we have tested the hypothesis that the mechanism of platelet-derived growth factor ( pdgf ) and phorbol diester action to decrease the apparent affinity of the epidermal growth factor ( egf ) receptor is the phosphorylation of the egf receptor at the ca2+/phospholipid-dependent protein kinase ( protein kinase c ) phosphorylation site , threonine 654 .
C0031715
phosphorylation
C0033640
protein kinase