tailieunhanh - Báo cáo khoa học: Characterization of chitinase-like proteins (Cg-Clp1 and Cg-Clp2) involved in immune defence of the mollusc Crassostrea gigas

Chitinase-like proteins have been identified in insects and mammals as non-enzymatic members of the glycoside hydrolase family 18. Recently, the first molluscan chitinase-like protein, namedCrassostrea gigas(Cg)-Clp1, was shown to control the proliferation and synthesis of extracellular matrix components of mammalian chondrocytes. | ễFEBS Journal Characterization of chitinase-like proteins Cg-Clp1 and Cg-Clp2 involved in immune defence of the mollusc Crassostrea gigas Fabien Badariotti Christophe Lelong Marie-Pierre Dubos and Pascal Favrel Université de Caen Basse-Normandie IBFA UMR M100 IFREMER Physiologie et Ecophysiologie des Mollusques Marins Laboratoire de Biologie et Biotechnologies Marines Caen France Keywords chitinase-like protein Crassostrea gigas immunity lectin mollusk Correspondence P. Favrel Universite de Caen Basse-Normandie IBFA UMR M100 IFREMER Physiologie et Ecophysiologie des Mollusques Marins 14032 Caen cedex France Fax 33 231565346 Tel 33 231565361 E-mail Received 22 February 2007 revised 10 May 2007 accepted 23 May 2007 Chitinase-like proteins have been identified in insects and mammals as non-enzymatic members of the glycoside hydrolase family 18. Recently the first molluscan chitinase-like protein named Crassostrea gigas Cg -Clp1 was shown to control the proliferation and synthesis of extracellular matrix components of mammalian chondrocytes. However the precise physiological roles of Cg-Clp1 in oysters remain unknown. Here we report the cloning and the characterization of a new chitinase-like protein Cg-Clp2 from the oyster Crassostrea gigas. Gene expression profiles monitored by quantitative RT-PCR in adult tissues and through development support its involvement in tissue growth and remodelling. Both Cg-Clp1- and Cg-Clp2-encoding genes were transcriptionally stimulated in haemocytes in response to bacterial lipopolysaccharide challenge strongly suggesting that these two close paralogous genes play a role in oyster immunity. doi Glycoside hydrolase family 18 GH18 is a phylogenet-ically conserved group of proteins present in eukaryotes prokaryotes and viruses. The GH18 family is characterized by a Glyco_18 domain adopting an a b 8 triose phosphate isomerase-barrel structure that consists of a specific arrangement