Linked Life Data

18073213

Source:http://linkedlifedata.com/resource/pubmed/id/18073213

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
2008-2-4
pubmed:abstractText
Stress responses in both plants and yeast utilize calcium-mediated signaling. A yeast strain, K616, which lacks Ca(2+) pumps, requires micromolar Ca(2+) for growth. In medium containing 100 microM Ca(2+), K616 can withstand osmotic stress (750 mM sorbitol) and ionic stress (300 mM KCl) but not hypersodic stress (300 mM NaCl). Heterologous expression of the endoplasmic reticulum-located Arabidopsis thaliana Ca(2+)-ATPase, ACA2, permits K616 to grow under NaCl stress even in Ca(2+)-depleted medium. All stresses tested generated transient elevation of cytosolic Ca(2+) in wild type yeast, K601, whereas NaCl alone induced prolonged elevation of cytosolic Ca(2+) in K616. Both the Ca(2+) transient and survival of cultures subjected to NaCl stress was similar for the ACA2 transformant and K601. However, whereas K601 maintained low cytosolic Na(+) predominantly by pumping it out across the plasma membrane, the transformant sequestered Na(+) in internal organelles. This sequestration requires the presence of an endomembrane Na(+)/H(+)-antiporter, NHX1, which does not play a significant role in salt tolerance of wild type yeast except at acidic pH. Transcript levels of the plasma membrane Na(+)-ATPase, ENA1, were strongly induced only in K601, whereas NHX1 was strongly induced in both K601 and the ACA2 transformant. The calmodulin kinase inhibitor KN62 significantly reduced the salt tolerance of the ACA2 transformant and the transcriptional induction of NHX1. Thus, the heterologous expression of a plant endomembrane Ca(2+) pump results in the rapid depletion of cytosolic Ca(2+) and the activation of an alternate mechanism for surviving saline stress.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
8
pubmed:volume
283
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
3497-506
pubmed:dateRevised
2010-11-18
pubmed:meshHeading
pubmed:year
2008
pubmed:articleTitle
A plant Ca2+ pump, ACA2, relieves salt hypersensitivity in yeast. Modulation of cytosolic calcium signature and activation of adaptive Na+ homeostasis.
pubmed:affiliation
National Centre for Biological Sciences, Bangalore 560 065, India.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't