考察

作用し、コヒーシンの位置取りを正すことが姉妹染色体の不分離を防ぐことも 考えられる。

これらのことを調べるために H2A.Z の過剰発現やユビキチン化されない

H2A.Zの変異体を作製し、DNA修復や染色体構造にどのような影響を与えるか

分析する必要がある。また、Figure 8 における結果がモデルと一致しているか 調べるため、免疫沈降を行う必要がある。

5 結論

本研究によりRNF４によってユビキチン化を受ける基質を同定した。さらに RNF4 欠損細胞において H2A.Z の蓄積がみられた。プロテアソーム阻害剤

MG132、タンパク質合成阻害剤シクロへキシミドによってH2A.Zのタンパク質

量に変化がみられたことからH2A.ZはRNF4によってプロテアソーム分解され ていることが示唆された。

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