Objective Tyro-3 and Axl receptors are expressed in brain in a region-specific manner and their bioactivities in the central nervous system remain still elusive.The aim of the present study was to investigate their functions in neuronal differentiation.Methods PC12 cells overexpressing Tyro-3 or Axl were established by transfection with full-length CMV-Tyro3-eCFP or CMV-Axl-eGFP plasmid,respectively.CMV-eGFP plasmid served as a control vector.After that,the fluorescence intensity and distributions of green fluorescent protein (GFP) and cyan fluorescent protein (CFP) in the cells with or without nerve growth factor (NGF) treatment were real-time monitored.Results Expressions of Tyro-3 and Axl receptors were under the regulation of NGF and associated with neuronal differentiation.This was not observed in CMV-eGFP-transfected PC12 cells.Besides,confocal microscopy revealed that NGF affected intracellular localization of full-length Axl-eGFP and Tyro-3eCFP in PC12 cells.Moreover,the development of outgrowth of differentiated PC12 cells under stimulation of NGF was promoted by overexpression of Tyro-3 or Axl.Conclusion Expressions of Tyro-3 and Axl receptors are under the regulation of NGF and are involved in NGF-induced neuronal differentiation of PC12 cells.