The connexin32 (cx32) gene codes for the gap junction protein found in liver, pancreas and nervous tissue. Recently mutations in the coding region of this gene have been associated with the dominant X-linked form of Charcot-Marie-Tooth (CMTX1) neuropathy. Since some CMTX1 patients sho,* no mutations in their cx32 gene coding region, it was speculated that these patients carry mutations in the p...

X-linked Charcot-Marie-Tooth disease (CMTX) is a clinically heterogeneous hereditary motor and sensory neuropathy with X-linked transmission. Common clinical manifestations of CMTX, as in other forms of Charcot-Marie-Tooth disease (CMT), are distal muscle wasting and weakness, hyporeflexia, distal sensory disturbance, and foot deformities. Motor nerve conduction velocity is reduced. In male pat...

Direct intercellular signal transduction is achieved by the passage of small molecules through gap junctions (GJ). Previous studies in our laboratory showed that the liver tumor promoter phenobarbital (PB) reversibly decreases the abundance of the GJ protein connexin32 (Cx32) in both preneoplastic-altered hepatic foci and centrolobular hepatocytes (M. J. Neveu et al., Cancer Commun., 2: 21-31, ...

Connexins are subunits of gap junction channels, which mediate the direct transfer of ions, second messenger molecules and other metabolites between contacting cells. Gap junctions are thought to be involved in tissue homeostasis, embryonic development and the control of cell proliferation [1,2]. It has also been suggested that the loss of intercellular communication via gap junctions may contr...

AIMS acute myocardial ischaemia induces a decrease in resting membrane potential [which leads to reduction of action potential (AP) V(max)] and intracellular acidification (which closes gap junctions). Both contribute to conduction slowing. We hypothesized that ventricular expression of the skeletal muscle Na(+) channel, Nav1.4 (which activates fully at low membrane potentials), or connexin32 (...

Panglial networks are essential for normal physiology in the CNS, and the function of distinct connexins participating in these networks is not well understood. We generated Connexin32 (Cx32)-deficient mice with additional deletion of astrocytic Cx43 to explore the role of both connexins in panglial networks. Cx43/Cx32 double knock-out (dKO) mice revealed strong microglial activation in corpus ...

Considerable evidence indicates a critical role for dopamine in the reinforcing effects of cocaine. Because dopamine has been shown to be a critical modulator of gap junction communication in both eye and brain, we sought to examine whether extended intravenous cocaine self-administration would affect the expression of gap junction channel-forming proteins (connexins). Using ELISA, Western anal...

Connexin32 (Cx32) mutants were studied by double voltage clamp in Xenopus oocytes to determine the role of basic COOH-terminal residues in gap junction channel gating by CO2 and transjunctional voltage. Replacement of five arginines with N (5R/N) or T residues in the initial COOH-terminal domain (CT1) of Cx32 enhanced CO2 sensitivity. The positive charge, rather than the R residue per se, is re...