title: Mapmodulin/leucine-rich acidic nuclear protein binds the light chain of microtubule-associated protein 1B and modulates neuritogenesis.
abstract: We had previously described the leucine-rich acidic nuclear protein (LANP) as a candidate mediator of toxicity in the polyglutamine disease, spinocerebellar ataxia type 1 (SCA1). This was based on the observation that LANP binds ataxin-1, the protein involved in this disease, in a glutamine repeat-dependent manner. Furthermore, LANP is expressed abundantly in purkinje cells, the primary site of ataxin-1 pathology. Here we focused our efforts on understanding the neuronal properties of LANP. In undifferentiated neuronal cells LANP is predominantly a nuclear protein, requiring a bona fide nuclear localization signal to be imported into the nucleus. LANP translocates from the nucleus to the cytoplasm during the process of neuritogenesis, interacts with the light chain of the microtubule-associated protein 1B (MAP1B), and modulates the effects of MAP1B on neurite extension. LANP thus could play a key role in neuronal development and/or neurodegeneration by its interactions with microtubule associated proteins.
authors.affiliation: Department of Neurology, Baylor College of Medicine, Houston, Texas 77030, USA. p-opal@northwestern.edu
authors.forename: Puneet
authors.initials: P
authors.lastname: Opal
authors.forename: Jesus J
authors.initials: JJ
authors.lastname: Garcia
authors.forename: Friedrich
authors.initials: F
authors.lastname: Propst
authors.forename: Antoni
authors.initials: A
authors.lastname: Matilla
authors.forename: Harry T
authors.initials: HT
authors.lastname: Orr
authors.forename: Huda Y
authors.initials: HY
authors.lastname: Zoghbi
mesh_terms: D000818:Animals; D002454:Cell Differentiation; D002467:Cell Nucleus / Q000378:metabolism*; D003593:Cytoplasm / Q000378:metabolism; D005973:Glutamine / Q000737:chemistry; D006801:Humans; D051379:Mice; D008856:Microscopy, Fluorescence; D008869:Microtubule-Associated Proteins / Q000737:chemistry* / Q000378:metabolism; D008870:Microtubules / Q000378:metabolism; D009474:Neurons / Q000166:cytology / Q000378:metabolism*; D009479:Neuropeptides / Q000378:metabolism* / Q000502:physiology*; D009687:Nuclear Proteins / Q000378:metabolism* / Q000502:physiology*; D011233:Precipitin Tests; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D021381:Protein Transport; D011689:Purkinje Cells; D020754:Spinocerebellar Ataxias / Q000378:metabolism; D014162:Transfection; D014407:Tumor Cells, Cultured; D020798:Two-Hybrid System Techniques
chemical_list: C490341:ANP32B protein, human; D008869:Microtubule-Associated Proteins; D009479:Neuropeptides; D009687:Nuclear Proteins; C085284:microtubule-associated protein 1B; D005973:Glutamine