Download or read book Transcriptional Regulation in the Embryonic Central Nervous System of Drosophila written by Robert Graham Franks and published by . This book was released on 1994 with total page 270 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Transcriptional Regulation of Neuronal Differentiation in the Drosophila Central Nervous System written by Haluk Lacin and published by . This book was released on 2010 with total page 183 pages. Available in PDF, EPUB and Kindle. Book excerpt: The central nervous system is the most complex and highly organized tissue in animals; composed of thousands of neurites connected in specific and highly reproducible ways. My thesis research has focused on the generation of neuronal diversity: specifically how neurons adopt individual, often unique, identities. Work in many labs has revealed that a large set of transcription factors act in combinatorial manner to specify the fate of individual neurons or small groups of neurons. However, in most cases, it remains unclear how individual or specific combinations of transcription factors directly control the terminal differentiation of neurons via the regulation of different genes, such as neurotransmitters. My thesis work has focused on the identification and characterization of new members of the combinatorial code of transcription factor and on initial attempts to link these transcription factors to the expression and activity of genes that contribute directly to neuronal differentiation. In chapter 2, I describe the identification and characterization of Dbx, a homedomain-containing transcription factor, expressed in a mixture of progenitor cells and a subset of GABAergic interneurons. I show that Dbx is expressed in many interneurons that are sibling to motor neurons, and that Dbx is required to promote the development of these interneurons via cross-repressive interactions with Eve and Hb9, which are expressed in the sibling motor neurons. In chapter 3, I detail the identification of FoxD, a transcription factor that is positively regulated by the homeodomain-containing transcription factor Hb9 in the Drosophila CNS. FoxD is expressed in a subset of Hb9 positive neurons and also in all octopaminergic neurons in the Drosophila embryonic CNS. I have identified the enhancers that drive expression in these neurons and have recently generated two mutant alleles of foxD. Loss of foxD appears to result in hyperactivity, which is most pronounced in males. As octopamine is the fly equivalent of norepinephrine, these results suggest that FoxD may function in specific cells to regulate the synthesis and release of octopmaine. Thus, my thesis has identified two members of the combinatorial code of transcription factors that govern neuronal identity. In addition, it has begun to place the functions of these genes within the genetic regulatory hierarchy of this code and started to link the function of individual transcription factors to the regulation of terminal differentiation genes and animal behavior.

Download or read book Analysis of Axon Guidance in the Embryonic Central Nervous System of Drosophila Melanogaster written by Vicki L. McGovern and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: The goal of developmental neurobiology is to understand how a complex nervous system is wired. During development of the central nervous system (CNS) neural connections are assembled in a highly stereotyped fashion. How do axons find their targets with such accuracy? We know that axon migration is direct by attractive and repulsive guidance cues located in the extracellular environment. While many guidance molecules have been identified, we are only just beginning to understand the mechanisms of axon guidance. In order to identify additional genes involved in axon guidance and CNS development we performed a misexpression screen. Using P-elements and the UAS/GAL4 system, transcription of endogenous genes was induced in the embryonic CNS. Misexpression phenotypes were then identified immunohistochemically with two monoclonal antibodies: BP102, a general axon marker, and 1D4, which labels a subset of axon pathways. Over 4100 individual P-element insertion lines were screened. Twenty-five insertions corresponding to 18 genes resulted in misexpression phenotypes. Genes involved in axon guidance, embryonic patterning, and cell cycle regulation were identified. Several transcription factors that have not been previously implicated in CNS development were isolated and characterized as well. The identification of these transcription factors is intriguing since little is known about the transcriptional regulation of axon guidance genes. Additionally, we have studied the regulation of the previously identified guidance molecule Commissureless (Comm). Comm is necessary for proper axon guidance at the CNS midline of the Drosophila embryo. In the absence of Comm, commissural axons fail to cross the midline and instead make ispilateral projections on their respective sides of the midline. Using mosaic analysis, we have identified a cell autonomous neuronal requirement for Comm. Clones containing mutant alleles of comm formed commissural projections at a statistically significant reduced frequency when compared to wild type clones. This result suggests that regulation of Comm expression in neurons is critical for Comm's function in axon guidance at the CNS midline. These studies have both advanced the understanding of the regulation of Comm, and have identified new potential regulators of guidance molecules.

Download or read book Transcriptional Control of Drosophila Neuromuscular Connectivity and the Identification of a Putative Central Nervous System Midline Cell Adhesion Molecule written by Song Hu and published by . This book was released on 1995 with total page 406 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Generation of Cellular Pattern and Fate in the Drosophila Embryonic Central Nervous System written by James Benjamin Skeath and published by . This book was released on 1993 with total page 324 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Brain Development in Drosophila melanogaster written by Gerhard Martin Technau and published by Springer Science & Business Media. This book was released on 2009-01-08 with total page 173 pages. Available in PDF, EPUB and Kindle. Book excerpt: The fruitfly Drosophila melanogaster is an ideal model system to study processes of the central nervous system This book provides an overview of some major facets of recent research on Drosophila brain development.

Download or read book Genetic Mechanisms Regulating the Spatiotemporal Modulation of Proliferation Rate and Mode in Neural Progenitors and Daughter Cells during Embryonic CNS Development written by Behzad Yaghmaeian Salmani and published by Linköping University Electronic Press. This book was released on 2018-05-09 with total page 63 pages. Available in PDF, EPUB and Kindle. Book excerpt: The central nervous system (CNS) is a hallmark feature of animals with a bilateral symmetry: bilateria and can be sub-divided into the brain and nerve cord. One of the prominent properties of the CNS across bilateria is the discernible expansion of its anterior part (brain) compared with the posterior one (nerve cord). This evolutionarily conserved feature could be attributed to four major developmental agencies: First, the existence of more anterior progenitors. Second, anterior progenitors are more proliferative. Third, anterior daughter cells, generated by the progenitors, are more proliferative. Forth, fewer cells are removed by programmed cell death (PCD) anteriorly. My thesis has addressed these issues, and uncovered both biological principles and genetic regulatory networks that promote these A-P differences. I have used the Drosophila and mouse embryonic CNSs as model systems. Regarding the 1st issue, while the brain indeed contains more progenitors, my studies demonstrate that this only partly explains the anterior expansion. Indeed, with regard to the 2nd issue, my studies, on both the Drosophila and mouse CNS, demonstrate that anterior progenitors divide more extensively. Concerning the 3rd issue, in Drosophila we identified a gradient of daughter proliferation along the AP axis of the developing CNS with brain daughter cells being more proliferative. Specifically, in the brain, progenitors divide to generate a series of daughter cells that divide once (Type I), to generate two neurons or glia. In contrast, in the nerve cord, progenitors switch during later stages, from first generating dividing daughters to subsequently generating daughters that directly differentiate (Type 0). Hence, nerve cord progenitors undergo a programmed Type I->0 proliferation switch. In the Drosophila posterior CNS, this switch occurs earlier and is more prevalent, contributing to the generation of smaller lineages in the posterior regions. Similar to Drosophila, in the mouse brain we also found that progenitor and daughter cell proliferation was elevated and extended into later developmental stages, when compared to the spinal cord. DNA-labeling experiments revealed faster cycling cells in the brain when compared to the nerve cord, in both Drosophila and mouse. In both Drosophila and mouse, we found that the suppression of progenitor and daughter proliferation in the nerve cord is controlled by the Hox homeotic gene family. Hence, the absence of Hox gene expression in the brain provides a logical explanation for the extended progenitor proliferation and lack of Type I->0 switch. The repression of Hox genes in the brain is mediated by the histonemodifying Polycomb Group complex (PcG), which thereby is responsible for the anterior expansion. With respect to the 4th issue, we found no effect of PCD on anterior expansion in Drosophila, while this cannot be asserted for the mouse embryonic neurodevelopment as there are no genetic tools to abolish PCD effectively in mammals. Taken together, the studies presented in this thesis identified global and evolutionarily-conserved genetic programs that promote anterior CNS expansion, and pave the way for understanding the evolution of size along the anterior-posterior CNS axis.

Download or read book Transcriptional Regulation of Early Progenitor Competence in the Drosophila Central Nervous System written by Khoa Dang Tran and published by . This book was released on 2010 with total page 208 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Patterning the Drosophila Embryonic Central Nervous System written by Jocelyn Ann McDonald and published by . This book was released on 1998 with total page 264 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Morphology and Gene Expression Patterning of Primary and Secondary Neurons in the Drosophila Brain written by Diana Amy Shy and published by . This book was released on 2009 with total page 150 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Comprehensive Developmental Neuroscience Patterning and Cell Type Specification in the Developing CNS and PNS written by P.A. Kuert and published by Elsevier Inc. Chapters. This book was released on 2013-05-06 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Transcription Factors in the Nervous System written by Gerald Thiel and published by John Wiley & Sons. This book was released on 2006-05-12 with total page 505 pages. Available in PDF, EPUB and Kindle. Book excerpt: This first book to cover neural development, neuronal survival and function on the genetic level outlines promising approaches for novel therapeutic strategies in fighting neurodegenerative disorders, such as Alzheimer's disease. Focusing on transcription factors, the text is clearly divided into three sections devoted to transcriptional control of neural development, brain function and transcriptional dysregulation induced neurological diseases. With a chapter written by Nobel laureate Eric Kandel, this is essential reading for neurobiologists, geneticists, biochemists, cell biologists, neurochemists and molecular biologists.

Download or read book Molecular Genetic Characterization of Jing During Drosophila Embryonic Central Nervous System and Tracheal System Development written by Yalda Sedaghat and published by . This book was released on 2005 with total page 582 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Embryonic Development of Drosophila melanogaster written by Jose A. Campos-Ortega and published by Springer Science & Business Media. This book was released on 2013-03-09 with total page 237 pages. Available in PDF, EPUB and Kindle. Book excerpt: " . . . but our knowledge is so weak that no philosoph er will ever be able to completely explore the nature of even a fly . . . " * Thornas Aquinas "In Syrnbolurn Apostolorum" 079 RSV p/96 This is a monograph on embryogenesis of the fruit fly Drosophi la melanogaster conceived as a reference book on morphology of embryonie development. A monograph of this extent and con tent is not yet available in the literature of Drosophila embryolo gy, and we believe that there is areal need for it. Thanks to the progress achieved during the last ten years in the fields of devel opmental and molecular genetics, work on Drosophila develop ment has considerably expanded creating an even greater need for the information that we present here. Our own interest for wildtype embryonie development arose several years ago, when we began to study the development of mutants. While those studies were going on we repeatedly had occasion to state in sufficiencies in the existing literature about the embryology of the wildtype, so that we undertook investigating many of these problems by ourselves. Convinced that several of our colleagues will have encountered similar difficulties we decided to publish the present monograph. Although not expressely recorded, Thomas Aquinas probably referred to the domestic fly and not to the fruit fly. Irrespective of which fly he meant, however, we know that Thomas was right in any case.

Download or read book Molecular and Genetic Studies of Robo2 Transcriptional Regulation in the Central Nervous System of Drosophila Melanogaster written by Muna Abdal-Rahim Abdal-Rhida and published by . This book was released on 2021 with total page 320 pages. Available in PDF, EPUB and Kindle. Book excerpt: Drosophila Robo2 axon guidance receptor is a member of the evolutionarily conserved Roundabout (Robo) protein family that is involved in directing axons that cross the midline to the other side of the animal body. Robo2 roles mainly depend on two factors: The functional domains of the Robo2 protein, which is extensively studied, and the dynamic transcription of Robo2 in various subsets of cells throughout embryogenesis which is not fully understood. Thus, knowing Robo2 enhancers that transcriptionally regulate Robo2 during embryogenesis is significant. To investigate Robo2 potential enhancers, we screened 17 transgenic lines of Drosophila that were generated by Janelia Research Center. These lines contain 17 fragments distributed within and around the Robo2 gene. We identified six fragments that regulated Robo2 expression by the GAL4-UAS-GFP system suggesting that they were promising enhancers. Using these identified regulatory fragments in addition to three fragments generated in our lab, we built the HA-Robo2 transgenic constructs. These constructs were introduced into Drosophila which allowed us to test Robo2 expression and its dependent axon guidance phenotypes in the embryonic CNS. GMR28G05 and GMR28F02 fragments showed the strongest Robo2 expression in the lateral pathway. To further study these fragments, we introduced them separately or together into Robo2 null mutant background. We found that Robo2's dynamic expression pattern is specified by multiple regulatory regions. We utilized these fragments to generate and characterize an equivalent set of Robo2 transgenes expressing the axonal marker TauMyc instead of the HA-Robo2 and hsp70 promoter instead of Robo2 promoter. The results show that GMR28F02 fragment drove strong expression of TauMyc in a subset of the lateral neurons, cell bodies, and commissural axon from which Robo2 protein is expressed. CRISPR/Cas9 system was used to further investigate the importance of our findings. Cas9 protein and specific gRNAs were used to target and delete Robo2 potential enhancers (GMR28G05 and GMR28F02) separately or together. Applying bioinformatics tools and literature I predicted three transcription factors (Hb9, Nkx6.1, and Lhx2) that have a high probability to bind Robo2 potential enhancers. In summary, Robo2 has potential enhancers located in the first intron and upstream of the gene, and multiple enhancers more efficiently regulated Robo2 expression in Drosophila.

Download or read book The Regulation of Commissureless in the Embryonic CNS of Drosophila Melanogaster written by Casey C. Jowdy and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: During development the precise wiring of the nervous system is dependent on the correct repertoire of axon guidance molecules being expressed at the right time and place. In the CNS of D. melanogaster, Comm and Robo play important roles in regulating axons at the midline. To date much has been studied about how Comm regulates Robo, but little is known about how Comm is regulated in the CNS. Comm is dynamically expressed in an off, on, and off again fashion in contralaterally projecting axons and is not expressed in ipsilateral projecting axons. Our hypothesis is the dynamic spatial and temporal regulation of Comm is at the transcriptional level.

Download or read book Regulation of Pattern Formation During Development of the Drosophila Peripheral Nervous System written by Eric Cheng-pin Lai and published by . This book was released on 1999 with total page 660 pages. Available in PDF, EPUB and Kindle. Book excerpt: