X-Ray Crystal Structure of a TRPM Assembly Domain Reveals An Antiparallel Four-Stranded Coiled-Coil
Transient receptor potential (TRP) channels comprise a large family of tetrameric cation-selective ion channels that respond to diverse forms of sensory input. Earlier studies showed that members of the TRPM subclass possess a self-assembling tetrameric C-terminal cytoplasmic coiled-coil domain that underlies channel assembly and trafficking. Here, we present the high-resolution crystal structure of the coiled-coil domain of the channel enzyme TRPM7. The crystal structure, together with biochemical experiments, reveals an unexpected four-stranded antiparallel coiled-coil architecture that bears unique features relative to other antiparallel coiled-coils. Structural analysis indicates that a limited set of interactions encode assembly specificity determinants and uncovers a previously unnoticed segregation of TRPM assembly domains into two families that correspond with the phylogenetic divisions seen for the complete subunits. Together, the data provide a framework for understanding the mechanism of TRPM channel assembly and highlight the diversity of forms found in the coiled-coil fold.
- Research Organization:
- SLAC National Accelerator Lab., Menlo Park, CA (United States)
- Sponsoring Organization:
- USDOE
- DOE Contract Number:
- AC02-76SF00515
- OSTI ID:
- 953152
- Report Number(s):
- SLAC-REPRINT-2009-132; JMOBAK; TRN: US200914%%350
- Journal Information:
- J. Mol. Biol. 383:854,2008, Vol. 383, Issue 4; ISSN 0022-2836
- Country of Publication:
- United States
- Language:
- English
Similar Records
Conformational Specificity of the Lac Repressor Coiled-Coil Tetramerization Domain
A switch from parallel to antiparallel strand orientation in a coiled-coil X-ray structure via two core hydrophobic mutations