Histones H3 and H4 inhibit protein kinase C specifically

The lysine-rich histone H1 is a preferred substrate for the Ca2+-phospholipid-dependent protein kinase (protein kinase C). Histones H3 and H4 are poor substrates but potent inhibitors of the enzyme. The inhibitory effect of H3 and H4 seems to result mainly from a decreased sensitivity of protein kinase C to stimulation by phosphatidylserine (PS). These observations suggest that site-specific phosphorylation of one histone type can be regulated by other histones.