Linked Life Data

20650897

Source:http://linkedlifedata.com/resource/pubmed/id/20650897

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
38
pubmed:dateCreated
2010-9-13
pubmed:abstractText
Three sequential methylations of phosphoethanolamine (PEA) are required for the synthesis of phosphocholine (PCho) in plants. A cDNA encoding an N-methyltransferase that catalyzes the last two methylation steps was cloned from Arabidopsis by heterologous complementation of a Saccharomyces cerevisiae cho2, opi3 mutant. The cDNA encodes phosphomethylethanolamine N-methyltransferase (PMEAMT), a polypeptide of 475 amino acids that is organized as two tandem methyltransferase domains. PMEAMT shows 87% amino acid identity to a related enzyme, phosphoethanolamine N-methyltransferase, an enzyme in plants that catalyzes all three methylations of PEA to PCho. PMEAMT cannot use PEA as a substrate, but assays using phosphomethylethanolamine as a substrate result in both phosphodimethylethanolamine and PCho as products. PMEAMT is inhibited by the reaction products PCho and S-adenosyl-l-homocysteine, a property reported for phosphoethanolamine N-methyltransferase from various plants. An Arabidopsis mutant with a T-DNA insertion associated with locus At1g48600 showed no transcripts encoding PMEAMT. Shotgun lipidomic analyses of leaves of atpmeamt and wild-type plants generated phospholipid profiles showing the content of phosphatidylmethylethanolamine to be altered relative to wild type with the content of a 34:3 lipid molecular species 2-fold higher in mutant plants. In S. cerevisiae, an increase in PtdMEA in membranes is associated with reduced viability. This raises a question regarding the role of PMEAMT in plants and whether it serves to prevent the accumulation of PtdMEA to potentially deleterious levels.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
1083-351X
pubmed:author
pubmed:issnType
Electronic
pubmed:day
17
pubmed:volume
285
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
29147-55
pubmed:dateRevised
2011-9-20
pubmed:meshHeading
pubmed:year
2010
pubmed:articleTitle
Identification of phosphomethylethanolamine N-methyltransferase from Arabidopsis and its role in choline and phospholipid metabolism.
pubmed:affiliation
Department of Biology, McMaster University, Hamilton, Ontario L8S 4A8, Canada.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't