Molecular cloning and expression analysis of the interferon-γ-inducible lysosomal thiol reductase gene from the shrimp Penaeus monodon
The interferon-γ-inducible lysosomal thiol reductase enzymes (GILT) have been shown to play an important role in the processing of exogenous antigens by catalyzing disulfide bond reduction, that facilitates unfolding of the native protein antigen to simplify further cleavage by cellular proteases. In this study a Penaeus monodon GILT (PmGILT) gene was isolated from an EST library of white spot syndrome virus (WSSV)-infected P. monodon. The full-length cDNA of the PmGILT gene was 780 bp and contained an open reading frame of 657 bp that encoded 218 amino acid residues with a predicted protein molecular weight of 24 kDa. The deduced amino acid sequence of PmGILT contains an active site CXXS motif, a GILT signature sequence (CQHGX2ECX2NX4C) and 10 conserved cysteines together with other signature characteristics of GILT proteins. RT-PCR analysis showed that the PmGILT mRNA expression level was clearly up-regulated in the lymphoid organ of both the LPS-induced and WSSV-infected shrimp, compared to normal shrimp. In response to WSSV infection, the penaeid shrimp JAK/STAT pathway is reported to play an important role in the lymphoid organ. We hypothesize that this activated STAT may stimulate GILT expression so that it can be involved in the shrimp immune response system.
KeywordsShrimp (Penaeus monodon) Interferon-gamma-inducible lysosomal thiol reductase (GILT) Gene expression Lipopolysaccharide (LPS) White spot syndrome virus (WSSV)
We would like to thank the Office of the Higher Education Commission, Thailand for support through a grant funded to Ms. Kittima Kongton under a program from the Strategic Scholarships for Frontier Research Network for the Joint Ph.D. Program Thai Doctoral degree. This work was also supported by Prince of Songkla university grant. We thank Dr. Brian Hodgson for assistance with English language.
- 22.Liu N, Zhang S, Liu Z, Gaowa S, Wang Y (2007) Characterization and expression of gamma-interferon-inducible lysosomal thiol reductase (GILT) gene in amphioxus Branchiostoma belcheri with implications for GILT in innate immune response. Mol Immunol 44:2631–2637. doi: 10.1016/j.molimm.2006.12.013 PubMedCrossRefGoogle Scholar
- 23.He N, Qin Q, Xu X (2005) Differential profile of genes expressed in hemocytes of white spot syndrome virus-resistant shrimp (Penaeus japonicus) by combining suppression subtractive hybridization and differential hybridization. Antiviral Res 66:39–45. doi: 10.1016/j.antiviral.2004.12.010 PubMedCrossRefGoogle Scholar
- 29.Pongsomboon S, Wongpanya R, Tang S, Chalorsrikul A, Tassanakajon A (2008) Abundantly expressed transcripts in the lymphoid organ of the black tiger shrimp, Penaeus monodon, and their implication in immune function. Fish Shellfish Immunol 25:485–493. doi: 10.1016/j.fsi.2008.07.010 PubMedCrossRefGoogle Scholar