DIFFERENTIAL EXPRESSION OF NEURON-SPECIFIC ENOLASE MESSENGER-RNA IN MOUSE NEUROBLASTOMA-CELLS IN RESPONSE TO DIFFERENTIATION-INDUCING AGENTS

1. The mouse neuroblasma cell line N-115 was used as a model system to study neuronal differentiation induced by treatment of cells with dif ferent agents. 2. The extent of morphological differentiation obtained with dibutyryl cyclic AMP (dbc-AMP), dimethyl sulfoxide (DMSO), retin oic acid (RA), and serum-free medium was correlated to the expression of the mRNA for the gamma isoform of the glycolytic enzyme enolase, a recognized neuron-specific marker. 3. A 4-day treatment of the cells w ith any of the differentiation inducing agents used in this study resu lted in the extension of long neurites, though differences in cell bod y shape were observed depending on the agent used. 4. Northern blot an alysis revealed that changes in the level of gamma enolase-specific mR NA correlate with the extent of morphological differentiation, with a 5- to 20-fold increase depending on the differentiation inducing agent used. 5. Finally, we found that a high cell density causes a signific ative increase in the level of the gamma enolase-specific message in c ells maintained in growing conditions.