Linked Life Data

12569407

Source:http://linkedlifedata.com/resource/pubmed/id/12569407

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
2003-2-5
pubmed:abstractText
C(4) phosphoenolpyruvate carboxylase (PEPCase: EC 4.1.1.31) is subjected to in vivo regulatory phosphorylation by a light up-regulated, calcium-independent protein kinase. Salt stress greatly enhanced phosphoenolpyruvate carboxylase-kinase (PEPCase-k) activity in leaves of Sorghum. The increase in PEPCase-k anticipated the time course of proline accumulation thereby suggesting that water stress was not involved in the kinase response to salt. Moreover, osmotic stress seemed not to be the main factor implicated, as demonstrated by the lack of effect when water availability was restricted by mannitol. In contrast, LiCl (at a concentration of 10 mM in short-term treatment of both excised leaves and whole plants) mimicked the effects of 172 mM NaCl salt-acclimation, indicating that the rise in PEPCase-k activity resulted primarily from the ionic stress. Both NaCl and LiCl treatments increased the activity of a Ca(2+)-independent, 35 kDa kinase, as demonstrated by an in-gel phosphorylation experiment. Short-term treatment of excised leaves with NaCl or LiCl partially reproduces the effects of whole plant treatments. Finally, salinization also increased PEPCase-k activity and the phosphorylation state of PEPCase in darkened Sorghum leaves. This fact, together with increased malate production during the dark period, suggests a shift towards mixed C(4) and crassulacean acid metabolism types of photosynthesis in response to salt stress.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0032-0935
pubmed:author
pubmed:issnType
Print
pubmed:volume
216
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
648-55
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2003
pubmed:articleTitle
Characterization of salt stress-enhanced phosphoenolpyruvate carboxylase kinase activity in leaves of Sorghum vulgare: independence from osmotic stress, involvement of ion toxicity and significance of dark phosphorylation.
pubmed:affiliation
Departamento de Biología Vegetal, Facultad de Biología, Universidad de Sevilla, Avenida Reina Mercedes no. 6, 41012 Seville, Spain. sgarma@us.es
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't