title: Receptor-like protein-tyrosine phosphatase α enhances cell surface expression of neural adhesion molecule NB-3.
abstract: Neural adhesion molecule NB-3 plays an important role in the apical dendrite development of layer V pyramidal neurons in the visual cortex, and receptor-like protein-tyrosine phosphatase α (PTPα) mediates NB-3 signaling in this process. Here we investigated the role of PTPα in regulating cell surface expression of NB-3. We found that cortical neurons from PTPα knock-out mice exhibited a lower level of NB-3 at the cell surface. When expressed in COS1 cells, NB-3 was enriched in the Golgi apparatus with a low level of cell surface expression. However, co-expression of PTPα increased the cell surface distribution of NB-3. Further analysis showed that PTPα facilitated Golgi exit of NB-3 and stabilized NB-3 protein at the cell surface by preventing its release from the plasma membrane. The extracellular region of PTPα but not its catalytic activity is necessary for its effect on NB-3 expression. Thus, the PTPα-mediated increase of NB-3 level at the cell surface represents a novel function of PTPα in NB-3 signaling in neural development.
authors.affiliation: State Key Laboratory of Brain and Cognitive Sciences, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China. yehaihong@gmail.com
authors.forename: Haihong
authors.initials: H
authors.lastname: Ye
authors.forename: Tian
authors.initials: T
authors.lastname: Zhao
authors.forename: Yen Ling Jessie
authors.initials: YL
authors.lastname: Tan
authors.forename: Jianghong
authors.initials: J
authors.lastname: Liu
authors.forename: Catherine J
authors.initials: CJ
authors.lastname: Pallen
authors.forename: Zhi-Cheng
authors.initials: ZC
authors.lastname: Xiao
mesh_terms: D000818:Animals; D019556:COS Cells; D015816:Cell Adhesion Molecules, Neuronal / Q000096:biosynthesis / Q000378:metabolism*; D002462:Cell Membrane / Q000378:metabolism; D002522:Chlorocebus aethiops; D005110:Extracellular Space / Q000378:metabolism; D005353:Fibronectins / Q000737:chemistry; D005786:Gene Expression Regulation; D006056:Golgi Apparatus / Q000378:metabolism; D006801:Humans; D007136:Immunoglobulins / Q000737:chemistry; D051379:Mice; D009474:Neurons / Q000166:cytology* / Q000378:metabolism*; D055550:Protein Stability; D021381:Protein Transport; D054630:Receptor-Like Protein Tyrosine Phosphatases, Class 4 / Q000737:chemistry / Q000172:deficiency / Q000378:metabolism*; D020449:Repetitive Sequences, Amino Acid; D015398:Signal Transduction; D014162:Transfection
chemical_list: D015816:Cell Adhesion Molecules, Neuronal; D005353:Fibronectins; D007136:Immunoglobulins; C526283:contactin 6 protein, mouse; C516841:PTPRA protein, human; D054630:Receptor-Like Protein Tyrosine Phosphatases, Class 4