Genetic and molecular studies of early embryogenesis in Drosophila

<p>The <em>Drosophila</em> embryo is patterned by a complex interplay of zygotically expressed genes and maternally supplied components, a large number of which have been identified. However, many maternal components are encoded by essential zygotic genes whose maternal effects ar...

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Prif Awdur: Kidd, T
Awduron Eraill: Ish-Horowicz, D
Fformat: Traethawd Ymchwil
Iaith:English
Cyhoeddwyd: 1994
Pynciau:
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author Kidd, T
author2 Ish-Horowicz, D
author_facet Ish-Horowicz, D
Kidd, T
author_sort Kidd, T
collection OXFORD
description <p>The <em>Drosophila</em> embryo is patterned by a complex interplay of zygotically expressed genes and maternally supplied components, a large number of which have been identified. However, many maternal components are encoded by essential zygotic genes whose maternal effects are not amenable to conventional genetic analysis. Investigation of such genes requires the generation of homozygous mutant germ cells in chimeric females, and analysis of their embryos. The recent development of techniques which allow the efficient generation of germline clones has made the screening of zygotic lethal mutations for maternal effects more feasible. I have generated a collection of X-linked zygotic lethal mutations and used FLP recombinase catalysed mitotic recombination to look for maternal effects affecting segmentation.</p> <p>Two mutations have been recovered which have maternal effect phenotypes similar to those of the pair-rule segmentation genes. The <em>leprechaun</em> mutation affects oogenesis, so fertile females are very rare, preventing straightforward phenotypic analysis of the segmentation phenotype. Attempts to generate a rescuing duplication are described.</p> <p>The second mutation, <em>stunted</em> <em>(sun)</em>, initially gave rise to a segmentation cuticle phenotype. Subsequent attempts to reproduce the phenotype were unsuccessful as it was masked by a severe reduction in the amount of cuticle secreted, a phenotype characteristic of the neurogenic genes. Detailed analysis revealed that the primary lesion affects neither segmentation or neurogenesis. Rather, <em>sun</em><sup>+</sup> is required for cellularisation of the syncytial blastoderm and for the localisation of actin to 'caps' above the syncytial nuclei. Cloning of a candidate gene for <em>stunted</em> revealed a predicted protein product limited homology to cyclins.</p> <p>In addition to searching for novel segmentation genes, potential proteinprotein interactions of the segmentation gene <em>hairy's</em> protein product were also investigated, and a model is presented for its mode of action as a transcriptional repressor.</p>
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spelling oxford-uuid:2832c843-43ef-48bf-9674-abf1029caf782024-12-01T19:40:57ZGenetic and molecular studies of early embryogenesis in DrosophilaThesishttp://purl.org/coar/resource_type/c_db06uuid:2832c843-43ef-48bf-9674-abf1029caf78ResearchEmbryologyEnglishPolonsky Theses Digitisation Project1994Kidd, TIsh-Horowicz, DIsh-Horowicz, D<p>The <em>Drosophila</em> embryo is patterned by a complex interplay of zygotically expressed genes and maternally supplied components, a large number of which have been identified. However, many maternal components are encoded by essential zygotic genes whose maternal effects are not amenable to conventional genetic analysis. Investigation of such genes requires the generation of homozygous mutant germ cells in chimeric females, and analysis of their embryos. The recent development of techniques which allow the efficient generation of germline clones has made the screening of zygotic lethal mutations for maternal effects more feasible. I have generated a collection of X-linked zygotic lethal mutations and used FLP recombinase catalysed mitotic recombination to look for maternal effects affecting segmentation.</p> <p>Two mutations have been recovered which have maternal effect phenotypes similar to those of the pair-rule segmentation genes. The <em>leprechaun</em> mutation affects oogenesis, so fertile females are very rare, preventing straightforward phenotypic analysis of the segmentation phenotype. Attempts to generate a rescuing duplication are described.</p> <p>The second mutation, <em>stunted</em> <em>(sun)</em>, initially gave rise to a segmentation cuticle phenotype. Subsequent attempts to reproduce the phenotype were unsuccessful as it was masked by a severe reduction in the amount of cuticle secreted, a phenotype characteristic of the neurogenic genes. Detailed analysis revealed that the primary lesion affects neither segmentation or neurogenesis. Rather, <em>sun</em><sup>+</sup> is required for cellularisation of the syncytial blastoderm and for the localisation of actin to 'caps' above the syncytial nuclei. Cloning of a candidate gene for <em>stunted</em> revealed a predicted protein product limited homology to cyclins.</p> <p>In addition to searching for novel segmentation genes, potential proteinprotein interactions of the segmentation gene <em>hairy's</em> protein product were also investigated, and a model is presented for its mode of action as a transcriptional repressor.</p>
spellingShingle Research
Embryology
Kidd, T
Genetic and molecular studies of early embryogenesis in Drosophila
title Genetic and molecular studies of early embryogenesis in Drosophila
title_full Genetic and molecular studies of early embryogenesis in Drosophila
title_fullStr Genetic and molecular studies of early embryogenesis in Drosophila
title_full_unstemmed Genetic and molecular studies of early embryogenesis in Drosophila
title_short Genetic and molecular studies of early embryogenesis in Drosophila
title_sort genetic and molecular studies of early embryogenesis in drosophila
topic Research
Embryology
work_keys_str_mv AT kiddt geneticandmolecularstudiesofearlyembryogenesisindrosophila