title: Non-requirement of calcium on protamine phosphorylation by calcium-activated, phospholipid-dependent protein kinase.
abstract: Phosphorylation of clupeine sulfate by purified rat brain calcium-activated, phospholipid-dependent protein kinase (protein kinase C) was studied. In the absence of Ca2+, phosphatidylserine and diolein markedly stimulated its phosphorylation. However Ca2+ did not stimulate but inhibit this phosphorylation about 30% in the presence of phospholipids. Random polymer (Arg, Ser) 3:1 and (Lys, Ser) 3:1 could be phosphorylated by protein kinase C. In the presence of phospholipids Ca2+ is not needed for the phosphorylation of polymer (Arg, Ser) 3:1, while Ca2+ is necessary for polymer (Lys, Ser) 3:1. Non-requirement of Ca2+ on clupeine phosphorylation by protein kinase C is briefly discussed.
mesh_terms: D002118:Calcium / Q000494:pharmacology*; D006657:Histones / Q000378:metabolism; D010743:Phospholipids / Q000494:pharmacology; D010766:Phosphorylation; D011479:Protamines / Q000378:metabolism*; D011493:Protein Kinase C / Q000494:pharmacology*
chemical_list: D006657:Histones; D010743:Phospholipids; D011479:Protamines; D011493:Protein Kinase C; D002118:Calcium