来自人类疟疾寄生虫Plasmodium falciparum核酸家政蛋白HAM1的结构功能分析
Debanjan Saha1, Atanu Pramanik2, Aline Freville3
1Division of Infectious Diseases and Immunology, CSIR-Indian Institute of Chemical Biology, Kolkata, India.
The FEBS journal
|July 14, 2024
概括
疟疾寄生虫Plasmodium falciparum中的一种酶PfHAM1,可以去除有害的非正规核酸. 它的结构和功能得到了阐明,揭示了它在维护基因组完整性的作用.
科学领域:
- 结构生物学 结构生物学
- 寄生虫学的寄生虫学
- 生物化学 生物化学
背景情况:
- 非正规核酸由于变种效应,威胁到Plasmodium falciparum基因组完整性.
- 虽然PfHAM1 (氨酸/氨酸三酸铁酸酶) 维持了核酸平衡,但其结构-功能关系尚不清楚.
研究的目的:
- 为了阐明Plasmodium falciparum中PfHAM1的结构和功能.
- 了解PfHAM1在核酸平衡和基因组完整性中的作用.
主要方法:
- 射线晶体学和尺寸排除色谱学-用于结构分析的多角度光散射.
- 异热定位热度计,以评估核酸结合亲和力.
- 通过CRISPR-Cas9/DiCre介导的基因编辑和活细胞成像来研究PfHAM1的活体功能.
主要成果:
- PfHAM1形成了一个同质体结构,确定了关键基质和金属结合残留物.
- 与人类氨酸三酸铁酸酶相比,观察到β-片主框架的结构差异.
- PfHAM1表现出依赖Mg++的活性和对dITP的高度亲和力.
- 在细胞质中,PfHAM1无处不在,其表达在热粒体和分裂体中更高.
- 在标准条件下,pfHAM1-null寄生虫存活下来,这表明它在核酸清除中起着辅助作用.
结论:
- 这项研究提供了关于PfHAM1的第一个全面的结构和功能见解,Plasmodium falciparum中的非典型核酸清洁酶.
- 通过在红细胞内阶段清除非正规核酸,PfHAM1在维持基因组完整性方面发挥着作用.
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