Fig. 1. In vitro culture of myocytes derived from N-cadherin-null and E-cadherin-rescued N-cadherin-null embryos. Wild-type myocytes formed tightly adherent aggregates (A) after 3 days in culture. In comparison, small, less-compacted aggregates of N-cadherin-deficient myocytes were observed (B). Although the cells were less adhesive, small aggregates of mutant myocytes were observed beating synchronously, albeit more weakly compared with wild-type aggregates. Many mutant cells had difficulty remaining attached to the substrate, causing them to round up (C). Introduction of the MHC/Ecad transgene into the mutant background restored normal cell adhesion, resulting in large aggregates of strongly beating myocytes (D). Bar, 10 µm.