Author: Vasily SysoevPublisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
RNA-binding Proteins in the Early Drosophila Embryo
Author: Vasily SysoevMechanisms of Smaug-mediated Post-transcriptional Regulation in the Early Drosophila Embryo
Author: Benjamin Douglas PinderGenome-Wide Analysis of Translation in the Early Drosophila Embryo
Author: Jason DumelieRegulation of MRNA Stability by the RNA-binding Protein Pumilio During Early Drosophila Embryogenesis
Author: Alexander John MarsolaisPublisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
The maternal-to-zygotic transition (MZT) is a characteristic phase of early metazoan development where control of embryogenesis transitions from products encoded by the mother to those encoded by the zygotic genome. Post-transcriptional regulation (PTR) plays a critical role in the MZT, particularly in the clearance of maternal mRNAs. Mechanisms of maternal transcript decay that rely exclusively on maternal protein factors and function early during the MZT, as well as mechanisms that require zygotic factors and function later during the MZT, have been characterized. The Drosophila embryo has long-served as a model for the MZT. The RNA-binding protein (RBP) SMAUG (SMG) has been shown to function during the early (maternal) phase of degradation. In contrast, computational methods suggest the RBP PUMILIO (PUM) functions in the late (zygotic) phase of maternal mRNA degradation. Such a role is curious as PUM is maternally-contributed and functional during the maternal (early) phase of embryogenesis. I show here that: 1) PUM is required for the degradation of approximately 500 maternal mRNAs during the late (zygotic) wave of degradation; 2) degradation of PUM target mRNAs is likely delayed to the late (zygotic) phase due to the presence of sub-optimal PUM binding sites within these target mRNAs, 3) degradation of PUM targets is dependent on additional factors such as the RBP BRAIN TUMOUR (BRAT) and a core component of the RNAi machinery, ARGONAUTE 1 (AGO1); and 4) a critical function of PUM appears to be clearance of smg mRNA, since in pum mutant embryos SMG protein persists post-MZT and is associated with an inappropriate down-regulation of SMG target transcripts. Taken together, these data support a multi-factorial view of RBP function, in which the activity of a given RBP is determined by other RBPs associated with a particular mRNA.
Regulation of Metabolism in Early Drosophila Embryos by the Smaug RNA-binding Protein
Author: Zhiyong YangPublisher:
ISBN:
Category :
Languages : en
Pages : 0
Book Description
Smaug is a RNA-binding protein that regulates translational repression and/or degradation of its targets, and is required for the elimination of a large number of maternal transcripts in early Drosophila embryos. Here, I explored a novel role of Smaug in regulation of Smaug in early embryos. Previous experiments identified mRNAs encoding glycolytic enzymes as associated with Smaug. I found that mRNAs encoding these enzymes have predicted Smaug recognition elements (SREs) and are destabilized by Smaug. Furthermore, I performed enzyme activity assays and showed increased activity of several glycolytic enzymes in smaug mutants. Experiments comparing the metabolome of wild-type and smaug mutant embryos implicated Smaug in an array of metabolic pathways including glycolysis.
Myofibrillogenesis
Author: Dipak K. DubePublisher: Springer Science & Business Media
ISBN: 9780817642266
Category : Science
Languages : en
Pages : 304
Book Description
Myofibrillogenesis has been studied extensively over the last 100 years. Until recently, we have not had a comprehensive understanding of this fundamental process. The emergence of new technologies in molecular and cellular biology, combined with classical embryology, have started to unravel some of the complexities of myofibril assembly in striated muscles. In striated muscles, the contractile proteins are arranged in a highly ordered three dimensional lattice known as the sarcomere. The assembly of a myofibril involves the precise ordering of several proteins into a linear array of sarcomeres. Multiple isoforms in many of these proteins further complicate the process, making it difficult to define the precise role of each component. This volume has been compiled as a comprehensive reference on myofibrillogenesis. In addition, the book includes reviews on myofibrillar disarray under various pathological conditions, such as familial hypertrophic cardiomyopathy (FHC), and incorporates a section on the conduction system in the heart. Much of the information in this volume has not been described elsewhere. Presented in a manner to be of value to students and teachers alike, "Myofibrillogenesis" will be an invaluable reference source for all in the fields of muscle biology and heart development.
Characterization of the N-terminal Region of the RNA-Binding Protein Smaug in Post-transcriptional Regulation During Drosophila Embryogenesis
Author: Matthew ChengSystematic Analysis of Protein-RNA Interactions in Drosophila
Author: John LaverPublisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Post-transcriptional regulation of gene expression, through the control of mRNA splicing, polyadenylation, nuclear export, localization, translation, and stability, is essential for achieving appropriate temporal and spatial patterns of protein expression. This regulation is mediated by trans-acting factors, such as RNA-binding proteins (RBPs) and non-coding RNAs, which associate with specific mRNA targets through the recognition of sequence- or structure-based cis-elements present in the transcripts. The genomes of most organisms encode hundreds of RBPs, each of which likely associates with hundreds of mRNAs. Thus, a genome-wide view of the regulation being mediated by all trans-factors is essential for a complete understanding of post-transcriptional control. While post-transcriptional regulation is crucial in all biological systems, it has a particularly prominent role during early embryo development, as during this time there is no transcription from the zygotic genome of the embryo, and, thus, gene expression and development is controlled entirely post-transcriptionally. In this thesis, I describe my efforts towards obtaining a global understanding of post-transcriptional regulation in early Drosophila melanogaster embryos, through the development and use of synthetic antibodies as tools to identify, genome-wide, RBP-mRNA interactions. First, I demonstrated that synthetic antibodies generated against RBPs can be used as tools to identify RBP-associated mRNAs through immunoprecipitation-based approaches, or, conversely, to disrupt RBP-mRNA interactions. I then used synthetic antibodies to identify the entire complement of mRNAs associated with 3 developmentally-important RBPs: the double-stranded RBP Staufen, the TRIM-NHL protein Brain Tumor, and the PUF protein Pumilio. Computational analyses of these mRNAs revealed: (1) novel cis-elements likely mediating the mRNA-binding activity of Staufen and Brain Tumor; (2) that, unexpectedly, Brain Tumor and Pumilio function largely independently of each other in early embryos; and, (3) a novel role for Brain Tumor in promoting mRNA decay, which was demonstrated through a transcriptome-wide analysis of mRNA levels in brain tumor mutant embryos. To facilitate a truly genome-wide analysis of RBP-mRNA interactions, we developed a high-throughput pipeline for production of synthetic antibodies, and used this pipeline to generate 279 antibodies against 61 RBPs. In future this pipeline and the antibodies generated will allow for global studies of post-transcriptional regulation.
Germline Development
Author: Joan MarshPublisher: John Wiley & Sons
ISBN:
Category : Medical
Languages : en
Pages : 344
Book Description
Connects classical cellular descriptive studies with more recent work on the molecular and genetic aspects regarding germline development. Prominent scientists discuss research on a range of organisms including insects, worms, birds, fish, amphibia, mammals and green algae. Specification of germ cells, their migration to the gonads and subsequent interactions with the soma and evolutionary factors of their segregation are among the topics covered.
Author: Meryl Nelson