带有旋和孔的快速螺旋:S. pombe核蛋白 nuc2+中的基本重复
T Hirano1, N Kinoshita, K Morikawa
1Department of Biophysics, Faculty of Science, Kyoto University, Japan.
Cell
|January 26, 1990
概括
这种S. pombe nuc2+基因对于细胞分裂期间分离染色体至关重要. 它的新"快速螺旋"结构可能有助于形成染色体支架并结合DNA.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
背景情况:
- 这种S. pombe nuc2+基因在线粒染色体分离中起着至关重要的作用.
- 核2+中的突变导致转相停止,突出显示了它在细胞循环进展中的重要性.
- 核2+蛋白定位在核支架上,这表明它具有结构性的作用.
研究的目的:
- 研究S. pombe nuc2+蛋白质的结构和功能性质.
- 阐明 nuc2+ 蛋白在 DNA 结合和染色体支架中的作用.
- 描述由nuc2+重复部分形成的新型二次结构.
主要方法:
- 在S. pombe. 中分析了nuc2+基因及其蛋白质产物.
- 在体外DNA结合测试中使用富含ATDNA的DNA.
- 循环二重化谱学,有限的蛋白质分解和模型拟合以确定蛋白质结构.
- 调查 ts 突变在重复段中的作用.
主要成果:
- 核2+蛋白具有DNA结合域和十个34氨基酸重复段.
- 一个温度敏感 (ts) 突变被映射到这些重复部分之一.
- 结构分析揭示了由链连接的螺旋段,形成了拟议的"快速螺旋"结构.
- 这种结构具有"旋和孔"的图案,由疏水性相互作用稳定.
结论:
- 核2+蛋白的重复部分形成了一个新的"快速螺旋"二次结构.
- 这种结构可以促进DNA结合和自我关联,形成染色体支架的一部分.
- 了解 nuc2+ 功能为线粒染色体组织和分离提供了洞察力.
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