Linked Life Data

7744760

Source:http://linkedlifedata.com/resource/pubmed/id/7744760

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
19
pubmed:dateCreated
1995-6-15
pubmed:abstractText
Small GTPases of the Rab family are key regulators of intracellular transport. They are associated with the cytoplasmic surface of distinct exocytic and endocytic organelles and with transport vesicles connecting these compartments. Rab proteins are also present in the cytosol in the GDP-bound conformation complexed to Rab GDP dissociation inhibitor (RabGDI). Upon membrane association, RabGDI is released, and the Rab protein is converted into the GTP-bound form. In this paper we have investigated whether Rab5, which regulates the clathrin-coated vesicle-mediated pathway of endocytosis, can directly associate with the membrane of clathrin-coated vesicles (CCV) purified from bovine brain in vitro. We found that RabGDI can specifically deliver Rab5 but not Rab7, which is localized to late endosomes, to CCV. Furthermore, CCV contain a heat- and trypsin-sensitive activity that stimulates the dissociation of GDP from Rab5, but not from Rab7, and the subsequent binding of GTP. The activity was found to be associated with the CCV membrane but not with the coat components. CCV weakly stimulated GDP release from either post-translationally modified or unmodified Rab5 alone. However, maximal GDP dissociation stimulation required the presence of RabGDI, suggesting that the factor(s) responsible for the membrane association and GDP/GTP exchange of Rab5 recognize the protein complexed to RabGDI. These data demonstrate that CCV are competent for acquiring Rab5 and for converting the molecule into the GTP-bound active form.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
12
pubmed:volume
270
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
11257-62
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
1995
pubmed:articleTitle
A GDP/GTP exchange-stimulatory activity for the Rab5-RabGDI complex on clathrin-coated vesicles from bovine brain.
pubmed:affiliation
European Molecular Biology Laboratory, Heidelberg, Federal Republic of Germany.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't