Activation of trehalase by membrane-depolarizing agents in yeast vegetative cells and ascospores

The membrane-depolarizing agents 2,4-dinitrophenol, carbonylcyanide m-chlorophenylhydrazone, and nystatin are known to cause a rapid increase in the cyclic AMP level in fungal cells. Addition of these proton ionophores to yeast stationary-phase cells or ascospores causes an immediate 10-fold increase in trehalase activity. This observation is in agreement with a role for cyclic AMP-induced phosphorylation in the activation process of trehalase. It also provides an explanation for previous results on the induction of trehalose breakdown by 2,4-dinitrophenol in resting yeast cells.