Primary structure of NuMA, an intranuclear protein that defines a novel pathway for segregation of proteins at mitosis.
Primary structure of NuMA, an intranuclear protein that defines a novel pathway for segregation of proteins at mitosis.
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DOI：
10.1083/jcb.116.6.1395
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发表时间：
1992-03
期刊：
影响因子：
--
通讯作者：
Cleveland DW
中科院分区：
文献类型：
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作者：
Compton DA;Szilak I;Cleveland DW
从特异性结合人类细胞有丝分裂装置各个部分的单克隆抗体集合中（1991. J. Cell Biol. 112：1083-1097），其中两种（1F1和1H1）识别大于200-kD的核内蛋白，该蛋白在核膜破裂后立即与纺锤体结合，并沿着纺锤体微管向下前进，最终集中在中心体周围区域。在后期完成时，该蛋白质从纺锤体微管解离，并通过核孔输入再生核中。跨越相应 7.2-kb mRNA 整个长度的重叠 cDNA 克隆揭示了编码的 236,278 D 多肽，预计该多肽包含两个由不连续 α 螺旋分隔的球状结构域，具有采用卷曲螺旋结构的特征。相应的基因高度保守，但 DNA 序列和预测的氨基酸序列均未显示出与之前报道的任何显着同源性。由于 cDNA 还编码对先前描述的两种蛋白质（NuMA 和嗜中性蛋白）特异的抗体识别的表位，并且所有三种蛋白质在细胞周期中都显示出相似的分子量和定位，因此 NuMA、嗜中性蛋白和 1F1/1H1 抗原代表相同的蛋白质或蛋白质家族，其原始名称 NuMA 似乎最合适。虽然 NuMA 的功能仍不确定，但其在有丝分裂时不寻常的分离模式定义了细胞分裂过程中核蛋白分离的新途径。
From a collection of monoclonal antibodies that specifically bind to various parts of the mitotic apparatus in human cells (1991. J. Cell Biol. 112: 1083-1097), two (1F1 and 1H1) recognize a greater than 200- kD intranuclear protein that associates with the spindle immediately upon nuclear envelope breakdown and progresses down the spindle microtubules to concentrate ultimately at the pericentrosomal region. At the completion of anaphase this protein dissociates from the spindle microtubules and is imported into the regenerating nuclei through the nuclear pores. Overlapping cDNA clones that span the entire length of the corresponding 7.2-kb mRNA reveal an encoded polypeptide of 236,278 D that is predicted to contain two globular domains separated by a discontinuous alpha-helix with characteristics for adopting a coiled- coil structure. The corresponding gene is highly conserved but neither the DNA sequence nor the predicted amino acid sequence shows significant homology to any previously reported. Since the cDNA also encodes the epitopes recognized by antibodies specific for two previously described proteins, NuMA and centrophilin, and all three show similar molecular weights and localization during the cell cycle, NuMA, centrophilin, and the 1F1/1H1 antigen represent either the same protein or a family of proteins, for which the original name, NuMA, seems most appropriate. While the function of NuMA remains uncertain, its unusual pattern of segregation at mitosis defines a novel pathway for the segregation of nuclear proteins during cell division.