MODULATION OF LAMINARINASE ACTIVITY BY CA-2+, DCAMP, PHORBOL-ESTER AND DIACYLGLYCEROL IN PLANT-CELLS

Reagents known to modulate the intracellular level of Ca2+, CAMP or Ca2+ phospholipid-dependent protein kinase activity efficiently regulated laminarinase activity in suspended Rubus cells. Thus second messengers or related factors could alter the cell response to a sugar elicitor. Furthermore, two proteins of 15 and 35 000 in enzyme extracts of cells incubated with liposomes containing diacylglycerol and phosphatidylserine could be phosphorylated while no change occurred in extracts from control cells. The results suggest that protein kinases may play a major role in the control of laminarinase activity. © 1990.