The function of the bacterial Clp complex in the apicoplast of malaria parasites

Malaria is a lethal human disease caused by intracellular parasites of the genus Plasmodium. This disease affects millions of people worldwide, and is often associated with severe cardiac complications. The deadliest species, P. falciparum, is a minute eukaryotic cell that is remarkably complex and contains a unique algal endosymbiont known as the apicoplast. The apicoplast harbors essential metabolic pathways and it is considered an ideal parasite-specific drug target, but little is known about its biogenesis. Parasites homologs of the Clp family of proteins, that act as key regulators in bacterial cells, localize to the apicoplast but their function in parasite biology is unidentified. In bacteria, a ClpC chaperone interacts with a ClpP protease and together with a ClpR, a non-catalytic subunit, they form a proteolytic complex that degrades proteins in a regulated manner. Preliminary data show that one apicoplast localized Clp chaperone, PfClpC, is essential for apicoplast integrity and parasite growth. Based on the preliminary data, It is hypothesized that the apicoplast Clp proteins form a regulated proteolytic complex that governs apicoplast biogenesis.

To meet the goals, Anat Florentin will take a genetic approach combined with cell biology and biochemical assays. Anat Florentin will study the activity of the PfClpCP/R complex in vivo, growing malaria parasites in a tissue culture of human Red Blood Cells. She has adapted and further developed conditional knockdown techniques, and has been using the CRISPR/Cas9 technology for rapid and efficient genome engineering. The main objectives to be achieved are mutant and transgenic cell lines where genes from the Clp complex are tagged and conditionally inhibited. These parasites lines will be subjected to various assays to monitor parasites viability and apicoplast function. These will be combined with a novel genetic reporter that I designed specifically to monitor apicoplast protein degradation. Achieving these goals will lead to the identification of new drug targets and to the repurpose of antibacterials as antimalarials. These will contribute to the global fight against malaria and will support the worldwide progress towards healthier lives with reduced mortality and morbidity, including all cardiovascular complications

Basic Science

Jul 2018 — Jun 2020

$114,368

United States