Institut de Recherche pour le Développement, UMR DIAPC IRD/INRA/Université de Montpellier II/Sup-Agro, BP64501, 34394 Montpellier, Cedex 5, France.
Mol Ecol. 2011 Jan;20(1):80-91. doi: 10.1111/j.1365-294X.2010.04893.x. Epub 2010 Nov 3.
Identifying the molecular bases of adaptation is a key issue in evolutionary biology. Genome scan is an efficient approach for identifying important molecular variation involved in adaptation. Association mapping also offers an opportunity to gain insight into genotype-phenotype relationships. Using these two approaches coupled with environmental data should help to come up with a refined picture of the evolutionary process underlying adaptation. In this study, we first conducted a selection scan analysis on a transcription factor gene family. We focused on the MADS-box gene family, a gene family which plays a crucial role in vegetative and flower development. Twenty-one pearl millet populations were sampled along an environmental gradient in West Africa. We identified one gene, i.e. PgMADS11, using Bayesian analysis to detect selection signatures. Polymorphism at this gene was also associated with flowering time variation in an association mapping framework. Finally, we found that PgMADS11 allele frequencies were closely associated with annual rainfall. Overall, we determined an efficient way to detect functional polymorphisms associated with climate variation in non-model plants by combining genome scan and association mapping. These results should help monitor the impact of recent climatic changes on plant adaptation.
确定适应的分子基础是进化生物学中的一个关键问题。基因组扫描是识别与适应相关的重要分子变异的有效方法。关联作图也为深入了解基因型-表型关系提供了机会。结合这两种方法和环境数据，应该有助于更精细地了解适应背后的进化过程。在这项研究中，我们首先对一个转录因子基因家族进行了选择扫描分析。我们专注于 MADS 框基因家族，该基因家族在营养和花发育中起着至关重要的作用。我们沿着西非的环境梯度对 21 个珍珠粟种群进行了采样。我们使用贝叶斯分析来检测选择标记，确定了一个基因，即 PgMADS11。该基因的多态性也与关联作图框架中的开花时间变异有关。最后，我们发现 PgMADS11 等位基因频率与年降雨量密切相关。总的来说，我们通过结合基因组扫描和关联作图，确定了一种在非模式植物中检测与气候变异相关的功能多态性的有效方法。这些结果应该有助于监测最近气候变化对植物适应的影响。
