温度和病原菌感染对大黄鱼热激蛋白90基因表达的影响

热激蛋白（heat shock protein,HSP）是进化上非常保守的蛋白质家族之一,普遍存在于各种生物体中,在多种生理活动中起到重要作用。该实验克隆了大黄鱼HSP90基因,并分析了温度和病原菌感染对其表达的影响。克隆到的大黄鱼HSP90序列长3 930 nt,含4个外显子和3个内含子,其中编码区2 178 nt,编码725个氨基酸。同源性分析发现,大黄鱼HSP90基因序列和其它鱼类的同源性在90%以上。在不同水温下,HSP90基因在不同组织中的表达量变化不同,心、肠和脑等组织在29 oC时表达量最高,而肌肉、脾和肝等组织在24 oC时表达量最高。用病原菌感染大黄鱼,感染48 h后,鳃、心、脾、肠、肾和脑组织HSP90的表达量明显上升;发病时（感染7天后）,受检的9种组织中HSP90的表达量都比未感染时明显增加。

Effect of Temperature and Pathogen on HSP90 Expression in Larimichthys crocea

Heat shock proteins（HSPs） existed in various organisms as a conserved protein family,and participated in many complex physiological processes.We cloned HSP90 gene and analysed the effect of temperature and pathogenic bacteria on its expression in Larimichthys crocea.The cloned HSP90 was 3 930 nt,including four exons and three introns.The open reading frame（ORF） was 2 178 nt encoding a polypeptide of 725 amino acids.Homology analysis showed that the deduced amino acid sequence of Larimichthys crocea HSP90 shared more than 90% identity with other fish.Under the different temperatures,HSP90 showed different expression patterns in the various tissues of Larimichthys crocea.HSP90 in heart,intestine and brain tissues had the strongest expression at 29 oC,whereas HSP90 in skeletal muscle,spleen and liver tissues exhibited the strongest expression at 24 oC.Larimichthys crocea was infected by intraperitoneal injection of pathogenic bacteria Pseudomonnas putida.HSP90 expression in gill,heart,spleen,intestine,kidney and brain tissues increased significantly after 48 h of injection.HSP90 expression in all examined nine tissues of the diseased fish was significantly higher than the control after 7 days of injection.