PT - JOURNAL ARTICLE AU - William B. J. Cafferty AU - Stephen M. Strittmatter TI - The Nogo–Nogo Receptor Pathway Limits a Spectrum of Adult CNS Axonal Growth AID - 10.1523/JNEUROSCI.3827-06.2006 DP - 2006 Nov 22 TA - The Journal of Neuroscience PG - 12242--12250 VI - 26 IP - 47 4099 - http://www.jneurosci.org/content/26/47/12242.short 4100 - http://www.jneurosci.org/content/26/47/12242.full SO - J. Neurosci.2006 Nov 22; 26 AB - The hypothesis that Nogo-A (Reticulon 4A) and Nogo-66 receptor (NgR1) limit adult CNS axonal growth after injury is supported by both in vitro experiments and in vivo pharmacological studies. However, genetic assessment of the role of Nogo-A in corticospinal tract (CST) axons after spinal cord dorsal hemisection has yielded conflicting results. CST regeneration is detected in homozygous nogo-abtrap/trap mice, but not in nogo-abatg/atg mice. CST regeneration is also present after pharmacological NgR blockade, but not in ngr1 −/− mice. To assess the nogo-abatg and ngr1-null alleles for other axon growth phenotypes, we created unilateral pyramidotomies and monitored the uninjured CST. There is robust pyramidotomy-induced growth of nogo-abatg/atg and ngr1 −/− CST axons into denervated cervical gray matter. This fiber growth correlates with recovery of fine motor skill in the affected forelimb. Thus nogo-ab and ngr1 play a modulated role in limiting CNS axonal growth across a spectrum of different tracts in various lesion models.