@article{ea2df9cd14e440aeb30fe18f388b0d07,
title = "Structural basis of TRPV5 regulation by physiological and pathophysiological modulators",
abstract = "Transient receptor potential vanilloid 5 (TRPV5) is a kidney-specific Ca2+-selective ion channel that plays a key role in Ca2+ homeostasis. The basal activity of TRPV5 is balanced through activation by phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2) and inhibition by Ca2+-bound calmodulin (CaM). Parathyroid hormone (PTH), the key extrinsic regulator of Ca2+ homeostasis, increases the activity of TRPV5 via protein kinase A (PKA)-mediated phosphorylation. Metabolic acidosis leads to reduced TRPV5 activity independent of PTH, causing hypercalciuria. Using cryoelectron microscopy (cryo-EM), we show that low pH inhibits TRPV5 by precluding PI(4,5)P2 activation. We capture intermediate conformations at low pH, revealing a transition from open to closed state. In addition, we demonstrate that PI(4,5)P2 is the primary modulator of channel gating, yet PKA controls TRPV5 activity by preventing CaM binding and channel inactivation. Our data provide detailed molecular mechanisms for regulation of TRPV5 by two key extrinsic modulators, low pH and PKA.",
keywords = "CP: Molecular biology, CP: Neuroscience, CaM, PI(4,5)P, PKA, TRP channel, calmodulin, cryo-EM, cryoelectron microscopy, pH, protein kinase A, transient receptor potential channel",
author = "Fluck, {Edwin C.} and Yazici, {Aysenur Torun} and Tibor Rohacs and Moiseenkova-Bell, {Vera Y.}",
note = "Funding Information: We are grateful for the support of Sabine Baxter in managing hybridoma and cell culture at the University of Pennsylvania Perelman School of Medicine Cell Center Services Facility. We thank Dr. Ji-fang Zhang at Thomas Jefferson University for the gift of the rat calmodulin plasmid. We acknowledge the support of the Electron Microscopy Resource Lab and the Beckman Center for Cryo-Electron Microscopy at the University of Pennsylvania Perelman School of Medicine for the use of instruments. We also thank Stefan Steimle for assistance with the Krios microscope operation and data collection. We also acknowledge the use of instruments at the Electron Imaging Center for NanoMachines supported by the NIH (1S10RR23057, 1S10OD018111, and 1U24GM116792), NSF (DBI-1338135), and CNSI at UCLA. Computational resources were in part supported by NIH grant S10OD023592. This work was supported by grants from the NIH (R01GM103899, R01GM129357, and 1R35GM144120 to V.Y.M.-B. and R01GM093290 to T.R.) and by NIH training grant T32GM132039 (to E.C.F.). Conceptualization, E.C.F. and V.Y.M.-B.; methodology, E.C.F. and V.Y.M.-B.; validation, E.C.F. and A.T.Y.; formal analysis, E.C.F. and A.T.Y.; investigation, E.C.F. and A.T.Y.; writing – original draft, E.C.F. and V.Y.M.-B. writing – review & editing, E.C.F. A.T.Y. T.R. and V.Y.M.-B.; visualization, E.C.F. and A.T.Y.; funding acquisition, T.R. and V.Y.M.-B.; supervision, T.R. and V.Y.M.-B. The authors declare no competing interests. Funding Information: We are grateful for the support of Sabine Baxter in managing hybridoma and cell culture at the University of Pennsylvania Perelman School of Medicine Cell Center Services Facility . We thank Dr. Ji-fang Zhang at Thomas Jefferson University for the gift of the rat calmodulin plasmid. We acknowledge the support of the Electron Microscopy Resource Lab and the Beckman Center for Cryo-Electron Microscopy at the University of Pennsylvania Perelman School of Medicine for the use of instruments. We also thank Stefan Steimle for assistance with the Krios microscope operation and data collection. We also acknowledge the use of instruments at the Electron Imaging Center for NanoMachines supported by the NIH ( 1S10RR23057 , 1S10OD018111 , and 1U24GM116792 ), NSF ( DBI-1338135 ), and CNSI at UCLA . Computational resources were in part supported by NIH grant S10OD023592 . This work was supported by grants from the NIH ( R01GM103899 , R01GM129357 , and 1R35GM144120 to V.Y.M.-B. and R01GM093290 to T.R.) and by NIH training grant T32GM132039 (to E.C.F.). Publisher Copyright: {\textcopyright} 2022 The Authors",
year = "2022",
month = apr,
day = "26",
doi = "10.1016/j.celrep.2022.110737",
language = "English (US)",
volume = "39",
journal = "Cell Reports",
issn = "2211-1247",
publisher = "Cell Press",
number = "4",
}