title: Association of p21 with NF-YA suppresses the expression of Polo-like kinase 1 and prevents mitotic death in response to DNA damage.
abstract: Polo-like kinase 1 (PLK1) is an important mitotic kinase and its expression is tightly regulated in the cell cycle and in the DNA damage response. PLK1 expression is previously shown to be suppressed by p53 and/or p21. Here, we demonstrate that the CCAAT box in the PLK1 promoter is pivotal for p53/p21-mediated PLK1 repression. Chromatin immunoprecipitation showed that cyclin-dependent kinase 2 (CDK2) associated with the CCAAT box-containing region of PLK1 promoter in unstressed cells, whereas adriamycin (ADR) induced the recruitment of p21 with a concomitant reduction in the occupancy of CDK2 in this region. Expression of p21 inhibited the interaction between CDK2 and the nuclear factor YA (NF-YA) subunit of the CCAAT box-binding transcription factor NF-Y. A mutant p21 that is defective in CDK2 binding was unable to disrupt the CDK2-NF-YA interaction or suppress PLK1 transcription. Co-immunoprecipitation experiments demonstrated the interaction between NF-YA and p21, and in vitro assays showed that p21 could directly bind to NF-YA. Knockdown of NF-YA decreased the amount of PLK1 promoter-associated p21 and abolished p21-mediated PLK1 repression in cells treated with ADR. Depletion of NF-YA diminished the p53-regulated transcriptional activation and suppressed the p53-mediated protection from mitotic death after DNA damage, and these effects of NF-YA deletion were alleviated by PLK1 depletion. Our findings have uncovered a novel p21/NF-YA/PLK1 axis critical for maintaining the checkpoint function of p53 to prevent mitotic death in the DNA damage-induced response.
authors.affiliation: Institute of Biochemistry and Molecular Biology, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Y-C
authors.initials: YC
authors.lastname: Lin
authors.affiliation: Institute of Biochemistry and Molecular Biology, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Y-N
authors.initials: YN
authors.lastname: Chen
authors.affiliation: Institute of Biochemistry and Molecular Biology, National Yang-Ming University, Taipei, Taiwan.
authors.forename: K-F
authors.initials: KF
authors.lastname: Lin
authors.affiliation: Institute of Biochemistry and Molecular Biology, National Yang-Ming University, Taipei, Taiwan.
authors.forename: F-F
authors.initials: FF
authors.lastname: Wang
authors.affiliation: 1] Institute of Biochemistry and Molecular Biology, National Yang-Ming University, Taipei, Taiwan [2] Institute of Clinical Medicine, National Yang-Ming University, Taipei, Taiwan [3] Department of Pathology and Laboratory Medicine, Taipei Veterans General Hospital, Taipei, Taiwan.
authors.forename: T-Y
authors.initials: TY
authors.lastname: Chou
authors.affiliation: 1] Institute of Biochemistry and Molecular Biology, National Yang-Ming University, Taipei, Taiwan [2] Cancer Research Center and Genome Research Center, National Yang-Ming University, Taipei, Taiwan.
authors.forename: M-Y
authors.initials: MY
authors.lastname: Chen
mesh_terms: D017209:Apoptosis; D023081:CCAAT-Binding Factor / Q000235:genetics / Q000378:metabolism*; D018797:Cell Cycle Proteins / Q000235:genetics* / Q000378:metabolism; D002460:Cell Line; D051357:Cyclin-Dependent Kinase 2 / Q000235:genetics / Q000378:metabolism; D050759:Cyclin-Dependent Kinase Inhibitor p21 / Q000235:genetics / Q000378:metabolism*; D004249:DNA Damage; D015536:Down-Regulation; D006801:Humans; D008938:Mitosis; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D017346:Protein Serine-Threonine Kinases / Q000235:genetics* / Q000378:metabolism; D011518:Proto-Oncogene Proteins / Q000235:genetics* / Q000378:metabolism; D015533:Transcriptional Activation; D016159:Tumor Suppressor Protein p53 / Q000235:genetics / Q000378:metabolism; D000097869:Polo-Like Kinase 1
chemical_list: D023081:CCAAT-Binding Factor; D018797:Cell Cycle Proteins; D051357:Cyclin-Dependent Kinase 2; D050759:Cyclin-Dependent Kinase Inhibitor p21; D017346:Protein Serine-Threonine Kinases; D011518:Proto-Oncogene Proteins; D016159:Tumor Suppressor Protein p53; D000097869:Polo-Like Kinase 1; C492061:NFYA protein, human; C495894:CDK2 protein, human