Dataset Information

Single-channel recordings of RyR1 at microsecond resolution in CMOS-suspended membranes.

ABSTRACT: Single-channel recordings are widely used to explore functional properties of ion channels. Typically, such recordings are performed at bandwidths of less than 10 kHz because of signal-to-noise considerations, limiting the temporal resolution available for studying fast gating dynamics to greater than 100 µs. Here we present experimental methods that directly integrate suspended lipid bilayers with high-bandwidth, low-noise transimpedance amplifiers based on complementary metal-oxide-semiconductor (CMOS) integrated circuits (IC) technology to achieve bandwidths in excess of 500 kHz and microsecond temporal resolution. We use this CMOS-integrated bilayer system to study the type 1 ryanodine receptor (RyR1), a Ca2+-activated intracellular Ca2+-release channel located on the sarcoplasmic reticulum. We are able to distinguish multiple closed states not evident with lower bandwidth recordings, suggesting the presence of an additional Ca2+ binding site, distinct from the site responsible for activation. An extended beta distribution analysis of our high-bandwidth data can be used to infer closed state flicker events as fast as 35 ns. These events are in the range of single-file ion translocations.

SUBMITTER: Hartel AJW

PROVIDER: S-EPMC5828579 | biostudies-literature | 2018 Feb

REPOSITORIES: biostudies-literature

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Single-channel recordings of RyR1 at microsecond resolution in CMOS-suspended membranes.

Hartel Andreas J W AJW Ong Peijie P Schroeder Indra I Giese M Hunter MH Shekar Siddharth S Clarke Oliver B OB Zalk Ran R Marks Andrew R AR Hendrickson Wayne A WA Shepard Kenneth L KL

Proceedings of the National Academy of Sciences of the United States of America 20180205 8

Single-channel recordings are widely used to explore functional properties of ion channels. Typically, such recordings are performed at bandwidths of less than 10 kHz because of signal-to-noise considerations, limiting the temporal resolution available for studying fast gating dynamics to greater than 100 µs. Here we present experimental methods that directly integrate suspended lipid bilayers with high-bandwidth, low-noise transimpedance amplifiers based on complementary metal-oxide-semiconduct ...[more]

PMID: 29432144

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Dataset Information

Single-channel recordings of RyR1 at microsecond resolution in CMOS-suspended membranes.

Publications

Single-channel recordings of RyR1 at microsecond resolution in CMOS-suspended membranes.

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