cdh1基因在花鲈鳃盐度驯化中的表达特征分析  

Expression Analysis of cdh1 Gene in Spotted Sea Bass Gill During Salinity Acclimation

作　　者：李昀 陈志辉 王灵钰 齐鑫 李金库 陈通 温海深[1] Li Yun;Chen Zhihui;Wang Lingyu;Qi Xin;Li Jinku;Chen Tong;Wen Haishen(Key Laboratory of Mariculture(Ocean University of China),Ministry of Education,Qingdao 266003,China)

机构地区：[1]海水养殖教育部重点实验室(中国海洋大学),山东青岛266003

出　　处：《中国海洋大学学报（自然科学版）》2024年第10期190-200,共11页Periodical of Ocean University of China

基　　金：现代农业产业技术体系专项资金项目(CARS-47);国家自然科学基金项目(32072947)资助。

摘　　要：盐度是影响鱼类生理活动的重要环境因子。硬骨鱼类的鳃组织在应对环境盐度改变时会发生适应性变化,这种变化可能涉及细胞极性的改变。E-钙黏蛋白(E-cadherin,Cdh1)属于钙黏蛋白家族中的一员,在维持上皮细胞极性和细胞间连接方面起着关键作用。本研究通过组织学观察发现,花鲈(Lateolabrax maculatus)鳃组织在盐度驯化过程中发生了明显的形态重塑,且这种形态学变化是可逆的。为探究Cdh1在花鲈鳃形态重塑中的潜在作用,本研究对花鲈cdh1基因进行了克隆及序列分析,并对其在海淡水适应过程中的表达变化及分布特征进行了检测。实时荧光定量PCR结果表明,海水驯化过程中cdh1基因在鳃中的表达量呈逐渐下调的趋势,而在淡水驯化过程中cdh1基因的表达量呈逐渐上调的趋势,淡水环境下花鲈鳃组织中cdh1基因的表达量约为海水环境的2.88倍。原位杂交结果表明,在海水环境下,cdh1基因主要分布于鳃小片底部及相邻鳃小片之间的鳃丝上皮;在淡水环境下,cdh1基因均匀分布于整个鳃小片及相邻鳃小片之间的鳃丝上皮。免疫荧光结果表明,在海水驯化过程中,Cdh1蛋白在鳃小片上的分布逐渐减少直至信号集中在相邻鳃小片之间的鳃丝上皮,且Cdh1蛋白与钠钾ATP酶(Na,K-ATPase,NKA)不存在明显的共定位现象。研究结果表明,Cdh1介导的鳃上皮细胞极性改变与花鲈盐度驯化过程中鳃形态重塑密切相关,但与NKA无直接调控关系。本研究为揭示花鲈及其他广盐性鱼类在盐度驯化中的生理适应机制提供了重要依据。E-cadherin(Cdh1)belongs to the family of cadherin and plays a crucial role in maintaining epithelial cell polarity and intercellular adhesion.Histological observations showed that the gill tissue of spotted sea bass underwent a significant morphological remodeling during salinity domestication,and this morphological change was reversible.To explore the potential role of Cdh1 in gill morphological remodeling of spotted sea bass,its encoding gene,cdh1,was isolated and sequenced in this study with its expression during the process of seawater and freshwater acclimation analyzed.The results of real-time fluorescence quantitative PCR showed that the expression of cdh1 in gill was gradually down-regulated during seawater acclimation but gradually up-regulated during freshwater acclimation.The expression of cdh1 in the gill tissue of spotted sea bass in the freshwater environment was about 2.88 time higher than that in the seawater environment.The results of in situ hybridization indicated that Cdh1 was mainly distributed at the base of gill lamellae and the epithelium of the gill filaments between adjacent gill lamellae in the seawater environment.However,in the freshwater environment,it was uniformly distributed in the entire gill lamellae and the epithelium of the gill filaments between adjacent gill lamellae.The results of immunofluorescence showed that during the process of seawater domestication the distribution of Cdh1 in gill lamellae gradually decreased until the signal was concentrated on the epithelium of the gill filaments between adjacent gill lamellae,and there was no obvious co-localization of Cdh1 with the Na-and K-ATPase(NKA).These results suggested that Cdh1-mediated changes in gill epithelial cell polarity were closely related to gill morphological remodeling in spotted sea bass during salinity domestication,but not directly to NKA.Our findings provided important evidences for revealing the physiological acclimation mechanisms of spotted sea bass and other euryhaline fish species to salinity.

关 键 词：花鲈 盐度驯化 渗透调节 鳃重塑 CDH1 

分 类 号：S917.4[农业科学—水产科学]