Inhibitor of neurite outgrowth in humans

Axons are generally believed to be incapable of regeneration in the adult central nervous system. Inhibition results from physical barriers imposed by glial scars, a lack of neurotrophic factors, and growth-inhibitory molecules associated with myelin, the insulating axon sheath. These molecules include proteoglycans, myelin-associated glycoprotein and, in bovine brain, two proteins called Nogo. We have used this bovine sequence to identify the human Nogo gene and have isolated complementary DNA clones encoding three different Nogo isoforms that are potent inhibitors of neurine outgrowth and which may help block the regeneration of the central nervous system in adults.