@article{aa3f070346a646f596d117fa72ad2b0f,
title = "Structural and Biophysical Analysis of the CLCA1 VWA Domain Suggests Mode of TMEM16A Engagement",
abstract = "The secreted protein calcium-activated chloride channel regulator 1 (CLCA1) utilizes a von Willebrand factor type A (VWA) domain to bind to and potentiate the calcium-activated chloride channel TMEM16A. To gain insight into this unique potentiation mechanism, we determined the 2.0-{\AA} crystal structure of human CLCA1 VWA bound to Ca2+. The structure reveals the metal-ion-dependent adhesion site (MIDAS) in a high-affinity “open” conformation, engaging in crystal contacts that likely mimic how CLCA1 engages TMEM16A. The CLCA1 VWA contains a disulfide bond between α3 and α4 in close proximity to the MIDAS that is invariant in the CLCA family and unique in VWA structures. Further biophysical studies indicate that CLCA1 VWA is preferably stabilized by Mg2+ over Ca2+ and that α6 atypically extends from the VWA core. Finally, an analysis of TMEM16A structures suggests residues likely to mediate interaction with CLCA1 VWA.",
keywords = "CLCA, CLCA1, MIDAS, SAXS, TMEM16A, VWA, airway disease, calcium-activated chloride channel, calcium-activated chloride channel regulator, calcium-activated chloride channel regulator 1, crystal structure, cystic fibrosis, metal-ion-dependent adhesion site motif, small-angle X-ray scattering, von Willebrand factor A domain",
author = "Berry, {Kayla N.} and Brett, {Tom J.}",
note = "Funding Information: This work was supported by NIH R01-HL119813 (to T.J.B.), NIH UL1TR002345 (pilot to T.J.B.), CIMED Pilot and Feasibility Grant (to T.J.B.), Cystic Fibrosis Foundation BRETT-G018 (to T.J.B.), NIH F30-HL140783 (to K.N.B.), NIH T32-HL007317 (to K.N.B.), and T32-GM007200 (to K.N.B.). Results were derived from work performed at the Advanced Light Source, Berkeley, CA (ALS), beamline 4.2.2 (The Molecular Biology Consortium), and the SYBILS HT-SAX beamline 12.3.1. ALS is supported by the Office of Basic Energy Sciences of the U.S. DOE (DE-AC02-05CH11231), the Integrated Diffraction Analysis Technologies (IDAT) program, and supported by DOE Office of Biological and Environmental Research. Additional support comes from the NIH project ALS-ENABLE (P30 GM124169) and a High-End Instrumentation Grant, S10OD018483. We thank Prof. Greg R. Bowman for use of the Chirascan CD spectrophotomer and Catherine R. Knoverek for technical assistance with CD experiments. K.N.B. executed experiments. K.N.B. and T.J.B. planned experiments, analyzed results, and wrote the manuscript. The authors declare no conflicts of interest. Funding Information: This work was supported by NIH R01-HL119813 (to T.J.B.), NIH UL1TR002345 (pilot to T.J.B.), CIMED Pilot and Feasibility Grant (to T.J.B.), Cystic Fibrosis Foundation BRETT-G018 (to T.J.B.), NIH F30-HL140783 (to K.N.B.), NIH T32-HL007317 (to K.N.B.), and T32-GM007200 (to K.N.B.). Results were derived from work performed at the Advanced Light Source, Berkeley, CA (ALS), beamline 4.2.2 (The Molecular Biology Consortium), and the SYBILS HT-SAX beamline 12.3.1. ALS is supported by the Office of Basic Energy Sciences of the U.S. DOE ( DE-AC02-05CH11231 ), the Integrated Diffraction Analysis Technologies (IDAT) program, and supported by DOE Office of Biological and Environmental Research . Additional support comes from the NIH project ALS-ENABLE ( P30 GM124169 ) and a High-End Instrumentation Grant , S10OD018483 . We thank Prof. Greg R. Bowman for use of the Chirascan CD spectrophotomer and Catherine R. Knoverek for technical assistance with CD experiments. Publisher Copyright: {\textcopyright} 2019 The Authors",
year = "2020",
month = jan,
day = "28",
doi = "10.1016/j.celrep.2019.12.059",
language = "English",
volume = "30",
pages = "1141--1151.e3",
journal = "Cell Reports",
issn = "2211-1247",
number = "4",
}