NERVE GROWTH-FACTOR PROMOTES NEURITE REGENERATION IN PC12 CELLS BY TRANSLATIONAL CONTROL

When PC12 cells are primed with nerve growth factor (NGF) for periods of greater than or equal to 1 week, they acquire the ability to regene rate neurites rapidly in response to NGF. It is not known how NGF prom otes this regeneration, but it does not require ongoing RNA synthesis. Previous studies have suggested that NGF directs the accumulation of precursor molecules that are rapidly assembled to form the regenerated neurites. To address the nature of these precursor molecules, we have treated PC12 cells with macromolecular synthesis inhibitors during th e priming and regeneration phases of neurite growth. Here we show that NGF promotes neurite regeneration by inducing the synthesis of new pr oteins. These proteins are encoded by short-lived mRNAs that are gener ated during the NGF priming period. The isolation and identification o f these mRNAs will allow a further understanding of how NGF promotes n eurite regeneration.