caveolin-1 (CAV1, CAV)

Function

• may act as a scaffolding protein within caveolar membranes
• interacts directly with G-protein alpha subunits & can functionally regulate their activity (putative)
• role in costimulatory signal essential for T-cell receptor (TCR)- mediated T-cell activation
• binding to DPP4 induces T-cell proliferation & NF-kappa-B activation (T-cell receptor/CD3-dependent)
• interacts with GLIPR2, NOSTRIN, SNAP25 & syntaxin
• interacts with rotavirus A NSP4
• interacts (via the N-terminus) with DPP4

Structure

• initiator Met for isoform beta is removed during or just after translation; the new N-terminal amino acid is then N-acetylated
• homooligomer
• belongs to the caveolin family

Compartment

• Golgi membrane
• cell membrane
• caveola
• membrane raft
• colocalized with DPP4 in membrane rafts
• potential hairpin- like structure in the membrane
• membrane protein of caveolae

Alternative initiation

• named isoforms=2; alpha, beta
• initiator Met-1 is removed
• contains a N-acetylalanine at position 2

Expression

• expressed in muscle & lung
• lower expression in liver, brain & kidney

Pathology

• defects in CAV1 are the cause of congenital generalized lipodystrophy type 3

Notes

• 1st structural component of caveolae identified
• when integrated into the microenvironment of a lipid raft, a caveola develops.

More general terms

• caveolin
• phosphoprotein

Database

• Entrez gene: http://www.ncbi.nlm.nih.gov/sites/entrez?db=gene&cmd=Retrieve&dopt=Graphics&list_uids=857
• Kegg: http://www.genome.jp/dbget-bin/www_bget?hsa:857
• OMIM: https://mirror.omim.org/entry/601047
• OMIM: https://mirror.omim.org/entry/612526
• UniProt: http://www.uniprot.org/uniprot/Q03135.html