Test for Evolution Without Sex in Bbeloid Rotifers

贝类轮虫无性进化测试

• 批准号: 9022716
• 负责人: Matthew Meselson
• 金额: $ 4.99万
• 依托单位: Harvard University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1990
• 资助国家: 美国
• 起止时间: 1990-12-01 至 1992-11-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9022716&HistoricalAwards=false
• 关键词: Test; Evolution; Without; Sex; Bbeloid

Sexual recombination as well as mutations provides the genetically variable raw material upon which evolutionary forces act in higher, more complex organisms. Thus, based upon that assumption, sex has been considered an important, almost necessary, component of the evolutionary process. However, Dr. Matthew Meselson of Harvard University describes a class of animals, Bdelloidea, which, in so far as has been determined, has no sexual genetic exchange. But, as he points out, sexual exchange may occur under rare or at least unknown circumstances and a more rigorous test is needed to confirm the fact that an organism which has been successful in evolution is lacking any mechanism for genetic exchange. He proposes to use restriction fragment length polymorphisms (RFLP) as a test. Specific species of Bdelloidea, thought to be diploid, will be selected as test organisms. Isolated DNA will be fragmented with restriction enzymes and the extent of heterozygosity will be determined. The underlying assumption is that sexual organisms homozygous their chromosomes much more rapidly than do asexual organisms. The project can be done within the one year limitation and is high risk in that if the answer is that there is little heterozygosity seen in the rotifer DNA, the organisms probably have some type of sexual mechanism and thus, are of little interest for further study. If, on the other hand, the answer is that there is a large amount of heterozygosity in their DNA, then significant insights into our understanding of evolution can be achieved by asking the proper questions.*** //

性重组和突变提供了基因上的 进化力量作用于其上的各种原材料， 更复杂的有机体。 因此，基于这一假设，性具有 被认为是一个重要的，几乎是必要的，组成部分， 进化过程然而，哈佛的马修·梅塞尔森博士 大学描述了一类动物，蛭总科，其中， 就目前所知，它没有性别遗传交换。但是， 正如他所指出的，性交换可能发生在罕见的情况下， 未知的情况下，需要更严格的测试来确认 一个成功进化的有机体 缺乏基因交换的机制。他建议使用 限制性片段长度多态性（RFLP）作为测试。 蛭总科的特定物种，被认为是二倍体， 选择作为试验微生物。分离的DNA将被片段化 限制性内切酶和杂合性的程度将是 测定潜在的假设是有性生物 纯合的染色体比无性的快得多 有机体这个项目可以在一年内完成 如果答案是几乎没有 在轮虫DNA中看到的杂合性，生物体可能有 一些类型性机制，因此，对于 进一步研究另一方面，如果答案是 在他们的DNA中有大量的杂合性， 深入了解我们对进化的理解， 问正确的问题 ** //