title: Protein complex formation and intranuclear dynamics of NAC1 in cancer cells.
abstract: Nucleus accumbens-associated protein 1 (NAC1) is a cancer-related transcription regulator protein that is also involved in the pluripotency and differentiation of embryonic stem cells. NAC1 is overexpressed in various carcinomas including ovarian, cervical, breast, and pancreatic carcinomas. NAC1 knock-down was previously shown to result in the apoptosis of ovarian cancer cell lines and to rescue their sensitivity to chemotherapy, suggesting that NAC1 may be a potential therapeutic target, but protein complex formation and the dynamics of intranuclear NAC1 in cancer cells remain poorly understood. In this study, analysis of HeLa cell lysates by fast protein liquid chromatography (FPLC) on a sizing column showed that the NAC1 peak corresponded to an apparent molecular mass of 300-500 kDa, which is larger than the estimated molecular mass (58 kDa) of the protein. Furthermore, live cell photobleaching analyses with green fluorescent protein (GFP)-fused NAC1 proteins revealed the intranuclear dynamics of NAC1. Collectively our results demonstrate that NAC1 forms a protein complex to function as a transcriptional regulator in cancer cells.
authors.affiliation: Department of Biochemistry, Shimane University School of Medicine, Izumo 693-8501, Japan.
authors.forename: Naomi
authors.initials: N
authors.lastname: Nakayama
authors.affiliation: Department of Biochemistry, Shimane University School of Medicine, Izumo 693-8501, Japan.
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Kato
authors.affiliation: Department of Biochemistry, Shimane University School of Medicine, Izumo 693-8501, Japan.
authors.forename: Gyosuke
authors.initials: G
authors.lastname: Sakashita
authors.affiliation: Department of Biochemistry, Shimane University School of Medicine, Izumo 693-8501, Japan.
authors.forename: Yuko
authors.initials: Y
authors.lastname: Nariai
authors.affiliation: Department of Obstetrics and Gynecology, Shimane University School of Medicine, Izumo 693-8501, Japan.
authors.forename: Kentaro
authors.initials: K
authors.lastname: Nakayama
authors.affiliation: Department of Obstetrics and Gynecology, Shimane University School of Medicine, Izumo 693-8501, Japan.
authors.forename: Satoru
authors.initials: S
authors.lastname: Kyo
authors.affiliation: Department of Biochemistry, Shimane University School of Medicine, Izumo 693-8501, Japan. Electronic address: turano@med.shimane-u.ac.jp.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Urano
mesh_terms: D002467:Cell Nucleus / Q000378:metabolism; D002843:Chromatin / Q000378:metabolism; D002851:Chromatography, High Pressure Liquid; D004058:Diffusion; D036681:Fluorescence Recovery After Photobleaching; D049452:Green Fluorescent Proteins / Q000737:chemistry; D006367:HeLa Cells; D006657:Histones / Q000737:chemistry; D006801:Humans; D007700:Kinetics; D008970:Molecular Weight; D009363:Neoplasm Proteins / Q000235:genetics* / Q000378:metabolism*; D009369:Neoplasms / Q000378:metabolism*; D011485:Protein Binding; D000072417:Protein Domains; D055503:Protein Multimerization; D012097:Repressor Proteins / Q000235:genetics* / Q000378:metabolism*
chemical_list: D002843:Chromatin; D006657:Histones; C516477:NACC1 protein, human; D009363:Neoplasm Proteins; D012097:Repressor Proteins; D049452:Green Fluorescent Proteins
keywords: Fluorescence loss in photobleaching (FLIP); Fluorescence recovery after photobleaching (FRAP); Intranuclear dynamics; Live cell photobleaching analysis; Nucleus accumbens-associated protein 1 (NAC1); Protein complex formation