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Temperature-sensitive gating of hCx26: high-resolution Raman spectroscopy sheds light on conformational changes.

ABSTRACT: The temperature-sensitive gating of human Connexin 26 (hCx26) was analyzed with confocal Raman microscopy. High-resolution Raman spectra covering the spectral range between 400 and 1500 rel. cm(-1) with a spectral resolution of 1 cm(-1) were fully annotated, revealing notable differences between the spectrum recorded from solubilized hCx26 in Ca(2+)-buffered POPC at 10°C and any other set of protein conditions (temperature, Ca(2+) presence, POPC presence). Spectral components originating from specific amino acids show that the TM1/EL1 parahelix and probably the TM4 trans-membrane helix and the plug domain are involved in the gating process responsible for fully closing the hemichannel.

SUBMITTER: Kniggendorf AK

PROVIDER: S-EPMC4102348 | biostudies-literature | 2014 Jul

REPOSITORIES: biostudies-literature

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Temperature-sensitive gating of hCx26: high-resolution Raman spectroscopy sheds light on conformational changes.

Kniggendorf Ann-Kathrin AK Meinhardt-Wollweber Merve M Yuan Xiaogang X Roth Bernhard B Seifert Astrid A Fertig Niels N Zeilinger Carsten C

Biomedical optics express 20140606 7

The temperature-sensitive gating of human Connexin 26 (hCx26) was analyzed with confocal Raman microscopy. High-resolution Raman spectra covering the spectral range between 400 and 1500 rel. cm(-1) with a spectral resolution of 1 cm(-1) were fully annotated, revealing notable differences between the spectrum recorded from solubilized hCx26 in Ca(2+)-buffered POPC at 10°C and any other set of protein conditions (temperature, Ca(2+) presence, POPC presence). Spectral components originating from sp ...[more]

PMID: 25071948

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