MagIC-Cryo-EM:在磁珠上进行稀缺宏分子在异质样本中的结构确定
Yasuhiro Arimura1,2, Hide A Konishi1, Hironori Funabiki1
1Laboratory of Chromosome and Cell Biology, The Rockefeller University, New York, NY 10065.
bioRxiv : the preprint server for biology
|February 8, 2024
概括
磁隔离和度 (MagIC) -冷-EM 通过显著降低度要求,使稀缺宏分子的结构分析成为可能. 这种新方法提供了对细胞循环调节的质子结构的洞察.
科学领域:
- 结构生物学 结构生物学
- 生物化学 生化学
- 分子生物学分子生物学
背景情况:
- 低温电子显微镜 (cryo-EM) 单颗粒分析需要高度的大分子 (0.055.0 mg/ml).
- 对于稀缺或异质的生物目标来说,达到这些度往往是具有挑战性的.
研究的目的:
- 开发一种新的冷EM技术,以分析超低度的大分子.
- 为了研究细胞周期期间链接组素H1.8-关联核细胞的结构变化.
主要方法:
- 磁隔离和度 (MagIC) -冷EM:一种使用磁珠捕获和度目标的方法.
- 将MagIC-cryo-EM调整为染色体免疫沉 (ChIP),以隔离特定的染色体复合物.
- 重复选择以排除垃圾 (DuSTER) 颗粒固以提高冷EM数据质量.
主要成果:
- 磁IC-cryo-EM可将所需的目标度降低到<0.0005 mg/ml.
- 从互相和转相染色体中对H1.8-关联核细胞体的结构变异进行了表征.
- 与H1.8共同分离的核胺NPM2的3D冷EM结构揭示了不同的开放和闭合形状.
结论:
- 在复杂样品中,MagIC-cryo-EM对于稀缺的大分子结构分析是有效的.
- 这项研究提供了对H1.8与核细胞相结合的细胞周期依赖调节的结构性见解.
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