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Bridgwater, R.

Publications and source records attributed to Bridgwater, R..

2 recordsLinked to original sources

The translatome of quiescent Plasmodium falciparum gametocytes reveals parasite pyridoxal 5'-phosphate (PLP) biosynthesis is essential for efficient mosquito stage development

The ability of Plasmodium falciparum gametocytes to remain quiescent within the vertebrate host but poised for rapid onward development in the mosquito is an adaptation essential to maximise the onward spread of malaria. In this dormant state, mature infectious stage V gametocytes are largely unaffected by most antimalarial drugs and our limited understanding of how gametocytes prepare for mosquito transmission has hindered the identification of new molecular targets for transmission-blocking therapeutics. In this study, we move beyond the total proteome of gametocytes and define the translatome of mature stage V gametocytes using L-azidohomoalanine incorporation into nascent proteins, click chemistry purification and proteomic analysis. We identify the proteins and pathways that gametocytes sustain in preparation for transmission during this dormant period and through genetic disruption, we validate this approach by demonstrating the importance of parasite pyridoxal 5-phosphate biosynthesis for mosquito transmission.

microbiology↗

Targeting Aurora kinases as essential cell cycle regulators to deliver multi-stage antimalarials against Plasmodium falciparum

Kinases that play critical roles in the development and adaptation of Plasmodium falciparum present novel opportunities for chemotherapeutic intervention. Of particular interest are mitotic kinases that regulate the proliferation of the parasites by controlling nuclear division, segregation and cytokinesis. We evaluated the potential of human Aurora kinase (Aur) inhibitors to inhibit P. falciparum development by targeting members of the Aurora-related kinase (Ark) family in this parasite. Several human AurB inhibitors exhibited multistage potency (<250 nM) against all proliferative stages of parasite development, including asexual blood stages, liver schizonts and male gametes. Among the most potent compounds, hesperadin and AT83 exhibit >1000x selectivity towards the parasite without concerns about mammalian cell toxicity. Importantly, we identified PfArk1 as the principal vulnerable Ark family member, with specific inhibition of PfArk1 as the primary target for hesperadin and the human anaplastic lymphoma kinase (ALK) inhibitor TAE684. Hesperadins whole-cell and protein activity validates it as a unique PfArk1 tool compound. Inhibition of PfArk1 results in the parasites inability to complete mitotic processes, presenting with unsegregated, multi-lobed nuclei caused by aberrant microtubule organization. This suggests that PfArk1 is the main Aur mitotic kinase in proliferative stages of Plasmodium, characterized by bifunctional AurA and B activity. This paves the way for drug discovery campaigns based on hesperadin targeting PfArk1.

molecular biology↗