| Abstract: | Some of the events which characterize neuronal terminal differentiation have been studied in rat cortical neurons cultured in a selective synthetic medium for a period which corresponds to terminal brain maturation in vivo. In particular, we have studied the effect of T3 on the synthesis of nuclear proteins and the expression of the mRNAs which encode different variants of T3 nuclear receptors (c erb A proteins). We have shown that: a) T3 stimulates the turnover of nuclear proteins, with a more evident effect on the non-histone component; b) for the whole lifespan of cultures the predominant form of c erb A mRNA is the 2 variant (which encodes a protein unable to bind T3); whatever the function of 2 protein this finding suggests that its predominance on 1 is settled very early during mammalian brain maturation. |
