DIFFERENTIAL EXPRESSION OF NEUROD IN PRIMARY CULTURES OF CEREBRAL CORTICAL-NEURONS

We have investigated the expression patterns of a basic helix-loop-hel ix regulatory gene, neuroD, in primary cultures of murine cerebral cor tical neurons, The differentiation states of neurons in primary cultur es were determined by the sensitivity of neurons to glutamate toxicity and the expression of specific proteins such as the phosphorylated fo rm of a 200-kDa neurofilament, HPC-1/syntaxin 1A, and cell adhesion mo lecule L1. The expression of neuroD was determined by RT-PCR analysis and in situ hybridization. The experimental results thus obtained reve aled that neuronal maturation is initiated between Day 7 and Day 11 in the culture as already known, and that the expression of neuroD decre ases with increasing days in culture. Based on these findings, it was concluded that neuroD is expressed in immature neurons but not in matu re ones. (C) 1997 Academic Press.