Divergence of underlying mechanisms in response to alkalinity conditions between two crucian carp (Carassius auratus) populations

作者：Kexin Zhang, Jing Huang, Guo Hu, Cuiyun Lu, Limin Zhang, Tianqi Liu, Zhipeng Sun, Rongbin Na, Yuting Zou, Xianhu Zheng, Yu‐Mei Chang · 发表于：Ecotoxicology and Environmental Safety · 年份：2025 · DOI：10.1016/j.ecoenv.2025.119164 · 被引用次数：5 · 研究领域：Physiological and biochemical adaptations、Fish Ecology and Management Studies、Aquaculture Nutrition and Growth

Climate change and anthropogenic activities are accelerating the global expansion of saline-alkaline water. High-alkalinity is a dominant stressor threatening aquatic organism survival and reproduction. Understanding the mechanism underlying alkalinity tolerance is essential for assessing the adaptive potential and guiding molecular breeding for saline alkaline aquaculture. Here, we investigated the divergence of physiological and molecular responses to different alkalinity conditions between freshwater (PX) and alkaline water (DL) populations of Carassius auratus , a species exhibiting high-alkalinity plasticity. The PX and DL populations showed significant alkalinity adaptive divergence: both showed high adaptability to low- and moderate-alkalinity, but the DL population showed superior tolerance to high-alkalinity. Alkalinity-responsive and population-divergent genes and metabolites were enriched in energy and ammonia metabolism-related shared pathways, including amino sugar and nucleotide sugar metabolism, lipid metabolism, nitrogen metabolism and alanine, aspartate and glutamate metabolism. In contrast to the PX population, the urea cycle and transamination were enhanced in the DL population, whereas amino sugar and nucleotide sugar metabolism, amino acid oxidation and glycolysis were suppressed under alkalinity stress. Carbamoyl-phosphate synthase upregulation and glutaminase downregulation indicated enhanced ammonia detoxification for alkalinity adaptation in the DL po...