Adaptation and speciation: The acquisition of new traits and adaptive potential via introgression. An Arabidopsis lyrata - arenosa introgression zone as example.

在这里，我们建议分析异交拟南芥物种的土壤适应的遗传基础，并研究这些物种在东北部石灰岩前阿尔卑斯山的自然杂交和渗入区。我们以前的特点渐渗从拟南芥arenosa（具有广泛的生态位，土壤条件）到石灰石适应拟南芥lyrata（在山区具有非常狭窄的生态位）。渗入的人口能够逃离这个狭窄的生态位和迁移到低地地区占主导地位的硅质岩向北进入多瑙河valley.Within这里提出的项目，大规模的平行DNA测序将用于确定基因组区域与土壤适应的二倍体种群的两个物种。在四倍体群体中，我们将分析拟南芥基因组的基因组贡献，这些基因组已经渗入到A。lyrata，并允许后者适应新的基板。具体来说，我们将问是否在二倍体种群中确定的适应性基因优先渗入四倍体杂交区。与此同时，将进行互惠培养实验，从不同的土壤适应人群的材料，以评估当地的适应程度，并在转录组水平的遗传差异，在不同的基板类型上进化的研究。

We here propose to analyze the genetic basis of edaphic adaptation in outcrossing Arabidopsis species and to study a natural hybridization and introgression zone of these species in the north-eastern Limestone Forealps. We have previously characterized introgression from Arabidopsis arenosa (with a broad ecological niche regarding edaphic conditions) into limestone adapted Arabidopsis lyrata (with a very narrow ecological niche in mountainous regions). The introgressed populations were capable to escape from this narrow ecological niche and migrated into lowland areas dominated by siliceous bedrocks northward into the Danube river valley.Within the here proposed project, massive parallel DNA sequencing will be used to identify genomic regions associated with edaphic adaptation in diploid populations of both species. In tetraploid populations we will then analyze the genomic contribution of the Arabidopsis arenosa genome that has introgressed into A. lyrata and allowed the latter to adapt to the new substrate. Specifically, we will ask whether adaptive genes identified in diploid populations have preferentially introgressed in the tetraploid hybridization zone. In parallel, reciprocal cultivation experiments with material from different edaphically adapted populations will be conducted to assess the extent of local adaptation and to study at the transcriptome level genetic differences that have evolved on different substrate types.