In an animal model of MI, the up-regulation of c-Src tyrosine kinase and an increase in the level of phosphorylated Tyr 416 c-Src (the active form of c-Src) resulted in the down-regulation of connexin43 (Cx43) via competition between phosphorylated c-Src and Cx43 for a binding site at zonula occludens-1, an intercalated disk scaffolding protein (Kieken et al., 2009). The gene discussed is SRC; the disease is myocardial infarction.