Molecular isolation and characterization of translationally controlled tumor protein (TCTP) gene fromMacrobrachium rosenbergii

Translationally controlled tumor protein (TCTP) or fortilin is a highly conserved protein among eukaryotes and has important biological roles including anti-apoptotic activity which involves the elimination of virus-infected cells. In this study, the full-length cDNA ofMacrobrachium rosenbergiiTCTP (MrTCTP) was isolated. The cDNA sequence consisted of 783 bp with a 507-bp open reading frame encoding 168 amino acids.MrTCTP demonstrated all major characteristics of TCTP which include (1) highly homologous to TCTP protein family, (2) carrying two TCTP signatures, and (3) contained highly conserved amino acid sequences. The predicted structure ofMrTCTP also revealed typical structure of TCTP which had three major domains including ss-stranded core domain, helical domain, and flexible loop. The predicted molecular mass ofMrTCTP was 18.94 kDa and sequence displays 83.93 and 78.57% identity to that ofEriocheir sinensisTCTP andFenneropenaeus chinensisTCTP, respectively. Phylogenetic analysis revealed that the deduced amino acid sequence ofMrTCTP was clustered into the invertebrate branch along with the sequences from arthropods and crustaceans. The mRNA expression showed thatMrTCTPexpressed in every tissue examined, preferentially in hepatopancreas and muscle. In addition,MrTCTPexpression in the muscle was upregulated at 1 to 4 days after infection withM. rosenbergiinodavirus (MrNV). Finally, silencing ofMrTCTP increased mortality rates post-MrNV challenge. Taken together, the study shows thatMrTCTP may play an important role in shrimp immune response againstMrNV infection.