Hsp30, the integral plasma membrane heat shock protein of Saccharmyces cerevisiae, is a stress-inducible regulator of plasma membrane H+-ATPase
AUTOR(ES)
Piper, Peter. W.
FONTE
Cell Stress Society International
RESUMO
Saccharomyces cerevisiae has a single integral plasma membrane heat shock protein (Hsp). This Hsp30 is induced by several stresses, including heat shock, ethanol exposure, severe osmostress, weak organic acid exposure and glucose limitation, Plasma membrane H+-ATPase activities of heat shocked and weak acid-adapted, hsp30 mutant and wild-type cells, revealted that Hsp30 induction leads to a downregulation of the stress-stimulation of this H+-ATPase. Plasma membrane H+-ATPase activity consumes a substantial fraction of the ATP generated by the cell, a usage that will be increased by the H+-ATPase stimulation occurring with several Hsp30-inducing stresses. Hsp30 might therefore provide an energy conservation role, limiting excessive ATP consumption by plasma membrance H+-ATPase during prolonged stress exposure or glucose limitation, Consistent with the role of Hsp30 being energy conservation, Hsp30 null cultures give lower final biomass yields. They also have lower ATP levels, consistent with higher H+-ATPase activity, at the glucose exhaustion stage of batch fermentations (diauxic lag), when Hsp30 is normally induced. Loss of Hsp30 does not affect several strees tolerances but it extends the time needed for cells to adapt to growth under several stressful conditions where the maintenance of homeostasis will demand an unusually high usage of energy. hsp30 is the first yeast gene identified as both weak organic acid-inducible and assisting the adaptation to growth in the presence of these acids.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=312976Documentos Relacionados
- Role of the Plasma Membrane H+-ATPase in K+ Transport.
- Phosphorylation of Serine 303 Is a Prerequisite for the Stress-Inducible SUMO Modification of Heat Shock Factor 1
- ATP-sensitive K+ channels in a plasma membrane H+-ATPase mutant of the yeast Saccharomyces cerevisiae.
- Fusicoccin Binding to Its Plasma Membrane Receptor and the Activation of the Plasma Membrane H+-ATPase (III. Is There a Direct Interaction between the Fusicoccin Receptor and the Plasma Membrane H+-ATPase?).
- H+-ATPase Activity from Storage Tissue of Beta vulgaris1: IV. N,N′-Dicyclohexylcarbodiimide Binding and Inhibition of the Plasma Membrane H+-ATPase
