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Properties of a nonjunctional current expressed from a rat connexin46 cDNA in Xenopus oocytes

Connexin46 (cxn46) is a gap junctional protein that was cloned from a rat lens cDNA library. Expression of cxn46 in solitary Xenopus oocytes resulted in the development of a large time- and voltage-dependent current that was not observed in noninjected control oocytes or in oocytes injected with mRN...

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Formato: Texto
Lenguaje:English
Publicado: The Rockefeller University Press 1993
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Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2229167/
https://www.ncbi.nlm.nih.gov/pubmed/7690837
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description Connexin46 (cxn46) is a gap junctional protein that was cloned from a rat lens cDNA library. Expression of cxn46 in solitary Xenopus oocytes resulted in the development of a large time- and voltage-dependent current that was not observed in noninjected control oocytes or in oocytes injected with mRNA for cxn43 or cxn32. The cxn46-induced current activated at potentials positive to -20 mV. On repolarization to -40 mV, the current deactivated over a period of several seconds. Removal of external calcium caused a marked increase in the amplitude of the cxn46-induced current, shifted the steady-state activation curve to more negative potentials, and altered the kinetics of activation and deactivation. Increasing external calcium had the opposite effect. The ability of cxn46 to induce the formation of cell-to-cell channels was tested in the oocyte pair system. Oocyte pairs injected with cxn46 mRNA + antisense oligonucleotides for Xenopus cxn38 were strongly coupled. In contrast, oocyte pairs injected with antisense alone showed no coupling. The inactivation kinetics of the gap junctional channels resembled the deactivation kinetics of the cxn46-induced current in solitary oocytes.
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spelling pubmed-22291672008-04-23 Properties of a nonjunctional current expressed from a rat connexin46 cDNA in Xenopus oocytes J Gen Physiol Articles Connexin46 (cxn46) is a gap junctional protein that was cloned from a rat lens cDNA library. Expression of cxn46 in solitary Xenopus oocytes resulted in the development of a large time- and voltage-dependent current that was not observed in noninjected control oocytes or in oocytes injected with mRNA for cxn43 or cxn32. The cxn46-induced current activated at potentials positive to -20 mV. On repolarization to -40 mV, the current deactivated over a period of several seconds. Removal of external calcium caused a marked increase in the amplitude of the cxn46-induced current, shifted the steady-state activation curve to more negative potentials, and altered the kinetics of activation and deactivation. Increasing external calcium had the opposite effect. The ability of cxn46 to induce the formation of cell-to-cell channels was tested in the oocyte pair system. Oocyte pairs injected with cxn46 mRNA + antisense oligonucleotides for Xenopus cxn38 were strongly coupled. In contrast, oocyte pairs injected with antisense alone showed no coupling. The inactivation kinetics of the gap junctional channels resembled the deactivation kinetics of the cxn46-induced current in solitary oocytes. The Rockefeller University Press 1993-07-01 /pmc/articles/PMC2229167/ /pubmed/7690837 Text en This article is distributed under the terms of an Attribution–Noncommercial–Share Alike–No Mirror Sites license for the first six months after the publication date (see http://www.rupress.org/terms). After six months it is available under a Creative Commons License (Attribution–Noncommercial–Share Alike 4.0 Unported license, as described at http://creativecommons.org/licenses/by-nc-sa/4.0/).
spellingShingle Articles
Properties of a nonjunctional current expressed from a rat connexin46 cDNA in Xenopus oocytes
title Properties of a nonjunctional current expressed from a rat connexin46 cDNA in Xenopus oocytes
title_full Properties of a nonjunctional current expressed from a rat connexin46 cDNA in Xenopus oocytes
title_fullStr Properties of a nonjunctional current expressed from a rat connexin46 cDNA in Xenopus oocytes
title_full_unstemmed Properties of a nonjunctional current expressed from a rat connexin46 cDNA in Xenopus oocytes
title_short Properties of a nonjunctional current expressed from a rat connexin46 cDNA in Xenopus oocytes
title_sort properties of a nonjunctional current expressed from a rat connexin46 cdna in xenopus oocytes
topic Articles
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2229167/
https://www.ncbi.nlm.nih.gov/pubmed/7690837