Addition of glucose to cells of the yeast Saccharomyces cerevisiae causes rapid activation of plasma membrane H(+)-ATPase and a stimulation of cellular H+ extrusion. We show that addition of diacylglycerol and other activators of protein kinase C to intact cells also activates the H(+)-ATPase and causes at the same time a stimulation of H+ extrusion from the cells. Both effects are reversed by addition of staurosporine, a protein kinase C inhibitor. Addition of staurosporine or calmidazolium, an inhibitor of Ca2+/calmodulin-dependent protein kinases, separately, causes a partial inhibition of glucose-induced H(+)-ATPase activation and stimulation of cellular H+ extrusion; together they cause a more potent inhibition. Addition of neomycin, which complexes with phosphatidylinositol 4,5-bisphosphate, or addition of compound 48/80, a phospholipase C inhibitor, also causes near complete inhibition. Diacylglycerol and other protein kinase C activators had no effect on the activity of the K(+)-uptake system and the activity of trehalase and glucose-induced activation of the K(+)-uptake system and trehalase was not inhibited by neomycin, supporting the specificity of the effects observed on the H(+)-ATPase. The results support a model in which glucose-induced activation of H(+)-ATPase is mediated by a phosphatidylinositol-type signaling pathway triggering phosphorylation of the enzyme both by protein kinase C and one or more Ca2+/calmodulin-dependent protein kinases.

• PMID: 8061044
• DOI full text
• PubMed
• PubTator

Reference Type

Journal Article | Research Support, Non-U.S. Gov't

Authors

Brandão RL, de Magalhães-Rocha NM, Alijo R, Ramos J, Thevelein JM

Primary Lit For

PMA1

Additional Lit For

Review For