Linked Life Data

15356005

Source:http://linkedlifedata.com/resource/pubmed/id/15356005

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
46
pubmed:dateCreated
2004-11-8
pubmed:abstractText
Most types of plant phospholipase D (PLD) require Ca(2+) for activity, but how Ca(2+) affects PLD activity is not well understood. We reported previously that Ca(2+) binds to the regulatory C2 domain that occurs in the N terminus of the Ca(2+)-requiring PLDs. Using Arabidopsis thaliana PLDbeta and C2-deleted PLDbeta (PLDbetacat), we now show that Ca(2+) also interacts with the catalytic regions of PLD. PLDbetacat exhibited Ca(2+)-dependent activity, was much less active, and required a higher level of Ca(2+) than the full-length PLDbeta. Ca(2+) binding of the proteins was stimulated by phospholipids; phosphatidylserine was the most effective among those tested. Scatchard plot analysis of Ca(2+) binding data yielded an estimate of 3.6 high affinity (K(d) = 29 mum) binding sites on PLDbeta. The Ca(2+)-PLDbetacat interaction increased the affinity of the protein for the activator, phosphatidylinositol 4,5-bisphosphate, but not for the substrate, phosphatidylcholine. This is in contrast to the effect of Ca(2+) binding to the C2 domain, which stimulates phosphatidylcholine binding but inhibits phosphatidylinositol 4,5-bisphosphate binding of the domain. These results demonstrate the contrasting and complementary effects of the Ca(2+)- and lipid-binding properties of the C2 and catalytic domains of plant PLD and provide insight into the mechanism by which Ca(2+) regulates PLD activity.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
12
pubmed:volume
279
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
47833-9
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2004
pubmed:articleTitle
Evidence for and characterization of Ca2+ binding to the catalytic region of Arabidopsis thaliana phospholipase Dbeta.
pubmed:affiliation
Department of Biochemistry, Kansas State University, Manhattan, Kansas 66506, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, Non-P.H.S., Research Support, Non-U.S. Gov't