Gap junctional intercellular communication is established when connexin proteins oligomerize into connexon hemichannels, which then pair at the cell surface with connexons from neighboring cells to form functional gap junction channels. Gap junction channels routinely cluster into gap junction plaques, which can exhibit dynamic characteristics while under the frequent processes of formation and...

Connexin proteins form gap junctions, which permit direct exchange of cytoplasmic contents between neighboring cells. Evidence indicates that gap junctional intercellular communication (GJIC) is important for maintaining homeostasis and preventing cell transformation. Furthermore, connexins may have independent functions including tumor growth suppression. Most tumors express less connexins, ha...

Recently we found that electrophysiological (EP) heterogeneities between subepicardial and midmyocardial cells can form a substrate for reentrant ventricular arrhythmias. However, cell-to-cell coupling through gap junctions is expected to attenuate transmural heterogeneities between cell types spanning the ventricular wall. Because connexin43 (Cx43) is the principal ventricular gap junction pro...

A previous study from our laboratory has shown that a single targeted heavy ion irradiation (THIR; 15 Gy) to rabbit hearts increases connexin43 (Cx43) expression for 2 wk in association with an improvement of conduction, a decrease of the spatial inhomogeneity of repolarization, and a reduction of vulnerability to ventricular arrhythmias after myocardial infarction. This study investigated the ...

AIMS It is well known that connexin43 (Cx43) forms gap junctions. We recently showed that Cx43 is also part of a protein-interacting network that regulates excitability. Cardiac-specific truncation of Cx43 C-terminus (mutant 'Cx43D378stop') led to lethal arrhythmias. Cx43D378stop localized to the intercalated disc (ID); cell-cell coupling was normal, but there was significant sodium current (IN...

The present study was designed to explore the role of gap junctions in follicle-stimulating hormone (FSH) and transforming growth factor beta1 (TGF beta1)-stimulated steroidogenesis in ovarian granulosa cells of gonadotropin-primed immature rats. There were three specific aims. First, we investigated the effect of FSH and TGF beta1 as well as lindane (a general gap junction blocker) on the leve...

Chondrocytes in cartilage and bone cells population express connexin43 (Cx43) and gap junction intercellular communication (GJIC) is essential to synchronize cells for coordinated electrical, mechanical, metabolic and chemical communication in both tissues. Reduced Cx43 connectivity decreases chondrocyte differentiation and defective Cx43 causes skeletal defects. The carboxy terminal domain (CT...

Ovarian granulosa cells are coupled via gap junctions containing connexin43 (Cx43 or alpha-1 connexin). In the absence of Cx43, granulosa cells stop growing in an early preantral stage. However, the fact that granulosa cells of mature follicles express multiple connexins complicated interpretation of this finding. The present experiments were designed to clarify the role of Cx43 vs. these other...

Connexin43 (Cx43) has an important role in skeletal homeostasis, and Cx43 gene (Gja1) mutations have been linked to oculodentodigital dysplasia (ODDD), a human disorder characterized by prominent skeletal abnormalities. To determine the function of Cx43 at early steps of osteogenesis and its role in the ODDD skeletal phenotype, we have used the Dermo1 promoter to drive Gja1 ablation or induce a...

PURPOSE Intercellular communication through gap junctions was assessed in 8 to 10-week STZ diabetic rats to evaluate diabetes related effects on gap junctional conductance and permeability in short-term cultures of corporeal myocytes. MATERIALS AND METHODS Rats were made diabetic by a single intraperitoneal injection of STZ. Eight to 10 weeks later erectile function was evaluated in vivo and ...