Polymorphic Duplications in the Evolution of New Genes in Drosophila

智力价值：基因复制是一种产生新基因的机制，对于与表型变异相关的新功能的进化来说，这是一种重要的基因新奇。基因复制是如何在物种种群中随着时间的推移而产生和丰度变化的，目前尚不清楚。这项研究旨在了解在种群中的一些个体中导致新基因功能的遗传机制和进化力量，而在另一些个体中则不是。本研究以果蝇为模型，采用一种综合的方法，在种群水平上解决与新基因功能进化相关的关键问题。首先，为了确定串联复制与分散复制的频率，将使用荧光标记和其他技术分析数百个已知存在于中高频的多态基因复制的染色体位置和序列。其次，为了测试与基因复制功能相关的进化约束的重要性，我们将检查和比较新基因复制在功能和非功能位点之间的序列变异和表达模式。第三，将通过比较物种内和物种间的差异来研究决定生存和自然选择的进化力量的影响。总而言之，这些实验的结果将为新基因功能的进化提供重要的见解。广泛的影响：该项目将生成一个特征良好的大型多态重复数据集，并将公开提供。该项目将与学生和公众的教育密切相关，并将促进芝加哥大学附近社区中代表性不足的族裔群体的教育。该项目将与芝加哥州立大学(CSU)合作，为CSU生物学专业的学生开启分子进化教学和研究培训的新方向，包括参加暑期研究、攻读基因组进化本科课程以及从事相关教育活动。此外，该项目还将培养研究生和博士后，从而为他们作为独立科学家的职业发展做出贡献。

Intellectual Merit: Gene duplication is a mechanism to generate new genes, an important genetic novelty for evolution of new functions associated with phenotypic variation. How a gene duplicate arises and changes in abundance over time in a species population is unclear. This research aims to understand the genetic mechanisms and evolutionary forces that lead to new gene functions in some individuals in a population and not in others. Using fruit flies as a model, this study applies an integrated approach to address key questions related to the evolution of new gene functions on a population level. First, to determine the frequency of tandem versus dispersed duplications, hundreds of polymorphic gene duplicates, known to be present at intermediate or high frequencies, will assayed for their chromosomal locations and sequences, using florescence labeling and other techniques. Second, to test the importance of evolutionary constraints related to functionality of the gene duplicates, sequence variation and expression patterns of the new gene duplicates will be examined and compared among functional and non-functional sites. Third, the influence of evolutionary forces governing survival and natural selection will be investigated by comparing within- and between-species variation. Together, the results of these experiments will provide important insights into the evolution of new gene functions.Broader Impacts: This project will generate a large well-characterized dataset of polymorphic duplicates that will be made publicly available. This project will be closely tied to the education of students and the public and will promote education of under-represented ethnic groups in the communities neighboring the University of Chicago. In collaboration with Chicago State University (CSU), this project will initiate a new direction of teaching and research training in molecular evolution for CSU biology students, including opportunities to participate in summer research, to take undergraduate courses about genome evolution, and to engage in related educational activities. In addition, this project will train graduate students and postdoctoral students, thus contributing to their career development as independent scientists.