GENETICS OF THE SELF-INCOMPATIBILITY (S-) LOCI

自交不亲和性 (S-) 位点的遗传学

• 批准号: 7719955
• 负责人: NAOKI TAKEBAYASHI
• 金额: $ 19.32万
• 依托单位: UNIVERSITY OF ALASKA FAIRBANKS
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-05-01 至 2009-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7719955
• 关键词: Address; Age; Alleles; Angiosperms; Brassicaceae; Communities; Computer Retrieval of Information on Scientific Projects Database; Data; Disease Resistance; Endoribonucleases; Evolution; Funding; Genes; Genetic; Genetic Polymorphism; Genetic Variation; Genotype; Goals; Grant; Human; Inbreeding; Institution; Knowledge; Modeling; Molecular; Nature; Numbers; Pancreatic ribonuclease; Papaver; Papaveraceae; Partner in relationship; Pattern; Plants; Pollen; Population; Process; Recording of previous events; Research; Research Personnel; Resources; Ribonucleases; Rosacea; Rosaceae; Scrophulariaceae; Self-Fertilizations; Sex Chromosomes; Side; Solanaceae; Source; Specificity; Students; System; Testing; Time; United States National Institutes of Health; ZAP-70 Gene; abstracting; base; computerized tools; experience; prevent; programs

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Currently, we are focusing on empirical side of self-incompatibility (S-) locus evolution. Self-incompatibility (SI) is a genetic mechanism to prevent inbreeding in plants. S-locus determines mating specificities (who can mate with whom), and analogous to sex chromosome in human. Additionally, S-locus experiences evolutionary forces similar to MHC loci because both SI MHC are mechanisms of self-/nonself-recognition. 2007-2008 With Mike Hickerson(CUNY Queens) : We aim to develop statistically rigorous computational tools to test phylogeographic hypotheses. Abstract: Fundamental questions about the determinants and dynamics of community assembly and the historically geographic nature of species diversity have been vexing the scientific community since before the times of Darwin. By estimating the geographic history of all species within a community, phylogeographic data may be able to address the controversial and unresolved hypotheses explaining the forces determining community assembly. Toward this goal, we are expanding hierarchical approximate Bayesian computation (hABC) models used in msBayes (a program which we released to test phylogeographic hypotheses such as simultaneous divergence of species pairs). 2007-2008: With graduate student: Takashi Miyake, We are characterizing the diversification pattern of self-incompatibility locus at the molecular level in poppy. Abstract: Self-incompatibility is a genetic system of self-recognition that allows flowering plants to avoid self-fertilization. Self-incompatible plants are typically fertilized only by pollen with a different mating specificity (S-locus genotype), producing strong diversifying selection. Dozens of alleles may be maintained in a single population, and polymorphism within species is ancient. However, empirical knowledge of the evolutionary dynamics of self-incompatibility loci presently comes from just two systems, the RNase-based system in Solanaceae, Scrophulariaceae and Rosaceae, and the SRK system of Brassicaceae. We propose to characterize self-incompatibility in the Papaveraceae, which has a different molecular mechanism of self-incompatibility, by examining sequence diversity of S-alleles in five species of Papaveraceae from four genera. Diversifying selection creates and maintains extreme levels of genetic variation in terms of the numbers of alleles, their sequence divergence, and the age of polymorphism. Diversifying selection underlies many important processes in nature including self-recognition systems and disease resistance loci such as the human MHC loci. This study will reconstruct the history of diversification of a self-recognition gene that has not been previously examined, and will provide the first comparison of self-incompatibility loci in which the selective process is the same (gametophytic), but the molecular basis differs.

该子项目是利用该技术的众多研究子项目之一 资源由 NIH/NCRR 资助的中心拨款提供。子项目及 研究者 (PI) 可能已从 NIH 的另一个来源获得主要资金， 因此可以在其他 CRISP 条目中表示。列出的机构是 中心，不一定是研究者的机构。 目前，我们关注的是自交不亲和的实证方面 (S-) 基因座进化。 自交不亲和性（SI）是一种防止植物近交的遗传机制。 S基因座决定交配特异性（谁可以与谁交配），类似于人类的性染色体。 此外，S 基因座经历与 MHC 基因座类似的进化力量，因为 SI MHC 都是自我/非自我识别的机制。 2007-2008 与 Mike Hickerson（纽约市立大学皇后区）合作：我们的目标是开发统计上严格的计算工具来测试系统发育地理学假设。 摘要：自达尔文时代之前，关于群落聚集的决定因素和动态以及物种多样性的历史地理性质的基本问题一直困扰着科学界。 通过估计群落内所有物种的地理历史，系统发育地理学数据可能能够解决有争议和尚未解决的假设，这些假设解释了决定群落组装的力量。 为了实现这一目标，我们正在扩展 msBayes（我们发布的一个程序，用于测试系统发育地理学假设，例如物种对的同时分歧）中使用的分层近似贝叶斯计算 (hABC) 模型。 2007-2008：与研究生：Takashi Miyake一起，我们在分子水平上表征了罂粟自交不亲和基因座的多样化模式。 摘要：自交不亲和性是一种自我识别的遗传系统，可以使开花植物避免自体受精。 自交不亲和植物通常仅通过具有不同交配特异性（S位点基因型）的花粉受精，产生强烈的多样化选择。单个种群中可能维持数十个等位基因，物种内的多态性由来已久。 然而，自交不亲和基因座进化动力学的经验知识目前仅来自两个系统，即茄科、玄参科和蔷薇科的基于RNase的系统，以及十字花科的SRK系统。我们建议通过检查来自四个属的五个物种的 S 等位基因的序列多样性来表征罂粟科的自交不亲和性，其具有不同的自交不亲和分子机制。 多样化选择在等位基因数量、序列差异和多态性年龄方面创造并维持极端水平的遗传变异。多样化选择是自然界许多重要过程的基础，包括自我识别系统和抗病基因座，例如人类 MHC 基因座。这项研究将重建之前未曾研究过的自我识别基因的多样化历史，并将提供自交不亲和基因座的首次比较，其中选择过程相同（配子体），但分子基础不同。