. The conditional targeting vectors were electroporated into both CGR8 and E14 ES cells and homologous recombinant clones were identified at a frequency of 2% and 1.3% for Mospd1 and Mospd3 respectively. Five euploid targeted clones for both Mospd1 and Mospd3 have been generated. Transient expression of Cre recombinase in ES cells carrying the conditional Mospd1 allele was used to delete the one copy of this X-linked gene. Phenotypic characterisation of this null ES cell line revealed that Mospd1 is neither essential for ES cell viability and self-renewal, nor for the early differentiation of these cells towards a cardiac fate. In order to investigate the mechanism of action of Mospd proteins, specific polyclonal antibodies were generated to detect either Mospd1 or Mospd3. These antibodies were purified and tested by western blotting using COS7 cells overexpressing either Mospd protein as well as mouse tissue lysates. Whilst the antibodies were found to detect the proteins and differentiate between Mospd1 and Mospd3, they showed insufficient purification to be used in co-localisation and co-immunoprecipitation experiments to identify interacting proteins and determine whether Mospd proteins are involved in cell adhesion complexes. Monoclonal antibodies were subsequently generated and initial western blotting experiments showed promising results, indicating that these antibodies may be better suited for immunohistochemical analysis of Mospd proteins.
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Tregear, James W. "The lectin gene family of Ricinus communis". Thesis, University of Warwick, 1989. http://wrap.warwick.ac.uk/101217/.
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The aim of this project has been to isolate, characterise and investigate the expression patterns of the various members of the castor bean lectin gene family. Genomic Southern blotting experiments showed that the gene family contains approximately eight members, of which two appear to be ricin-like. Castor bean genomic DNA was cloned into a bacteriophage lambda vector and the resulting recombinant clones screened with a ricin cDNA probe. Seventeen positive clones were isolated, amongst which at least five different groups could be recognised, on the basis of Southern blotting data. Four different lambda clones were selected for further analysis. One of the clones was found to contain a functional ricin gene with an identical restriction pattern to that of the ricin cDNA, but none of the clones appears to contain an authentic Riclnus communis agglutinin (RCA I) gene. DNA sequencing and RNAse protection data showed that three of the clones analysed contain lectin pseudogenes. The expression pattern of the functional ricin gene in pCBG3Hl (lambda clone 10) was investigated at the transcriptional level using RNAse protection. The results obtained show that the mRNA transcribed from this gene accumulates during the late (post-testa) stages of seed development. The pCBG3Hl ricin gene appears to use multiple cap and poly(A) sites. The developmental profile of lectin gene transcript levels observed in this study is similar to the patterns previously observed at the protein and translatable mRNA levels. This indicates a close correlation between the accumulation of the lectin proteins and the amounts of steady state transcripts. DNA sequencing enabled the identification of putative transcriptional regulatory elements in the promoter of the pCBG3Hl ricin gene, including an element resembling the RY repeat previously implicated in seed-specific gene expression. Ultimately, it is hoped that studies of this type will make it possible for the network of regulatory processes governing the expression pattern of the castor bean lectin genes to be unravelled.
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Tunnacliffe, Edward Alan John. "Gene expression dynamics underlying diversification and expansion of an actin gene family". Thesis, University College London (University of London), 2018. http://discovery.ucl.ac.uk/10041510/.
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During the evolution of gene families, functional diversification of proteins often follows gene duplication. However, some gene families expand while preserving protein sequence. Why would a cell need to maintain multiple copies of the same gene? In this thesis I have addressed this question for an actin gene family containing 17 genes encoding an identical protein in the social amoeba Dictyostelium discoideum. Using bioinformatics I identified several highly conserved sequence elements as potential regulatory motifs, yet found that gene expression patterns during development are broadly similar across the gene family. Turning to live cell imaging I showed that family members display different transcription dynamics, with strong 'bursty' behaviours contrasted by more steady, continuous transcriptional activity. By switching promoters I showed that different dynamics are directly determined by endogenous promoter sequences, rather than genomic context. I have explored how cell-to-cell variability in gene expression introduced by bursty transcription propagates to resultant cytoplasmic mRNA and protein and showed that population variance of these molecules is reduced compared to nascent transcription. Finally, I generated cell lines with up to 6 genes knocked out and showed that these cells potentially display a minor defect in growth. Overall these data suggest that expanded gene families are utilised not only to generate sufficient protein for normal cell physiology, but also to enable both robustness and responsiveness to a range of stimuli regulating the expression of essential genes.
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Jopling, Catherine L. "Internal ribosome entry in the myc gene family". Thesis, University of Leicester, 2001. http://hdl.handle.net/2381/29662.
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The proto-oncogene c-myc is encoded by a transcript in which the 5' UTR contains a potent internal ribosome entry segment (IRES). The N-myc gene shows considerable homology to c-myc and also possesses a 5' UTR that is long and structured. Thus, the potential for internal ribosome entry within this UTR was examined. N-myc was found to contain an IRES that was of comparable activity to that of c-myc in non-neuronal cells, but was specifically activated relative to the c-myc IRES in neuronal cells in which the N-myc transcription is expressed. Furthermore, the activity of the N-myc IRES was specifically inhibited during neuronal differentiation, when N-myc expression is reduced. The trans-acting factor requirements for N-myc IRES function were examined and a candidate protein was found, although not characterised. An IRES was also identified in the 5' UTR of the third well-studied member of the myc gene family, L-myc. An alternative form of the UTR exists in which an intron is retained, but it was not possible to draw any definite conclusions on the IRES activity of this UTR. Translation of both c- and N-myc mRNAs can occur by both cap-dependent and IRES-dependent mechanisms, so the existence of IRESs within these transcripts was intriguing. c-Myc protein levels were analysed during apoptosis and were maintained, despite the apoptotic inhibition of protein synthesis and the short half-life of c-Myc. The activity of the c-myc IRES was maintained during apoptosis and was responsible for this effect. The c-myc IRES was also shown to lie downstream of the p38 mitogen-activated protein kinase signalling pathway.
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David, Jocelyn. "Characterization of the nlp gene family of Enterobacteriaceae". Thesis, McGill University, 1994. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=68166.
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Bacterial species have been classified according to physiological, biochemical and immunological features. The sequencing of homologous genes present in various species can provide new insights for bacterial taxonomy and for the comprehension of molecular mechanisms involved in evolution.Recently, a new gene, called nlp (for Ner-like-protein), was discovered in E. coli and was shown to also be present in several other Enterobacteriaceae. The Nlp protein is highly homologous to the Ner repressors of transposable bacteriophages Mu and D108.
In order to determine if the nucleotide sequence of the nlp gene was conserved in enteric bacteria, and also for studying the potential evolutionary relationship between bacteria and bacteriophages, the E. coli C nlp gene was cloned and sequenced. The resulting nucleotide sequence was compared to the nlp genes of E. coli W3110 and Shigella sonneii.
Results showed that the coding region of the E. coli C nlp gene is identical to its E. coli W3110 counterpart. In S. sonneii, the nlp gene sequence revealed three nucleotide substitutions when compared to the two E. coli nlp sequences. Nevertheless, these variations were located in the third position of codons and had no effect on the primary structure of the Nlp protein.
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Durcan, Peter Joseph. "Examination of the Kirrel gene family during myogenesis". Thesis, Manchester Metropolitan University, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.556700.
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Somatic cell fusion is essential for the in vivo function of skeletal muscle, osteoclasts and trophoblasts. A diverse range of additional tissues including brain, heart, liver, prostate and intestinal epithelium are also subject to somatic cell fusion events in vivo. Fusion of embryonic stem cells has been reported and it has been hypothesised that fusion of cancer cells with macrophages may enable metastases. Furthermore, somatic cell fusion of Dystrophin positive cells with Dystrophin negative muscle cells may be therapeutically beneficial for the treatment of muscular dystrophy. In Drosophila, the type 1 transmembrane proteins Kin of Irre (Kirre), Roughest (Rst), Hibris and Sticks and Stones (SnS) are involved in regulating the muscle cell fusion process during larval development. The mammalian orthologues of Kirre and Rst include: Kirrel, Kirrel2 and Kirrel3 while Nephrin is the mammalian orthologue to Hibris and SnS. It is currently unclear whether the Kirrel family and Nephrin are expressed in mammalian skeletal muscle cells and whether they regulate the cell fusion process in these cells, as is the case in Drosophila. It was therefore hypothesised that all Kirrel family members and Nephrin would be temporally expressed in mammalian skeletal muscle cells as they undergo cell fusion events and hence may regulate the somatic cell fusion process. It was further hypothesised that inhibition of fusion would alter their expression patterns. Presented within this thesis are novel findings regarding the detection and expression profiling of all Kirrel family members and Nephrin during in vitro myogenesis of the C2C12 murine skeletal muscle cell line. Previously unreported splice variants of Kirrel and Kirrel3 have also been identified in C2C12 cells and in additional murine tissues. Variable expression patterns among family members are reported. The presence of multiple Kirrel family members and Nephrin in C2C12 cells suggest that redundancy and/or compensatory mechanisms are in place, as is the case in Drosophila, with regards mammalian muscle cell fusion in vivo. Results presented within this thesis lay the foundations for improving understanding of the molecular mechanisms underpinning mammalian somatic cell fusion events during development, injury repair and hypertrophy and also may enable increased efficacy of cellular therapies for diseases such as muscular dystrophy and the prevention of cancer metastasis.
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Kuo, Chien-Wen Sharon. "The genomic structure of the CYP4 gene family". Thesis, University of Nottingham, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.310930.
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Gay, Robert Daniel. "Neuronal gene regulation by POU family transcription factors". Thesis, University College London (University of London), 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.267026.
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Singh, Prashant. "Molecular analysis of the Arabidopsis CP12 gene family". Thesis, University of Essex, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.437812.
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Bilsland, Caroline A. G. "Expression of the human leucocyte CD1 gene family". Thesis, University of Cambridge, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.334101.
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Nichols, Hester. "An analysis of human cytomegalovirus gene family function". Thesis, Cardiff University, 2018. http://orca.cf.ac.uk/115570/.
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Human cytomegalovirus (HCMV) is a β-herpesvirus that causes complications in immuno-compromised individuals and is the leading infectious cause of birth defects. The HCMV genome contains 15 gene families, which contain between 2 to 14 members. One of these, the US12 gene family, consists of a sequential cluster of 10 genes (US12 to US21) that are highly conserved in clinical isolates. This family has roles in tropism and immune evasion and was recently found to regulate the cell surface expression of a wide array of immune ligands. This included the regulation of ligands for the natural killer (NK) cell activating receptors NKG2D and NKp30 (MICA and B7-H6 respectively), which were targeted by US18 and US20. To complement these mechanistic studies, a C-terminal V5 epitope tag was added to each US12 family gene within the HCMV Merlin genome. A large proportion of the US12 family were shown to be degraded within the cell, possibly within lysosomes, which suggests that they may interact with their targets proteins in order to redirect them for degradation. Expression of US12 family members was detectable by immunoblotting during an infection time-course, with many US12 family members expressed during the Tp3 temporal class of HCMV gene expression. Three members of the family were also demonstrated to be N-glycosylated during HCMV infection. The US12 family appear to have associations with the virion assembly compartment, and correspondingly, 7 US12 family members are found within the virion. Furthermore, the majority of the US12 family also show co-localisation with endoplasmic reticulum-derived membranes. These data build on our previous functional characterisation to give insights into the workings of this important HCMV gene family.
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Wise, Dawnne O'neal. "The (gamma)-tubulin gene family in Homo sapiens /". The Ohio State University, 2000. http://rave.ohiolink.edu/etdc/view?acc_num=osu1488193272069132.
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Tilley, Michael R. "Inheritance and gene regulation in a ribosomal protein gene family of arabidopsis thaliana". The Ohio State University, 2003. http://rave.ohiolink.edu/etdc/view?acc_num=osu1071849759.
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Carneiro, Newton Portilho 1963. "Patterns of gene expression in maize endosperm: Characterization of the eEF1A gene family". Diss., The University of Arizona, 1998. http://hdl.handle.net/10150/282611.
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One of the major challenges for maize improvement is to enhance the protein quality of the endosperm. We do not know what genes encode the proteins that contribute most to the protein quality, but lysine is the most limiting amino acid. One way to determine the proteins made in the endosperm is by isolating the genes expressed in this tissue and identifying their function. The results of the maize genome project with etiolated seedling and endosperm cDNA libraries support the basis of this strategy, in that the putative functions of a large number of cDNA sequences were identified through sequence similarity comparison and genomic Southern analyses. One of the genes I selected for further analyses is the elongation factor 1 alpha (eEF1A) gene family. eEF1A interacts with many cellular components and is therefore classified as a multifunction protein. In addition, its level is highly correlated with the amount of protein-bound lysine in maize endosperm. Even though many proteins are known to interact with eEF1A, the basis for the relationship between eEF1A and endosperm lysine content is not known. Transcript level and sequence of different members of the maize eEF1A gene family were analyzed in this work. All the eEF1A maize genes examined had GTP, aminoacyl tRNA, eEF1B and actin binding domains. The substitution of glutamic acid for aspartic acid in a region that has been shown to be important for actin binding in eEF1Aa, eEF1Ae and eEF1Af suggest that there might be two groups of eEF1A genes that bind differently to actin. Analysis of transcript levels demonstrated that different members of the eEF1A gene family are expressed at different levels in the tissues examined. The results from the analyses of transcript levels demonstrated that most of the maize eEF1A gene family members are expressed and their mRNAs vary in different tissues and in developing endosperm. Physiological differences were also determined for the two most abundant eEF1As members by the yeast two-hybrid system. This research provides a significant step toward understanding eEF1A functions in maize and why this protein correlates with the lysine content of the endosperm.
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Lloyd, Sarah Elisabeth. "Analysis of ZNF6 : a human zinc finger gene related to the ZFY gene family". Thesis, University of Cambridge, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.320126.
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Collignon, Jerome Vincent. "Study of a new family of genes relating to the mammalian testis determining gene". Thesis, University College London (University of London), 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.316658.
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O'Leary, Christine Marie. "Expression of the Ets family in the lens". Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file 2.78 Mb., 100 p, 2005. http://wwwlib.umi.com/dissertations/fullcit/1428194.
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Adra, Chaker Nadim. "X chromosome inactivation and the phosphoglycerate kinase gene family". Thesis, University of Ottawa (Canada), 1988. http://hdl.handle.net/10393/5308.
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Dyall, Sabrina Devi. "Characterisation of the LmcDNA2 gene family of Leishmania major". Thesis, Imperial College London, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.243853.
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Green, Jasper B. "The stomatin family and its gene neighbours throughout prokaryotes". Thesis, University of York, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.519845.
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Tomkins, Janine. "Molecular and evolutionary investigation of the phosphoglucomutase gene family". Thesis, University College London (University of London), 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.362936.
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Abuzaid, Amani Omar S. "Functional analysis of the CP12 gene family in Arabidopsis". Thesis, University of Essex, 2017. http://repository.essex.ac.uk/20292/.
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The chloroplast protein CP12 is present in almost all photosynthetic organisms. This protein has been shown to regulate the activity of two enzymes of the Calvin-Benson cycle, namely glyceraldehyde 3-phosphate dehydrogenase (GAPDH) and phosphoribulokinase (PRK). The regulation of these enzymes is achieved by the reversible formation of this multiprotein complex in response to a change in light intensity. In Arabidopsis, there are three CP12 genes, CP12-1, CP12-2 and CP12-3. Expression analysis of these genes suggested that they may have a wider role in non-photosynthetic plastids through the plants’ life cycle and that their function may not be restricted to the Calvin-Benson cycle. The main aim of this study was to determine the functional significance of having three CP12 isoforms and to explore the importance of each individual isoform in vivo. This was done by using Arabidopsis thaliana T-DNA mutant and RNAi transgenic lines with a reduced level of CP12. Our results revealed that single mutant lines did not develop a severe growth phenotype. However, a reduction in the transcript of more than one CP12 gene, in a number of multiple lines, led to a significant reduction in photosynthetic capacity at early stages of development and a severe growth phenotype, including reduced fresh and dry weight, number of leaves and seed yield, as well as affected lateral roots formation. Complementation analysis of CP12-1 in the triple mutant revealed that two out of the three lines rescued the phenotype by showing normal growth and development, confirming the importance of CP12. Our results suggest that the CP12 protein family is essential for normal growth and development and that these proteins are likely to have additional functions apart from the regulation of Calvin-Benson cycle enzymes.
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Lipinski, Marta M. (Marta Monika) 1971. "The retinoblastoma gene family in tumor suppression and development". Thesis, Massachusetts Institute of Technology, 2001. http://hdl.handle.net/1721.1/8317.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Biology, February 2002.Includes bibliographical references.
The retinoblastoma tumor suppressor and the closely related p107 and p130 proteins play important roles in the regulation of both tumorigenesis and tissue-specific differentiation. To determine the role of Rb in development more precisely, we analyzed chimeric embryos and adults made with marked Rb-/- cells. We demonstrated that although brains of chimeric embryos exhibited extensive ectopic S-phase entry, unlike in germline Rb-/- littermates, in these chimeras the majority of Rb-deficient cells survived and differentiated into neuronal fates. Therefore, the role of Rb during development can be divided into a cell-autonomous function in exit from the cell cycle and a non-cell autonomous role in the suppression of apoptosis and induction of differentiation. Rb-/- ES cells were also able to efficiently differentiate into neurons in vitro. However, similarly to the situation observed in the chimeric embryos, Rb-/- neuronal cells failed to properly exit the cell cycle and continued to progress through the S-phase, while displaying fully differentiated neuronal morphology and expressing mature neuronal markers. Therefore, Rb function is not required for the commitment to the neuronal lineage or progression of neuronal differentiation but necessary for the cell cycle exit of differentiating neurons. In agreement, in wild-type differentiating ES cells, activity of the retinoblastoma protein (pRB) was increased specifically at the time of neuronal precursor cell cycle exit.
(cont.) In differentiating Rb-/- ES cells, levels of the pRB-related p107 protein were specifically elevated, suggesting that it might be substituting for pRB to allow efficient neuronal differentiation. In order to determine if p107 and p130 proteins might play a role in tissue-specificity of tumorigenesis upon loss of Rb, we investigated the function of these proteins in the mouse pituitary tumors. Both p107 and p130 were present and active in primary pituitary tumors but levels of p107 were very low while protein levels if pocket-family targets, E2F 1 and E2F 4 were elevated. Although normally bound exclusively to E2F 4, in pituitary tumors p107 and p130 were able to form complexes also with E2F 1. Therefore, in the absence of pRB, p107 and p130 are able to bind and may regulate the function of the activating E2F species. Despite this partial substitution, p107 and p130 are unable to prevent pituitary tumorigenesis in Rb+'- mice, likely due to the elevated E2F expression. The levels of expression of the pRB- versus the E2F-family proteins in different tissues might be contributing to the sensitivity of these tissues to tumor development upon loss of Rb.
Marta M. Lipinski.
Ph.D.
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Aguileta, Estrada Elizabeth Gabriela. "The evolution of the vertebrate beta globin gene family". Thesis, University College London (University of London), 2004. http://discovery.ucl.ac.uk/1446501/.
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This thesis covers different aspects of the evolution of the vertebrate beta globin gene family. A wealth of data on globins has been accumulated over decades of work in diverse areas, this information, together with the use of new methods, allowed a comprehensive analysis of beta globins. First, a review on the current knowledge of gene family evolution is made and the general objectives of the thesis are stated. This introductory chapter is followed by the careful analysis of the beta globin phylogeny comparing different reconstruction methods and discussing the differences between species and gene tree topologies. The molecular evolution of this gene family is investigated using codon models of sequence evolution. Particular emphasis is put on the role of gene conversion and positive selection acting at sites in the genes and along branches in the phylogeny. Also, several models of evolution by gene duplication are tested and results are analysed in the light of the different hypotheses on gene family evolution. The third chapter is devoted to the evolution of the globin protein structure from the analysis of sequence data. The ancestral state reconstruction of structurally relevant amino acids in different globins is conducted and the substitution pathway leading to the observed data is examined. The impact of amino acid changes in the hemoglobin protein is evaluated in terms of structural and functional constraints and the role of positive selection on the protein products of these genes is explored. Also, a possible case of coevolution between residues in the alpha and beta subunits of hemoglobin is proposed. Finally, using new and more sophisticated methods, I estimate dates for gene duplication and gene divergence events in the beta globin family. Two different methods of date estimation based on molecular data are compared and evolutionary rate variation in this gene family is tested.
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Wyatt, Niki Danielle. "Role of the STRA6 gene family in vertebrate development". Thesis, University of Edinburgh, 2013. http://hdl.handle.net/1842/11715.
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Matthew-Wood syndrome is a rare human birth defect condition defined by the phenotypic constellation of clinical anophthalmia, diaphragmatic hernia, pulmonary hypoplasia and cardiac defects. Matthew-Wood syndrome has a high mortality rate, with most patients dying due to respiratory insufficiency as a consequence of pulmonary hypoplasia, within the first year of life. Mutations within STRA6 are causative for Matthew-Wood syndrome. STRA6 acts as a retinol transporter for retinol bound to its physiological carrier RBP4 allowing regulated entry of retinol into the cell. A mammalian model for Matthew-Wood syndrome was not found within the literature; however a morpholino knockdown of stra6 in the zebrafish did show phenotypic features consistent with those observed in human patients. The desire to create a mammalian model of Matthew-Wood syndrome drove the work contained within this thesis. Stra6-/- mice do not represent a model for Matthew-Wood syndrome with homozygous animals being viable, found in the expected ratio and demonstrating none of the developmental abnormalities observed in human patients. Retinal defects, cataracts and persistent hyperplastic primary vitereous affect the microphthalmic eye of Stra6-/- offspring of Stra6-/- mothers fed a retinoid-free diet from plug to birth indicating that Stra6 is required for normal eye development under low-retinoid stress. The disparity in phenotype between human Matthew-Wood patients and Stra6-/- mice may be the result of functional redundancy in the mouse between Stra6 and its paralogue, Stra6.2. Stra6.2 is well conserved through evolution and is found in diverse species, including the basal eumetazoan Trichoplax. STRA6.2 has become split across its resident chromosome with an associated break in gene synteny, in humans and great apes, causing most of the gene to no longer be transcribed. However a small portion of the gene, representing the final transmembrane domain and the C-terminal intracellular tail of the protein, remains expressed in human. stra6.2 is required for normal development in the zebrafish with stra6.2 morphants being phenotypically distinguishable from control injected embryos from the 10-somite stage by a larger head-tail distance indicating an axial extension defect. stra6.2 morphants also display microphthalmia, jaw malformation, shortened and curved body axis and retinal lamination defects. stra6.2 was found to be required to prevent an excess of retinoic acid resulting in an upregulation of retinoic acid-dependent gene expression through an increase in RA synthesis by Raldh enzymes in morphants. Stra6.2-/- mice are viable and fertile and phenotypically normal, even under retinoid-stress, supporting the notion of functional redundancy. In compound knockouts, normal development and postnatal survival can be maintained by a single copy of Stra6 in Stra6+/-;Stra6.2-/- animals. Stra6.2 is less able to support normal development and survival with ~50% of Stra6-/-;Stra6.2+/- animals dying before weaning or showing reduced growth although the remaining animals are indistinguishable from their littermates. Stra6 and Stra6.2 are functionally redundant for development under normal dietary conditions in the mouse and a single copy of either is able to support development in at least 50% of animals. Stra6-/-;Stra6.2-/- mice were therefore hypothesised to be the logical mouse model of Matthew-Wood syndrome, however these mice die early in gestation between E7.5-E9.5. The early embryonic lethality in Stra6-/-;Stra6.2-/- mouse embryos compared to postnatal survival in human Matthew-Wood patients, to which they are the comparable genetic model, could be attributed to the shortened STRA6.2 remaining within the human genome. The equivalent portion of Stra6 has validated signalling motifs, which may still be active in STRA6.2, allowing development to proceed in human ‘STRA6-/-’ embryos.
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Inada, Akari. "The regulation of insulin gene transcription by CREM family". Kyoto University, 2001. http://hdl.handle.net/2433/150503.
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Elferink, Lisa Anne. "Characterization of the chicken phenobarbital inducible P450 gene family /". Title page, contents and introduction only, 1987. http://web4.library.adelaide.edu.au/theses/09PH/09phe39.pdf.
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Kingo, Külli. "The interleuken-10 family cytokines gene polymorphisms in plaque psoriasis /". Online version, 2005. http://dspace.utlib.ee/dspace/bitstream/10062/1281/5/kingo.pdf.
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Eades, Caleb Joshua. "Characterization of the alpha-mannosidase gene family in filamentous fungi". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/NQ58565.pdf.
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Cochrane, Fiona Gutiez. "Characterisation of the SIRP gene family and CD47 viral homologues". Thesis, University of Oxford, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.419242.
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Kim, Jeehee. "Biological role and genetic redundancy within the ebf gene family". Diss., Ludwig-Maximilians-Universität München, 2015. http://nbn-resolving.de/urn:nbn:de:bvb:19-182813.
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Edwards, Eira Wyn. "Molecular biology of the oleosin gene family of Brassica napus". Thesis, Durham University, 1991. http://etheses.dur.ac.uk/6160/.
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Oilseed rape (Brassica napus) is a valuable oil producing crop plant. Oil is produced by developing seeds and constitutes 45% of the dry seed weight. Storage oil is deposited as triacylglycerol in spherical structures called oil bodies. These are coated by a phospholipid monolayer interspersed with proteins called oleosins, which serve as emulsifiers, retaining the integrity of individual oil bodies. In this project the oleosin gene family of B. napus was studied. Sequence information was obtained on two oleosin cDNA clones and a genomic clone was also isolated. The sequences for oleosins from B. napus were compared with those isolated from other plant species. Preliminary expression studies were carried out, relating the timing of oleosin mRNA and protein production to the stages of embryo development. These results give an indication of the importance of transcriptional and post-transcriptional processes in the control of oleosin expression.
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Lucas, Carolina Escobar. "Regulation of the ascorbate peroxidase gene family in Arabidopsis thaliana". Thesis, University of East Anglia, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.267771.
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Virk, Guneet Kaur. "Characterization of the CPI-17 Gene Family in Danio rerio". Scholarly Commons, 2016. https://scholarlycommons.pacific.edu/uop_etds/3141.
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Regulation of smooth muscle contraction depends on the phosphorylated state of myosin light chain (MLC). Although there are many kinases responsible for phosphorylating MLC, the myosin phosphatase complex is solely accountable for its dephosphorylation. Myosin phosphatase, in turn, is tightly regulated by many proteins. One of them being the CPI-17 gene family, which inhibits myosin phosphatase. This family of proteins is composed of CPI-17 itself, PHI-1, KEPI, and GBPI. Zebrafish have two genes each of CPI-17 and PHI-1, which are expressed during early embryonic development. This study sets out to investigate whether the two isoforms of CPI-17 and PHI-1 have diverged in function or expression using zebrafish as a model organism. Through a series of biochemical tests and assays, we have determined that the two isoforms have diverged in their expression pattern from each other, however they have similar function.
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Stock, C. J. W. "The interleukin 1 gene family in systemic juvenile idiopathic arthritis". Thesis, University College London (University of London), 2011. http://discovery.ucl.ac.uk/1331908/.
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Patients with systemic Juvenile Idiopathic Arthritis (sJIA) have elevated serum levels of inflammatory cytokines. Treatment with interleukin-1 (IL-1) receptor antagonist (Anakinra) shows remarkable improvement in some sJIA patients. The hypothesis of this thesis is that genetic variations in IL-1 family genes contribute to disease pathogenesis. To investigate this, a two-stage case-control association study of 20 candidate genes was performed. Selected tagging SNPs were tested for association in 130 sJIA patients and 146 controls in stage-1 of the study. SNPs at significantly different frequencies in the cohorts were genotyped in an additional 105 sJIA patients and 184 controls, and stratified metaanalysis of the two-stage data performed. Analysis was also performed with 4,671 controls from the Wellcome Trust Case Control Consortium (WTCCC). No associations were found with caspase-1, cryopyrin, or IL-18. Significant disease associations were identified with SNPs in the ligand IL1A, the receptor antagonist IL1RN, and a two-SNP haplotype in the IL-18 antagonist IL18BP. Associations were also identified in the decoy receptor IL1R2, and the co-receptor IL1RAP, although these were not confirmed when re-analysed with the WTCCC controls. Transient transfection assays with haplotype constructs, performed by Dr Wen, showed that the IL18BP haplotype affected gene transcription levels in vitro. This effect was not however reproduced using PBMCs from healthy individuals. Allele specific binding to one of the haplotype SNPs was predicted in silico, but no evidence for this was seen in EMSA experiments. Further functional studies are required to corroborate involvement of this haplotype in disease. In summary, this study has identified genetic associations for susceptibility to sJIA with a number of IL1 family members. These results indicate that there may be aberrant control of IL-1 activity in patients with sJIA. Further work is required to determine how these associated SNPs affect IL-1 activity, and thereby the inflammatory response in sJIA.
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Lawton, J. C. "Investigation of the cir multi-gene family of Plasmodium chabaudi". Thesis, University College London (University of London), 2012. http://discovery.ucl.ac.uk/1338585/.
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The pir genes comprise the largest multi-gene family in Plasmodium, with members found in P. vivax, P. knowlesi and rodent malaria species. Despite their almost universal presence, little is known about the functions of the PIR proteins. To investigate the role PIR proteins play during the erythrocytic stages of infection, the P. chabaudi model was chosen, where this gene family is termed cir. 198 cir genes were identified in the P. chabaudi genome, 86% of which clustered to form two major sub-families on the basis of sequence similarity. Quantitative RT-PCR and Illumina RNA sequencing were used to investigate cir transcription during P. chabaudi infection. Both methods detected many cir genes transcribed at low levels, as shown previously for other pirs. Three of the transcribed cir genes were selected for recombinant protein expression in the yeast Pichia pastoris: PCHAS_000100, PCHAS_070130 and PCHAS_040110. Soluble PCHAS_000100 was used for measurements of CIR secondary structure. Conserved and sub-family specific peptides were also synthesized. Antibodies present in the sera of P. chabaudi immune mice recognized all CIR proteins and peptides. Polyclonal antibodies were used to determine CIR localization by confocal microscopy and flow cytometry. Whilst most CIRs were located within the parasites, some CIRs were also found on the infected erythrocyte surface of mature trophozoites. In addition, CIRs were detected at the apical end of merozoites. These results imply that CIR proteins are exposed to the immune system during P. chabaudi infection and are antigenic, yet immunization with most CIR proteins and peptides did not protect mice from P. chabaudi infection. Upon P. chabaudi challenge of mice immunized with CIR sub-family specific reagents, increased levels of cir transcripts belonging to the other major sub-family were detected. This may explain why few differences in parasitaemia were observed. The exception was observed during P. chabaudi challenge of mice immunized with PCHAS_000100, which were able to clear parasitaemia earlier than controls.
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Lynch, Catherine. "The calcitonin gene peptide family in health and malignant disease". Thesis, Imperial College London, 1988. http://hdl.handle.net/10044/1/47162.
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Jawdekar, Gauri W. "Transcriptional regulation of the human small nuclear RNA gene family". Diss., Connect to online resource - MSU authorized users, 2006.
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Thesis (Ph. D.)--Michigan State University. Dept. of Microbiology and Molecular Genetics, 2006.Title from PDF t.p. (viewed on June 19, 2009) Includes bibliographical references. Also issued in print.
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Huang, Li-Fen. "Molecular analysis of an acid invertase gene family in Arabidopsis". [Gainesville, Fla.] : University of Florida, 2006. http://purl.fcla.edu/fcla/etd/UFE0013827.
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