斑马鱼发育早期CRH、UI和UII的表达及其对急性环境盐度、温度变化的响应

摘要： 促肾上腺皮质激素释放激素（CRH）、尾加压素I（UI）和尾加压素II（UII）广泛存在于所有脊椎动物中。为了深入探究CRH、UI和UII基因在硬骨鱼发育过程中的功能，本研究对斑马鱼发育早期CRH、UI和UII的表达及其对急性环境盐度、温度变化的响应进行研究。研究发现CRH、UI、UIIα和UIIβ mRNA从0hpf开始表达，而且CRH、UI、UIIα和UIIβ mRNA表达量随发育而改变，并分别在5dpf或6dpf达到最高水平。当2dpf、3dpf、4dpf和5dpf斑马鱼分别急性应激处理15min，盐度应激实验结果表明CRH、UI、UIIα和UIIβ mRNA表达量处理组与对照组相比均无显著性差异。温度应激实验结果表明，除3dpf外，急性温度变化会抑制CRH、UI、UIIα和UIIβ mRNA表达。
关键词： 促肾上腺皮质激素释放激素；尾加压素；斑马鱼；发育；盐度；温度

Lei Luo， Aqin Chen， Jianghong Xiong， Congcong Hu， Weiqun Lu^*

（  College of Fisheries and Life Sciences, Shanghai Ocean University；  ）

Abstract： Corticotropin releasing hormone (CRH), urotensin I (UI) and urotensin II (UII) are found throughout vertebrate species from fish to human. To further understand the role of CRH, UI and UII in teleosts during development, we investigated the expression pattern of CRH, UI, UIIα and UIIβ, and the response to acute salinity and temperature challenge during the early development of zebra?sh, Danio rerio. The results reveal that CRH, UI, UIIα and UIIβ mRNA are detected from 0hpf, and the relative expression levels alter along with development from 0hpf to 6dpf and reach the highest level at 6dpf except UIIα at 5dpf. After zebrafish at 2, 3, 4 and 5 dpf were exposed to an acute stress for 15min, no significant difference in expression levels of CRH, UI, UIIα and UIIβ mRNA was observed in response to acute osmotic (30ppt) stress compared with control, while cold stress (18℃) and hot stress (38℃) generally inhibited the mRNA levels of CRH, UI, UIIα and UIIβ at each time point apart from at 3dpf. These indicate that the contribution of CRH, UI, UIIα and UIIβ to stress response in zebrafish may be stressor-specific during early development. Overall, results from this study offer new insights into the developmental and temperature-specific function of CRH, UI, UIIα and UIIβ in zebrafish embryos and larvae.
Keywords： Corticotropin releasing hormone; Urotensin; Zebrafish; Development; Salinity; Temperature