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. 1995 May;68(5):1767–1775. doi: 10.1016/S0006-3495(95)80353-X

Single channel behavior of recombinant beta 2 gap junction connexons reconstituted into planar lipid bilayers.

L K Buehler 1, K A Stauffer 1, N B Gilula 1, N M Kumar 1
PMCID: PMC1282079  PMID: 7542035

Abstract

The beta 2 gap junction protein (Cx26) was expressed in an insect cell line by infection with a baculovirus vector containing the rat beta 2 cDNA. Isolated beta 2 gap junction connexons were reconstituted into planar lipid bilayers. Single channel activity was observed with a unitary conductance of 35-45 pS in 200 mM KCl. Channels with conductance values of 60 pS and 90-110 pS also coexisted with the lower conducting channel suggesting that there are channels with different conductance properties within a population of connexons. Channel activity was observed at voltages of up to 150 mV. Furthermore, the characterization of these channel properties from the beta 2 connexons that were generated by this heterologous expression system has provided the basis for identifying an endogenous beta 2 connexon channel in material reconstituted from native rat liver gap junctions.

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Selected References

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