Northern blot analysis of rat heart mRNA probed with a cDNA coding for the principal polypeptide of rat liver gap junctions demonstrated a 3.0-kb band. This band was observed only after hybridization and washing using low stringency conditions; high stringency conditions abolished the hybridization. A rat heart cDNA library was screened with the same cDNA probe under the permissive hybridizatio...

We examined the roles of the extracellular domains of a gap junction protein and a cell adhesion molecule in gap junction and adherens junction formation by altering cell interactions with antibody Fab fragments. Using immunoblotting and immunocytochemistry we demonstrated that Novikoff cells contained the gap junction protein, connexin43 (Cx43), and the cell adhesion molecule, A-CAM (N-cadheri...

The X-linked form of Charcot-Marie-Tooth disease (CMTX) is associated with mutations in the gene encoding connexin32 (Cx32), which is expressed in Schwann cells. We have compared the functional properties of 11 Cx32 mutations with those of the wild-type protein by testing their ability to form intercellular channels in the paired oocyte expression system. Although seven mutations were functiona...

Intercellular communication, especially gap junctional communication, is thought to be one of the highly differentiated functions of hepatocytes. In primary cultures of rat hepatocytes, it has been considered that the maintenance and the reinduction of differentiated functions is very difficult. In the present study, we succeeded in inducing the gap junctional protein connexin32 (Cx32) in adult...

Gap junctions are intercellular channels formed by the serial, head to head arrangement of two hemichannels. Each hemichannel is an oligomer of six protein subunits, which in vertebrates are encoded by the connexin gene family. All intercellular channels formed by connexins are sensitive to the relative difference in the membrane potential between coupled cells, the transjunctional voltage (Vj)...

The cellular localization, relation to other glial connexins (Cx30, Cx32, and Cx43), and developmental expression of Cx29 were investigated in the mouse central nervous system (CNS) with an anti-Cx29 antibody. Cx29 was enriched in subcellular fractions of myelin, and immunofluorescence for Cx29 was localized to oligodendrocytes and myelinated fibers throughout the brain and spinal cord. Oligode...

Hepatocellular carcinoma (HCC) is one of the common malignances in the world and is associated with high mortality and poor prognosis, partly due to early invasion and metastasis. Cx32 has been indicated to be involved in the progression of many cancers including HCC, but its relationship with tumor invasion and metastasis is still controversial. In the present study, the downregulated Cx32 in ...

Scaffolding of membrane proteins is a common strategy for forming complexes of proteins, including some connexins, within membrane microdomains. Here we describe studies indicating that Cx32 interacts with a PDZ-containing scaffolding protein, Dlgh1 (Discs Large homolog 1). Initial screens of liver lysates using antibody arrays indicated an interaction between Cx32 and Dlgh1 that was confirmed ...

Oligodendrocytes in vivo form heterologous gap junctions with astrocytes. These oligodendrocyte/astrocyte (A/O) gap junctions contain multiple connexins (Cx), including Cx26, Cx30, and Cx43 on the astrocyte side, and Cx32, Cx29, and Cx47 on the oligodendrocyte side. We investigated connexin associations at A/O gap junctions on oligodendrocytes in normal and Cx32 knockout (KO) mice. Immunoblotti...