Hypoosmotic stress induced tissue-specific immune responses of yellowfin seabream (Acanthopagrus latus) revealed by transcriptomic analysis.
Salinity is a limiting factor for many marine organisms, including fishes. The shift in the ambient salinity can cause osmotic stress and arouse immune responses in fish. In this study, yellowfin seabream (Acanthopagrus latus), a euryhaline marine teleost, was used to investigate immune responses of different tissues (gill, liver, and muscle) under hypoosmotic stress. Comparative transcriptomic and physiological analyses of three tissues were conducted after fish exposed to the fresh water (FW, salinity = 0 ppt), low-saline water (LW, salinity = 3 ppt), and brackish water (BW, salinity = 6 ppt) for 8 days. The results showed that hypoosmotic stress dramatically altered the gene expression of three tissues in yellowfin seabream; The investigation of differentially expressed genes (DEGs) related to osmoregulation and immune response indicated that T cell-mediate immunity pathways were essential to tackle such stress. In terms of tissues, gill was found to be the most sensitive tissue under hypoosmotic stress by enhancing of Na+K+-ATPase activity and preventing the loss of Na+ and K+; Liver, on the other hand, was under the most sever oxidative stress indicated by the fluctuation of SOD, CAT activities and the MDA content; In contrast, muscle had the least osmoregulation and immune related response. We also identified several potential candidate genes, which may serve as gene indicators to identify the stressor. Overall, this study provides preliminary mechanistic insights into hypoosmotic stress adaption of aquatic organism.
['Lin|Genmei|G|', 'Zheng|Min|M|', 'Gao|Dong|D|', 'Li|Shizhu|S|', 'Fang|Wenyu|W|', 'Huang|Jing|J|', 'Xie|Jingui|J|', 'Liu|Jingxiong|J|', 'Liu|Yijing|Y|', 'Li|Zhaohong|Z|', 'Lu|Jianguo|J|']
D000064:Acclimatization D000818:Animals D005618:Fresh Water D020869:Gene Expression Profiling D005880:Gills D008099:Liver D009132:Muscles D064587:Osmoregulation D009997:Osmotic Pressure D054712:Salinity D021541:Sea Bream D017423:Sequence Analysis, RNA D013601:T-Lymphocytes
Hypoosmotic stress Immune responses Yellowfin seabream Osmoregulation RNA-Seq analysis