Linked Life Data

19801664

Source:http://linkedlifedata.com/resource/pubmed/id/19801664

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
49
pubmed:dateCreated
2009-11-30
pubmed:abstractText
Fatty acid amide hydrolase (FAAH) terminates the endocannabinoid signaling pathway that regulates numerous neurobehavioral processes in animals by hydrolyzing N-acylethanolamines (NAEs). Recently, an Arabidopsis FAAH homologue (AtFAAH) was identified, and several studies, especially those using AtFAAH overexpressing and knock-out lines, have suggested an in vivo role for FAAH in the catabolism of NAEs in plants. We previously reported that overexpression of AtFAAH in Arabidopsis resulted in accelerated seedling growth, and in seedlings that were insensitive to exogenous NAEs but hypersensitive to abscisic acid (ABA) and hypersusceptible to nonhost pathogens. Here we show that whereas the enhanced growth and NAE tolerance of the AtFAAH overexpressing seedlings depend on the catalytic activity of AtFAAH, hypersensitivity to ABA and hypersusceptibility to nonhost pathogens are independent of its enzymatic activity. Five amino acids known to be critical for rat FAAH activity are also conserved in AtFAAH (Lys-205, Ser-281, Ser-282, Ser-305, and Arg-307). Site-directed mutation of each of these conserved residues in AtFAAH abolished its hydrolytic activity when expressed in Escherichia coli, supporting a common catalytic mechanism in animal and plant FAAH enzymes. Overexpression of these inactive AtFAAH mutants in Arabidopsis showed no growth enhancement and no NAE tolerance, but still rendered the seedlings hypersensitive to ABA and hypersusceptible to nonhost pathogens to a degree similar to the overexpression of the native AtFAAH. Taken together, our findings suggest that the AtFAAH influences plant growth and interacts with ABA signaling and plant defense through distinctly different mechanisms.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
1083-351X
pubmed:author
pubmed:issnType
Electronic
pubmed:day
4
pubmed:volume
284
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
34065-74
pubmed:dateRevised
2011-3-3
pubmed:meshHeading
pubmed:year
2009
pubmed:articleTitle
Mutations in Arabidopsis fatty acid amide hydrolase reveal that catalytic activity influences growth but not sensitivity to abscisic acid or pathogens.
pubmed:affiliation
Department of Biological Sciences, Center for Plant Lipid Research, University of North Texas, Denton, Texas 76203, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, Non-P.H.S., Research Support, Non-U.S. Gov't