title: Recruitment of NBS1 into PML oncogenic domains via interaction with SP100 protein.
abstract: Nijmegen breakage syndrome (NBS) is an autosomal recessive disorder characterized by microcephaly, chromosomal instability, radiation sensitivity, and an increased incidence of malignancies. NBS1, the protein responsible for NBS, forms a complex with MRE11 and RAD50, and plays a vital role in DNA repair, cell cycle checkpoint, and telomere maintenance. Here, we show that a BRCA carboxyl terminus (BRCT) domain-containing region of NBS1 interacts with a nuclear dots-associated protein, SP100. The SP100 and NBS1 proteins co-localized in PODs and APBs in normal human fibroblast MRC5 and ALT line VA13 at G2 phase, respectively. Introduction of PML and SP100 into NT2 cells, which express no detectable amount of PML or SP100 proteins, resulted in localization of NBS1 in ectopically expressed PODs. These results indicate that NBS1 is recruited into PODs via interaction with SP100 protein. Thus, interaction between the NBS1 and SP100 proteins may be involved in genomic stability and telomere maintenance.
authors.affiliation: Department of Geriatric Research, National Institute for Longevity Sciences, 36-3 Gengo, Morioka, Obu, Aichi 474-8522, Japan.
authors.forename: Kazuhito
authors.initials: K
authors.lastname: Naka
authors.forename: Kyoji
authors.initials: K
authors.lastname: Ikeda
authors.forename: Noboru
authors.initials: N
authors.lastname: Motoyama
mesh_terms: D000818:Animals; D034961:Antigens, Nuclear; D018797:Cell Cycle Proteins / Q000032:analysis / Q000737:chemistry / Q000378:metabolism*; D002461:Cell Line, Transformed; D002467:Cell Nucleus / Q000737:chemistry; D002478:Cells, Cultured; D004268:DNA-Binding Proteins; D016195:G2 Phase; D006801:Humans; D008856:Microscopy, Fluorescence; D009363:Neoplasm Proteins / Q000032:analysis; D009687:Nuclear Proteins / Q000032:analysis / Q000737:chemistry / Q000378:metabolism*; D015513:Oncogene Proteins / Q000032:analysis; D000071156:Promyelocytic Leukemia Protein; D017434:Protein Structure, Tertiary; D021381:Protein Transport; D016615:Telomere; D014157:Transcription Factors / Q000032:analysis; D025521:Tumor Suppressor Proteins; D020798:Two-Hybrid System Techniques
chemical_list: D034961:Antigens, Nuclear; D018797:Cell Cycle Proteins; D004268:DNA-Binding Proteins; D009363:Neoplasm Proteins; C466108:Nijmegen breakage syndrome 1 protein, mouse; D009687:Nuclear Proteins; D015513:Oncogene Proteins; C513293:Pml protein, mouse; D000071156:Promyelocytic Leukemia Protein; C092315:Sp100 protein, mouse; D014157:Transcription Factors; D025521:Tumor Suppressor Proteins; C070576:PML protein, human