Evolution of Meiotic Mechanisms in Divergent Cytological Environments

不同细胞学环境中减数分裂机制的进化

基本信息

批准号：
8457163
负责人：
Kevin Wright
金额：
$ 5.22万
依托单位：
HARVARD UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2013
资助国家：
美国
起止时间：
2013-02-01 至 2016-01-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8457163
关键词：
Address Affect Alleles Animal Model Arabidopsis Backcrossings Biological Process Cataloging Catalogs Cells Chromatin Structure Chromosome Mapping Chromosome Pairing Chromosome Segregation Chromosomes Data Development Diploidy Disease Down Syndrome Elements Ensure Environment Event Evolution Fertility Fluorescent in Situ Hybridization Frequencies Generations Genes Genetic Crossing Over Genetic Transformation Genome Genomics Genotype Germ Cells Homologous Gene Infertility Investigation Laboratories Laboratory Research Lead Maps Measures Meiosis Molecular Molecular Genetics Molecular Profiling Mutation Nature Optic Chiasm Organism Polyploidy Process Prophase Proteins Recurrence Ribosomal DNA Spontaneous abortion Sterility System Systems Development Testing Transgenic Organisms Variant base experience genome sequencing interest novel pressure protein function public health relevance research study response segregation structural genomics

项目摘要

DESCRIPTION (provided by applicant): Meiosis is a fundamental process for all sexual reproducing organisms. Problems in this process can lead to chromosome mis-segregation, which can result in sterility, lethality, and diseases such as Down's syndrome. Many proteins and elements of meiosis are evolutionarily conserved, there is species level variation in the precise meiotic mechanisms, but there is remarkably little data on how these different mechanisms or the associated proteins have evolved. I propose to address the question of how a novel meiotic process and associated proteins evolve by studying cytological and functional molecular genetic differences between closely related diploid and autotetraploid Arabidopsis arenosa. Polyploidy is an ideal system to study this question, because there is strong selective pressure on the meiosis machinery to ensure proper pairing, crossing- over, and segregation in an environment with double the number of homologous chromosomes. To catalogue the differences between these environments, I propose to conduct a detailed cytological investigation of diploid, natural autotetraploid, and synthetic tetraploid lines. I will also investigate the function of meiosis related proteins with strong signatures of selection in the tetraploid lineage through transgenic analysis. In a complimentary experiment, I will conduct an artificial selection experiment on gamete viability in the synthetic autotetraploid and genetically map loci that ensure proper meiosis in the tetraploid.

描述（由申请人提供）：减数分裂是所有有性生殖生物体的基本过程。这一过程中的问题可能导致染色体错误分离，从而导致不育、死亡和唐氏综合症等疾病。减数分裂的许多蛋白质和元件在进化上是保守的，精确的减数分裂机制存在物种水平的差异，但关于这些不同机制或相关蛋白质如何进化的数据却非常少。我建议通过研究密切相关的二倍体和同源四倍体拟南芥之间的细胞学和功能分子遗传差异来解决新的减数分裂过程和相关蛋白质如何进化的问题。多倍体是研究这个问题的理想系统，因为减数分裂机制存在强大的选择压力，以确保在同源染色体数量加倍的环境中正确配对、交叉和分离。为了对这些环境之间的差异进行分类，我建议对二倍体、天然同源四倍体和合成四倍体系进行详细的细胞学研究。我还将通过转基因分析研究四倍体谱系中具有强烈选择特征的减数分裂相关蛋白的功能。在免费实验中，我将对合成同源四倍体的配子活力进行人工选择实验，并进行遗传性选择实验。绘制确保四倍体适当减数分裂的基因座。