Abstract：
Freshwater salinization is an escalating global environmental issue that threatens freshwater biodiversity, including fish populations. This study aims to uncover the molecular basis of salinity physiological responses in a non-native minnow species (Phoxinus septimaniae x P. dragarum) exposed to saline effluents from potash mines in the Llobregat River, Barcelona, Spain. Employing high-throughput mRNA sequencing and differential gene expression analyses, brain, gills, and liver tissues collected from fish at two stations (upstream and downstream of saline effluent discharge) were examined. Salinization markedly influenced global gene expression profiles, with the brain exhibiting the most differentially expressed genes, emphasizing its unique sensitivity to salinity fluctuations. Pathway analyses revealed the expected enrichment of ion transport and osmoregulation pathways across all tissues. Furthermore, tissue-specific pathways associated with stress, reproduction, growth, immune responses, methylation, and neurological development were identified in the context of salinization. Rigorous validation of RNA-seq data through quantitative PCR (qPCR) underscored the robustness and consistency of our findings across platforms. This investigation unveils intricate molecular mechanisms steering salinity physiological response in non-native minnows confronting diverse environmental stressors. This comprehensive analysis sheds light on the underlying genetic and physiological mechanisms governing fish physiological response in salinity-stressed environments, offering essential knowledge for the conservation and management of freshwater ecosystems facing salinization.
摘要：
淡水盐碱化是一个不断升级的全球环境问题，威胁着淡水生物多样性，尤其是鱼类。这项研究旨在揭示暴露于Llobregat河钾矿的盐水废水中的非本地min鱼物种（PhoxinusseptimaniaexP.dragarum）的盐度生理反应的分子基础，巴塞罗那,西班牙。采用高通量mRNA测序和差异基因表达分析，大脑,ill,并检查了从两个站点（盐水排放的上游和下游）的鱼中收集的肝脏组织。盐碱化显著影响全球基因表达谱，大脑表现出最差异表达的基因，强调其对盐度波动的独特敏感性。通路分析揭示了离子转运和渗透调节通路在所有组织中的预期富集。此外，与应激相关的组织特异性通路，繁殖，增长,免疫反应，甲基化,在盐碱化的背景下确定了神经系统的发育。通过定量PCR（qPCR）对RNA-seq数据的严格验证强调了我们跨平台发现的稳健性和一致性。这项研究揭示了复杂的分子机制，指导面临各种环境压力的非本地min鱼的盐度生理反应。这一综合分析揭示了在盐度胁迫环境中控制鱼类生理反应的潜在遗传和生理机制，为面临盐碱化的淡水生态系统的保护和管理提供必要的知识。
