Purification of calcium-sensitive regulatory protein of platelets which inhibits the gelation of actin
Im, T.; Kamitani, T.; Tatsumi, N.; Okuda, K.; Kusunose, M.
Biochemical and Biophysical Research Communications 107(1): 173-180
1982
ISSN/ISBN: 0006-291X PMID: 7126202 Document Number: 184279
Ca2+-sensitive regulatory protein of human platelets, which inhibits the gelation of actin, was purified by DEAE-Sepharose and an affinity column using actin as a ligand. The protein was a single polypeptide chain with an average MW of 90,000, and it bound to actin and inhibited its gelation at concentrations from 10-6-10-7 M of free Ca. Since the protein existed in the form of a complex with actin even though at a concentration < 10-7 M of free Ca, binding and dissociation of actin and the protein appeared to be dependent on the concentration of free Ca, and complete dissociation was not seen.