岛屿特征对两栖动物免疫基因进化影响的研究

The identification of factors that influence the genetic diversity and differentiation at adaptive loci provides important insights into the evolutionary process, and is also crucial for molecular ecology, evolutionary biology, and conservation biology. The major histocompatibility complex (MHC) is one of the most polymorphic regions in the vertebrate genome, playing a critical role in pathogen detection, recognizing and presenting foreign antigens and triggering the adaptive immune response. However, few studies have identified the unique contribution of environmental factors to MHC diversity in insular populations. This project will obtain sequence information (including viruses and MHC gene) by using high throughput sequencing. This project will use hierarchical partitioning (HP) analysis to quantify the unique contribution of island features to MHC diversity. This project will directly compare diversity between MHC and microsatellites gene using background variations in mainland populations as the reference. The project will also explore that diversifying selection is the main selective force acting on MHC gene in Zhoushan Archipelago.

鉴定影响瓶颈种群中功能基因位点遗传多样性丧失的因素，是分子生态学、进化生物学和保护生物学的重要研究内容。Major histocompatibility complex (MHC)基因具有免疫认知功能，并且具有高度多态性的特点，是当代各学科研究的热点基因。然而，关于MHC基因在瓶颈种群中如何进化，受哪些环境因素影响，以及这些环境影响因子对MHC基因进化的独立贡献如何，还没有系统完整的研究。本项目利用特殊的陆桥岛环境、微生物宏基因组技术和高通量测序技术获得数据，构建模型分别量化环境选择压力和遗传漂变（种群大小和世代数）对黑斑侧褶蛙(Pelophylax nigromaculatus) MHC基因进化的影响。综合前期中性位点的研究，进一步比较研究中性基因和功能基因在瓶颈种群中遗传多样性损失速率的快慢。通过控制中性位点遗传分化，探讨多元化选择对舟山群岛黑斑侧褶蛙MHC基因进化所起到的重要作用。

鉴定影响瓶颈种群中功能基因位点遗传多样性丧失的因素，是分子生态学、进化生物学和保护生物学的重要研究内容。Major histocompatibility complex (MHC)基因具有免疫认知功能，并且具有高度多态性的特点，是当代各学科研究的热点基因。本项目利用特殊的陆桥岛环境、微生物宏基因组技术和高通量测序技术获得数据，构建模型分别量化环境选择压力和遗传漂变（种群大小和世代数）对黑斑侧褶蛙(Pelophylax nigromaculatus) MHC基因进化的影响。我们发现MHC遗传多样性受种群大小影响最大，岛屿面积其次，岛屿形成时间最小。综合前期中性位点的研究，我们发现MHC基因遗传多样性的损失速率要低于中性基因。通过控制中性位点遗传分化，我们发现多元化选择对舟山群岛黑斑侧褶蛙MHC基因进化所起到了重要作用。