The reversible inhibition of myoblast fusion by ethidium bromide (EB)

Ethidium bromide (EB) is a reversible inhibitor of myoblast fusion. The range over which EB is both inhibitory and reversible is narrow and is centered around 1 μg/ml. The EB sensitive period for myoblast fusion is very early during the induction of differentiation, at least 15 h prior to cell fusion. Fusion of myoblasts after release from EB inhibition does not require net DNA synthesis, nor is mitochondrial protein synthesis required for myoblast fusion. Rifampicin also causes similar reversible inhibition of fusion with some differences in the release kinetics.