杂交黄颡鱼hsp70基因核心序列的克隆、表达及其在高温应激下的组织表达

Cloning, expression of hsp70 core cDNA and the effects of heat stress on its tissue expression in Pelteobagrus fulvidraco ♀×P. vachelli ♂

关键词:  高温应激  黄颡鱼  hsp70基因  组织表达

Key words:  Heat stress  Pelteobagrus fulvidraco  hsp70 gene  Tissue expression

摘要:

热休克蛋白70(Heat Shock Protein 70, HSP70)与生物体抗逆抗胁迫能力密切相关，其在生物体内发挥着十分重要的作用。本研究以杂交黄颡鱼(黄颡鱼Pelteobagrus fulvidraco ♀ ×瓦氏黄颡鱼P. vachelli ♂)为对象，得到735 bp的hsp70 cDNA核心序列，并进行了生物信息学分析；运用实时荧光定量PCR方法检测hsp70基因mRNA在不同组织中的相对表达量。结果显示，hsp70基因在肝脏、鳃、脑、肌肉4个组织中均有表达，其中，正常条件下，在肝脏的表达量显著高于在脑、鳃和肌肉的表达量(P<0.05)；在20℃(常温组)、25℃、28℃和31℃ 4个温度条件下，杂交黄颡鱼hsp70基因在肝脏、鳃、脑和肌肉组织中的表达量总体上随温度升高呈上升趋势，其中，28℃和31℃下，hsp70基因在鳃中的表达量显著高于其他组织(P<0.05)，表明鳃为杂交黄颡鱼温度应激的敏感组织，可能是作为呼吸代谢重要器官的鳃在温度急剧变化情况下的一种机体保护策略。

Abstract:

Heat shock protein 70 (HSP70) is closely related to the stress resistance and anti-stress ability of organisms, where it plays a crucial role. In the present study, a 735 bp core cDNA sequence of the hsp70 gene isolated from the liver tissue of Pelteobagrus fulvidraco ♀×P. vachelli ♂ was amplified using reverse transcription polymerase chain reaction (RT-PCR), and the bioinformatics was analyzed. The relative mRNA expression of the hsp70 gene in different tissues was tested using quantitative real-time PCR (qPCR), which revealed that hsp70 mRNA was found in all tested tissues, including liver, gill, brain, and muscle, and hsp70 mRNA expression levels in liver tissue were significantly different from that in brain, gill, and muscle tissue (P<0.05). At 20℃ (control), 25℃, 28℃, and 31℃, the hsp70 gene expression in liver, gill, brain, muscle tissue generally increased with increasing temperature. The hsp70 gene expression level in gill tissue at 28℃ and 31℃ was significantly higher than that in other tissues (P<0.05), which indicated that gill tissue was sensitive to heat stress in the hybrid. It was suggested that this may be an organism protection strategy for gill tissue, which is important for respiratory metabolism under extreme changes in temperature.