The roles of cysteines in the heme domain of human soluble guanylate cyclase  

作　　者：Fang Fang Zhong Xiao Xiao Liu Jie Pan Zhong Xian Huang Xiang Shi Tan 

机构地区：[1]Department of Chemistry,Fudan University,Shanghai 200433,China [2]Institutes of Biomedical Sciences,Fudan University,Shanghai 200433,China

出　　处：《Chinese Chemical Letters》2012年第8期973-976,共4页中国化学快报（英文版）

基　　金：supported partly by Shanghai Pujiang Talent Project (No.:08PJ14017);the National Natural Science Foundation of China (Nos.:20771029 and 91013001);Shanghai Leading Academic Discipline Project (No. B108)

摘　　要：Soluble guanylate cyclase（sGC） is a critical heme-containing enzyme involved in NO signaling.The dimerization of sGC subunits is necessary for its bioactivity and its mechanism is a striking and an indistinct issue.The roles of heme domain cysteines of the sGC on the dimerization and heme binding were investigated herein.The site-directed mutations of three conserved cysteines（C78A,C122A and C174S） were studied systematically and the three mutants were characterized by gel filtration analysis,UV-vis spectroscopy and heme transfer examination.Cys78 was involved in heme binding but not referred to the dimerization,while Cys174 was demonstrated to be involved in the homodimerization.These results provide new insights into the cysteine-related dimerization regulation of sGC.Soluble guanylate cyclase（sGC） is a critical heme-containing enzyme involved in NO signaling.The dimerization of sGC subunits is necessary for its bioactivity and its mechanism is a striking and an indistinct issue.The roles of heme domain cysteines of the sGC on the dimerization and heme binding were investigated herein.The site-directed mutations of three conserved cysteines（C78A,C122A and C174S） were studied systematically and the three mutants were characterized by gel filtration analysis,UV-vis spectroscopy and heme transfer examination.Cys78 was involved in heme binding but not referred to the dimerization,while Cys174 was demonstrated to be involved in the homodimerization.These results provide new insights into the cysteine-related dimerization regulation of sGC.

关 键 词：Human soluble guanylate cyclase sGC Heine domain Cysteine DIMERIZATION 

分 类 号：Q513[生物学—生物化学] Q517