The proportion altering factor (PAF) and the in vitro transdifferentiation of isolated striated muscle of jellyfish into nerve cells.

The effect of proportion altering factor (PAF) on the transdifferentiation of isolated striated muscle into RFamide-positive nerve cells was investigated. The factor reduces incorporation of 3H-thymidine into replicating DNA; the effect is concentration-dependent and reversible. Transdifferentiation to nerve cells increases by up to 60% if PAF is applied shortly before or at the time of initiation of DNA synthesis. When treatment was terminated 4 h before the start of S-phase or when PAF was applied at the peak of S-phase no increase in nerve cell formation was observed.