Download or read book RNA Splicing Regulation in Drosophila Melanogaster written by Angela Norie Brooks and published by . This book was released on 2011 with total page 236 pages. Available in PDF, EPUB and Kindle. Book excerpt: A majority of metazoan genes contain introns in their primary transcripts (pre-mRNA) that require removal by the spliceosome--a cellular complex composed of protein and RNA. Upon removal of introns from the primary transcript, the remaining exonic portion of the transcript is spliced together. It is essential to remove the correct intronic portion of a primary transcript in order to produce the desired product, typically a protein-coding mRNA. Pre-mRNAs are alternatively spliced when different intron boundaries are used by the spliceosome, thus creating different mRNA products. Alternative splicing allows for an additional step of gene regulation by producing transcript isoforms that can be differentially processed in a particular tissue or developmental time point. Alternative splicing is primarily regulated by RNA binding proteins that bind to pre-mRNA and act to recruit or inhibit the spliceosome at specific splice sites. A central aim of this work is to gain a better understanding of splicing regulation by the identification and characterization of protein regulators of splicing and cis-acting splicing regulatory sequences in the model organism, Drosophila melanogaster. To identify splicing regulatory elements, many previous studies in vertebrate genomes have used computational methods. In collaboration with Anna I. Podgornaia, I applied such an approach to predict splicing regulatory elements in Drosophila melanogaster and compared them with elements found in vertebrates. I identified 330 putative splicing enhancer sequences enriched near weak 5' and 3' splice sites of constitutively spliced introns. I found that a significant proportion (58%) of D. melanogaster enhancers were previously reported as splicing enhancers in vertebrates. To provide additional evidence for the function of the intronic splicing enhancers (ISEs), I identified intronic hexamers significantly enriched within sequences phylogenetically conserved among 15 insect species. This analysis uncovered 73 putative ISEs that are also enriched in conserved regions of the D. melanogaster genome. The functions of nine enhancer sequences were verified in a heterologous splicing reporter by Julie L. Aspden, demonstrating that these sequences are sufficient to enhance splicing in vivo. Taken together, these data identify a set of predicted positive-acting splicing regulatory motifs in the Drosophila genome and highlight those regulatory sequences that are present in distant metazoan genomes. To identify and characterize splicing regulators, collaborators and I have combined RNAi and RNA-Seq to identify exons that are regulated by 58 known or putative splicing regulators. To identify and quantify alternative splicing events from RNA-Seq data, I developed the JuncBASE (Junction Based Analysis of Splicing Events) software package. For a pilot study, I identified 404 splicing events significantly affected upon depletion of pasilla. Preliminary analysis showed 879 splicing events affected by at least one of the 57 other proteins. The sequence regions upstream and within Pasilla-repressed exons and downstream of Pasilla-activated exons are enriched for YCAY repeats, which is consistent with the location of these motifs near regulated exons of the mammalian ortholog, Nova. Thus, the RNA regulatory map of Pasilla and Nova is highly conserved between insects and mammals despite the fact that the pre-mRNAs that are regulated by Pasilla and Nova are almost entirely non-overlapping. This observation strongly suggests that the regulatory codes of individual RNA binding proteins are nearly immutable, yet the regulatory modules controlled by these proteins are highly evolvable. I also present RNA regulatory maps for the four hnRNP proteins: hrp36, hrp38, hrp40, and hrp48. Lastly, I examine splicing regulation throughout the life cycle of D. melanogaster. Using transcriptome data from 30 developmental time points produced by collaborators from the modENCODE Consortium, I identified a total of 23,859 alternative splicing events in Drosophila, taking into account all transcript information from D. melanogaster annotations, short sequenced reads (Illumina RNA-Seq), sequenced cDNA, long RNA-Seq reads (454 RNA-Seq) from adult flies, and short read sequences of rRNA-depleted RNA from embryonic time points. I observed that 60.7% of intron-containing genes in D. melanogaster are alternatively spliced. Using only the Illumina RNA-Seq reads throughout development, 21,216 splicing events were expressed and 13,951 events were differentially spliced in at least one time point. I also observed exons with similar patterns of splicing changes throughout development as well as sex-biased alternative splicing. Integrating information from our pasilla study, I also observed correlations of pasilla gene expression with alternative splicing changes of its target exons throughout development.
Download or read book Regulation of Alternative Splicing in Drosophila Melanogaster written by Jefferson Matthew Taliaferro and published by . This book was released on 2012 with total page 167 pages. Available in PDF, EPUB and Kindle. Book excerpt: The patterns and mechanisms by which eukaryotic cells regulate the expression of their genetic information are highly complex and intricate. The transmittance of this information from nuclear repository to cytoplasmic translation contains within it several steps, including the selective removal and concomitant joining of pieces of information in a process called alternative splicing. The projects detailed within this document describe the regulation of alternative splicing through the interaction of specific proteins with specific pre-mRNA transcripts. The Rio lab has studied PSI, a protein involved in the regulation of the P element transposase transcript, for many years. It has since been shown to regulate the splicing of hundreds of other transcripts. The experiments described here look at the organization of PSI and other proteins on the P element transcript by site-specific labeling of the transcript using radioactive 32P. We also investigate two phosphorylation events of PSI, identifying the kinases responsible and demonstrate that these events may change the protein-protein interaction partners of PSI. It has become increasingly apparent that alternative splicing may not only be regulated by protein/RNA interactions, but also by RNA/RNA interactions. To probe this, we designed experiments to test if some well-known small RNA-associated proteins are regulating alternative splicing. Using splice junction microarrays, we determined that Argonaute-2 (Ago-2) regulated the splicing of over 100 splice junctions, and further experiments using ChIP-seq and mRNA-seq of Ago-2 mutants revealed that Ago-2 also has a role in transcriptional repression, possibly through being incorporating in complexes composed of polycomb-group genes. We also used CLIP-seq to determine the RNA binding profile and preferences of Ago-2 in Drosophila tissue culture cells. Finally, we characterized the functions of a Drosophila specific splicing factor called LS2. LS2 is orthologous to the highly conserved splicing factor dU2AF50, but its origin through retroduplication and subsequent divergence to acquire distinct sequence specificity, expression pattern, and function show it to be an interesting case in the evolution of alternative splicing regulation. This may be a mechanism that underlies the existence of some members of the large families of splicing factors, including hnRNP proteins and SR proteins. That is, by duplicating functional copies of genes, cellular systems create new proteins to tinker with and acquire new functions while keeping the former functionality and stability of the parent protein. While these projects are essentially independent of each other, they all fall under the umbrella of protein regulation of RNA metabolism and hopefully contribute to a more complete understanding of the regulation of gene expression.
Download or read book The Regulation of Alternative Pre MRNA Splicing of TAF1 in Drosophila Melanogaster written by Matthew S. Marengo and published by . This book was released on 2008 with total page 230 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Drosophila Melanogaster RNA Splicing Factor B52 written by Mary Ellen Kraus and published by . This book was released on 1995 with total page 378 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Gene Regulation Via Alternative Splicing and Nonsense mediated MRNA Decay written by Richard Edward Green and published by . This book was released on 2005 with total page 442 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Transcriptional and Alternative RNA Splicing Regulation of Myosin Heavy Chain Gene Expression in Drosophila written by Elizabeth Lee George and published by . This book was released on 1988 with total page 336 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Genetic and Molecular Studies of the Drosophila Splicing Factor B52 written by Huijun Zhou Ring and published by . This book was released on 1995 with total page 294 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Regulation of Alternative Splicing in Drosophila written by Jenny Marie Kreahling and published by . This book was released on 2005 with total page 450 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Transcription and Splicing written by B. D. Hames and published by Oxford University Press, USA. This book was released on 1988 with total page 238 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book gives a co-ordinated review of our present knowledge of eukaryotic RNA synthesis.
Download or read book In vitro and In vivo Analyses of Alternative Splicing of 3 End Transcripts of the Drosophila Melanogaster Muscle Myosin Heavy Chain Gene written by Dorothy Dianne Hodges and published by . This book was released on 1992 with total page 558 pages. Available in PDF, EPUB and Kindle. Book excerpt: Up to 480 isoforms of Drosophila muscle myosin heavy chain (MHC) can be generated by the process of alternative splicing. In order to better understand the regulation of MHC expression, we have analyzed the alternative splicing of MHC 3' end transcripts in vitro and in vivo. In Chapter 1 we describe the development and use of a Drosophila in-vitro splicing system to study the alternative splicing of penultimate exon 18. We demonstrate that pre-mRNA is spliced to exclude exon 18, as occurs in embryonic and larval muscle in vivo. However, when the 5' and 3' splice sites of exon 18 are modified to improve their binding to constitutive splicing factors, exon 18 is efficiently spliced to both flanking exons, as occurs in adult muscles in vivo. In Chapter 2 we express similarly modified transcripts in vivo using P element mediated germ line transformation. Mini-gene transcripts in which both splice sites of exon 18 are improved are now spliced to include exon 18 in larvae, as well as in adults. This is a complete splicing switch; all mRNAs typical of the normal larval splicing pattern have been eliminated. We also demonstrate that the correct 3' splice site of exon 18 is not utilized by the larval splicing machinery, even when the competing downstream 3' splice site is eliminated. Analysis of MHC [Delta] Int 17 mini-gene transcript splicing determined that intron 17 sequences are needed for intron 18 removal in larvae and adults. We also present results of cloning and sequencing the distantly related D. virilis MHC gene. Large stretches of non-coding sequences within exon 18 and a pyrimidine rich element in intron 17 are conserved between the D. virilis and D. melanogaster MHC genes. Mini-gene transcripts lacking most of the conserved exon 18 sequences were spliced in the correct stage-specific manner in vivo. However, analysis of splicing of mini-gene transcripts lacking the polypyrimidine sequence confirmed that it is essential for correct inclusion of exon 18 in adult mRNA, and suggests that binding of adult-specific, transacting factors to this element may mediate recognition and utilization of the weak 3' splice site of exon 18.
Download or read book Studies on the RRM type RNA Binding Protein Gene Family in Drosophila Melanogaster written by Young-Joon Kim and published by . This book was released on 1992 with total page 412 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Regulation of NeurexinIV MRNA Splicing in the Nervous System of Drosophila Melanogaster written by Floriano Moutinho Rodrigues and published by . This book was released on 2011 with total page 382 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Sex specific Transcript Complexity in the Neural System of Drosophila Melanogaster written by Carmen Mohr and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Analysis of the Regulation of Alternative Splicing of Myosin Alkali Light Chain Transcipts in Drosophila Melanogaster written by Efthimios Makis Charalambous Skoulakis and published by . This book was released on 1990 with total page 560 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Post transcriptional Regulation on Neuronal Polypyrimidine Tract Binding Protein Reprograms Alternative Splicing in Neural and Muscular Cells written by Paul Lawrence Boutz and published by . This book was released on 2006 with total page 328 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book In vitro and In vivo Analyses of Alternative Splicing of 3 End Transcripts of the Drosophila Melanogaster Muscle Myosin Heavy Chain Gene written by and published by . This book was released on 1992 with total page 520 pages. Available in PDF, EPUB and Kindle. Book excerpt: Up to 480 isoforms of Drosophila muscle myosin heavy chain (MHC) can be generated by the process of alternative splicing. In order to better understand the regulation of MHC expression, we have analyzed the alternative splicing of MHC 3' end transcripts in vitro and in vivo. In Chapter 1 we describe the development and use of a Drosophila in-vitro splicing system to study the alternative splicing of penultimate exon 18. We demonstrate that pre-mRNA is spliced to exclude exon 18, as occurs in embryonic and larval muscle in vivo. However, when the 5' and 3' splice sites of exon 18 are modified to improve their binding to constitutive splicing factors, exon 18 is efficiently spliced to both flanking exons, as occurs in adult muscles in vivo. In Chapter 2 we express similarly modified transcripts in vivo using P element mediated germ line transformation. Mini-gene transcripts in which both splice sites of exon 18 are improved are now spliced to include exon 18 in larvae, as well as in adults. This is a complete splicing switch; all mRNAs typical of the normal larval splicing pattern have been eliminated. We also demonstrate that the correct 3' splice site of exon 18 is not utilized by the larval splicing machinery, even when the competing downstream 3' splice site is eliminated. Analysis of MHC [Delta] Int 17 mini-gene transcript splicing determined that intron 17 sequences are needed for intron 18 removal in larvae and adults. We also present results of cloning and sequencing the distantly related D. virilis MHC gene. Large stretches of non-coding sequences within exon 18 and a pyrimidine rich element in intron 17 are conserved between the D. virilis and D. melanogaster MHC genes. Mini-gene transcripts lacking most of the conserved exon 18 sequences were spliced in the correct stage-specific manner in vivo. However, analysis of splicing of mini-gene transcripts lacking the polypyrimidine sequence confirmed that it is essential for correct inclusion of exon 18 in adult mRNA, and suggests that binding of adult-specific, transacting factors to this element may mediate recognition and utilization of the weak 3' splice site of exon 18.
Download or read book Regulation of Translation and Alternative Splicing by the Drosophila RNA binding Protein Sister of Sex lethal written by Rebecca Moschall and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
