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Altered formation of hemichannels and gap junction channels caused by C-terminal connexin-32 mutations.
Castro C
,
Gómez-Hernandez JM
,
Silander K
,
Barrio LC
.
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Hexamers of connexins (Cxs) form hemichannels that dock tightly in series via their extracellular domains to give rise to gap junction channels. Here we examined the ability of a variety of C-terminal Cx32 mutations, most of which have been identified in X-linked Charcot-Marie-Tooth disease, to form hemichannels and to complete gap junction channels using the Xenopus oocyte system. First, we show that undocked wild-type Cx32 hemichannels at the plasma membrane can be detected as opening channels activated by depolarization. We have been able to estimate the efficiency of assembly of complete channels by measuring the time-dependent incorporation of preformed hemichannels into gap junction channels after cell-to-cell contact. These data offer strong evidence that hemichannels are the direct precursors of gap junction channels. Of 11 Cx32 mutants tested, a group of 5 mutations prevented the formation of functional hemichannels at the cell surface, whereas 4 mutations were fully able to form precursors but reduced the ability of hemichannels to assemble into complete channels, and 2 mutants formed channels normally. The data revealed that a minimum length of human Cx32 including the residue Arg-215 is required for the expression of hemichannels at the cell surface and that the efficiency of hemichannel incorporation into complete channels decreased gradually with the progressive shortening of the cytoplasmic C-terminal domain.
Balice-Gordon,
Functional gap junctions in the schwann cell myelin sheath.
1998, Pubmed
Balice-Gordon,
Functional gap junctions in the schwann cell myelin sheath.
1998,
Pubmed
Barrio,
Species-specific voltage-gating properties of connexin-45 junctions expressed in Xenopus oocytes.
1997,
Pubmed
,
Xenbase
Barrio,
Gap junctions formed by connexins 26 and 32 alone and in combination are differently affected by applied voltage.
1991,
Pubmed
,
Xenbase
Bergoffen,
Connexin mutations in X-linked Charcot-Marie-Tooth disease.
1993,
Pubmed
Bone,
Connexin32 and X-linked Charcot-Marie-Tooth disease.
1997,
Pubmed
Bone,
New connexin32 mutations associated with X-linked Charcot-Marie-Tooth disease.
1995,
Pubmed
Bort,
Mutational analysis of the MPZ, PMP22 and Cx32 genes in patients of Spanish ancestry with Charcot-Marie-Tooth disease and hereditary neuropathy with liability to pressure palsies.
1997,
Pubmed
Bruzzone,
Connections with connexins: the molecular basis of direct intercellular signaling.
1996,
Pubmed
Bruzzone,
Null mutations of connexin32 in patients with X-linked Charcot-Marie-Tooth disease.
1994,
Pubmed
,
Xenbase
Chow,
Opening of single gap junction channels during formation of electrical coupling between embryonic muscle cells.
1987,
Pubmed
,
Xenbase
Dahl,
Cell/cell channel formation involves disulfide exchange.
1991,
Pubmed
Dahl,
Attempts to define functional domains of gap junction proteins with synthetic peptides.
1994,
Pubmed
,
Xenbase
DeVries,
Hemi-gap-junction channels in solitary horizontal cells of the catfish retina.
1992,
Pubmed
Deschênes,
Altered trafficking of mutant connexin32.
1997,
Pubmed
Dunham,
Immunolocalization and expression of functional and nonfunctional cell-to-cell channels from wild-type and mutant rat heart connexin43 cDNA.
1992,
Pubmed
,
Xenbase
Ebihara,
Xenopus connexin38 forms hemi-gap-junctional channels in the nonjunctional plasma membrane of Xenopus oocytes.
1996,
Pubmed
,
Xenbase
Ebihara,
Distinct behavior of connexin56 and connexin46 gap junctional channels can be predicted from the behavior of their hemi-gap-junctional channels.
1995,
Pubmed
,
Xenbase
Fairweather,
Mutations in the connexin 32 gene in X-linked dominant Charcot-Marie-Tooth disease (CMTX1).
1994,
Pubmed
Falk,
Cell-free synthesis and assembly of connexins into functional gap junction membrane channels.
1997,
Pubmed
Foote,
The pattern of disulfide linkages in the extracellular loop regions of connexin 32 suggests a model for the docking interface of gap junctions.
1998,
Pubmed
,
Xenbase
Ghoshroy,
Preparation, characterization, and structure of half gap junctional layers split with urea and EGTA.
1995,
Pubmed
Gilula,
Metabolic coupling, ionic coupling and cell contacts.
1972,
Pubmed
Goodenough,
The splitting of hepatocyte gap junctions and zonulae occludentes with hypertonic disaccharides.
1974,
Pubmed
Goodenough,
Topological distribution of two connexin32 antigenic sites in intact and split rodent hepatocyte gap junctions.
1988,
Pubmed
Green,
Ion-channel assembly.
1995,
Pubmed
Gupta,
Bovine connexin44, a lens gap junction protein: molecular cloning, immunologic characterization, and functional expression.
1994,
Pubmed
,
Xenbase
Hahn,
X-linked dominant hereditary motor and sensory neuropathy.
1990,
Pubmed
Haubrich,
Incompatibility of connexin 40 and 43 Hemichannels in gap junctions between mammalian cells is determined by intracellular domains.
1996,
Pubmed
Hoh,
Structure of the extracellular surface of the gap junction by atomic force microscopy.
1993,
Pubmed
Hoh,
Atomic force microscopy and dissection of gap junctions.
1991,
Pubmed
Ionasescu,
Point mutations of the connexin32 (GJB1) gene in X-linked dominant Charcot-Marie-Tooth neuropathy.
1994,
Pubmed
Ionasescu,
Correlation between connexin 32 gene mutations and clinical phenotype in X-linked dominant Charcot-Marie-Tooth neuropathy.
1996,
Pubmed
Kumar,
Synthesis and assembly of human beta 1 gap junctions in BHK cells by DNA transfection with the human beta 1 cDNA.
1995,
Pubmed
Kumar,
Cloning and characterization of human and rat liver cDNAs coding for a gap junction protein.
1986,
Pubmed
Laing,
Degradation of connexin43 gap junctions involves both the proteasome and the lysosome.
1997,
Pubmed
Li,
Properties and regulation of gap junctional hemichannels in the plasma membranes of cultured cells.
1996,
Pubmed
Loewenstein,
Quantum jumps of conductance during formation of membrane channels at cell-cell junction.
1978,
Pubmed
,
Xenbase
Manjunath,
Detergent sensitivity and splitting of isolated liver gap junctions.
1984,
Pubmed
Meyer,
Inhibition of gap junction and adherens junction assembly by connexin and A-CAM antibodies.
1992,
Pubmed
Musil,
Multisubunit assembly of an integral plasma membrane channel protein, gap junction connexin43, occurs after exit from the ER.
1993,
Pubmed
,
Xenbase
Nelis,
Mutation analysis of the connexin 32 (Cx32) gene in Charcot-Marie-Tooth neuropathy type 1: identification of five new mutations.
1997,
Pubmed
Oh,
Changes in permeability caused by connexin 32 mutations underlie X-linked Charcot-Marie-Tooth disease.
1997,
Pubmed
,
Xenbase
Omori,
Connexin 32 mutations from X-linked Charcot-Marie-Tooth disease patients: functional defects and dominant negative effects.
1996,
Pubmed
Paul,
Connexin46, a novel lens gap junction protein, induces voltage-gated currents in nonjunctional plasma membrane of Xenopus oocytes.
1991,
Pubmed
,
Xenbase
Perkins,
Three-dimensional structure of the gap junction connexon.
1997,
Pubmed
Rabadan-Diehl,
A connexin-32 mutation associated with Charcot-Marie-Tooth disease does not affect channel formation in oocytes.
1994,
Pubmed
Ressot,
X-linked dominant Charcot-Marie-Tooth neuropathy (CMTX): new mutations in the connexin32 gene.
1996,
Pubmed
Ressot,
Connexin32 mutations associated with X-linked Charcot-Marie-Tooth disease show two distinct behaviors: loss of function and altered gating properties.
1998,
Pubmed
,
Xenbase
Revel,
Hexagonal array of subunits in intercellular junctions of the mouse heart and liver.
1967,
Pubmed
Silander,
Screening for connexin 32 mutations in Charcot-Marie-Tooth disease families with possible X-linked inheritance.
1997,
Pubmed
Tan,
Novel mutations in the connexin 32 gene associated with X-linked Charcot-Marie tooth disease.
1996,
Pubmed
Tibbitts,
Diffraction diagnosis of protein folding in gap junction connexons.
1990,
Pubmed
Trexler,
Voltage gating and permeation in a gap junction hemichannel.
1996,
Pubmed
,
Xenbase
Valiunas,
Conductances and selective permeability of connexin43 gap junction channels examined in neonatal rat heart cells.
1997,
Pubmed
White,
Selective interactions among the multiple connexin proteins expressed in the vertebrate lens: the second extracellular domain is a determinant of compatibility between connexins.
1994,
Pubmed
,
Xenbase
