Corin mutation R539C from hypertensive patients impairs zymogen activation and generates an inactive alternative ectodomain fragment.
Corin is a cardiac transmembrane serine protease that regulates blood pressure by activating natriuretic peptides. Corin variants have been associated with African Americans with hypertension and heart disease. Here, we report a new mutation in exon 12 of the CORIN gene identified in a family of patients with hypertension. The mutation resulted in R539C substitution in the Fz2 (Frizzled-2) domain of the corin propeptide region. We expressed and characterized the corin R539C mutant in HEK293 cells. As determined by Western blot analysis, the R539C mutation did not alter corin expression in transfected cells but impaired corin zymogen activation. In a pro-atrial natriuretic peptide processing assay, the corin mutant had reduced activity and exhibited a dominant-negative effect on wild-type corin. In addition, the R539C mutation altered corin ectodomain shedding, producing an alternative ~75-kDa fragment that was biologically inactive. Using protease inhibitors and the catalytically inactive corin mutant S985A, we showed that the ~75-kDa fragment was generated by corin autocleavage. We constructed a series of mutants by replacing single or double Arg residues in the corin propeptide and identified Arg-530 in the Fz2 domain as the alternative autocleavage site. Our results show that the corin mutation R539C identified in hypertensive patients impairs corin zymogen activation and causes an alternative autocleavage that reduces corin activity. These data support that human CORIN gene mutations causing impaired corin activity may be an underlying mechanism in hypertension.
Cyrus Tang Hematology Center, Jiangsu Institute of Hematology, the First Affiliated Hospital, Soochow University, Suzhou 215123, China; Thrombosis and Hemostasis Key Laboratory of Ministry of Health, Jiangsu Institute of Hematology, the First Affiliated Hospital, Soochow University, Suzhou 215123, China.
Ningzheng
N
Dong
Cyrus Tang Hematology Center, Jiangsu Institute of Hematology, the First Affiliated Hospital, Soochow University, Suzhou 215123, China.
Chaodong
C
Fang
Cyrus Tang Hematology Center, Jiangsu Institute of Hematology, the First Affiliated Hospital, Soochow University, Suzhou 215123, China; Thrombosis and Hemostasis Key Laboratory of Ministry of Health, Jiangsu Institute of Hematology, the First Affiliated Hospital, Soochow University, Suzhou 215123, China.
Yizhi
Y
Jiang
Cyrus Tang Hematology Center, Jiangsu Institute of Hematology, the First Affiliated Hospital, Soochow University, Suzhou 215123, China.
Tiantian
T
Zhou
Cyrus Tang Hematology Center, Jiangsu Institute of Hematology, the First Affiliated Hospital, Soochow University, Suzhou 215123, China.
Meng
M
Liu
Department of Gerontology, the First Hospital of Yancheng, Yancheng 224001, China.
Jianping
J
Zhou
Departments of Molecular Cardiology, Nephrology, and Hypertension, Cleveland Clinic, Cleveland, Ohio 44195.
Jianzhong
J
Shen
Departments of Molecular Cardiology, Nephrology, and Hypertension, Cleveland Clinic, Cleveland, Ohio 44195.
Koichi
K
Fukuda
Departments of Molecular Cardiology, Nephrology, and Hypertension, Cleveland Clinic, Cleveland, Ohio 44195.
Jun
J
Qin
Cyrus Tang Hematology Center, Jiangsu Institute of Hematology, the First Affiliated Hospital, Soochow University, Suzhou 215123, China; Departments of Molecular Cardiology, Nephrology, and Hypertension, Cleveland Clinic, Cleveland, Ohio 44195. Electronic address: wuq@ccf.org.
Qingyu
Q
Wu
D001665:Binding Sites; D004792:Enzyme Precursors / Q000737:chemistry; D005260:Female; D005786:Gene Expression Regulation; D057809:HEK293 Cells; D006801:Humans; D006973:Hypertension / Q000378:metabolism; D008297:Male; D008957:Models, Genetic; D008958:Models, Molecular; D009154:Mutation; D010455:Peptides / Q000737:chemistry; D010802:Phylogeny; D010957:Plasmids / Q000378:metabolism; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D017422:Sequence Analysis, DNA; D012697:Serine Endopeptidases / Q000235:genetics*
D004792:Enzyme Precursors; D010455:Peptides; C119812:CORIN protein, human; D012697:Serine Endopeptidases