A genome-wide CRISPR screen in lipid-rich versus lipid-poor culture conditions, published in Nature Communications, identified the dense granule protein GRA38 as a regulator of parasite fitness that depends on lipid availability.
GRA38 has phosphatidic acid phosphatase activity that depends on a conserved DxDxT/V catalytic motif. Parasites lacking GRA38 accumulate phosphatidic acid, show broad changes in lipid composition, and are less virulent in mice.
Read the paper: A genome-wide CRISPR screen identifies GRA38 as a key regulator of lipid homeostasis during Toxoplasma gondii adaptation to lipid-rich conditions. Nat Commun 2025.