MURC/Cavin-4 and cavin family members form tissue-specific caveolar complexes.
Polymerase I and transcript release factor (PTRF)/Cavin is a cytoplasmic protein whose expression is obligatory for caveola formation. Using biochemistry and fluorescence resonance energy transfer-based approaches, we now show that a family of related proteins, PTRF/Cavin-1, serum deprivation response (SDR)/Cavin-2, SDR-related gene product that binds to C kinase (SRBC)/Cavin-3, and muscle-restricted coiled-coil protein (MURC)/Cavin-4, forms a multiprotein complex that associates with caveolae. This complex can constitutively assemble in the cytosol and associate with caveolin at plasma membrane caveolae. Cavin-1, but not other cavins, can induce caveola formation in a heterologous system and is required for the recruitment of the cavin complex to caveolae. The tissue-restricted expression of cavins suggests that caveolae may perform tissue-specific functions regulated by the composition of the cavin complex. Cavin-4 is expressed predominantly in muscle, and its distribution is perturbed in human muscle disease associated with Caveolin-3 dysfunction, identifying Cavin-4 as a novel muscle disease candidate caveolar protein.
Bastiani
Michele
M
Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland 4072, Australia.
Liu
Libin
L
Hill
Michelle M
MM
Jedrychowski
Mark P
MP
Nixon
Susan J
SJ
Lo
Harriet P
HP
Abankwa
Daniel
D
Luetterforst
Robert
R
Fernandez-Rojo
Manuel
M
Breen
Michael R
MR
Gygi
Steven P
SP
Vinten
Jorgen
J
Walser
Piers J
PJ
North
Kathryn N
KN
Hancock
John F
JF
Pilch
Paul F
PF
Parton
Robert G
RG
D041721:3T3-L1 Cells / Q000378:metabolism / Q000648:ultrastructure; D000595:Amino Acid Sequence; D000818:Animals; D021941:Caveolae / Q000378:metabolism / Q000648:ultrastructure; D022461:Caveolins / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D008565:Membrane Proteins / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D018345:Mice, Knockout; D008969:Molecular Sequence Data; D046912:Multiprotein Complexes / Q000378:metabolism*; D009124:Muscle Proteins / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D009135:Muscular Diseases / Q000378:metabolism / Q000473:pathology; D010802:Phylogeny; D020033:Protein Isoforms / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D016601:RNA-Binding Proteins; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D012508:Sarcolemma / Q000378:metabolism / Q000648:ultrastructure; D016415:Sequence Alignment
D022461:Caveolins; C112745:Cavin1 protein, mouse; D008565:Membrane Proteins; D046912:Multiprotein Complexes; D009124:Muscle Proteins; D020033:Protein Isoforms; D016601:RNA-Binding Proteins; D011993:Recombinant Fusion Proteins