Structural Motility, Institut Curie, CNRS, UMR 144, Paris, France.
Scintillon Institute, San Diego, CA, USA.
Nat Commun. 2021 Mar 25;12(1):1892. doi: 10.1038/s41467-021-22093-4.
Plasmodium falciparum, the causative agent of malaria, moves by an atypical process called gliding motility. Actomyosin interactions are central to gliding motility. However, the details of these interactions remained elusive until now. Here, we report an atomic structure of the divergent Plasmodium falciparum actomyosin system determined by electron cryomicroscopy at the end of the powerstroke (Rigor state). The structure provides insights into the detailed interactions that are required for the parasite to produce the force and motion required for infectivity. Remarkably, the footprint of the myosin motor on filamentous actin is conserved with respect to higher eukaryotes, despite important variability in the Plasmodium falciparum myosin and actin elements that make up the interface. Comparison with other actomyosin complexes reveals a conserved core interface common to all actomyosin complexes, with an ancillary interface involved in defining the spatial positioning of the motor on actin filaments.
疟原虫（Plasmodium falciparum）是疟疾的病原体，它通过一种称为滑行运动的非典型过程移动。肌动球蛋白相互作用是滑行运动的核心。然而，直到现在，这些相互作用的细节仍然难以捉摸。在这里，我们通过电子冷冻显微镜在力冲程结束时（僵硬状态）报告了一个由电子冷冻显微镜确定的不同的恶性疟原虫肌球蛋白系统的原子结构。该结构提供了对寄生虫产生感染性所需的力和运动的详细相互作用的深入了解。值得注意的是，尽管构成界面的恶性疟原虫肌球蛋白和肌动蛋白元件存在重要的可变性，但肌球蛋白在丝状肌动蛋白上的足迹与高等真核生物保守。与其他肌球蛋白复合物的比较揭示了所有肌球蛋白复合物共有的保守核心界面，以及一个辅助界面，用于确定肌球蛋白在肌动蛋白丝上的空间定位。
