Molecular Genetics of Drosophila Hybrid Lethality

果蝇杂交致死率的分子遗传学

基本信息

批准号：
8974421
负责人：
DANIEL A BARBASH
金额：
$ 29.91万
依托单位：
CORNELL UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2005
资助国家：
美国
起止时间：
2005-09-01 至 2017-11-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8974421
关键词：
Affect Animals Attention Back Biological Biological Assay Conflict (Psychology)DNA Damage DNA Transposable Elements Data Development Drosophila genus Drosophila melanogaster Eukaryota Event Evolution Experimental Genetics Family Female Fertility Genes Genetic Genome Genotype Germ Cells Health Host Defense Human Human Genome Hybrids Length Mediating Meiosis Messenger RNA Modeling Molecular Molecular Evolution Molecular Genetics Mutation Oocytes Orthologous Gene Pathway interactions Pattern Performance Phenotype Population Post-Transcriptional Regulation Process Proteins Proxy Regulation Repression Research Resolution Selfish DNA Sequence Analysis Series Small RNA Structure System Testing Transcript Transgenic Organisms Variant base gene function genetic approach genome-wide hybrid gene male mutant novel strategies piRNA pressure reproductive research study segregation telomere theories

项目摘要

DESCRIPTION (provided by applicant): New species form when diverging populations become reproductively isolated. One cause of this isolation is hybrid incompatibility, the sterilit and lethality of interspecific hybrids. This proposal investigates two previously identified genes that interact to cause lethality in hybrids between the fruit fly species Drosophila melanogaster and D. simulans. Sequence analysis of both genes shows that they have evolved under adaptive evolution, a pattern also observed with other hybrid incompatibility genes. Identifying the specific selective forces causing this pattern of molecular evolution will therefore help elucidate the biological causes of speciation. This proposal is based on the recent discovery that these Drosophila hybrid incompatibility genes are required to repress transposable elements, selfish DNAs that can mobilize, reach high copy number, and cause significant damage to eukaryotic genomes. A range of genetic and molecular assays are proposed here to identify how these genes function in repressing transposable elements, including profiling the genome-wide pattern of transposition in mutant lines. Other phenotypic assays will investigate how these genes affect fertility and meiotic performance within their own host species. Attention will then turn to an integrated effort to determine how sequence divergence and adaptive evolution between species has altered specific functions of these genes. Transposable elements are a major cause of spontaneous mutation and DNA damage in eukaryotes including humans. The proposed studies will provide a high resolution view of how transposable element load contributes to host gene evolution and reproductive isolation between species.

描述（由申请人提供）：当不同的种群在生殖上被隔离时，就会形成新的物种。造成这种隔离的原因之一是杂种不亲和性、种间杂种的不育性和致死性。该提案研究了两个先前发现的基因，它们相互作用导致果蝇种果蝇和模拟果蝇之间的杂交致死。这两个基因的序列分析表明它们是在适应性进化下进化的，这种模式在其他杂交不相容性基因中也观察到。因此，识别导致这种分子进化模式的特定选择力将有助于阐明物种形成的生物学原因。该提议基于最近的发现，即这些果蝇杂交不相容基因需要抑制转座元件，即可以动员、达到高拷贝数并对真核基因组造成重大损害的自私DNA。本文提出了一系列遗传和分子测定，以确定这些基因如何在抑制转座元件中发挥作用，包括分析突变系中的全基因组转座模式。其他表型测定将研究这些基因如何影响其宿主物种内的生育力和减数分裂性能。然后，注意力将转向综合努力，以确定物种之间的序列差异和适应性进化如何改变这些基因的特定功能。转座元件是包括人类在内的真核生物自发突变和 DNA 损伤的主要原因。拟议的研究将提供转座元件负载如何促进宿主基因进化和物种间生殖隔离的高分辨率视图。