1. MURC/Cavin-4 and cavin family members form tissue-specific caveolar complexes
- Author
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Bastiani, M, Liu, L, Hill, MM, Jedrychowski, MP, Nixon, SJ, Lo, HP, Abankwa, D, Luetterforst, R, Fernandez-Rojo, M, Breen, MR, Gygi, SP, Vinten, J, Walser, PJ, North, KN, Hancock, JF, Pilch, PF, Parton, RG, Bastiani, M, Liu, L, Hill, MM, Jedrychowski, MP, Nixon, SJ, Lo, HP, Abankwa, D, Luetterforst, R, Fernandez-Rojo, M, Breen, MR, Gygi, SP, Vinten, J, Walser, PJ, North, KN, Hancock, JF, Pilch, PF, and Parton, RG
- Abstract
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.
- Published
- 2009