RT Journal Article SR Electronic T1 The Nogo–Nogo Receptor Pathway Limits a Spectrum of Adult CNS Axonal Growth JF The Journal of Neuroscience JO J. Neurosci. FD Society for Neuroscience SP 12242 OP 12250 DO 10.1523/JNEUROSCI.3827-06.2006 VO 26 IS 47 A1 William B. J. Cafferty A1 Stephen M. Strittmatter YR 2006 UL http://www.jneurosci.org/content/26/47/12242.abstract 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.