No Nogo: now where to go?

Nogo-A, a reticulon protein expressed by oligodendrocytes, contributes to the axonal growth inhibitory action of central myelin in growth cone collapse and neurite outgrowth in vitro assays, and antibody and inhibitor studies have implicated a role for Nogo in regeneration in the adult CNS in vivo. Three independent labs have now produced Nogo knockout mice with, quite unexpectedly, three different regeneration phenotypes.