Evers Felix, Roverts Rona, Boshoven Cas, Kea-Te Lindert Mariska, Verhoef Julie M J, Sommerdijk Nico, Sinden Robert E, Akiva Anat, Kooij Taco W A
Department of Medical Microbiology, Radboud University Medical Center, Nijmegen, The Netherlands.
Electron Microscopy Center, RTC Microscopy, Radboud University Medical Center, Nijmegen, the Netherlands.
Nat Commun. 2025 Jan 2;16(1):69. doi: 10.1038/s41467-024-55413-5.
Despite the enormous significance of malaria parasites for global health, some basic features of their ultrastructure remain obscure. Here, we apply high-resolution volumetric electron microscopy to examine and compare the ultrastructure of the transmissible male and female sexual blood stages of Plasmodium falciparum as well as the more intensively studied asexual blood stages revisiting previously described phenomena in 3D. In doing so, we challenge the widely accepted notion of a single mitochondrion by demonstrating the presence of multiple mitochondria in gametocytes. We also provide evidence for a gametocyte-specific cytostome, or cell mouth. Furthermore, we generate the first 3D reconstructions of the parasite's endoplasmic reticulum (ER) and Golgi apparatus as well as gametocyte-induced extraparasitic structures in the infected red blood cell. Assessing interconnectivity between organelles, we find frequent structural appositions between the nucleus, mitochondria, and apicoplast. We provide evidence that the ER is a promiscuous interactor with numerous organelles and the trilaminar pellicle of the gametocyte. Public availability of these volumetric electron microscopy resources will facilitate reinterrogation by others with different research questions and expertise. Taken together, we reconstruct the 3D ultrastructure of P. falciparum gametocytes at nanometre scale and shed light on the unique organellar biology of these deadly parasites.
尽管疟原虫对全球健康具有极其重要的意义,但其超微结构的一些基本特征仍不清楚。在这里,我们应用高分辨率体积电子显微镜来检查和比较恶性疟原虫可传播的雄性和雌性有性血液阶段的超微结构,以及之前研究较多的无性血液阶段,以三维方式重现先前描述的现象。在此过程中,我们通过证明配子体中存在多个线粒体,对广为接受的单个线粒体的概念提出了挑战。我们还为配子体特异性的胞口或细胞口提供了证据。此外,我们首次生成了寄生虫内质网(ER)和高尔基体以及配子体诱导的感染红细胞中的细胞外结构的三维重建。通过评估细胞器之间的相互连接性,我们发现细胞核、线粒体和顶质体之间频繁存在结构并置。我们提供的证据表明,内质网与众多细胞器以及配子体的三层pellicle是一种混杂的相互作用者。这些体积电子显微镜资源的公开可用性将便于其他具有不同研究问题和专业知识的人进行重新审视。综上所述,我们在纳米尺度上重建了恶性疟原虫配子体的三维超微结构,并揭示了这些致命寄生虫独特的细胞器生物学特性。