基于全基因组重测序解析中国西南喀斯特地区单枝竹属的物种形成与适应性进化

As a biodiversity hotspot with many endemic species, the karst region of southern China is an ideal natural laboratory for studying processes of speciation. However, the fragile ecosystem of this region is highly vulnerable to environmental changes with overharvesting of many rare plant resources. With four species and one variety, the bamboo genus Bonia is mainly distributed in the karst region of southern China and adaptive for limestone habit. This genus is economic and ecological important, but three of the four species are vulnerable and species boundaries have been in dispute. Clarifying species boundaries in this genus is vital for natural resource management of it, involving in understanding how new species form—the basic question in the field of evolutionary biology. With a sequenced nuclear genome as reference for this genus, this project plans to sample multiple individuals from each species of the genus for genome re-sequencing. We will assemble the complete plastid genome sequences and map the sequencing reads to the reference genome for variant calling, and construct phylogenetic trees based on plastid genome sequences and nuclear genome polymorphisms to clarify species boundaries in Bonia. Genomic islands of elevated divergence between lineages within Bonia will be determined and how they eventually lead to speciation will be explored. In the end, the underlying genetic mechanisms for adaptive evolution in karst region will be investigated through identifying genes in selective sweep regions of the nuclear genome. This project will provide insights into protecting and exploiting of these bamboos. In addition, we will also gain valuable insights at the genome-level into understanding of the evolution of species and origin of biodiversity in the karst region of southern China.

中国西南喀斯特地区生物多样性高、特有种多，是物种演化的天然实验场，然而该地区生态环境问题突出，大量珍稀植物资源被过度开发利用。我国单枝竹属Bonia包括共4种1变种竹类，主要分布于西南喀斯特地区，对石灰岩生境有极强的适应性，具有重要的经济和生态价值，其中3种为易危物种且物种界定不清。正确合理的物种划分是可持续利用植物资源的前提，涉及物种形成分化这一进化生物学研究领域的核心问题。在该属已有参考基因组基础上，本项目将对现有种在群体水平上取样多个个体，开展全基因组重测序，拼接叶绿体基因组和序列映射比对识别核基因组序列变异。构建系统树，确定该属种的基本进化单元；鉴定种群间高度分化变异的“基因组岛”区域，阐明其在物种形成中的作用；检测自然选择基因，揭示石灰岩生境适应性的遗传基础。该项目将为单枝竹属植物资源保护及发掘利用提供科学依据，在基因组层面上加深对西南喀斯特物种演化和该区域生物多样性起源的理解。

内容获取失败，请点击重试