Single-channel recordings of RyR1 at microsecond resolution in CMOS-suspended membranes.
Proc Natl Acad Sci U S A
; 115(8): E1789-E1798, 2018 02 20.
Article
em En
| MEDLINE
| ID: mdl-29432144
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.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Semicondutores
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Canal de Liberação de Cálcio do Receptor de Rianodina
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Bicamadas Lipídicas
Idioma:
En
Revista:
Proc Natl Acad Sci U S A
Ano de publicação:
2018
Tipo de documento:
Article