Tuyển tập các báo cáo nghiên cứu về y học được đăng trên tạp chí y học Critical Care giúp cho các bạn có thêm kiến thức về ngành y học đề tài: Growth arrest-specific protein 6 (GAS6) and the protein C pathway. | Available online http content 11 2 410 Letter Growth arrest-specific protein 6 GAS6 and the protein C pathway Shi-Sheng Li Department of Molecular and Experimental Medicine The Scripps Research Institute 10550 North Torrey Pines Road La Jolla CA 92037 USA Corresponding author Shi-Sheng Li sshli@ Published 18 April 2007 This article is online at http content 11 2 410 2007 BioMed Central Ltd See related research by Gibot et al. http content 11 1 R8 Growth arrest-specific protein 6 GAS6 shares a high degree of similarity with protein S PS a cofactor for the protein C PC anticoagulant pathway. PS consists of an N-terminal Y-carboxyglutamic acid Gla domain a thrombinsensitive region TSR four epidermal growth factor-like domains and a large C-terminal sex hormone-binding globulin-like domain. The TSR loop which is not present in GAS6 is a prerequisite for PS cofactor activity and facilitates the binding of the Gla domain of PS to the membrane phospholipids of activated platelets endothelial cells and platelet microparticles where the PC anticoagulant pathway is manifested. It is predicted that GAS6 does not have a cofactor role similar to that of PS for the anticoagulant activity of activated protein C APC 1 2 . However it is rather premature to exclude a possible interaction between GAS6 and PC APC. Recent studies suggest that the PS Gla domain itself may interact directly with the Gla domain of APC on cell membrane surfaces. The Gla domains of PS and GAS6 have the highest sequence homology among all the modules. Seven out of a cluster of nine amino acid residues in the Gla domain of PS that have been identified as being of critical importance for putative binding to the APC Gla domain are identical in the GAS6 Gla domain Leu21 Arg28 Asn33 Asp34 Pro35 Tyr41 Leu45 whereas the other two residues are highly conserved Asn23 Lys24 in PS Ser23 Arg24 in GAS6 2 3 . The Gla domain of APC also interacts directly with the endothelial
