title: Interactions of the natural product (+)-avrainvillamide with nucleophosmin and exportin-1 Mediate the cellular localization of nucleophosmin and its AML-associated mutants.
abstract: Nucleophosmin (NPM1) is a multifunctional phosphoprotein localized predominantly within the nucleoli of eukaryotic cells. Mutations within its C-terminal domain are frequently observed in patients with acute myeloid leukemia (AML), are thought to play a key role in the initiation of the disease, and result in aberrant, cytoplasmic localization of the mutant protein. We have previously shown that the electrophilic antiproliferative natural product (+)-avrainvillamide (1) binds to proteins, including nucleophosmin, by S-alkylation of cysteine residues. Here, we report that avrainvillamide restores nucleolar localization of certain AML-associated mutant forms of NPM1 and provide evidence that this relocalization is mediated by interactions of avrainvillamide with mutant NPM1 and exportin-1 (Crm1). Immunofluorescence and mass spectrometric experiments employing a series of different NPM1 constructs suggest that a specific interaction between avrainvillamide and Cys275 of certain NPM1 mutants mediates the relocalization of these proteins to the nucleolus. Avrainvillamide treatment is also shown to inhibit nuclear export of Crm1 cargo proteins, including AML-associated NPM1 mutants. We also observe that avrainvillamide treatment displaces Thr199-phosphorylated NPM1 from duplicated centrosomes, leads to an accumulation of supernumerary centrosomes, and inhibits dephosphorylation of Thr199-phosphorylated NPM1 by protein phosphatase 1. Avrainvillamide is the first small molecule reported to relocalize specific cytoplasmic AML-associated NPM1 mutants to the nucleolus, providing an important demonstration of principle that small molecule induction of a wild-type NPM1 localization phenotype is feasible in certain human cancer cells.
authors.affiliation: †Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, United States.
authors.forename: Herschel
authors.initials: H
authors.lastname: Mukherjee
authors.affiliation: †Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, United States.
authors.forename: Kok-Ping
authors.initials: KP
authors.lastname: Chan
authors.affiliation: ‡Centre for Cancer Biomarkers, CCBIO, Department of Clinical Science, University of Bergen, Bergen, Norway.
authors.forename: Vibeke
authors.initials: V
authors.lastname: Andresen
authors.affiliation: †Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, United States.
authors.forename: Mariah L
authors.initials: ML
authors.lastname: Hanley
authors.affiliation: ‡Centre for Cancer Biomarkers, CCBIO, Department of Clinical Science, University of Bergen, Bergen, Norway.|§Department of Internal Medicine, Hematology Section, Haukeland University Hospital, Bergen, Norway.
authors.forename: Bjørn Tore
authors.initials: BT
authors.lastname: Gjertsen
authors.affiliation: †Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, United States.
authors.forename: Andrew G
authors.initials: AG
authors.lastname: Myers
mesh_terms: D021581:Active Transport, Cell Nucleus; D000970:Antineoplastic Agents / Q000737:chemistry* / Q000494:pharmacology; D001665:Binding Sites; D001688:Biological Products / Q000737:chemistry* / Q000494:pharmacology; D002466:Cell Nucleolus / Q000378:metabolism; D003593:Cytoplasm / Q000378:metabolism; D015972:Gene Expression Regulation, Neoplastic; D045325:HCT116 Cells; D006801:Humans; D007211:Indoles / Q000737:chemistry* / Q000494:pharmacology; D028884:Karyopherins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D009154:Mutation; D009687:Nuclear Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D000090243:Nucleophosmin; D011485:Protein Binding; D054645:Protein Phosphatase 1 / Q000737:chemistry / Q000235:genetics; D017434:Protein Structure, Tertiary; D018160:Receptors, Cytoplasmic and Nuclear / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction; D000097606:Exportin 1 Protein
chemical_list: D000970:Antineoplastic Agents; D001688:Biological Products; D007211:Indoles; D028884:Karyopherins; D009687:Nuclear Proteins; D000090243:Nucleophosmin; D054645:Protein Phosphatase 1; D018160:Receptors, Cytoplasmic and Nuclear; D000097606:Exportin 1 Protein; C000716967:NPM1 protein, human; C480558:avrainvillamide