【摘要】 闽浙沿海是海洋生物物种分化与融合的重要“热点”区域，棘头梅童鱼（Collichthys lucidus）在该区域分化出南北两个谱系。为了查明棘头梅童鱼南北谱系交界区域的遗传结构及谱系分化的遗传基础，本研究基于全基因组测序分析了舟山、瑞安、宁德和厦门4个地理群体的遗传结构及分化模式。遗传多样性分析结果显示，棘头梅童鱼种群呈现显著的南北遗传分化，分界区域位于宁德至瑞安一带。成对群体遗传分化指数(F_ST)分析表明，远距离群体间分化高于近距离群体间，性染色体分化程度最高，除Chr.1外各染色体内部均表现出一端分化较高的特征。选择性扫描与功能富集结果显示，997个高分化基因显著富集于能量代谢、免疫防御、环境胁迫应对等环境适应相关条目上。本研究结果提示，地理隔离、环境选择，以及性染色体与着丝粒的协同作用可能共同驱动了棘头梅童鱼南北谱系的遗传分化。更多还原

【Abstract】 The Fujian-Zhejiang coastal region, located at the intersection of the East China Sea and South China Sea, represents a critical "hotspot" for marine biodiversity characterized by both species divergence and integration.Collichthys lucidus,a shallow-sea teleost species, has diverged into distinct northern and southern lineages in this region.This species serves as an ideal model for investigating the genetic mechanisms underpinning speciation and adaptive evolution.To resolve the genetic structure at the interface of these lineages and elucidate the drivers of genetic differentiation, the whole-genome sequencing data from four geographically distinct populations of C.lucidus（Zhoushan [ZS],Ruian [RA],Ningde [ND],and Xiamen [XM]） was analyzed.Findings confirmed significant genetic differentiation between the northern and southern populations, with the boundary localized between Ningde and Ruian, aligning with the historical Taiwan land bridge.Pairwise genetic differentiation(F_ST) analysis revealed that genetic divergence was greater between the geographically distant ZS-XM populations than between the closer ND-RA populations.Among the chromosomes analyzed, sex chromosomes（Chr.1,Chr.7,and Chr.8） exhibited the highest levels of genetic differentiation.Sliding window analysis further revealed a pattern of elevated differentiation at one terminal of most chromosomes, except Chr.1.Selective sweep and functional enrichment analyses identified 997 highly differentiated genes significantly enriched in pathways related to energy metabolism, immune defense, and environmental stress response.These results suggest that geographic isolation, environmental selection, and the coordinated effects of sex chromosome divergence and centromeric structure have collectively driven the genetic differentiation of C.lucidus’ northern and southern lineages.更多还原