Changes in transcriptomic response to salinity stress induce the brackish water adaptation in a freshwater snail

Studying mechanisms of the establishment of a population in a novel environment allows us to examine the process of local adaptations and subsequent range expansion. In a river system, detecting genetic or phenotypic differences between a freshwater and brackish water population could contribute to our understanding of the initial process of brackish water adaptations. Here, we investigated behavioral and gene expression responses to the saltwater in a freshwater and brackish water population of the freshwater snail, Semisulcospira reiniana. Although the brackish water individuals exhibited significantly higher activity in saltwater than freshwater individuals in the first week, the activity of freshwater individuals increased in subsequent weeks, suggesting that their salinity tolerance was plastic rather than genetic. We found 476 and 1,002 differentially expressed genes across salinity conditions in the freshwater and brackish water populations, respectively. The major biological pro...探究物种在全新环境中建立种群的机制，有助于解析本地适应及后续分布范围扩张的过程。在河流生态系统中，检测淡水（freshwater）种群与半咸水（brackish water）种群间的遗传或表型差异，可助力我们理解半咸水适应的初始进程。本研究以淡水螺*Semisulcospira reiniana*的淡水种群与半咸水种群为研究对象，探究二者对盐水环境的行为与基因表达响应。尽管实验第一周时，半咸水种群个体在盐水环境中的活动能力显著高于淡水种群个体，但淡水种群个体的活动能力在后续几周中显著提升，这表明其盐度耐受能力具有可塑性，而非由遗传因素决定。本研究分别在淡水种群与半咸水种群中，鉴定得到476个和1002个不同盐度条件下的差异表达基因。其核心生物学pro...