Glucose‐stimulated cAMP increase may be mediated by intracellular acidification in Saccharomyces cerevisiae

FEBS Letters

Guerritore, Andrea¹  Tortora, Paolo¹  Hanozet, Giorgio M.¹  Caspani, Giorgio¹ 

[1] Dipartimento di Fisiologia e Biochimica generali, Via Celoria 26, I-20133 Milano, Italy

关键词: Yeast;    cAMP;    Glucose;    Membrane potential;    Intracellular acidification;    TPP+;    tetraphenylphosphonium;    FCCP;    carbonyl cyanide p-trifluoromethoxyphenylhydrazone;    Mes;    4-morpholineethanesulfonic acid;   

DOI  :  10.1016/0014-5793(85)81342-9

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

It has been reported that addition of glucose to cells of Saccharomyces cerevisiae grown on a sugar-free medium causes a peak of intracellular cAMP levels. Also, it has been proposed that this effect might be mediated by plasma membrane depolarization. However, here, we observed a hyperpolarizing effect of glucose in S. cerevisiae and, in addition, no change in cAMP levels when depolarization was induced by valinomycin in the presence of K⁺. In contrast, treatments that induced a rapid intracellular acidification such as addition of the protonophore carbonyl cyanide p-trifluoromethoxyphenylhydrazone at pH 5.5 but not at pH 8.0, extracellular pH shift from 8.5 to 3.5, and glucose itself, also increased the cyclic nucleotide. Thus, our data strongly support the hypothesis that intracellular acidification mediates the effect of glucose on cAMP levels.

【 授权许可】

Unknown