Abstract Brazil has five climatically distinct regions, with an annual average temperature difference up to 14 ºC between the northern and southern extremes. Environmental variation of this magnitude can lead to new genetic patterns among farmed fish populations. Genetically differentiated populations of tambaqui (Colossoma macropomum Cuvier, 1818), an important freshwater fish for Brazilian continental aquaculture, may be associated with regional adaptation. In this study, we selected tambaquis raised in two thermally distinct regions, belonging to different latitudes, to test this hypothesis. De novo transcriptome analysis was performed to compare the significant differences of genes expressed in the liver of juvenile tambaqui from a northern population (Balbina) and a southeastern population (Brumado). In total, 2,410 genes were differentially expressed (1,196 in Balbina and 1,214 in Brumado). Many of the genes are involved in a multitude of biological functions such as biosynthetic processes, homeostasis, biorhythm, immunity, cell signaling, ribosome biogenesis, modification of proteins, intracellular transport, structure/cytoskeleton, and catalytic activity. Enrichment analysis based on biological networks showed a different protein interaction profile for each population, whose encoding genes may play potential functions in local thermal adaptation of fish to their respective farming environments.

中文翻译：

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本地鱼类 Colossoma macropomum 局部热适应的转录组证据（Cuvier，1818）


摘要 巴西有五个气候截然不同的地区，南北极端年平均温差高达 14 ℃。如此巨大的环境变化可能会导致养殖鱼类种群出现新的遗传模式。巴西大陆水产养殖的重要淡水鱼 tambaqui (Colossoma macropomum Cuvier, 1818) 的遗传分化种群可能与区域适应有关。在这项研究中，我们选择了在属于不同纬度的两个温度不同的地区饲养的 tambaquis 来检验这一假设。通过从头转录组分析来比较北部种群 (Balbina) 和东南种群 (Brumado) 幼年 tambaqui 肝脏中表达的基因的显着差异。总共有 2,410 个基因存在差异表达（Balbina 中 1,196 个，Brumado 中 1,214 个）。许多基因涉及多种生物功能，例如生物合成过程、稳态、生物节律、免疫、细胞信号传导、核糖体生物发生、蛋白质修饰、细胞内运输、结构/细胞骨架和催化活性。基于生物网络的富集分析显示，每个种群具有不同的蛋白质相互作用特征，其编码基因可能在鱼类对其各自养殖环境的局部热适应中发挥潜在功能。