Temporal expression of neurofilament polypeptides in differentiating neuroblastoma cells

NEURO-2A neuroblastoma cells were differentiated by the addition of dibutyryl-cyclic AMP, resulting in an increase in transcription of mRNA coding for the two neurofilament polypeptides NF-L and NF-M. The mRNAs for these two polypeptides appeared to be co-expressed with both being switched on at 24 h after the addition of drug. This was in contrast to NF-H whose induction was only seen at 60 h following addition of drug. These results are in good agreement with the expression time course previously reported in-vivo and suggest that the neurofilament triplet polypeptides can be divided into two subsets which appear to be under different genetic control mechanisms according to their time course of expression.