title: Nitric oxide activates TRP channels by cysteine S-nitrosylation.
abstract: Transient receptor potential (TRP) proteins form plasma-membrane cation channels that act as sensors for diverse cellular stimuli. Here, we report a novel activation mechanism mediated by cysteine S-nitrosylation in TRP channels. Recombinant TRPC1, TRPC4, TRPC5, TRPV1, TRPV3 and TRPV4 of the TRPC and TRPV families, which are commonly classified as receptor-activated channels and thermosensor channels, induce entry of Ca(2+) into cells in response to nitric oxide (NO). Labeling and functional assays using cysteine mutants, together with membrane sidedness in activating reactive disulfides, show that cytoplasmically accessible Cys553 and nearby Cys558 are nitrosylation sites mediating NO sensitivity in TRPC5. The responsive TRP proteins have conserved cysteines on the same N-terminal side of the pore region. Notably, nitrosylation of native TRPC5 upon G protein-coupled ATP receptor stimulation elicits entry of Ca(2+) into endothelial cells. These findings reveal the structural motif for the NO-sensitive activation gate in TRP channels and indicate that NO sensors are a new functional category of cellular receptors extending over different TRP families.
authors.affiliation: Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Kyoto 615-8510, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Yoshida
authors.forename: Ryuji
authors.initials: R
authors.lastname: Inoue
authors.forename: Takashi
authors.initials: T
authors.lastname: Morii
authors.forename: Nobuaki
authors.initials: N
authors.lastname: Takahashi
authors.forename: Shinichiro
authors.initials: S
authors.lastname: Yamamoto
authors.forename: Yuji
authors.initials: Y
authors.lastname: Hara
authors.forename: Makoto
authors.initials: M
authors.lastname: Tominaga
authors.forename: Shunichi
authors.initials: S
authors.lastname: Shimizu
authors.forename: Yoji
authors.initials: Y
authors.lastname: Sato
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Mori
mesh_terms: D000818:Animals; D002118:Calcium / Q000378:metabolism; D015220:Calcium Channels / Q000378:metabolism; D002478:Cells, Cultured; D002645:Chickens; D003545:Cysteine / Q000737:chemistry / Q000378:metabolism*; D006801:Humans; D008958:Models, Molecular; D015394:Molecular Structure; D009569:Nitric Oxide / Q000378:metabolism*; D017672:Nitrogen Compounds / Q000737:chemistry / Q000378:metabolism*; D011485:Protein Binding; D012680:Sensitivity and Specificity; D015398:Signal Transduction / Q000502:physiology; D013438:Sulfhydryl Compounds / Q000737:chemistry / Q000378:metabolism; D013997:Time Factors; D050051:Transient Receptor Potential Channels / Q000378:metabolism* / Q000502:physiology
chemical_list: D015220:Calcium Channels; D017672:Nitrogen Compounds; D013438:Sulfhydryl Compounds; D050051:Transient Receptor Potential Channels; D009569:Nitric Oxide; D003545:Cysteine; D002118:Calcium