PTRF-Cavin, a conserved cytoplasmic protein required for caveola formation and function.
Caveolae are abundant cell-surface organelles involved in lipid regulation and endocytosis. We used comparative proteomics to identify PTRF (also called Cav-p60, Cavin) as a putative caveolar coat protein. PTRF-Cavin selectively associates with mature caveolae at the plasma membrane but not Golgi-localized caveolin. In prostate cancer PC3 cells, and during development of zebrafish notochord, lack of PTRF-Cavin expression correlates with lack of caveolae, and caveolin resides on flat plasma membrane. Expression of PTRF-Cavin in PC3 cells is sufficient to cause formation of caveolae. Knockdown of PTRF-Cavin reduces caveolae density, both in mammalian cells and in the zebrafish. Caveolin remains on the plasma membrane in PTRF-Cavin knockdown cells but exhibits increased lateral mobility and accelerated lysosomal degradation. We conclude that PTRF-Cavin is required for caveola formation and sequestration of mobile caveolin into immobile caveolae.
Hill
Michelle M
MM
Institute for Molecular Bioscience, University of Queensland, Brisbane, Queensland 4072, Australia.
Bastiani
Michele
M
Luetterforst
Robert
R
Kirkham
Matthew
M
Kirkham
Annika
A
Nixon
Susan J
SJ
Walser
Piers
P
Abankwa
Daniel
D
Oorschot
Viola M J
VM
Martin
Sally
S
Hancock
John F
JF
Parton
Robert G
RG
D000818:Animals; D001516:Bees; D021941:Caveolae / Q000378:metabolism* / Q000648:ultrastructure; D051242:Caveolin 1 / Q000378:metabolism; D002460:Cell Line; D045744:Cell Line, Tumor; D002462:Cell Membrane / Q000378:metabolism* / Q000648:ultrastructure; D002478:Cells, Cultured; D017124:Conserved Sequence; D006224:Cricetinae; D003593:Cytoplasm / Q000378:metabolism* / Q000648:ultrastructure; D019143:Evolution, Molecular; D005347:Fibroblasts; D006056:Golgi Apparatus / Q000378:metabolism / Q000648:ultrastructure; D007425:Intracellular Membranes / Q000378:metabolism / Q000648:ultrastructure; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D018345:Mice, Knockout; D008969:Molecular Sequence Data; D041681:NIH 3T3 Cells; D009672:Notochord / Q000196:embryology / Q000378:metabolism / Q000648:ultrastructure; D016601:RNA-Binding Proteins; D013045:Species Specificity; D015027:Zebrafish
D051242:Caveolin 1; C112745:Cavin1 protein, mouse; D008565:Membrane Proteins; D016601:RNA-Binding Proteins