CENP-Bは,染色体の文脈によって,センターメア形成を制御する
Teruaki Okada1, Jun-ichirou Ohzeki, Megumi Nakano
1Division of Biological Science, Graduate School of Science, Nagoya University, Chikusa-ku, Nagoya 464-8602, Japan.
Cell
|December 28, 2007
まとめ
セントロメア組立には,CENP-Bタンパク質が必要です. このタンパク質は,人工染色体上の新しいセントロメア形成を促しますが,ヘテロクロマチンを促進することにより,既存の染色体上の余分なセントロメアを防止します.
科学分野:
- * 分子生物学 * 分子生物学
- * エピジェネティクス
- *染色体生物学について
背景:
- * セントロメアは,細胞分裂中の正確な染色体分離に不可欠です.
- * セントロメア組立と安定化を制御する正確なメカニズムは,まだ完全に理解されていません.
- *アルファ衛星DNAとCENP-Bタンパク質は,セントロメア形成に関与することが知られている.
研究 の 目的:
- * 人/哺乳類人工染色体 (HAC/MAC) の新型セントロメア組立におけるCENP-Bの役割を明らかにする.
- *アルファ衛星DNAが既存の染色体部位に統合されたとき,セントロメア形成に対するCENP-Bの効果を調査する.
- * セントロメア形成の調節におけるCENP-Bの二重機能を理解する.
主な方法:
- * アルファ衛星DNAを統合したヒト/哺乳類人工染色体 (HAC/MAC) の構築と分析.
- * 細胞系におけるCENP-Bを含む遺伝子発現の研究.
- *ヒストンH3-K9トリメチル化およびDNAメチル化を含む表遺伝的変化の評価.
主要な成果:
- * HAC/MACのデノボ・セントロメア組成は,CENP-B.の存在に依存しています.
- * CENP-Bは染色体統合部位におけるセントロメア形成を抑制する.
- * CENP-Bは統合部位でヘテロクロマチンの形成 (ヒストンH3-K9トリメチル化とDNAメチル化) を促進する.
結論:
- * CENP-Bは,センターメア形成において重要な二重の役割を果たします.
- * 欠けているDNAに新しいセントロメアの形成を促す.
- * ヘテロクロマチンの形成を促すことで,既存の染色体上の異胎性または過剰なセントロメアの形成を防ぐ.
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