Integrative analysis of nuclear division mechanisms in malaria parasite

恶性疟原虫是最严重的疟疾，每年导致大约50万儿童死亡。发病机制和临床症状与红细胞无性繁殖有关，疟疾感染的严重程度可通过寄生虫载量预测。尽管有丝分裂是这种真核病原体快速增殖的基础，但对核分裂机制的研究却很少，因此提供了一个令人兴奋的研究新途径。与任何模式生物相比，恶性疟原虫有丝分裂显示出显著的形态学差异，表明存在非规范分裂机制。通过结合活细胞成像、超分辨率显微镜和基因组编辑技术的最新进展，我的目标是揭示控制这些机制的分子和细胞事件。有丝分裂是一个高度动态的过程，需要多个结构要素的精确协调。目前还不清楚染色体的复制和分离是如何协调的。此外，已经提出缺乏典型的细胞分裂检查点，并且疟原虫中心体含有功能未知的特定中心体。因此，我建议的三个主要目标是：i)利用活细胞成像分析染色体复制、附着和分离的协调。ii)使用新型DNA活细胞标记和超分辨率显微镜，量化是否明显缺乏有丝分裂检查点导致频繁的分离错误。iii)利用基因组编辑和相关的光学和电子显微镜对中心体的特殊动力学和形态进行功能研究。这些新方法代表了主流疟疾研究的重大偏离，并将大大提高我们对这一主要真核病原体的细胞分裂的理解。新描述的分子标记可能实现高含量筛选，并导致新的疟疾干预策略。

Plasmodium falciparum causes the most severe form of malaria killing about half a million children every year. Pathogenesis and clinical symptoms are linked to asexual proliferation in red blood cells and severity of malaria infection is predicted by parasite load. Even though mitosis is fundamental to the rapid proliferation of this eukaryotic pathogen the mechanisms of nuclear division are poorly studied and thus presents an exciting new avenue for research. P. falciparum mitosis displays significant morphological differences when compared to any model organism suggesting that non-canonical division mechanisms are in place. By combining recent advances in live cell imaging, super-resolution microscopy, and genome-editing technologies I aim to uncover the molecular and cellular events that govern those mechanisms.Mitosis is a highly dynamic process that requires precise coordination of multiple structural elements. Currently, it is unclear how chromosome replication and segregation are coordinated. Further, a lack of canonical cell division checkpoints has been suggested and Plasmodial centrosomes contain specific centrins of unknown function. Hence, the three main objectives of my proposal are: i) Analyze coordination of chromosome replication, attachment and segregation using live cell imaging. ii) Quantify whether apparent lack of mitotic checkpoints causes frequent segregation errors using novel DNA live cell markers and super-resolution microscopy. iii) Functionally investigate the peculiar dynamics, and morphology of centrosomes using genome-editing and correlative light and electron microscopy. These novel approaches represent a significant departure from mainstream malaria research and will drastically improve our understanding of cell division in this major eukaryotic pathogen. Newly described molecular markers may enable high-content screening and lead to new intervention strategies against malaria.