DISSERTATION RESEARCH: Reproductive Incompatibility by Compensatory Mutations.

论文研究：补偿性突变导致的生殖不相容。

• 批准号: 0308782
• 负责人: Michael Lynch
• 金额: $ 1.2万
• 依托单位: Indiana University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-08-15 至 2005-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0308782&HistoricalAwards=false
• 关键词: DISSERTATION; RESEARCH; Reproductive; Incompatibility; Compensatory

The maintenance of populations at small sizes can lead to the accumulation of deleterious mutations that undermine the fitness of individuals. However, subsequent return to large population size can result in the fixation of beneficial mutations at other loci that compensate for these negative effects. Such an advantageous association can be disrupted during outcrossing, thereby leading to a fitness decline in hybrids and representing a first step in the formation of new species. This research represents the first experimental test of the role of compensatory mutations in the evolution of reproductive incompatibility. Using the nematode model system C. elegans, this project attempts to: 1) subject multiple lines to a regime of deleterious mutation accumulation by maintenance at small population sizes with a knockout of a key DNA mismatch repair gene; 2) initiate fitness recovery in mutationally degraded lines via the accumulation of compensatory mutations under large population sizes, thereby creating line-specific coadapted gene complexes and 3) test for diminished fitness in hybrid progeny. This study will test the role of inter-locus gene interactions in the evolution of reproductive incompatibility, evaluate the validity of a key model of speciation, and have implications for conservation management practices.

维持小规模种群可能会导致有害突变的积累，从而破坏个体的健康。然而，随后恢复到大种群规模可能会导致有益突变固定在其他基因座上，以补偿这些负面影响。这种有利的关联可能在异型杂交过程中被破坏，从而导致杂种的适应性下降，并代表新物种形成的第一步。这项研究首次对补偿性突变在生殖不相容进化中的作用进行了实验测试。使用线虫模型系统秀丽隐杆线虫，该项目试图：1）通过敲除关键的 DNA 错配修复基因，维持小群体规模，使多个品系遭受有害突变积累的机制； 2) 通过在大群体规模下积累补偿性突变，启动突变退化品系的适应性恢复，从而创建品系特异性的共适应基因复合物；3) 测试杂交后代中适应性下降的情况。 这项研究将测试基因座间基因相互作用在生殖不相容性进化中的作用，评估物种形成关键模型的有效性，并对保护管理实践产生影响。