Connexin-43 is known to interact directly with ZO-1 in cardiac myocytes, but little is known
about the role of ZO-1 in connexin-43 function. In cardiac myocytes, constitutively active c-
Src inhibited endogenous interaction between connexin-43 and ZO-1 by binding to
connexin-43. In HEK293 cells, by contrast, a connexin-43 mutant lacking the Src
phosphorylation site (Tyr 265) interacted with ZO-1 despite cotransfection of a constitutively
active c-Src. Moreover, in vitro binding assays using recombinant proteins synthesized from …