First Author | Huang Z | Year | 2012 |
Journal | J Comp Neurol | Volume | 520 |
Issue | 6 | Pages | 1227-45 |
PubMed ID | 21935948 | Mgi Jnum | J:183955 |
Mgi Id | MGI:5319598 | Doi | 10.1002/cne.22772 |
Citation | Huang Z, et al. (2012) Loss of neural recognition molecule NB-3 delays the normal projection and terminal branching of developing corticospinal tract axons in the mouse. J Comp Neurol 520(6):1227-45 |
abstractText | Neural recognition molecule NB-3 is involved in neural development and synapse formation. However, its role in axon tract formation is unclear. In this study, we found that the temporal expression of NB-3 in the deep layers of the motor cortex in mice was coincident with the development of the corticospinal tract (CST). Clear NB-3 immunoreactivity in the CST trajectory strongly suggested that NB-3 was expressed specifically in projecting CST axons. By tracing CST axons in NB-3-/- mice at different developmental stages, we found that these axons were capable of projecting and forming a normal trajectory. However, the projection was greatly delayed in NB-3-/- mice compared with wild-type (WT) mice from the embryonic to postnatal stages, a period that is coincident with the completion of the CST projection in mice. Subsequently, although their projection was delayed, CST axons in NB-3-/- mice gradually completed a normal projection. By stage P21, the characteristics of CST projections in NB-3-/- mice were not statistically different from those in WT mice. In addition, we found that the branching of CST axons into spinal gray matter also was delayed in NB-3-/- mice. The CST innervation area in the spinal gray matter of NB-3-/- mice was greatly reduced in comparison with WT mice until P30 and gradually became normal by P45. These data suggest that NB-3 is involved in the normal projection and terminal branching of developing CST axons. |