ジャーナル: Nat Struct Mol Biol / 年: 2007 タイトル: Architecture of the Dam1 kinetochore ring complex and implications for microtubule-driven assembly and force-coupling mechanisms. 著者: Hong-Wei Wang / Vincent H Ramey / Stefan Westermann / Andres E Leschziner / Julie P I Welburn / Yuko Nakajima / David G Drubin / Georjana Barnes / Eva Nogales / 要旨: The Dam1 kinetochore complex is essential for chromosome segregation in budding yeast. This ten-protein complex self-assembles around microtubules, forming ring-like structures that move with ...The Dam1 kinetochore complex is essential for chromosome segregation in budding yeast. This ten-protein complex self-assembles around microtubules, forming ring-like structures that move with depolymerizing microtubule ends, a mechanism with implications for cellular function. Here we used EM-based single-particle and helical analyses to define the architecture of the Dam1 complex at 30-A resolution and the self-assembly mechanism. Ring oligomerization seems to be facilitated by a conformational change upon binding to microtubules, suggesting that the Dam1 ring is not preformed, but self-assembles around kinetochore microtubules. The C terminus of the Dam1p protein, where most of the Aurora kinase Ipl1 phosphorylation sites reside, is in a strategic location to affect oligomerization and interactions with the microtubule. One of Ipl1's roles might be to fine-tune the coupling of the microtubule interaction with the conformational change required for oligomerization, with phosphorylation resulting in ring breakdown.
名称: Dam1 DeltC mutant complex / タイプ: sample / ID: 1000 詳細: The sample was mainly composed of dimers and little percentage of monomers and trimers. 集合状態: Dimeric decamer / Number unique components: 1
pH: 6.8 詳細: 500 mM NaCl, 20 mM sodium phosphate pH 6.8, 1 mM EDTA
染色
タイプ: NEGATIVE 詳細: The complexes were negatively stained with 2% uranyl formate with the sandwich method between two layers of thin carbon film.
グリッド
詳細: 400 mesh copper grid
凍結
凍結剤: NONE
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電子顕微鏡法
顕微鏡
FEI TECNAI 12
アライメント法
Legacy - 非点収差: objective lens astigmatism was corrected at 120,000 magnification
詳細
The micrographs were taken at low dose mode.
撮影
カテゴリ: FILM / フィルム・検出器のモデル: KODAK SO-163 FILM / デジタル化 - スキャナー: OTHER / デジタル化 - サンプリング間隔: 12.7 µm / 実像数: 200 詳細: The micrographs were scanned on a Nikon Super Coolscan 8000 scanner Od range: 1.4 / ビット/ピクセル: 14