Linked Life Data

19188261

Source:http://linkedlifedata.com/resource/pubmed/id/19188261

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2009-3-18
pubmed:databankReference
pubmed:abstractText
Phosphoinositides (PIs) play a major role in eukaryotic cells, despite being a minor component of most membranes. This is the first report on PI metabolism in a bryophyte, the moss Physcomitrella patens. Moss PI composition is similar to that of other land plants growing under normal conditions. In contrast to the large number of PIPK genes present in flowering plants, the P. patens genome encodes only two type I/II PIPK genes, PpPIPK1 and PpPIPK2, which are very similar at both the nucleotide and protein product levels. However, the expression of the two genes is differentially regulated, and in vitro biochemical characterization shows that the resulting enzymes have different substrate specificities. PpPIPK1 uses PtdIns4P and PtdIns3P with similar preference and also metabolizes PtdIns(3,4)P(2) to produce PtdIns(3,4,5)P(3), a PI not yet detected in intact plant cells. PpPIPK2 prefers PtdIns as substrate and is much less active towards PtdIns4P and PtdIns3P. Thus, PpPIPK2 shows properties reminiscent of both PtdInsP-kinase and PtdIns-kinases. Moreover, a substitution of glutamic acid by alanine in the activation loop drastically reduced PpPIPK1 activity and altered the substrate specificity to PtdIns5P being the preferred substrate compared with PtdIns4P and PtdIns3P. These findings demonstrate that the substrate specificity of plant PIPKs is determined in a plant-specific manner, which provides new insights into the regulatory modes of PIPK activity in plants.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
1471-9053
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
50
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
595-609
pubmed:dateRevised
2010-12-3
pubmed:meshHeading
pubmed:year
2009
pubmed:articleTitle
Characterization of phosphatidylinositol phosphate kinases from the moss Physcomitrella patens: PpPIPK1 and PpPIPK2.
pubmed:affiliation
Department of Biochemistry, Center for Chemistry and Chemical Engineering, Lund University, PO Box 124, SE-22100 Lund, Sweden.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't