Coordinated Movement of Cytoplasmic and Transmembrane Domains of RyR1 upon Gating

Montserrat Samsó, Wei Feng, Isaac N Pessah, P. D. Allen

Research output: Contribution to journalArticle

91 Citations (Scopus)

Abstract

Ryanodine receptor type 1 (RyR1) produces spatially and temporally defined Ca 2+ signals in several cell types. How signals received in the cytoplasmic domain are transmitted to the ion gate and how the channel gates are unknown. We used EGTA or neuroactive PCB 95 to stabilize the full closed or open states of RyR1. Single-channel measurements in the presence of FKBP12 indicate that PCB 95 inverts the thermodynamic stability of RyR1 and locks it in a long-lived open state whose unitary current is indistinguishable from the native open state. We analyzed two datasets of 15,625 and 18,527 frozen-hydrated RyR1-FKBP12 particles in the closed and open conformations, respectively, by cryo-electron microscopy. Their corresponding three-dimensional structures at 10.2 Å resolution refine the structure surrounding the ion pathway previously identified in the closed conformation: two right-handed bundles emerging from the putative ion gate (the cytoplasmic "inner branches" and the transmembrane "inner helices"). Furthermore, six of the identifiable transmembrane segments of RyR1 have similar organization to those of the mammalian Kv1.2 potassium channel. Upon gating, the distal cytoplasmic domains move towards the transmembrane domain while the central cytoplasmic domains move away from it, and also away from the 4-fold axis. Along the ion pathway, precise relocation of the inner helices and inner branches results in an approximately 4 Å diameter increase of the ion gate. Whereas the inner helices of the K + channels and of the RyR1 channel cross-correlate best with their corresponding open/closed states, the cytoplasmic inner branches, which are not observed in the K + channels, appear to have at least as important a role as the inner helices for RyR1 gating. We propose a theoretical model whereby the inner helices, the inner branches, and the h1 densities together create an efficient novel gating mechanism for channel opening by relaxing two right-handed bundle structures along a common 4-fold axis.

Original languageEnglish (US)
Article numbere1000085
JournalPLoS Biology
Volume7
Issue number4
DOIs
StatePublished - Apr 2009

Fingerprint

ryanodine receptors
Ryanodine Receptor Calcium Release Channel
ions
potassium channels
Tacrolimus Binding Protein 1A
Ions
Conformations
Kv1.2 Potassium Channel
Cryoelectron Microscopy
Relocation
Egtazic Acid
Ion Channels
Thermodynamics
thermodynamics
Electron microscopy
Thermodynamic stability
Theoretical Models

ASJC Scopus subject areas

  • Agricultural and Biological Sciences(all)
  • Biochemistry, Genetics and Molecular Biology(all)
  • Immunology and Microbiology(all)
  • Neuroscience(all)

Cite this

Coordinated Movement of Cytoplasmic and Transmembrane Domains of RyR1 upon Gating. / Samsó, Montserrat; Feng, Wei; Pessah, Isaac N; Allen, P. D.

In: PLoS Biology, Vol. 7, No. 4, e1000085, 04.2009.

Research output: Contribution to journalArticle

Samsó, Montserrat ; Feng, Wei ; Pessah, Isaac N ; Allen, P. D. / Coordinated Movement of Cytoplasmic and Transmembrane Domains of RyR1 upon Gating. In: PLoS Biology. 2009 ; Vol. 7, No. 4.
@article{eb37898c08c946e68118969d40129101,
title = "Coordinated Movement of Cytoplasmic and Transmembrane Domains of RyR1 upon Gating",
abstract = "Ryanodine receptor type 1 (RyR1) produces spatially and temporally defined Ca 2+ signals in several cell types. How signals received in the cytoplasmic domain are transmitted to the ion gate and how the channel gates are unknown. We used EGTA or neuroactive PCB 95 to stabilize the full closed or open states of RyR1. Single-channel measurements in the presence of FKBP12 indicate that PCB 95 inverts the thermodynamic stability of RyR1 and locks it in a long-lived open state whose unitary current is indistinguishable from the native open state. We analyzed two datasets of 15,625 and 18,527 frozen-hydrated RyR1-FKBP12 particles in the closed and open conformations, respectively, by cryo-electron microscopy. Their corresponding three-dimensional structures at 10.2 {\AA} resolution refine the structure surrounding the ion pathway previously identified in the closed conformation: two right-handed bundles emerging from the putative ion gate (the cytoplasmic {"}inner branches{"} and the transmembrane {"}inner helices{"}). Furthermore, six of the identifiable transmembrane segments of RyR1 have similar organization to those of the mammalian Kv1.2 potassium channel. Upon gating, the distal cytoplasmic domains move towards the transmembrane domain while the central cytoplasmic domains move away from it, and also away from the 4-fold axis. Along the ion pathway, precise relocation of the inner helices and inner branches results in an approximately 4 {\AA} diameter increase of the ion gate. Whereas the inner helices of the K + channels and of the RyR1 channel cross-correlate best with their corresponding open/closed states, the cytoplasmic inner branches, which are not observed in the K + channels, appear to have at least as important a role as the inner helices for RyR1 gating. We propose a theoretical model whereby the inner helices, the inner branches, and the h1 densities together create an efficient novel gating mechanism for channel opening by relaxing two right-handed bundle structures along a common 4-fold axis.",
author = "Montserrat Sams{\'o} and Wei Feng and Pessah, {Isaac N} and Allen, {P. D.}",
year = "2009",
month = "4",
doi = "10.1371/journal.pbio.1000085",
language = "English (US)",
volume = "7",
journal = "PLoS Biology",
issn = "1544-9173",
publisher = "Public Library of Science",
number = "4",

}

TY - JOUR

T1 - Coordinated Movement of Cytoplasmic and Transmembrane Domains of RyR1 upon Gating

AU - Samsó, Montserrat

AU - Feng, Wei

AU - Pessah, Isaac N

AU - Allen, P. D.

PY - 2009/4

Y1 - 2009/4

N2 - Ryanodine receptor type 1 (RyR1) produces spatially and temporally defined Ca 2+ signals in several cell types. How signals received in the cytoplasmic domain are transmitted to the ion gate and how the channel gates are unknown. We used EGTA or neuroactive PCB 95 to stabilize the full closed or open states of RyR1. Single-channel measurements in the presence of FKBP12 indicate that PCB 95 inverts the thermodynamic stability of RyR1 and locks it in a long-lived open state whose unitary current is indistinguishable from the native open state. We analyzed two datasets of 15,625 and 18,527 frozen-hydrated RyR1-FKBP12 particles in the closed and open conformations, respectively, by cryo-electron microscopy. Their corresponding three-dimensional structures at 10.2 Å resolution refine the structure surrounding the ion pathway previously identified in the closed conformation: two right-handed bundles emerging from the putative ion gate (the cytoplasmic "inner branches" and the transmembrane "inner helices"). Furthermore, six of the identifiable transmembrane segments of RyR1 have similar organization to those of the mammalian Kv1.2 potassium channel. Upon gating, the distal cytoplasmic domains move towards the transmembrane domain while the central cytoplasmic domains move away from it, and also away from the 4-fold axis. Along the ion pathway, precise relocation of the inner helices and inner branches results in an approximately 4 Å diameter increase of the ion gate. Whereas the inner helices of the K + channels and of the RyR1 channel cross-correlate best with their corresponding open/closed states, the cytoplasmic inner branches, which are not observed in the K + channels, appear to have at least as important a role as the inner helices for RyR1 gating. We propose a theoretical model whereby the inner helices, the inner branches, and the h1 densities together create an efficient novel gating mechanism for channel opening by relaxing two right-handed bundle structures along a common 4-fold axis.

AB - Ryanodine receptor type 1 (RyR1) produces spatially and temporally defined Ca 2+ signals in several cell types. How signals received in the cytoplasmic domain are transmitted to the ion gate and how the channel gates are unknown. We used EGTA or neuroactive PCB 95 to stabilize the full closed or open states of RyR1. Single-channel measurements in the presence of FKBP12 indicate that PCB 95 inverts the thermodynamic stability of RyR1 and locks it in a long-lived open state whose unitary current is indistinguishable from the native open state. We analyzed two datasets of 15,625 and 18,527 frozen-hydrated RyR1-FKBP12 particles in the closed and open conformations, respectively, by cryo-electron microscopy. Their corresponding three-dimensional structures at 10.2 Å resolution refine the structure surrounding the ion pathway previously identified in the closed conformation: two right-handed bundles emerging from the putative ion gate (the cytoplasmic "inner branches" and the transmembrane "inner helices"). Furthermore, six of the identifiable transmembrane segments of RyR1 have similar organization to those of the mammalian Kv1.2 potassium channel. Upon gating, the distal cytoplasmic domains move towards the transmembrane domain while the central cytoplasmic domains move away from it, and also away from the 4-fold axis. Along the ion pathway, precise relocation of the inner helices and inner branches results in an approximately 4 Å diameter increase of the ion gate. Whereas the inner helices of the K + channels and of the RyR1 channel cross-correlate best with their corresponding open/closed states, the cytoplasmic inner branches, which are not observed in the K + channels, appear to have at least as important a role as the inner helices for RyR1 gating. We propose a theoretical model whereby the inner helices, the inner branches, and the h1 densities together create an efficient novel gating mechanism for channel opening by relaxing two right-handed bundle structures along a common 4-fold axis.

UR - http://www.scopus.com/inward/record.url?scp=67649637588&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=67649637588&partnerID=8YFLogxK

U2 - 10.1371/journal.pbio.1000085

DO - 10.1371/journal.pbio.1000085

M3 - Article

C2 - 19402748

AN - SCOPUS:67649637588

VL - 7

JO - PLoS Biology

JF - PLoS Biology

SN - 1544-9173

IS - 4

M1 - e1000085

ER -