Dopamine-stimulated dephosphorylation of connexin 36 mediates AII amacrine cell uncoupling.

ABSTRACT: Gap junction proteins form the substrate for electrical coupling between neurons. These electrical synapses are widespread in the CNS and serve a variety of important functions. In the retina, connexin 36 (Cx36) gap junctions couple AII amacrine cells and are a requisite component of the high-sensitivity rod photoreceptor pathway. AII amacrine cell coupling strength is dynamically regulated by background light intensity, and uncoupling is thought to be mediated by dopamine signaling via D(1)-like receptors. One proposed mechanism for this uncoupling involves dopamine-stimulated phosphorylation of Cx36 at regulatory sites, mediated by protein kinase A. Here we provide evidence against this hypothesis and demonstrate a direct relationship between Cx36 phosphorylation and AII amacrine cell co

SUBMITTER: Kothmann WW 

PROVIDER: S-EPMC2839935 | biostudies-literature | 2009 Nov

REPOSITORIES: biostudies-literature