An osmotically induced cytosolic Ca2+ transient activates calcineurin signaling to mediate ion homeostasis and salt tolerance of Saccharomyces cerevisiae

Tracie K. Matsumoto, Amanda J. Ellsmore, Stephen G. Cessna, Philip S. Low, José M. Pardo, Ray A. Bressan, Paul M. Hasegawa

Research output: Contribution to journalArticle

112 Scopus citations

Abstract

Hyperosmotic stress caused by NaCl, LiCl, or sorbitol induces an immediate and short duration (∼1 min) transient cytosolic Ca2+ ([Ca2+]cyt) increase (Ca2+-dependent aequorin luminescence) in Saccharomyces cerevisiae cells. The amplitude of the osmotically induced [Ca2+]cyt transient was attenuated by the addition of chelating agents EGTA or BAPTA, cation channel pore blockers, competitive inhibitors of Ca2+ transport, or mutations (cch1Δ or mid1Δ) that reduce Ca2+ influx, indicating that Ca2+ Caext2+ is a source for the transient. An osmotic pretreatment (30 min) administered by inoculating cells into media supplemented with either NaCl (0.4 or 0.5 M) or sorbitol (0.8 or 1.0 M) enhanced the subsequent growth of these cells in media containing 1 M NaCl or 2 M sorbitol. Inclusion of EGTA in the osmotic pretreatment media or the cch1Δ mutation reduced cellular capacity for NaCl but not hyperosmotic adaptation. The stress-adaptive effect of hyperosmotic pretreatment was mimicked by exposing cells briefly to 20 mM CaCl2. Thus, NaCl- or sorbitol-induced hyperosmotic shock causes a [Ca2+]cyt transient that is facilitated by Ca2+ influx, which enhances ionic but not osmotic stress adaptation. NaCl-induced ENA1 expression was inhibited by EGTA, cch1Δ mutation, and FK506, indicating that the [Ca2+]cyt transient activates calcineurin signaling to mediate ion homeostasis and salt tolerance.

Original languageEnglish (US)
Pages (from-to)33075-33080
Number of pages6
JournalJournal of Biological Chemistry
Volume277
Issue number36
DOIs
StatePublished - Sep 6 2002

ASJC Scopus subject areas

  • Biochemistry
  • Molecular Biology
  • Cell Biology

Fingerprint Dive into the research topics of 'An osmotically induced cytosolic Ca<sup>2+</sup> transient activates calcineurin signaling to mediate ion homeostasis and salt tolerance of Saccharomyces cerevisiae'. Together they form a unique fingerprint.

Cite this