LRRC8 Proteins Form Volume-Regulated Anion Channels that Sense Ionic Strength

Ruhma Syeda, Zhaozhu Qiu, Adrienne E. Dubin, Swetha E. Murthy, Maria N. Florendo, Daniel E. Mason, Jayanti Mathur, Stuart M. Cahalan, Eric C. Peters, Mauricio Montal, Ardem Patapoutian

Research output: Contribution to journalArticle

83 Citations (Scopus)

Abstract

Summary The volume-regulated anion channel (VRAC) is activated when a cell swells, and it plays a central role in maintaining cell volume in response to osmotic challenges. SWELL1 (LRRC8A) was recently identified as an essential component of VRAC. However, the identity of the pore-forming subunits of VRAC and how the channel is gated by cell swelling are unknown. Here, we show that SWELL1 and up to four other LRRC8 subunits assemble into heterogeneous complexes of ∼800 kDa. When reconstituted into bilayers, LRRC8 complexes are sufficient to form anion channels activated by osmolality gradients. In bilayers, as well as in cells, the single-channel conductance of the complexes depends on the LRRC8 composition. Finally, low ionic strength (Γ) in the absence of an osmotic gradient activates the complexes in bilayers. These data demonstrate that LRRC8 proteins together constitute the VRAC pore and that hypotonic stress can activate VRAC through a decrease in cytoplasmic Γ.

Original languageEnglish (US)
Pages (from-to)499-511
Number of pages13
JournalCell
Volume164
Issue number3
DOIs
StatePublished - Jan 28 2016

Fingerprint

Ionic strength
Osmolar Concentration
Anions
Proteins
Osmotic Pressure
Cell Size
Swelling
Chemical analysis

ASJC Scopus subject areas

  • Biochemistry, Genetics and Molecular Biology(all)

Cite this

Syeda, R., Qiu, Z., Dubin, A. E., Murthy, S. E., Florendo, M. N., Mason, D. E., ... Patapoutian, A. (2016). LRRC8 Proteins Form Volume-Regulated Anion Channels that Sense Ionic Strength. Cell, 164(3), 499-511. https://doi.org/10.1016/j.cell.2015.12.031

LRRC8 Proteins Form Volume-Regulated Anion Channels that Sense Ionic Strength. / Syeda, Ruhma; Qiu, Zhaozhu; Dubin, Adrienne E.; Murthy, Swetha E.; Florendo, Maria N.; Mason, Daniel E.; Mathur, Jayanti; Cahalan, Stuart M.; Peters, Eric C.; Montal, Mauricio; Patapoutian, Ardem.

In: Cell, Vol. 164, No. 3, 28.01.2016, p. 499-511.

Research output: Contribution to journalArticle

Syeda, R, Qiu, Z, Dubin, AE, Murthy, SE, Florendo, MN, Mason, DE, Mathur, J, Cahalan, SM, Peters, EC, Montal, M & Patapoutian, A 2016, 'LRRC8 Proteins Form Volume-Regulated Anion Channels that Sense Ionic Strength', Cell, vol. 164, no. 3, pp. 499-511. https://doi.org/10.1016/j.cell.2015.12.031
Syeda R, Qiu Z, Dubin AE, Murthy SE, Florendo MN, Mason DE et al. LRRC8 Proteins Form Volume-Regulated Anion Channels that Sense Ionic Strength. Cell. 2016 Jan 28;164(3):499-511. https://doi.org/10.1016/j.cell.2015.12.031
Syeda, Ruhma ; Qiu, Zhaozhu ; Dubin, Adrienne E. ; Murthy, Swetha E. ; Florendo, Maria N. ; Mason, Daniel E. ; Mathur, Jayanti ; Cahalan, Stuart M. ; Peters, Eric C. ; Montal, Mauricio ; Patapoutian, Ardem. / LRRC8 Proteins Form Volume-Regulated Anion Channels that Sense Ionic Strength. In: Cell. 2016 ; Vol. 164, No. 3. pp. 499-511.
@article{ceaac54c0b7e4ce38329573075a08bca,
title = "LRRC8 Proteins Form Volume-Regulated Anion Channels that Sense Ionic Strength",
abstract = "Summary The volume-regulated anion channel (VRAC) is activated when a cell swells, and it plays a central role in maintaining cell volume in response to osmotic challenges. SWELL1 (LRRC8A) was recently identified as an essential component of VRAC. However, the identity of the pore-forming subunits of VRAC and how the channel is gated by cell swelling are unknown. Here, we show that SWELL1 and up to four other LRRC8 subunits assemble into heterogeneous complexes of ∼800 kDa. When reconstituted into bilayers, LRRC8 complexes are sufficient to form anion channels activated by osmolality gradients. In bilayers, as well as in cells, the single-channel conductance of the complexes depends on the LRRC8 composition. Finally, low ionic strength (Γ) in the absence of an osmotic gradient activates the complexes in bilayers. These data demonstrate that LRRC8 proteins together constitute the VRAC pore and that hypotonic stress can activate VRAC through a decrease in cytoplasmic Γ.",
author = "Ruhma Syeda and Zhaozhu Qiu and Dubin, {Adrienne E.} and Murthy, {Swetha E.} and Florendo, {Maria N.} and Mason, {Daniel E.} and Jayanti Mathur and Cahalan, {Stuart M.} and Peters, {Eric C.} and Mauricio Montal and Ardem Patapoutian",
year = "2016",
month = "1",
day = "28",
doi = "10.1016/j.cell.2015.12.031",
language = "English (US)",
volume = "164",
pages = "499--511",
journal = "Cell",
issn = "0092-8674",
publisher = "Cell Press",
number = "3",

}

TY - JOUR

T1 - LRRC8 Proteins Form Volume-Regulated Anion Channels that Sense Ionic Strength

AU - Syeda, Ruhma

AU - Qiu, Zhaozhu

AU - Dubin, Adrienne E.

AU - Murthy, Swetha E.

AU - Florendo, Maria N.

AU - Mason, Daniel E.

AU - Mathur, Jayanti

AU - Cahalan, Stuart M.

AU - Peters, Eric C.

AU - Montal, Mauricio

AU - Patapoutian, Ardem

PY - 2016/1/28

Y1 - 2016/1/28

N2 - Summary The volume-regulated anion channel (VRAC) is activated when a cell swells, and it plays a central role in maintaining cell volume in response to osmotic challenges. SWELL1 (LRRC8A) was recently identified as an essential component of VRAC. However, the identity of the pore-forming subunits of VRAC and how the channel is gated by cell swelling are unknown. Here, we show that SWELL1 and up to four other LRRC8 subunits assemble into heterogeneous complexes of ∼800 kDa. When reconstituted into bilayers, LRRC8 complexes are sufficient to form anion channels activated by osmolality gradients. In bilayers, as well as in cells, the single-channel conductance of the complexes depends on the LRRC8 composition. Finally, low ionic strength (Γ) in the absence of an osmotic gradient activates the complexes in bilayers. These data demonstrate that LRRC8 proteins together constitute the VRAC pore and that hypotonic stress can activate VRAC through a decrease in cytoplasmic Γ.

AB - Summary The volume-regulated anion channel (VRAC) is activated when a cell swells, and it plays a central role in maintaining cell volume in response to osmotic challenges. SWELL1 (LRRC8A) was recently identified as an essential component of VRAC. However, the identity of the pore-forming subunits of VRAC and how the channel is gated by cell swelling are unknown. Here, we show that SWELL1 and up to four other LRRC8 subunits assemble into heterogeneous complexes of ∼800 kDa. When reconstituted into bilayers, LRRC8 complexes are sufficient to form anion channels activated by osmolality gradients. In bilayers, as well as in cells, the single-channel conductance of the complexes depends on the LRRC8 composition. Finally, low ionic strength (Γ) in the absence of an osmotic gradient activates the complexes in bilayers. These data demonstrate that LRRC8 proteins together constitute the VRAC pore and that hypotonic stress can activate VRAC through a decrease in cytoplasmic Γ.

UR - http://www.scopus.com/inward/record.url?scp=84955600441&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84955600441&partnerID=8YFLogxK

U2 - 10.1016/j.cell.2015.12.031

DO - 10.1016/j.cell.2015.12.031

M3 - Article

C2 - 26824658

AN - SCOPUS:84955600441

VL - 164

SP - 499

EP - 511

JO - Cell

JF - Cell

SN - 0092-8674

IS - 3

ER -