Causes of Y-Chromosome Degeneration

Y染色体变性的原因

• 批准号: 0075295
• 负责人: Bryant McAllister
• 金额: $ 34.88万
• 依托单位: University of Texas at Arlington
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-08-01 至 2002-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0075295&HistoricalAwards=false
• 关键词: Causes; Chromosome; Degeneration

0075295McAllisterA morphologically and functionally distinct pair of sex chromosomes provides a basis for gender determination in many organisms. One chromosome (X) is shared between the two genders, and contains a normal set of functional genes; the other (Y) is restricted to one gender, and has few genes. These differences arise through a repeatable evolutionary process, because pairs of sex chromosomes have arisen multiple times from pairs of identical chromosomes (autosomes), a transition that has been demonstrated for the X-Y pair in humans. This project involves molecular and genetic analyses of Drosophila americana americana, a species with a chromosomal rearrangement that has recently transformed a pair of its autosomes into neo-sex chromosomes. The long-term objective of the study is to reveal the forces influencing loss of gene function on the male-limited neo-Y chromosome of D. a. americana. Studies will characterize the pattern of sequence variation in the region adjacent to the centromere of these neo-sex chromosomes, because this region is subjected to a gradient of restricted recombination. These data will lead to a better understanding of the relationship between recombination and the forces of mutation, selection and genetic drift.The study of Y chromosomes provides a model system for demonstrating the consequences of restricted recombination, which has implications for understanding factors influencing asexual reproduction and evolution within closely-linked regions of the genome.

一对在形态和功能上截然不同的性染色体为许多生物的性别决定提供了基础。一条染色体(X)在两性之间共享，包含一组正常的功能基因；另一条(Y)仅限于一种性别，基因很少。这些差异是通过一个可重复的进化过程产生的，因为性染色体对已经多次从一对相同的染色体(常染色体)中出现，这一转变已经在人类的X-Y染色体对中得到证明。这个项目涉及对美洲果蝇的分子和遗传分析，这是一个具有染色体重排的物种，最近将它的一对常染色体转化为新性染色体。这项研究的长期目标是揭示影响美洲斑潜蝇雄性限制的neo-Y染色体上基因功能丧失的因素。研究将描述这些新性别染色体着丝粒附近区域的序列变异模式，因为这一区域受到限制性重组的梯度影响。这些数据将有助于更好地理解重组与突变、选择和遗传漂移之间的关系。对Y染色体的研究为展示限制性重组的后果提供了一个模型系统，这对于理解基因组紧密相连区域内影响无性繁殖和进化的因素具有重要意义。