Department of Forest and Conservation Sciences, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada; Pacific Biological Station, Fisheries and Oceans Canada, Nanaimo, British Columbia V9T 6N7, Canada.
Pacific Biological Station, Fisheries and Oceans Canada, Nanaimo, British Columbia V9T 6N7, Canada.
Comp Biochem Physiol Part D Genomics Proteomics. 2019 Mar;29:32-42. doi: 10.1016/j.cbd.2018.10.002. Epub 2018 Oct 18.
There is a paucity of information on the physiological changes that occur over the course of salmon early marine migration. Here we aim to provide insight on juvenile Coho salmon (Oncorhynchus kisutch) physiology using the changes in gene expression (cGRASP 44K microarray) of four tissues (brain, gill, muscle, and liver) across the parr to smolt transition in freshwater and through the first eight months of ocean residence. We also examined transcriptome changes with body size as a covariate. The strongest shift in the transcriptome for brain, gill, and muscle occurred between summer and fall in the ocean, representing physiological changes that we speculate may be associated with migration preparation to feeding areas. Metabolic processes in the liver were positively associated with body length, generally consistent with enhanced feeding opportunities. However, a notable exception to this metabolic pattern was for spring post-smolts sampled soon after entry into the ocean, which showed a pattern of gene expression more likely associated with depressed feeding or recent fasting. Overall, this study has revealed life stages that may be the most critical developmentally (fall post-smolt) and for survival (spring post-smolt) in the early marine environment. These life stages may warrant further investigation.
有关鲑鱼早期海洋洄游过程中发生的生理变化的信息很少。在这里，我们旨在通过对 4 种组织（大脑、鳃、肌肉和肝脏）在淡水的幼鲑鱼（Oncorhynchus kisutch）从幼鱼到变态过渡过程中的基因表达变化（cGRASP 44K 微阵列），以及在海洋中生活的前 8 个月，来了解其生理学变化。我们还研究了转录组变化与体型作为协变量的关系。大脑、鳃和肌肉的转录组在海洋中的夏季和秋季之间发生了最强的变化，我们推测这可能与向摄食区迁移的生理准备有关。肝脏中的代谢过程与体长呈正相关，通常与增强的摄食机会一致。然而，一个值得注意的例外是在进入海洋后不久被采样的春季变态后幼鱼，其基因表达模式更可能与摄食减少或最近的禁食有关。总的来说，这项研究揭示了在早期海洋环境中可能是发育（秋季变态后）和生存（春季变态后）最关键的生命阶段。这些生命阶段可能需要进一步研究。
