Centrosomes Isolated from Spisula solidissima Oocytes Contain Rings and an Unusual Stoichiometric Ratio of α/β Tubulin
Centrosomes Isolated from Spisula solidissima Oocytes Contain Rings and an Unusual Stoichiometric Ratio of α/β Tubulin
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从 Spisula Solidissima 卵母细胞中分离的中心体含有环和不寻常的化学计量比的 α/β 微管蛋白
作者：
J. Vogel;T. Stearns;C. Rieder;R. Palazzo
中心体依赖的微管成核涉及微管蛋白亚基与着丝点周围物质的相互作用。为了研究中心体依赖的微管成核的生化和结构基础，从孤雌生殖激活的Spisula solidissima卵母细胞中分离了能够将微管组织成星形阵列的中心体。中压电子显微镜断层扫描显示，每个中心体由一个中心粒组成，中心粒周围环绕着环状结构，直径∼为25 nm，长度为25 nm。与中心体结合的蛋白质包括：(A)含有M期特异性磷酸表位的蛋白质(mpm-2)，(B)α-，β-和γ-微管蛋白，(C)肌动蛋白，和(D)三种20kD的低分子量蛋白质。γ-微管蛋白不是一种MPM-2磷酸蛋白，而是中心体中含量最丰富的微管蛋白。相对较少的α-或β-微管蛋白与中心体相互作用，中心体中α-和β-微管蛋白的比例并不是预期的1：1，而是1：4.6，这表明中心体中含有β-微管蛋白，而不是与α-微管蛋白二聚体。
Centrosome-dependent microtubule nucleation involves the interaction of tubulin subunits with pericentriolar material. To study the biochemical and structural basis of centrosome-dependent microtubule nucleation, centrosomes capable of organizing microtubules into astral arrays were isolated from parthenogenetically activated Spisula solidissima oocytes. Intermediate voltage electron microscopy tomography revealed that each centrosome was composed of a single centriole surrounded by pericentriolar material that was studded with ring-shaped structures ∼25 nm in diameter and <25 nm in length. A number of proteins copurified with centrosomes including: (a) proteins that contained M-phase–specific phosphoepitopes (MPM-2), (b) α-, β-, and γ-tubulins, (c) actin, and (d) three low molecular weight proteins of <20 kD. γ-Tubulin was not an MPM-2 phosphoprotein and was the most abundant form of tubulin in centrosomes. Relatively little α- or β-tubulin copurified with centrosomes, and the ratio of α- to β-tubulin in centrosomes was not 1:1 as expected, but rather 1:4.6, suggesting that centrosomes contain β-tubulin that is not dimerized with α-tubulin.
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缓冲条件和非微管蛋白因素严重影响海胆卵微管蛋白的微管动态不稳定性。
影响因子：
--
作者：
Simon,JR;Parsons,SF;Salmon,ED
通讯作者：
Salmon,ED
哺乳动物中心体和盘基网柄核相关体的单克隆抗体揭示了微管组织中心成分的异质性。
影响因子：
--
作者：
Sellitto,C;Kimble,M;Kuriyama,R
通讯作者：
Kuriyama,R
DOI：
10.1073/pnas.80.10.2926
发表时间：
1983-01-01
期刊：
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA-BIOLOGICAL SCIENCES
影响因子：
--
作者：
DAVIS, FM;TSAO, TY;RAO, PN
通讯作者：
RAO, PN
影响因子：
2.2
作者：
PENCZEK, P;MARKO, M;FRANK, J
通讯作者：
FRANK, J
磷蛋白是有丝分裂微管组织中心的组成部分。
DOI：
10.1073/pnas.81.14.4439
发表时间：
1984
影响因子：
11.1
作者：
Vandre,DD;Davis,FM;Rao,PN;Borisy,GG
通讯作者：
Borisy,GG