Linked Life Data

11777922

Source:http://linkedlifedata.com/resource/pubmed/id/11777922

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
11
pubmed:dateCreated
2002-3-11
pubmed:abstractText
SNAP receptor (SNARE) proteins function in intracellular trafficking by forming complexes that bridge vesicle and target membranes prior to fusion. Biochemical studies indicate that the entry of certain SNARE proteins into complexes is inhibited by intramolecular interactions that generate a closed conformation. For example, an essential N-terminal regulatory domain of the yeast plasma membrane SNARE Sso1p sequesters the C-terminal SNARE motif and prevents it from binding to its assembly partners Sec9p and Sncp. Here, we introduce mutations into Sso1p that cause it to remain constitutively open. These open mutants can functionally substitute for wild-type Sso1p protein in vivo, demonstrating that inhibition of SNARE assembly is not the essential function of the N-terminal regulatory domain. Furthermore, the open mutants suppress sec9--4, a mutation that causes a severe defect in SNARE assembly. Elevated levels of SNARE complexes are observed in cells expressing the open mutants. In the presence of sufficient Sec9p, these complexes accumulate to levels that cause severe growth defects. Similarly, overexpression of the open mutants in yeast carrying mutations in the SNARE disassembly machinery impairs growth. Our findings indicate that elevated levels of SNARE complexes can be toxic and that these levels are normally controlled by the SNARE disassembly machinery, by the limited availability of Sec9p, and by the closed conformation of Sso1p.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
277
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
9375-81
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2002
pubmed:articleTitle
Conformational regulation of SNARE assembly and disassembly in vivo.
pubmed:affiliation
Department of Molecular Biology, Princeton University, Princeton, New Jersey 08544, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.