斑节对虾CDC42基因的克隆及其在不同胁迫条件下的表达分析

Characterization and expression analysis of CDC42 in black tiger shrimp (Penaeus monodon) under different stress

细胞分裂周期蛋白42(CDC42)是一类广泛表达的小三磷酸鸟苷(GTP)酶,是Ras家族内Rho亚家族的成员之一,具有GTP酶活性。CDC42在细胞吞噬和炎症发生等先天免疫中发挥着不可替代的功能。该研究通过RACE技术克隆得到了斑节对虾(Penaeus monodon)细胞分裂周期蛋白42(Pm CDC42)基因c DNA全长。生物信息学分析结果表明Pm CDC42全长2 233 bp,包括59 bp的5'非编码区(UTR)、1 598 bp的3'UTR和576 bp的开放阅读框(ORF),编码191个氨基酸。通过实时定量PCR技术,研究了Pm CDC42在斑节对虾各组织的表达模式,并研究了其在不同p H、盐度、重金属镉(Cd)和哈维弧菌(Vibrio harveyi)胁迫下的表达情况。结果显示,Pm CDC42基因在各组织中均有表达,在血淋巴中的表达量最高。在p H和Cd胁迫下Pm CDC42表达量显著升高;在高盐胁迫下Pm CDC42表达量上调,低盐胁迫下Pm CDC42表达量变化不显著;在哈维弧菌的刺激下PmCDC42上调表达极显著。这表明Pm CDC42在斑节对虾先天免疫中起重要作用。

Cell Division Cycle 42 protein （CDC42） is a member of Rho family GTPases and plays an irreplaceable role in innate immunity such as phagocytosis and inflammation. In this study, the full-length eDNA ofPenaeus monodon CDC42 （PmCDC42） was cloned and characterized. The full-length PmCDC42 eDNA consisted of 2 233 bp with a 576 bp open reading frame, encoding 191 amino acids. The quantitative real-time PCR （qRT-PCR） analysis shows that PmCDC42 was ubiquitously expressed in all tested tissues and the highest expression level was obtained in the hemolymph. The expression pattern of PmCDC42 in the gill and hepatopancreas was detected under different conditions such as pH challenge, salinity stress, heavy metal cadmium exposure and Vibrio har-veyi challenge. The results show that the expression levels ofPmCDC42 mRNA in hepatopancreas and gill were up-regulated after different environmental stress, especially Kharveyi challenge. The results indicate that PmCDC42 may play an important role in im- munity of P.monodon.