Plasmodium falciparum coronin organizes arrays of parallel actin filaments potentially guiding directional motility in invasive malaria parasites

作者：Maya A. Olshina, Fiona Angrisano, Danushka S. Marapana, David T. Riglar, Kartik Bane, Wilson Wong, Bruno Catimel, Meng-Xin Yin, Andrew B. Holmes, Friedrich Frischknecht, David R. Kovar, Jake Baum · 发表于：Malaria Journal · 年份：2015 · DOI：10.1186/s12936-015-0801-5 · 被引用次数：60 · 研究领域：Malaria Research and Control、Cellular Mechanics and Interactions、Cardiomyopathy and Myosin Studies

BACKGROUND: Gliding motility in Plasmodium parasites, the aetiological agents of malaria disease, is mediated by an actomyosin motor anchored in the outer pellicle of the motile cell. Effective motility is dependent on a parasite myosin motor and turnover of dynamic parasite actin filaments. To date, however, the basis for directional motility is not known. Whilst myosin is very likely orientated as a result of its anchorage within the parasite, how actin filaments are orientated to facilitate directional force generation remains unexplained. In addition, recent evidence has questioned the linkage between actin filaments and secreted surface antigens leaving the way by which motor force is transmitted to the extracellular milieu unknown. Malaria parasites possess a markedly reduced repertoire of actin regulators, among which few are predicted to interact with filamentous (F)-actin directly. One of these, PF3D7_1251200, shows strong homology to the coronin family of actin-filament binding proteins, herein referred to as PfCoronin. METHODS: Here the N terminal beta propeller domain of PfCoronin (PfCor-N) was expressed to assess its ability to bind and bundle pre-formed actin filaments by sedimentation assay, total internal reflection fluorescence (TIRF) microscopy and confocal imaging as well as to explore its ability to bind phospholipids. In parallel a tagged PfCoronin line in Plasmodium falciparum was generated to determine the cellular localization of the protein during ase...