Detecting adaptive divergence in a widespread aquatic plant using genetic markers under selection and genome scans

使用选择和基因组扫描下的遗传标记检测广泛分布的水生植物的适应性分歧

• 批准号: 27031200
• 负责人: Professor Dr. Thorsten Reusch, Ph.D.
• 金额: --
• 依托单位: Forschungsbereich 3: Marine Ökologie
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2006
• 资助国家: 德国
• 起止时间: 2005-12-31 至 2011-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/27031200?language=en
• 关键词: Detecting; adaptive; divergence; widespread; aquatic

The goal of this project is to identify genes under positive divergent selection as one strategy for studying molecular adaptation under natural conditions. The plant model is eelgrass (Zostera marina), a widespread marine angiosperm that has recently become a population genetic model species of coastal environments. Based on existing EST (expressed sequence tag)-libraries, I will establish gene-linked markers (SNPs ¿ single nucleotide polymorphisms; microsatellites) in order to compare genetic differentiation among replicated pairs of populations in contrasting habitat types, corresponding to divergent selection. A genome scan approach will identify outlier loci by formally rejecting neutral population genetic models that incorporate realistic scenarios of gene flow, mutation rates and drift. The advantages of gene-linked markers over anonymous ones for estimating selectively relevant genetic diversity will be assessed in re-examining established heterozygote-fitness correlations. Genes under divergent selection based on genome scans will be further characterized and sequenced in order to find additional evidence for molecular adaptation at the DNA sequence level.

本项目的目的是鉴定正分化选择下的基因，作为研究自然条件下分子适应的一种策略。植物模式是大叶藻（Zostera marina），一种广泛分布的海洋被子植物，最近成为沿海环境的种群遗传模式物种。基于现有的EST（表达序列标签）文库，我将建立基因连锁标记（snp，单核苷酸多态性，微卫星），以便比较不同栖息地类型中复制对种群之间的遗传分化，对应于分化选择。基因组扫描方法将通过正式拒绝包含基因流动，突变率和漂移的现实情景的中性群体遗传模型来识别异常位点。基因连锁标记相对于匿名标记在评估选择性相关遗传多样性方面的优势，将通过重新检查已建立的杂合子适应度相关性来评估。基于基因组扫描的不同选择下的基因将进一步表征和测序，以便在DNA序列水平上寻找分子适应的额外证据。