Linked Life Data

18059378

Source:http://linkedlifedata.com/resource/pubmed/id/18059378

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
12
pubmed:dateCreated
2007-12-13
pubmed:abstractText
Sphingolipids have been suggested to act as second messengers for an array of cellular signaling activities in plant cells, including stress responses and programmed cell death (PCD). However, the mechanisms underpinning these processes are not well understood. Here, we report that an Arabidopsis mutant, fumonisin B1 resistant 11-1 (fbr 11-1), which fails to generate reactive oxygen intermediates (ROIs), is incapable of initiating PCD when the mutant is challenged by fumonisin B(1) (FB(1)), a specific inhibitor of ceramide synthase. Molecular analysis indicated that FBR11 encodes a long-chain base 1 (LCB1) subunit of serine palmitoyltransferase (SPT), which catalyzes the first rate-limiting step of de novo sphingolipid synthesis. Mass spectrometric analysis of the sphingolipid concentrations revealed that whereas the fbr 11-1 mutation did not affect basal levels of sphingoid bases, the mutant showed attenuated formation of sphingoid bases in response to FB(1). By a direct feeding experiment, we show that the free sphingoid bases dihydrosphingosine, phytosphingosine and sphingosine efficiently induce ROI generation followed by cell death. Conversely, ROI generation and cell death induced by dihydrosphingosine were specifically blocked by its phosphorylated form dihydrosphingosine-1-phosphate in a dose-dependent manner, suggesting that the maintenance of homeostasis between a free sphingoid base and its phosphorylated derivative is critical to determining the cell fate. Because alterations of the sphingolipid level occur prior to the ROI production, we propose that the free sphingoid bases are involved in the control of PCD in Arabidopsis, presumably through the regulation of the ROI level upon receiving different developmental or environmental cues.
pubmed:commentsCorrections
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/Arabidopsis Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Fumonisins, http://linkedlifedata.com/resource/pubmed/chemical/LCB1 protein, Arabidopsis, http://linkedlifedata.com/resource/pubmed/chemical/Protein Subunits, http://linkedlifedata.com/resource/pubmed/chemical/Reactive Oxygen Species, http://linkedlifedata.com/resource/pubmed/chemical/Serine C-Palmitoyltransferase, http://linkedlifedata.com/resource/pubmed/chemical/Sphingolipids, http://linkedlifedata.com/resource/pubmed/chemical/Sphingosine, http://linkedlifedata.com/resource/pubmed/chemical/dihydrosphingosine 1-phosphate, http://linkedlifedata.com/resource/pubmed/chemical/fumonisin B1, http://linkedlifedata.com/resource/pubmed/chemical/phytosphingosine, http://linkedlifedata.com/resource/pubmed/chemical/safingol
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
1748-7838
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
17
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1030-40
pubmed:dateRevised
2008-4-14
pubmed:meshHeading
pubmed:year
2007
pubmed:articleTitle
Involvement of sphingoid bases in mediating reactive oxygen intermediate production and programmed cell death in Arabidopsis.
pubmed:affiliation
National Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Datun Road, Beijing 100101, China.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't