title: CALEB/NGC interacts with the Golgi-associated protein PIST.
abstract: CALEB/NGC is a neural member of the epidermal growth factor protein family expressed in axon and synapse-rich areas of the nervous system and shown to be important for neurite formation. It can bind to the extracellular matrix proteins tenascin-R and tenascin-C. Here we show that CALEB/NGC interacts with the Golgi-associated protein PIST. PIST was originally described as an interaction partner of the small GTPase TC10 and was then found to be Golgi-associated by binding to syntaxin-6 and to be important for the transport of frizzled proteins and the cystic fibrosis transmembrane conductance regulator to the plasma membrane. In addition, PIST was demonstrated to be involved in autophagy and linked to processes of neurodegeneration. CALEB/NGC interacts with PIST in the yeast two-hybrid system. This interaction can be confirmed by co-immunoprecipitations and co-localization studies. The juxtamembrane cytoplasmic peptide segment of CALEB/NGC, highly conserved during evolution, mediates the binding to PIST. CALEB/NGC co-localizes with PIST in the Golgi apparatus of transfected COS7 cells and in Golgi-derived vesicles after brefeldin A or nocodazole treatment. Co-localization studies in primary hippocampal cells and analysis of Purkinje cells of colchicine-treated rats, serving as an in vivo model system to block microtubule-dependent transport processes, support the view that PIST is an interaction partner of CALEB/NGC and implicate that this interaction may play a role in the intracellular transport of CALEB/NGC.
authors.affiliation: Institut für Zellbiochemie und Klinische Neurobiologie, Universitätsklinikum Hamburg-Eppendorf, Martinistrasse 52, D-20246 Hamburg, Germany.
authors.forename: Burkhard
authors.initials: B
authors.lastname: Hassel
authors.forename: Matthias
authors.initials: M
authors.lastname: Schreff
authors.forename: Eva-Maria
authors.initials: EM
authors.lastname: Stube
authors.forename: Uta
authors.initials: U
authors.lastname: Blaich
authors.forename: Stefan
authors.initials: S
authors.lastname: Schumacher
mesh_terms: D048868:Adaptor Proteins, Signal Transducing; D000818:Animals; D030161:Avian Proteins / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D001921:Brain / Q000378:metabolism; D019556:COS Cells; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism*; D002460:Cell Line; D002645:Chickens; D003078:Colchicine / Q000494:pharmacology; D018076:DNA, Complementary / Q000235:genetics; D004815:Epidermal Growth Factor / Q000235:genetics / Q000378:metabolism*; D006056:Golgi Apparatus / Q000378:metabolism*; D000077614:Golgi Matrix Proteins; D006624:Hippocampus / Q000378:metabolism; D006801:Humans; D066298:In Vitro Techniques; D008562:Membrane Glycoproteins / Q000235:genetics / Q000378:metabolism*; D008565:Membrane Proteins; D026901:Membrane Transport Proteins; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000378:metabolism*; D011689:Purkinje Cells / Q000187:drug effects / Q000378:metabolism; D051381:Rats; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D014162:Transfection; D020798:Two-Hybrid System Techniques
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D030161:Avian Proteins; C104596:CALEB protein, chicken; D002352:Carrier Proteins; D018076:DNA, Complementary; C434484:GOPC protein, human; C575136:GOPC protein, rat; D000077614:Golgi Matrix Proteins; D008562:Membrane Glycoproteins; D008565:Membrane Proteins; D026901:Membrane Transport Proteins; D009419:Nerve Tissue Proteins; D011994:Recombinant Proteins; D004815:Epidermal Growth Factor; D003078:Colchicine