Neuron-intrinsic inhibitors of axon regeneration: PTEN and SOCS3.

Our understanding of how axon regeneration is controlled in both the peripheral and central nervous systems remains fragmentary. Research into the regenerative capacity of adult neurons has elucidated PTEN and SOCS3 as distinctive but complementary arms of the regenerative program. These molecules act as negative regulators of major signaling pathways and impact the processes occurring in the cell body, such as protein translation and transcription, and in the axons, such as cytoskeleton assembly. In this review, we summarize the role of PTEN and SOCS3 in limiting axon regeneration and discuss the molecular and cellular mechanisms underlying their growth-inhibitory effects.