Formation of hybrid cell-cell channels.
The oocyte cell-cell channel assay was used to demonstrate that connexin-43 is a cell-cell channel-forming protein as previously shown for connexin-32. Expression of connexin-32 in one and connexin-43 in the other oocyte of a pair results in the formation of junctional conductances at rates similar to those observed when only one or the other connexin is expressed in both oocytes of a pair. This suggests that hybrid cell-cell channels form in the oocyte system. Hybrid channels also form when a connexin-43 mRNA-injected oocyte is paired with a noninjected oocyte expressing endogenous connexin. The latter hybrids have properties apparently contributed by both types of hemichannels. Pure connexin-43 channels are not voltage gated, whereas pure oocyte channels are voltage dependent; hybrids of these channels rectify.
Werner
R
R
Department of Physiology and Biophysics, University of Miami School of Medicine, FL 33101.
Levine
E
E
Rabadan-Diehl
C
C
Dahl
G
G
D000818:Animals; D017630:Connexins; D004247:DNA / Q000235:genetics; D005260:Female; D007365:Intercellular Junctions / Q000502:physiology*; D007700:Kinetics; D008564:Membrane Potentials; D008565:Membrane Proteins / Q000235:genetics / Q000502:physiology*; D009865:Oocytes / Q000502:physiology; D012333:RNA, Messenger / Q000235:genetics; D014158:Transcription, Genetic; D014981:Xenopus
D017630:Connexins; D008565:Membrane Proteins; D012333:RNA, Messenger; D004247:DNA