Linked Life Data

11006294

Source:http://linkedlifedata.com/resource/pubmed/id/11006294

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
50
pubmed:dateCreated
2001-1-8
pubmed:abstractText
Sphingolipids have emerged as novel bioactive mediators in eukaryotic cells including yeast. It has been proposed that sphingomyelin (SM) hydrolysis and the concomitant generation of ceramide are involved in various stress responses in mammalian cells. The yeast Saccharomyces cerevisiae has inositol phosphosphingolipids (IPS) instead of SM and glycolipids, and synthesis of IPS is indispensable to its growth. Although the genes responsible for the synthesis of IPS have been identified, the gene(s) for the degradation of IPS has not been reported. Here we show that ISC1 (YER019w), which has homology to bacterial neutral sphingomyelinase (SMase), encodes IPS phospholipase C (IPS-PLC). First, we observed that overexpression of ISC1 greatly increased neutral SMase activity, and this activity was dependent on the presence of phosphatidylserine. Cells deleted in ISC1 demonstrated negligible neutral SMase activity. Because yeast cells have IPS instead of SM, we investigated whether IPS are the physiologic substrates of this enzyme. Lysates of ISC1-overexpressing cells demonstrated very high PLC activities on IPS. Deletion of ISC1 eliminated endogenous IPS-PLC activities. Labeling yeast cells with [(3)H]dihydrosphingosine showed that IPS were increased in the deletion mutant cells. This study identifies the first enzyme involved in catabolism of complex sphingolipids in S. cerevisiae.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
275
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
39793-8
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed-meshheading:11006294-Blotting, Western, pubmed-meshheading:11006294-Cations, pubmed-meshheading:11006294-Detergents, pubmed-meshheading:11006294-Dose-Response Relationship, Drug, pubmed-meshheading:11006294-Electrophoresis, Polyacrylamide Gel, pubmed-meshheading:11006294-Gene Deletion, pubmed-meshheading:11006294-Hydrogen-Ion Concentration, pubmed-meshheading:11006294-Hydrolysis, pubmed-meshheading:11006294-Kinetics, pubmed-meshheading:11006294-Octoxynol, pubmed-meshheading:11006294-Phosphatidylserines, pubmed-meshheading:11006294-Phospholipases, pubmed-meshheading:11006294-Plasmids, pubmed-meshheading:11006294-Saccharomyces cerevisiae, pubmed-meshheading:11006294-Saccharomyces cerevisiae Proteins, pubmed-meshheading:11006294-Sphingolipids, pubmed-meshheading:11006294-Sphingomyelin Phosphodiesterase, pubmed-meshheading:11006294-Transfection, pubmed-meshheading:11006294-Type C Phospholipases
pubmed:year
2000
pubmed:articleTitle
Identification of ISC1 (YER019w) as inositol phosphosphingolipid phospholipase C in Saccharomyces cerevisiae.
pubmed:affiliation
Department of Biochemistry and Molecular Biology and the Ralph H. Johnson Veterans Administration Hospital and the Department of Medicine, Medical University of South Carolina, Charleston 29425, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't