Abstract:

According to the Hyriopsis cumingii (H. cumingii) expressed sequence tags (EST) obtained by constructing subtractive hybridization cDNA library, the gene full-length cDNA sequence of Rab3 from H. cumingii was cloned by RACE-PCR technique(GenBank accession number: HQ190954).. The results showed that the length of Rab3 gene cDNA sequence was 1 707bp, containing a complete open reading frame 666bp, encoding a peptide of 221 amino acid residues(aa), flanked by a 158 bp of 5’untranslated region(UTR)and a 883 bp of 3’-UTR. The deduced molecular weight of Rab3 is about 24.92KDa. Amino acid sequence analysis shows that, Suberites domuncula Rab-3like and Hyriopsis cumingii Rab3 is the highest, about 64%, evolutionary tree conclusion is the same with that result. The Rab3 positives was therefore designaged HcRab3(GenBank accession number: HQ190954).The result of analysis with NCBI Blastp , which beween HcRab3 and SdRab3, which shares a positives of 64%.Induced with 30℃, 5h, 1mM IPTG, the HcRab3 was expressed at high levels, electrophoretic analysis by SDS-PAGE revealed that 26kD Protein expression band was obtained. After Western-blot in healthy and deseased Hyriopsis cumingii lever protein, the expression ratio of Rab3 protein and beta actin is 0.438 and 0.580. Rab3 can regulating exocytosis of body neutrophils, it is preliminarily presumed that the HcRab3 maybe related to Hyriopsis cumingii plague.