title: Nogo-A inhibits necdin-accelerated neurite outgrowth by retaining necdin in the cytoplasm.
abstract: Nogo-A has been identified in the central nervous system as an inhibitor for axonal regeneration. Previous works have mainly focused on Nogo-A in oligodendrocytes and the roles of neuronal intracellular Nogo-A remain elusive. To gain deep insight into the physiological functions of Nogo-A, a yeast two-hybrid screening was performed with Nogo-66 as bait. We identified a new interaction between Nogo-66 and necdin. Mutagenesis analysis revealed that the central region of necdin was indispensable for the interaction of necdin with Nogo-66. The interaction was further confirmed by co-immunoprecipitation in neural tissues and cultured cortical neurons. Morphological evidence showed that Nogo-A and necdin highly colocalized in rat cortical and dorsal root ganglia neurons. Ectopic expression of Nogo-A in HEK293 cells led to retention of necdin from the nucleus to the cytoplasm. Furthermore, overexpression of Nogo-A in PC12 cells and cultured cortical neurons inhibited necdin-accelerated neurite outgrowth. Meanwhile, necdin was found to be significantly sequestered in the cytoplasm of PC12 cells stably overexpressing Nogo-A. Together, these data suggest that Nogo-A is a novel necdin binding protein and inhibits necdin-accelerated neuronal neurite outgrowth by sequestering necdin in the cytoplasm.
authors.affiliation: Institute of Neuroscience and Key Laboratory of Molecular Neurobiology, Ministry of Education, SMMU, Shanghai 200433, China.
authors.forename: Xiujie
authors.initials: X
authors.lastname: Liu
authors.forename: Yonggang
authors.initials: Y
authors.lastname: Wang
authors.forename: Yong
authors.initials: Y
authors.lastname: Zhang
authors.forename: Wei
authors.initials: W
authors.lastname: Zhu
authors.forename: Xiaohui
authors.initials: X
authors.lastname: Xu
authors.forename: Michio
authors.initials: M
authors.lastname: Niinobe
authors.forename: Kazuaki
authors.initials: K
authors.lastname: Yoshikawa
authors.forename: Changlin
authors.initials: C
authors.lastname: Lu
authors.forename: Cheng
authors.initials: C
authors.lastname: He
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002478:Cells, Cultured; D003593:Cytoplasm / Q000378:metabolism*; D006801:Humans; D008297:Male; D008969:Molecular Sequence Data; D009185:Myelin Proteins / Q000235:genetics / Q000378:metabolism*; D009416:Nerve Regeneration / Q000502:physiology; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000378:metabolism*; D016501:Neurites / Q000502:physiology*; D009474:Neurons / Q000166:cytology / Q000378:metabolism; D000070798:Nogo Proteins; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism*; D016716:PC12 Cells; D051381:Rats; D017207:Rats, Sprague-Dawley; D016415:Sequence Alignment; D020798:Two-Hybrid System Techniques
chemical_list: D009185:Myelin Proteins; D009419:Nerve Tissue Proteins; D000070798:Nogo Proteins; D009687:Nuclear Proteins; C000603199:RTN4 protein, human; C000603197:Rtn4 protein, rat; C069766:necdin