Differential Regulation of Connexin50 and Connexin46 by PI3K Signaling

Overview

Journal FEBS Lett

Specialty Biochemistry

Date 2015 May 4

PMID 25935417

Citations 16

Authors

Jennifer M Martinez

Hong-Zhan Wang

Richard Z Lin

Peter R Brink

Thomas W White

Affiliations

Soon will be listed here.

Abstract

Gap junction channels can modify their activity in response to cell signaling pathways. Here, we demonstrate that Connexin50 (Cx50) coupling, but not Connexin46 (Cx46), increased when co-expressed with a constitutively active p110α subunit of PI3K in Xenopus oocytes. In addition, inhibition of PI3K signaling by blocking p110α, or Akt, significantly decreased gap junctional conductance in Cx50 transfected HeLa cells, with no effect on Cx46. Alterations in coupling levels were not a result of reduced Cx50 unitary conductance, suggesting that changes in the number of active channels were responsible. These data indicate that Cx50 is specifically regulated by the PI3K signaling pathway.

Citing Articles

Combinatorial genetic manipulation of Cx50, PI3K and PTEN alters postnatal mouse lens growth and homeostasis.

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