人間のテロメア末端トランスファーゼ酵素は,TTAGGGの繰り返しを合成するリボヌクレオプロテインです
1Department of Molecular Biophysics and Biochemistry, Howard Hughes Medical Institute, Yale University, New Haven, Connecticut 06510.
Cell
|November 3, 1989
まとめ
研究者らは,ヒトのテロメラーゼをHeLa細胞で発見し,テロメアにDNAの繰り返し配列を追加する酵素である. この発見は,テロメアの維持が,原生動物から人間まで,エウカリオット全体で保存されていることを示しています.
科学分野:
- 分子生物学は分子生物学である.
- 遺伝学 遺伝学とは
- 細胞生物学 細胞生物学
背景:
- テロメアは,真核染色体の末端にある保護キャップです.
- テロメラーゼは,リボヌクレオプロテイン酵素であり,テロメアの維持に責任があります.
- 以前は,テロメラーゼは,多くのテロメアを持つ状原生類のような生物で主に観察されていました.
研究 の 目的:
- 人間の細胞抽出物におけるテロメア末端トランスファーゼの活性を特定し,特徴づけること.
- テロメア維持メカニズムがヒト細胞に保存されているかどうかを判断する.
主な方法:
- 酵素活性に対する原始HeLa細胞抽出物の測定.
- テロメア重複配列を用いたオリゴヌクレオチドプライマー拡張.
- 反応産物の直接配列分析. 反応産物の直接配列分析.
主要な成果:
- HeLa細胞抽出物でヒトテロメラーゼ活性が確認されました.
- 酵素がTTAGGGの繰り返し配列の添加を触媒化することを示した.
- 最適な条件下で65〜70回の繰り返しの合成を観察しました.
- 酵素をリボヌクレオプロテインとして特徴付けました.
結論:
- 人間のテロメラーゼ活性がHeLa細胞で特定されています.
- ヒト細胞のテロメラーゼの存在は,原生類よりもテロメアが少ないにもかかわらず,エウカリオート全体でテロメア維持が保存されていることを示しています.
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