Simon F. S. Li Marine Science Laboratory, School of Life Sciences, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong, China.
Department of Biology, Hong Kong Baptist University, Kowloon Tong, Kowloon, Hong Kong, China.
Sci Rep. 2020 Dec 10;10(1):21771. doi: 10.1038/s41598-020-78351-w.
Osmoregulation and osmoconformation are two mechanisms through which aquatic animals adapt to salinity fluctuations. The euryhaline crab Scylla paramamosain, being both an osmoconformer and osmoregulator, is an excellent model organism to investigate salinity adaptation mechanisms in brachyurans. In the present study, we used transcriptomic and proteomic approaches to investigate the response of S. paramamosain to salinity stress. Crabs were transferred from a salinity of 25 ppt to salinities of 5 ppt or 33 ppt for 6 h and 10 days. Data from both approaches revealed that exposure to 5 ppt resulted in upregulation of ion transport and energy metabolism associated genes. Notably, acclimation to low salinity was associated with early changes in gene expression for signal transduction and stress response. In contrast, exposure to 33 ppt resulted in upregulation of genes related to amino acid metabolism, and amino acid transport genes were upregulated only at the early stage of acclimation to this salinity. Our study reveals contrasting mechanisms underlying osmoregulation and osmoconformation within the salinity range of 5-33 ppt in the mud crab, and provides novel candidate genes for osmotic signal transduction, thereby providing insights on understanding the salinity adaptation mechanisms of brachyuran crabs.
渗透调节和渗透适应是水生动物适应盐度波动的两种机制。广盐性螃蟹拟穴青蟹既是渗透适应者，也是渗透调节者，是研究短尾类动物盐度适应机制的理想模式生物。在本研究中，我们使用转录组学和蛋白质组学方法研究了拟穴青蟹对盐度胁迫的反应。将螃蟹从盐度 25 ppt 转移到 5 ppt 或 33 ppt 中 6 小时和 10 天。两种方法的数据均表明，暴露于 5 ppt 会导致与离子转运和能量代谢相关的基因上调。值得注意的是，适应低盐度与信号转导和应激反应的早期基因表达变化有关。相比之下，暴露于 33 ppt 会导致与氨基酸代谢相关的基因上调，并且仅在适应该盐度的早期阶段，氨基酸转运基因才上调。本研究揭示了在泥蟹的 5-33 ppt 盐度范围内，渗透调节和渗透适应的不同机制，并为渗透信号转导提供了新的候选基因，从而深入了解短尾类螃蟹的盐度适应机制。
