Calcium depletion destabilises kinetochore fibres by the removal of CENP-F from the kinetochore

Phengchat, R., Takata, H., Uchiyama, S. et al. Calcium depletion destabilises kinetochore fibres by the removal of CENP-F from the kinetochore. Sci Rep 7, 7335 (2017). https://doi.org/10.1038/s41598-017-07777-6

H1.X with different properties from other linker histones is required for mitotic progression

AbstractWe report here the characterization of H1.X, a human histone H1 subtype. We demonstrate that H1.X accumulates in the nucleolus during interphase and is distributed at the chromosome periphery during mitosis. In addition, the results of fluorescence recovery after photobleaching indicate that the exchange of H1.X on and off chromatin is faster than that of the other H1 subtypes. Furthermore, RNA interference experiments reveal that H1.X is required for chromosome alignment and segregation. Our results suggest that H1.X has important functions in mitotic progression, which are different from those of the other H1 subtypes

Nucleolin functions in nucleolus formation and chromosome congression

Ma N., Matsunaga S., Takata H., et al. Nucleolin functions in nucleolus formation and chromosome congression. Journal of Cell Science, 120, 12, 2091. https://doi.org/10.1242/jcs.008771

A comparison of dust concentration with high resolution analysis and visible strata in the Holocene and Last Glacial Maximum periods from the Dome Fuji ice core, East Antarctica

第3回極域科学シンポジウム　横断セッション「海・陸・氷床から探る後期新生代の南極寒冷圏環境変動」11月26日（月）、27日（火） ２階ラウン

Chromosome Scaffold is a Double-Stranded Assembly of Scaffold Proteins

Poonperm, R., Takata, H., Hamano, T. et al. Chromosome Scaffold is a Double-Stranded Assembly of Scaffold Proteins. Sci Rep 5, 11916 (2015). https://doi.org/10.1038/srep11916

Calcium ions function as a booster of chromosome condensation

Phengchat, R., Takata, H., Morii, K. et al. Calcium ions function as a booster of chromosome condensation. Sci Rep 6, 38281 (2016). https://doi.org/10.1038/srep38281

Human metaphase chromosome consists of randomly arranged chromatin fibres with up to 30-nm diameter

Wako, T., Yoshida, A., Kato, J. et al. Human metaphase chromosome consists of randomly arranged chromatin fibres with up to 30-nm diameter. Sci Rep 10, 8948 (2020). https://doi.org/10.1038/s41598-020-65842-z

PHB2 Protects Sister-Chromatid Cohesion in Mitosis

SummaryCohesion between sister chromatids is essential for proper chromosome segregation in mitosis. In vertebrate mitotic cells, most cohesin is removed from the chromosome arms [1–4], but centromeric cohesin is protected by shugoshin until the onset of anaphase [5]. However, the mechanism of this protection of centromeric cohesion is not well understood. Here, we demonstrate that prohibitin 2 (PHB2) is involved in the regulation of sister-chromatid cohesion during mitosis in HeLa cells. PHB2 is an evolutionarily conserved protein in eukaryotes and has multiple functions, such as transcriptional regulation and cell viability and development [6–8]. However, its functions in mitosis have not yet been determined. We show that depletion of PHB2 by RNA interference (RNAi) causes premature sister-chromatid separation and defects in chromosome congression accompanied by mitotic arrest by spindle-checkpoint activation. In the absence of PHB2, cohesin is dissociated from centromeres during early mitosis, although the centromeric localization of shugoshin is preserved. Thus, our findings suggest that, in addition to the shugoshin, PHB2 is also required to protect the centromeric cohesion from phosphorylation by Plk1 during early mitosis and that its function is essential for proper mitotic progression

南極ドームふじ深層掘削孔の検層における液温測定値の評価と補正

第6回極域科学シンポジウム[OM] 極域気水圏11月16日（月）　国立極地研究所１階交流アトリウ