The Evolution of Molecular Parasites: The Importance of Geonomic Context

分子寄生虫的进化：地理环境的重要性

基本信息

批准号：
0630421
负责人：
Michael Hood
金额：
$ 7.82万
依托单位：
Amherst College
依托单位国家：
美国
项目类别：
Continuing Grant
财政年份：
2006
资助国家：
美国
起止时间：
2006-07-01 至 2009-01-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=0630421&HistoricalAwards=false
关键词：
Evolution Molecular Parasites Importance Geonomic

项目摘要

Molecular parasites, such as transposable elements, are segments of DNA that integrate into chromosomes and proliferate to become highly repetitive within the genome. This proliferation is often harmful to the genome and creates strong selection pressure to counter their activity. In the fungus Microbotryum violaceum a genomic defense mechanism ("repeat-induced point mutations") acts to change the DNA sequence of molecular parasites thus destroying their ability to proliferate. Empirical and theoretical studies will investigate the evolution of molecular parasites as they appear to engage in an arms race with the host genome in order to elude its defensive mechanisms. Molecular parasites are highly influential components of the genomes of nearly all organisms, with effects upon such fundamental traits as genome size, mutation rates, DNA structure, and mating systems. The activity of molecular parasites has also been implicated in many human-inherited diseases and chromosome rearrangements. Therefore, investigation into which factors limit the evolution of molecular parasites will advance our understanding of genome structure and of particular threats to genetic stability. This research also has broad theoretical implications because it addresses the unique nature of DNA-based parasitism that allows for co-evolution between the molecular parasites and the genomes they inhabit.

分子寄生虫（例如可转座元素）是DNA的段，它们整合到染色体中并增殖以在基因组中变得高度重复。这种扩散通常对基因组有害，并产生强大的选择压力以应对其活性。在真菌微生物中，基因组防御机制（“重复诱导的点突变”）作用于改变分子寄生虫的DNA序列，从而破坏了它们增殖的能力。经验和理论研究将研究分子寄生虫的演变，因为它们似乎与宿主基因组一起参加了武器竞赛，以避免其防御机制。分子寄生虫是几乎所有生物体的基因组的高度影响成分，对基因组大小，突变率，DNA结构和交配系统等基本特征的影响。分子寄生虫的活性也与许多人类结构疾病和染色体重排有关。因此，研究哪些因素限制分子寄生虫的演变将提高我们对基因组结构的理解以及对遗传稳定性的特殊威胁。这项研究也具有广泛的理论含义，因为它解决了基于DNA的寄生虫的独特性质，该寄生虫允许分子寄生虫与它们所居住的基因组之间的共同发展。