Molecular characteristics of three thymosin-repeat proteins from Marsupenaeus japonicus and their responses to WSSV infection
Published:2016-10-11 03:24:55    Text Size:【BIG】【MEDIUM】【SMALL
Summary:β-thymosins, a family of highly conserved peptides, played a vital role in wound-healing, angiogenesis, antimicrobial process and antiviral immunity. Three novel β-thymosins, named mjthm4, mjthm3 and mjthm2, were cloned from Marsupenaeus japonicus using expressed sequence tags (EST) from suppression subtractive hybridization. The mjthm4, mjthm3 and mjthm2 cDNA possessed open reading frames that encoded 166, 128 and 90 amino acid residues polypeptides and contained four, three and two β-thymosin actin binding modules, respectively. Blast analysis demonstrated that mjthm4, mjthm3 and mjthm2 shared high homology with known invertebrate multi-repeat β-thymosins. These proteins are ubiquitously expressed in all of the examined tissues and the transcriptional level were highest in the intestine. Further investigation revealed that the mjthm4, mjthm3 and mjthm2 were remarkably up-regulated 6 h after WSSV infection. Moreover, while mjthm4 transcriptional levels displayed no changes, mjthm3 and mjthm2 levels decreased in the virus-resistant shrimps. The results indicate that mjthm4, mjthm3 and mjthm2 are novel multi-repeat β-thymosin homologues, have a close relationship with WSSV infection, and might contribute to a better understanding of host defense and/or virus invasion interactions in shrimps.
Ma J, Ruan L, Xu X, Gao Z. Acta Oceanol Sin. 2016, 35(4): 44-50.