Linked Life Data

9020162

Source:http://linkedlifedata.com/resource/pubmed/id/9020162

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
7
pubmed:dateCreated
1997-3-14
pubmed:abstractText
Caveolin is a principal structural component of caveolae membranes in vivo. Recently, a family of caveolin-related proteins has been identified; caveolin has been retermed caveolin-1. Caveolin family members share three characteristic properties: (i) detergent insolubility at low temperatures; (ii) self-oligomerization; and (iii) incorporation into low density Triton-insoluble fractions enriched in caveolae membranes. Here, we have used a deletion mutagenesis approach as a first step toward understanding which regions of caveolin-1 contribute to its unusual properties. Two caveolin-1 deletion mutants were created that lack either the C-terminal domain (Cav-1DeltaC) or the N-terminal domain (Cav-1DeltaN); these mutants were compared with the behavior of full-length caveolin-1 (Cav-1FL) expressed in parallel. Our results show that the N-terminal domain and membrane spanning segment are sufficient to form high molecular mass oligomers of caveolin-1. However, a complete caveolin-1 molecule is required for conveying detergent insolubility and incorporation into low density Triton-insoluble complexes. These data indicate that homo-oligomerization and an intact transmembrane are not sufficient to confer detergent insolubility, suggesting an unknown role for the C-terminal domain in this process. To better understand the role of the C-terminal domain, this region of caveolin-1 (residues 135-178) was expressed as a glutathione S-transferase fusion protein in Escherichia coli. Purified recombinant glutathione S-transferase-C-Cav-1 was found to stably interact with full-length caveolin-1 but not with the two caveolin-1 deletion mutants. These results suggest that the C-terminal domain interacts with both the N-terminal and C-terminal domains of an adjacent caveolin-1 homo-oligomer. This appears to be a specific homo-typic interaction, because the C-terminal domain of caveolin-1 failed to interact with full-length forms of caveolin-2 and caveolin-3. Homo-typic interaction of the C-terminal domain with an adjacent homo-oligomer could provide a mechanism for clustering caveolin-1 homo-oligomers while excluding other caveolin family members. This type of lateral segregation event could promote caveolae membrane formation and contribute to the detergent insolubility of caveolins-1, -2, and -3.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
14
pubmed:volume
272
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
4398-403
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1997
pubmed:articleTitle
Mutational analysis of the properties of caveolin-1. A novel role for the C-terminal domain in mediating homo-typic caveolin-caveolin interactions.
pubmed:affiliation
Whitehead Institute for Biomedical Research, Cambridge, Massachusetts 02142-1479, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't