Connexin mutant embryonic stem cells and human diseases

Abstract

Intercellular communication via gap junctions allows cells within multicellular organisms to share small mol-ecules. The effect of such interactions has been eluci-dated using mouse gene knockout strategies. Although several mutations in human gap junction-encoding con-nexin (Cx) have been described, Cx mutants in mice do not always recapitulate the human disease. Among the 20 mouse Cxs , Cx26 , Cx43 , and Cx45 play roles in early cardiac or placental development, and disruption of the genes results in lethality that hampers further analyses. Embryonic stem cells (ESCs) that lack Cx43 or Cx45 have made analysis feasible in both in vitro differ-entiated cell cultures and in vivo chimeric tissues. The success of mouse ESCs studies is leading to the use of induced pluripotent stem cells to learn more about the pathogenesis of human Cx diseases. This review sum-marizes the current status of mouse Cx disruption mod-els and ESC differentiation studies, and discusses their implication for understanding human Cx diseases.