Lpx1p links glucose-induced calcium signaling and plasma membrane H+-ATPase activation in Saccharomyces cerevisiae cells

• Published in: FEMS yeast research Vol. 18; no. 1
• Main Authors: Castanheira, Diogo Dias, Santana, Eduardo Perovano, Godoy-Santos, Fernanda, Diniz, Raphael Hermano Santos, Faria-Oliveira, Fábio, Pereira, Renata Rebeca, Trópia, Maria José Magalhães, Castro, Ieso Miranda, Brandão, Rogelio Lopes
• Format: Journal Article
• Language: English
• Published: England Oxford University Press 01-02-2018
• Subjects: Calcium (intracellular); Calcium - metabolism; Calcium Signaling; Calcium signalling; Cell activation; Cell Membrane - metabolism; Cytosol - metabolism; Gene Expression Regulation, Fungal; Glucose; Glucose - metabolism; H+-transporting ATPase; Hydrogen; Intracellular signalling; Kinases; Phospholipases A - metabolism; Phosphorylation; Plasma; Protein kinase; Proteolysis; Proton-Translocating ATPases - metabolism; Saccharomyces cerevisiae - metabolism; Saccharomyces cerevisiae Proteins - metabolism; Serine; Signal transduction; Tubulin; Lpx1; plasma membrane H+-ATPase; Saccharomyces cerevisiae; calcium signaling
• ISSN: 1567-1364; 1567-1356; 1567-1364
• DOI: 10.1093/femsyr/fox088

In yeast, as in other eukaryotes, calcium plays an essential role in signaling transduction to regulate different processes. Many pieces of evidence suggest that glucose-induced activation of plasma membrane H+-ATPase, essential for yeast physiology, is related to calcium signaling. Until now, no protein that could be regulated by calcium in this context has been identified. Lpx1p, a serine-protease that is also involved in the glucose-induced activation of the plasma membrane H+-ATPase, could be a candidate to respond to intracellular calcium signaling involved in this process. In this work, by using different approaches, we obtained many pieces of evidence suggesting that the requirement of calcium signaling for activation of the plasma membrane H+-ATPase is due to its requirement for activation of Lpx1p. According to the current model, activation of Lpx1p would cause hydrolysis of an acetylated tubulin that maintains the plasma membrane H+-ATPase in an inactive state. Therefore, after its activation, Lpx1p would hydrolyze the acetylated tubulin making the plasma membrane H+-ATPase accessible for phosphorylation by at least one protein kinase.