Identification of vulnerable antimalarial targets using conditional loss of function mutants.

To counter the threat of drug-resistant malaria parasites, drug discovery efforts should be focused on compounds with novel modes of action. Furthermore, drug candidates acting on vulnerable targets should be triaged as they are most likely to be fast-acting antimalarials and have a lower propensity to resistance. Vulnerable targets can be identified by phenotypic assessment of conditional loss of function mutants. Here, we edited 16 Plasmodium falciparum genes to epitope-tag the target protein and control target expression with the glmS ribozyme tool. Target localization was assessed by confocal microscopy. Conditional knockdown to generate loss of function mutants was assessed by transcriptomic RNA sequencing and western blotting. Target vulnerability assay of the mutants identified UGT1, DHFS-FPGS, and GAT as new vulnerable targets.