Elevated calcium level induces calcium-dependent proteolysis of A-CAM (N-cadherin) in heart--analysis by detergent-treated model.
Calcium overload induces cardiac muscle cell dysfunction in cardiovascular diseases. We investigated the effects of elevated calcium level on adherens-junction-specific cell adhesion molecule (A-CAM). Incubation of Triton X-100-treated canine heart homogenate in the presence of Ca2+ reduced the content of A-CAM. Reduction in A-CAM requires milli-molar Ca2+ and was inhibited by protease inhibitors, leupeptin and calpeptin. Immunohistochemical observation revealed that m-calcium-activated neutral protease (m-CANP) was colocalized with A-CAM in intercalated disks. These data suggested that m-CANP proteolyzes A-CAM in response to calcium overload in cardiac muscle.
Sato
N
N
Department of Internal Medicine, Center for Adult Diseases, Osaka, Japan.
Fujio
Y
Y
Yamada-Honda
F
F
Funai
H
H
Wada
A
A
Kawashima
S
S
Awata
N
N
Shibata
N
N
D000818:Animals; D015820:Cadherins / Q000378:metabolism*; D002118:Calcium / Q000502:physiology*; D002154:Calpain / Q000378:metabolism; D002318:Cardiovascular Diseases / Q000378:metabolism; D004285:Dogs; D019084:Fluorescent Antibody Technique, Indirect; D009206:Myocardium / Q000378:metabolism*; D017830:Octoxynol / Q000737:chemistry
D015820:Cadherins; D017830:Octoxynol; D002154:Calpain; D002118:Calcium