イーストの核毛穴の分離
Anton Khmelinskii1, Philipp J Keller, Holger Lorenz
1Zentrum für Molekulare Biologie der Universität Heidelberg, DKFZ-ZMBH Alliance, Im Neuenheimer Feld 282, D-69120 Heidelberg, Germany.
Nature
|July 24, 2010
まとめ
エクストラクロモソームリボソームDNA円 (ERC) は,酵母菌ミトーシス中の母細胞に留まっています. 提案されたモデルとは対照的に,核孔複合体 (NPC) は子細胞に効率的に移行し,NPCがERC保持を媒介しないことを示唆しています.
科学分野:
- 細胞生物学 細胞生物学
- 分子生物学は分子生物学である.
- 遺伝学 遺伝学とは
背景:
- Saccharomyces cerevisiaeのミトーシス中に,染色体外リボソームDNA円 (ERC) のような老化因子は,母細胞に優先的に留まっています.
- 以前のモデルでは,ERCが核孔複合体 (NPC) と結合して分離し,母細胞に留まることを提案していた.
研究 の 目的:
- イーストミトーシス中の染色体外リボソームDNAサークル (ERC) 分離のメカニズムを調査する.
- 核毛孔複合体 (NPC) が母細胞に留まると,子細胞からのERC排除を媒介するという仮説を検証する.
主な方法:
- 核孔複合体 (NPC) を視覚化および追跡するための顕微鏡技術,Saccharomyces cerevisiae.のミトーシス過程における核孔複合体 (NPC) を視覚化および追跡する技術.
- ミトーシス後の母細胞と子細胞間のNPC分布の分析.
主要な成果:
- 核孔複合体 (NPC) は,ミトーシス中に母細胞から芽に効率的に移動することが示されています.
- この発見は,母細胞におけるNPC保持を,染色体外リボソームDNA円 (ERC) 分離のメカニズムとして提案するモデルと矛盾している.
結論:
- 核毛孔複合体 (NPC) との結合は,Saccharomyces cerevisiae mitosisの間に母細胞内のクロモソーム外リボソームDNA円 (ERC) の保持に責任のあるメカニズムではないようです.
- 酵母におけるERCの非対称的な分離には,代替メカニズムが必要である.
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