Cloning and characterization of a novel human ninein protein that interacts with the glycogen synthase kinase 3 beta

Using human glycogen synthase kinase 3 beta (GSK-3 beta) as bait in the yea st two-hybrid system, we identified a novel human centrosome associated pro tein, hNinein. When the full length cDNA of hNinein was sequenced, it showe d that an open reading frame encoded a protein consisting of 2047 amino aci ds with a predicted molecular mass of 239 kDa. The features of this protein include a potential GTP binding site, a large coiled-coil domain together with four leucine zipper domains and a GSK-3 beta binding site. Fluorescenc e microscopy experiment showed that hNinein is localized in the pericentrio lar matrix of the centrosome. In addition, hNinein also showed to react wit h centrosomal autoantibody sera. Our findings suggest that hNinein may be i nvolved in the formation of centrosome matrix and interacts with the GSK3 b eta, implying that it may also be regulated by GSK-3 beta phosphorylation s ignaling. (C) 2000 Elsevier Science B.V. All rights reserved.