Characterization, homology modeling and expression of the putative translationally controlled tumor protein gene from giant river prawn Macrobrachium rosenbergii (de Man)

The translationally controlled tumor protein (TCTP) is a multifunctional protein that promotes cell growth and viability. The TCTP has been associated with shrimp immune response by high levels being detected during the onset of white spot syndrome virus (WSSV) infection. The present study characterized the putative TCTP gene from the giant river prawn M. rosenbergii and investigated a putative function of this protein in response to Aeromonas hydrophila injection. A full-length cDNA sequence was obtained by assembly of short reads of RNA sequences from a 454-transcriptome dataset of river prawns and was designated as putative MrTCTP. The three-dimensional (3D) structure of MrTCTP was constructed using a homology modeling approach to predict the functional properties of the protein. Expression of MrTCTP was assessed in hepatopancreas tissues 96 h after injection using quantitative real-time polymerase chain reaction. The 704 bp full length cDNA of MrTCTP contained an open reading frame of 507 bp encoding a polypeptide of 168 amino acid residues. The conserved signature sequences of TCTP, I45-D55 and F123Y145 shared 61-92.3% similarity with the previously identified TCTP. The quality assessment and parameter validation indicated that the putative MrTCTP modeled structure was reliable. Expression levels of MrTCTP were significantly different (p < 0.05) between the control and infected prawns during 16-48 h. Transcript levels significantly increased 1.21-fold at 16 h to 2.26-fold at 48 h. The results suggested that the putative MrTCTP may be involved in the anti-apoptotic mechanism of river prawn.