A novel SUN1-ALLAN complex coordinates segregation of the bipartite MTOC across the nuclear envelope during rapid closed mitosis in Plasmodium.

Mitosis in eukaryotes involves reorganization of the nuclear envelope (NE) and microtubule-organizing centres (MTOCs). In , the causative agent of malaria, male gametogenesis mitosis is exceptionally rapid and divergent. Within 8 minutes, the haploid male gametocyte genome undergoes three replication cycles (1N to 8N), while maintaining an intact NE.

Whole cell reconstructions of Leishmania mexicana through the cell cycle.

The unicellular parasite Leishmania has a precisely defined cell architecture that is inherited by each subsequent generation, requiring a highly coordinated pattern of duplication and segregation of organelles and cytoskeletal structures. A framework of nuclear division and morphological changes is known from light microscopy, yet this has limited resolution and the intrinsic organisation of organelles within the cell body and their manner of duplication and inheritance is unknown. Using volume electron microscopy approaches, we have produced three-dimensional reconstructions of different promastigote cell cycle stages to give a spatial and quantitative overview of organelle positioning, division and inheritance.

Atypical flagella assembly and haploid genome coiling during male gamete formation in Plasmodium.

Gametogenesis in Plasmodium spp. occurs within the Anopheles mosquito and is essential for sexual reproduction / differentiation and onwards transmission to mammalian hosts. To better understand the 3D organisation of male gametogenesis, we used serial block face scanning electron microscopy (SBF-SEM) and serial-section cellular electron tomography (ssET) of P.