5个品系罗非鱼热休克蛋白Hsp70基因序列比对分析

Sequence Comparison of Heat Shock Protein 70 Gene from Five Strains of Tilapia

采用RT-PCR技术,对美国尼罗、埃及尼罗、美国奥利亚、中国奥利亚、奥尼杂交罗非鱼(埃及尼罗♀×美国奥利亚♂)5个品系罗非鱼热休克蛋白Hsp70基因进行扩增并克隆测序,最终获得5个品系罗非鱼Hsp70基因完整编码区(code sequences,CDS)cDNA序列,全长均为1923 bp,编码640个氨基酸,含有Hsp70家族3个签名序列IDLGTTYS、IFDLGGGTFD和VVLVGGSTRIP-KIQK,以及C末端保守序列EEVD,核定位信号标签KRKHKKDISQNKRALRR;Dank特征基序DLGTT-S-V;胞质Hsp70特征基序EEVD;靠近C末端的GGMP4肽序列;2个糖基化位点NKSI和NVSA。对5个品系罗非鱼Hsp70基因序列比较分析发现,它们之间共有12个核苷酸位点发生转换,但氨基酸序列完全一致。研究结果为深入研究不同品系罗非鱼的抗逆机理以及指导罗非鱼抗性育种奠定了可行性支撑基础。

The code sequences （CDS） of heat shock protein 70 gene were amplied and cloned from five strains of tilapias which are Oreochromis niloticus USA, Oreochromis niloticus Egypt, Oreochromis aurea USA, Oreochromis aurea CHINA and hybrid strain tilapia by RT-PCR. The sequence analysis show that the CDS of HspTO from five strains of tilapia are 1923bp,encoding 640 amino acid. The CDS have three signature sequences of heat shock protein 70 family （Hsp70 family） IDLGTITS, IFDLGGGTFD and VVLVGGSTRIPKIQK, the sequence of bipartite nuclear targeting KRKHKKDISQNKRALRR, the sequence of Dank subfamily DLGTT-S-V, the sequence of cytoplasm EEVD, four peptide sequence GGMP closely C-extreme,and two glycosylation site NKSI and NVSA. The result of sequence analysis showed that five strains of vtilapia have switched in 12 nucleotides and amino acids sequences had not changed. Cloning and comparison of lisp70 genes from different strains tilapia could be useful in the studies of anti-stress mechanism,tolerance-imprevement breeding and evolution for these species.