Letter abstract
Nature Cell Biology 7, 179 - 185 (2005)
Published online: 23 January 2005 | doi:10.1038/ncb1218
TRPC1 forms the stretch-activated cation channel in vertebrate cells
Rosario Maroto1, Albert Raso2, Thomas G. Wood3, Alex Kurosky3, Boris Martinac2 & Owen P. Hamill1
The mechanosensitive cation channel (MscCa) transduces membrane stretch into cation (Na+, K+, Ca2+ and Mg2+) flux across the cell membrane, and is implicated in cell-volume regulation1, cell locomotion2, muscle dystrophy3 and cardiac arrhythmias4. However, the membrane protein(s) that form the MscCa in vertebrates remain unknown. Here, we use an identification strategy that is based on detergent solubilization of frog oocyte membrane proteins, followed by liposome reconstitution and evaluation by patch-clamp5. The oocyte was chosen because it expresses the prototypical
MscCa (
107MscCa/oocyte)6 that is preserved in cytoskeleton-deficient membrane vesicles7. We identified a membrane-protein fraction that reconstituted high MscCa activity and showed an abundance of a protein that had a relative molecular mass of 80,000 (Mr 80K). This protein was identified, by immunological techniques, as the canonical transient receptor potential channel 1 (TRPC1)8, 9, 10. Heterologous expression of the human TRPC1 resulted in a >1,000% increase in MscCa patch density, whereas injection of a TRPC1-specific antisense RNA abolished endogenous MscCa activity. Transfection of human TRPC1 into CHO-K1 cells also significantly increased MscCa expression. These observations indicate that TRPC1 is a component of the vertebrate MscCa, which is gated by tension developed in the lipid bilayer, as is the case in various prokaryotic mechanosensitive (Ms) channels11.
- Department of Neuroscience & Cell Biology, UTMB, Galveston, TX 77555, USA.
- School of Medicine and Pharmacology, University of Western Australia, Crawley, WA 6009, Australia.
- Department of Human Biological Chemistry & Genetics, UTMB, Galveston, TX 77555, USA.
Correspondence to: Owen P. Hamill1 e-mail: ohamill@utmb.edu
MORE ARTICLES LIKE THIS
These links to content published by NPG are automatically generated.
RESEARCH
G q -coupled receptors as mechanosensors mediating myogenic vasoconstrictionThe EMBO Journal Article (03 Dec 2008)
Magnesium permeation through mechanosensitive channels: single-current measurementsCell Research Original Article
A large-conductance mechanosensitive channel in E. coli encoded by mscL aloneNature Letters to Editor (17 Mar 1994)
See all 67 matches for Research
