GENETICS AND EVOLUTION OF MORPHOLOGY IN DROSOPHILA

果蝇形态学的遗传学和进化

• 批准号: 2184699
• 负责人: CATHY C LAURIE
• 金额: $ 20.81万
• 依托单位: DUKE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1992
• 资助国家: 美国
• 起止时间: 1992-05-01 至 1996-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2184699
• 关键词: DNA; Drosophilidae; biochemical evolution; chromosome walking; developmental genetics; gene expression; gene mutation; genetic markers; genetic regulatory element; genetic transcription; male; molecular cloning; morphology; northern blottings; nucleic acid hybridization; nucleic acid sequence; reproductive development; sex differentiation; species difference; transposon /insertion element

The morphology of animal genitalia and associated structures that function in sperm transfer is often very complex and divergent among closely related species, particularly in insects. For example, Drosophila melanogaster has 7 sibling species, among which the only reliable morphological characters for identification are the male genitalia. Because these secondary sexual characteristics appear to be among the first characters to change in the evolution of new species, they provide a number of advantages for investigating the genetic and molecular basis of interspecific differences in morphology. The proposed project has 3 specific aims. (1) One aim is to determine the genetic architecture of the differences in male genitalia between D. mauritiana and D. simulans, which belong to the melanogaster subgroup of sibling species. The approach is to mark approximately 70 segments of the genome of one species with P-element insertions containing eye color marker. Each segment will be introgressed individually into the genome of the other species by repeated backcrossing for 26 generations and then made homozygous. Analysis of variation in genitalic characters among these lines will provide an estimate of the number of genes that affect these traits and the relative magnitude of those effects. In some cases, the importance of dominance and epistasis will also be investigated. (2) Genes of D. melanogaster that are involved in the development of the male genitalia will be identified by enhancer detector screening and P- element mutagenesis. Enhancer detector insertions that show a different pattern of expression in male and female genital discs potentially identify genes involved in producing the sexually dimorphic genitalia. This potential will be investigated by inducing mutations in nearby genes through imprecise excisions of the P-element. (3) When loss of function genitalic mutants are found, their possible role in causing interspecific differences will be investigated through a hybridization test. Any gene that appears to contribute substantially to these differences will be cloned and its molecular structure characterized. The molecular basis of these differences can then be investigated by interspecific gene transfer using P-element transformation. With this information, one can begin to answer long standing questions about the relative importance of structural and regulatory genetic changes in morphological evolution.

动物生殖器的形态和相关的结构， 精子移植的功能往往非常复杂和不同。 在亲缘关系密切的物种之间，特别是在昆虫中。为 例如，果蝇有7个近亲物种，其中 用于鉴定的唯一可靠的形态特征是 男性生殖器。因为这些第二性征 似乎是进化中最早发生变化的角色之一 在新物种中，它们为 探讨种间遗传和分子基础 形态上的差异。建议的项目有3个具体的 目标。(1)一个目标是确定人类的遗传结构 毛滴虫和毛滴虫雄性生殖器的差异。 类人猿，属于兄弟姐妹中的黑猩猩亚群 物种。方法是标记大约70个片段 一个含有眼睛的P元件插入的物种的基因组 彩色标记。每个片段都将被单独介绍到 通过重复回交26次获得了其他物种的基因组 几代人，然后变得纯合。对中国经济发展的变异分析 这些品系中的生殖器字符将提供 影响这些性状的基因数量和相对数量 这些影响的大小。在某些情况下， 优势和上位性也将被调查。(2)D. 与男性发育有关的黑腹蛇 生殖器将通过增强子检测器筛查和P- 元素突变。增强子检测器插入显示 男性和女性生殖盘的不同表达模式 潜在地识别与产生有性繁殖有关的基因 二态生殖器。这一潜力将由以下机构调查 通过不精确的切除诱导邻近基因的突变 P元素。(3)功能丧失时，生殖器突变体 发现了它们在造成种间差异方面的可能作用 将通过杂交测试进行调查。任何基因 似乎对这些差异有很大贡献的将是 克隆并鉴定了其分子结构。分子 这些差异的基础可以通过 利用P元素转化进行种间基因转移。使用 这些信息，人们可以开始回答长期存在的问题 关于结构基因和调控基因的相对重要性 形态进化的变化。