Demonstration of Cx45 knockout mouse embryos (E9.5) with LacZ expression driven by the Cx45 promoter in place of endogenous Cx45 expression. A) Wild-type B-E) Heterozygous Cx45 knockout, F) Homozygous Cx45 knockout.

Views of the dissected Heart tube from Cx45 knockout mouse embryos (E9.5) with LacZ expression driven by the Cx45 promoter in place of endogenous Cx45 expression.

Demonstration of gap junction cell-cell coupling in cultured 3T3 cells. A micropipette injects fluorescent dye into the middle cell, which then slowly spreads through gap junctions into neighboring cells. (Image Provided by Richard Francis)

Ncad(Leftwt,_Rightko)

Cardiac neural crest cells emerge from explants of the hindbrain neural fold derived from E8.5 mouse embryos. Timelapse images recorded every 10 min for 20 hrs. (Image by Xin Xu)

Cell migration in cultured embryo sections demonstrating primordial germ cell migration in mouse embryos (embryonic day 9.5). Primordial germ cells appear fluorescent because they contain the transgene Oct4-EGFP.