P21(RAS) SUPPORTS THE SURVIVAL OF CHICK EMBRYONIC MOTOR-NEURONS

VARIOUS trophic factors present in muscle extract can promote the surv ival of cultured Inotor neurones. However, little is known about the s ignal transduction pathways used in these cells. The proto-oncogene pr oduct p21(ras) has been shown to play an important role in proliferati ve and differentiative signalling pathways. We report here that cytopl asmic introduction of its oncogenic form, p21(ras)(G12V), fully suppor ts the in vitro survival of chick embryonic motor neurones. The proto- oncogenic form of p21(ras) also showed a dose-dependent survival effec t, while a C-terminally truncated counterpart of p21(ras)(G12V) was in effective. These results suggest an involvement of p21(ras) in signal transduction pathways leading to motor neurone survival and may be of relevance for the development of therapeutic strategies for motor neur one disease.