Skeletor, a novel chromosomal protein that redistributes during mitosis provides evidence for the formation of a spindle matrix.
Skeletor, a novel chromosomal protein that redistributes during mitosis provides evidence for the formation of a spindle matrix.
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骨骼是一种新型的染色体蛋白，在有丝分裂过程中重新分布，为纺锤体基质形成提供了证据。
DOI：
10.1083/jcb.151.7.1401
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发表时间：
2000-12-25
影响因子：
7.8
通讯作者：
Johansen, K M
中科院分区：
文献类型：
--
作者：
Walker, D L;Wang, D;Jin, Y;Rath, U;Wang, Y;Johansen, J;Johansen, K M
纺锤体基质被认为有助于在有丝分裂过程中组织和稳定微管纺锤体，尽管证实其存在的分子证据一直难以捉摸。在果蝇中，我们已经克隆和表征了一种新的核蛋白，骨架，我们建议是一个大分子复合物形成这样一个纺锤体矩阵的一部分。Skeletor抗体染色显示，Skeletor在间期与染色体结合，但在前期重新分布成真正的纺锤形纺锤体结构，这先于微管纺锤体形成。在中期，纺锤体，定义由骨架抗体标记，和微管纺锤体coaligned。我们发现，在分裂后期，当染色体分离时，走廊定义的纺锤体保持其纺锤形结构从端到端跨越中期板。因此，通道定义的纺锤体的性质使其成为提供稳定微管和平衡力产生的结构支撑的理想基底。此外，骨架中期纺锤体坚持在微管纺锤体的情况下，强烈暗示的走廊定义的纺锤体的存在并不需要聚合的微管。因此，骨骼肌的鉴定和表征代表了在微管纺锤体形成之前在细胞核内形成的完整纺锤体基质的存在的第一个直接分子证据。
A spindle matrix has been proposed to help organize and stabilize the microtubule spindle during mitosis, though molecular evidence corroborating its existence has been elusive. In Drosophila, we have cloned and characterized a novel nuclear protein, skeletor, that we propose is part of a macromolecular complex forming such a spindle matrix. Skeletor antibody staining shows that skeletor is associated with the chromosomes at interphase, but redistributes into a true fusiform spindle structure at prophase, which precedes microtubule spindle formation. During metaphase, the spindle, defined by skeletor antibody labeling, and the microtubule spindles are coaligned. We find that the skeletor-defined spindle maintains its fusiform spindle structure from end to end across the metaphase plate during anaphase when the chromosomes segregate. Consequently, the properties of the skeletor-defined spindle make it an ideal substrate for providing structural support stabilizing microtubules and counterbalancing force production. Furthermore, skeletor metaphase spindles persist in the absence of microtubule spindles, strongly implying that the existence of the skeletor-defined spindle does not require polymerized microtubules. Thus, the identification and characterization of skeletor represents the first direct molecular evidence for the existence of a complete spindle matrix that forms within the nucleus before microtubule spindle formation.