Premium
Proteolytic modification of membrane‐associated phospholipase C‐β by μ‐calpain enhances its activation by G‐protein βγ subunits in human platelets
Author(s) -
Banno Yoshiko,
Asano Tomiko,
Nozawa Yoshinori
Publication year - 1994
Publication title -
febs letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.593
H-Index - 257
eISSN - 1873-3468
pISSN - 0014-5793
DOI - 10.1016/0014-5793(94)80134-7
Subject(s) - calpain , phospholipase c , pi , protease , thrombin , biochemistry , enzyme , phospholipase , phosphoinositide phospholipase c , g protein , neutral protease , chemistry , platelet activation , platelet , biology , signal transduction , immunology
Membrane‐associated phosphoinositide‐phospholipase C (PI‐PLC)‐β (150 kDa) and its truncated forms (100 kDa and 45 kDa) were purified from human platelets. The 100 kDa PI‐PLC‐β was found to be activated to a greater extent by brain G‐protein βγ subunits compared to the intact 150 kDa enzyme. Furthermore, treatment with μ‐calpain of the intact PI‐PLC‐β (150 kDa) caused a marked augmentation of its activation by βγ subunits. This enhanced PLC activation by βγ subunits was due to truncation by μ‐calpain, producing a 100 kDa PI‐PLC, but not by another protease,thrombin.