Comparative and Evolutionary Genomics of Self-Incompatibility in the Brassicaceae

十字花科自交不亲和性的比较和进化基因组学

• 批准号: 0077289
• 负责人: Mikhail Nasrallah
• 金额: $ 36万
• 依托单位: Cornell Univ - State: AWDS MADE PRIOR MAY 2010
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-08-15 至 2004-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0077289&HistoricalAwards=false
• 关键词: Comparative; Evolutionary; Genomics; Self; Incompatibility

0077289NasrallahPlants employ elaborate and sophisticated signaling systems that allow them to assess genetic relatedness among pollen donors. In many species of the mustard family (the Brassicaceae), a cell-cell signaling system based on the activity of receptor and ligand proteins displayed at the surfaces of the stigma epidermis and pollen grains respectively, results in the arrest of self-related pollen at the stigma surface. This self-incompatibility system, which is controlled by a large number of variants at the S locus, prevents self-fertilization and inbreeding, and promotes cross-pollination and outbreeding. The family Brassicaceae is comprised almost equally of self-fertilizing and outcrossing species, with self-incompatibility being the major determinant of this polymorphism in mating system control. As such, the presence or absence of a functional self-incompatibility system determines the patterns of genetic variation in populations and influences the rate and mode of evolutionary change in this family. The S loci of self-incompatible and self-fertile species belonging to diverged subgroupings of the Brassicaceae will be analyzed. In addition, transgenic experiments as well as interspecific hybrids and backcross populations between self-incompatible and self-fertile Arabidopsis species will be used to determine which genes are required to effect changes in mating system. These studies will be facilitated by advances in comparative genomics, namely the availability of the Arabidopsis nuclear genome sequence, the feasibility of constructing large-insert genomic libraries, and the rapid generation of molecular markers and maps. It is anticipated that the lineage of genes that play a major role in enforcing outcrossing will be traced, promising to shed light on the long-standing questions relating to the origin of SI in flowering plants and the genetic mechanisms underlying transitions between outcrossing and self-fertilizing mating systems.

0077289NASRALLAHPLANT采用精致而复杂的信号系统，使它们能够评估花粉供体之间的遗传相关性。 在芥末家族的许多物种中，基于受体和配体蛋白的活性在柱头表皮表面和花粉晶粒表面显示的细胞细胞信号系统，导致柱头表面上自相关花粉的停滞。 这种自我兼容的系统由S基因座的大量变体控制，可防止自我育种和近交，并促进跨花费和差异。胸前科的家族几乎包含了自我育种和杂交物种，自我兼容性是这种多态性在交配系统控制中的主要决定因素。因此，功能自我不相容性系统的存在或不存在决定了人群中遗传变异的模式，并影响了该家族中进化变化的速度和模式。将分析属于铜科分歧亚组的自我兼容和自我的物种的基因座。此外，将使用转基因实验以及种间杂种和自我兼容和自我的拟南芥物种之间的杂交种群来确定需要哪些基因来影响交配系统的变化。 这些研究将通过比较基因组学方面的进步，即拟南芥核基因组序列的可用性，构建大插入基因组文库的可行性以及分子标记和地图的快速产生。 可以预料，将追溯到​​在实施脱落方面发挥重要作用的基因谱系，这将被追溯，有望阐明与SI在开花植物中起源有关的长期问题，以及在杂交和自我繁殖系统之间进行过渡的遗传机制。