Molecular Determinants of the Sensitivity to Gq/11-Phospholipase C-dependent Gating, Gd3+ Potentiation, and Ca2+ Permeability in the Transient Receptor Potential Canonical Type 5 (TRPC5) Channel
dc.contributor.author | Chen, Xingjuan | |
dc.contributor.author | Li, Wennan | |
dc.contributor.author | Riley, Ashley M. | |
dc.contributor.author | Soliman, Mario | |
dc.contributor.author | Chakraborty, Saikat Chakrabort | |
dc.contributor.author | Stamatkin, Christopher W. | |
dc.contributor.author | Obukhov, Alexander G. | |
dc.contributor.department | Cellular and Integrative Physiology, School of Medicine | en_US |
dc.date.accessioned | 2018-05-31T14:03:11Z | |
dc.date.available | 2018-05-31T14:03:11Z | |
dc.date.issued | 2017-01-20 | |
dc.description.abstract | Transient receptor potential canonical type 5 (TRPC5) is a Ca2+-permeable cation channel that is highly expressed in the brain and is implicated in motor coordination, innate fear behavior, and seizure genesis. The channel is activated by a signal downstream of the G-protein-coupled receptor (GPCR)-Gq/11-phospholipase C (PLC) pathway. In this study we aimed to identify the molecular mechanisms involved in regulating TRPC5 activity. We report that Arg-593, a residue located in the E4 loop near the TRPC5 extracellular Gd3+ binding site, is critical for conferring the sensitivity to GPCR-Gq/11-PLC-dependent gating on TRPC5. Indeed, guanosine 5'-O-(thiotriphosphate) and GPCR agonists only weakly activate the TRPC5R593A mutant, whereas the addition of Gd3+ rescues the mutant's sensitivity to GPCR-Gq/11-PLC-dependent gating. Computer modeling suggests that Arg-593 may cross-bridge the E3 and E4 loops, forming the "molecular fulcrum." While validating the model using site-directed mutagenesis, we found that the Tyr-542 residue is critical for establishing a functional Gd3+ binding site, the Tyr-541 residue participates in fine-tuning Gd3+-sensitivity, and that the Asn-584 residue determines Ca2+ permeability of the TRPC5 channel. This is the first report providing molecular insights into the molecular mechanisms regulating the sensitivity to GPCR-Gq/11-PLC-dependent gating of a receptor-operated channel. | en_US |
dc.eprint.version | Final published version | en_US |
dc.identifier.citation | Chen, X., Li, W., Riley, A. M., Soliman, M., Chakraborty, S., Stamatkin, C. W., & Obukhov, A. G. (2017). Molecular Determinants of the Sensitivity to Gq/11-Phospholipase C-dependent Gating, Gd3+ Potentiation, and Ca2+ Permeability in the Transient Receptor Potential Canonical Type 5 (TRPC5) Channel. The Journal of Biological Chemistry, 292(3), 898–911. http://doi.org/10.1074/jbc.M116.755470 | en_US |
dc.identifier.uri | https://hdl.handle.net/1805/16310 | |
dc.language.iso | en_US | en_US |
dc.publisher | American Society for Biochemistry and Molecular Biology | en_US |
dc.relation.isversionof | 10.1074/jbc.M116.755470 | en_US |
dc.relation.journal | Journal of Biological Chemistry | en_US |
dc.rights | Publisher Policy | en_US |
dc.source | PMC | en_US |
dc.subject | G-protein-coupled receptor (GPCR) | en_US |
dc.subject | Calcium | en_US |
dc.subject | Ion channel | en_US |
dc.subject | Patch clamp | en_US |
dc.subject | Transient receptor potential channels (TRP channels) | en_US |
dc.title | Molecular Determinants of the Sensitivity to Gq/11-Phospholipase C-dependent Gating, Gd3+ Potentiation, and Ca2+ Permeability in the Transient Receptor Potential Canonical Type 5 (TRPC5) Channel | en_US |
dc.type | Article | en_US |