Understanding the importance of convergent vs. lineage-specific molecular changes for convergent adaptations

相似性状在独立谱系中的趋同进化是最迷人的进化现象之一。以前的研究揭示了一些显著的例子，其中相似或有时相同的基因组变化是表型趋同的基础，这提出了一个基本问题：趋同与谱系特异性分子变化对表型趋同的贡献是什么？这个项目将解决这个问题，使用收敛适应富含糖的饮食在独立的食果和食蜜蝙蝠血统作为一个易于处理的模型。我们将使用一种综合方法，包括（i）生成高度连续和完整的战略选择蝙蝠的基因组以及与糖和胰岛素代谢相关的关键组织的基因表达数据，（ii）应用基因组方法在全基因组范围内筛选编码基因中的五种类型的突变特征，从而全面确定趋同和谱系-特定的基因变化，是相关的收敛糖饮食适应，及（iii）系统地确定收敛和特定的谱系变化，在frugi和nectarovorous蝙蝠基因表达。总之，这将揭示收敛以及谱系特异性变化的第一个全面图片，这些变化对于这些蝙蝠适应富含糖的饮食非常重要，这也可能揭示与人类代谢紊乱相关的有希望的目标。总的来说，该项目将提供新的见解，长期存在的问题，关于收敛与谱系特异性和基因序列与基因表达变化的表型收敛的重要性。

Convergent evolution of similar traits in independent lineages represents one of the most fascinating evolutionary phenomena. Previous studies revealed remarkable examples where similar or sometimes the same genomic changes underlie phenotypic convergence, which raises a fundamental question: What is the contribution of convergent vs. lineage-specific molecular changes to phenotypic convergence?This project will address this question using convergent adaptations to a sugar-rich diet in independent lineages of frugivorous and nectarivorous bats as a tractable model. We will use an integrative approach that comprises (i) generating highly-contiguous and complete genomes of strategically-selected bats together with gene expression data of key tissues relevant for sugar and insulin metabolism, (ii) applying genomic methods to screen genome-wide for five types of mutational signatures in coding genes and thus comprehensively determine convergent and lineage-specific gene changes that are relevant for convergent sugar diet adaptations, and (iii) systematically identifying convergent and lineage-specific shifts in gene expression in frugi- and nectarivorous bats. Together, this will reveal the first comprehensive picture of convergent as well as lineage-specific changes that are important for adaptations to sugar-rich diets in these bats, which may also uncover promising targets with relevance for human metabolic disorders. Overall, this project will provide novel insights into long-standing questions concerning the importance of convergent vs. lineage-specific and gene-sequence vs. gene-expression changes for phenotypic convergence.