title: A prawn transglutaminase: molecular characterization and biochemical properties.
abstract: In this study, we report the bioinformatics characterization, gene expression, transglutaminase activity and coagulation assays of transglutaminase (TGase) of freshwater prawn Macrobrachium rosenbergii identified from the constructed cDNA library by GS FLX™ technology. Even though, TGase have sequence similarity, they differ extensively in their substrate specificity and are thought to play an important in variety of functions such as development, tissue differentiation and immune responses etc. Gene expression studies show that MrTGase is widely distributed in the tissues such as heart, muscle, intestine, brain, etc., but higher amounts are found in hemocyte. Results of TGase mRNA relative expression in hemocyte, before and after infected with white spot syndrome baculovirus (WSBV) and Vibrio harveyi show that the gene expression initially increases up to 24 h and then it falls down. Coagulation assay results showed that the endogenous TGase is involved in the rapid assembly of a specific, plasma clotting protein. Structural studies show that MrTGase contains a typical TGc domain between 323 and 424, and two putative integrin-binding motifs at Arg(180)-Gly(181)-Asp(182) and Arg(269)-Gly(270)-Asp(271). The predicted 3D model of MrTGase contains 47.04% coils (366 amino acid residues), 26.74% extended strand (208 residues), 21.72% α-helix (169 residues) and 4.5% beta turns (35 residues). BLASTp analysis of MrTGase exhibited high sequence similarities with other crustacean TGase, with the highest observed in white shrimp (77.1%). Moreover, the phylogenetic analysis also showed that MrTGase clustered with the other members of crustacean TGase. Overall, these results suggested that MrTGase is a major and functional TGase of M. rosenbergii for haemolymph coagulation and also in spread of infection.
authors.affiliation: Division of Fisheries Biotechnology & Molecular Biology, Department of Biotechnology, Faculty of Science and Humanities, SRM University, Kattankulathur, 603 203 Chennai, Tamil Nadu, India. Electronic address: jesuaraj@hotmail.com.
authors.forename: Jesu
authors.initials: J
authors.lastname: Arockiaraj
authors.forename: Annie J
authors.initials: AJ
authors.lastname: Gnanam
authors.forename: Rajesh
authors.initials: R
authors.lastname: Palanisamy
authors.forename: Venkatesh
authors.initials: V
authors.lastname: Kumaresan
authors.forename: Prasanth
authors.initials: P
authors.lastname: Bhatt
authors.forename: Muthukumaresan Kuppusamy
authors.initials: MK
authors.lastname: Thirumalai
authors.forename: Arpita
authors.initials: A
authors.lastname: Roy
authors.forename: Mukesh
authors.initials: M
authors.lastname: Pasupuleti
authors.forename: Marimuthu
authors.initials: M
authors.lastname: Kasi
authors.forename: Akila
authors.initials: A
authors.lastname: Sathyamoorthi
authors.forename: Abirami
authors.initials: A
authors.lastname: Arasu
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D016367:Baculoviridae; D001483:Base Sequence; D006458:Hemolymph / Q000502:physiology; D008969:Molecular Sequence Data; D033541:Palaemonidae / Q000378:metabolism* / Q000382:microbiology / Q000821:virology; D010802:Phylogeny; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D012333:RNA, Messenger / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D014018:Tissue Distribution; D011503:Transglutaminases / Q000737:chemistry / Q000145:classification / Q000378:metabolism*
chemical_list: D012333:RNA, Messenger; D011503:Transglutaminases
keywords: Coagulation; Gene expression; Macrobrachium rosenbergii; Pathogen; Transglutaminase