v-src genes stimulate neurite outgrowth in pheochromocytoma (PC12) variants unresponsive to neurotrophic factors

The NGF‐nonresponsive rat pheochromocytoma PC12 variant nnr5, isolated by Green et al. (J Cell Biol 102:830–843, 1986), responds poorly or not at all to fibroblast growth factor. Transformation of PC‐12nnr5 cells with v–src‐expressing retroviruses results in vigorous neurite outgrowth, similar to that seen in the parent cell line. Thus though the PC12nnr5 cell line has a greatly impaired ability to respond to neurotrophic factors it still may extend neurites. This data is consistent with a model in which PC12nnr5 cells are unable to propagate intracellular second messengers, and this defect may be related to the expression of c‐src gene products.