The PF3D7 _0402000 PHIST domain interacts with 4.1R. Cartoon of PF3D7_0402000 showing the predicted transmembrane domain (TMD) or signal anchor, the PHISTa domain, and the C-terminal repeats. The regions of PF3D7_0402000 that were present in the rescued P. falciparum cDNA library plasmids (Library 1 and 2), or subsequently amplified and cloned into the yeast two-hybrid vector pGADT7 are indicated below the cartoon. The ability of each construct to interact with the 4.1R bait was scored at low (LTH: growth on –Leu/-Trp/-His plates) and high stringency (LTHA: growth on –Leu-/Trp/-His/-Ade plates) in strain AH109. Selected positive constructs were quantitatively scored for β-galactosidase activity assays in strain Y187 (assays performed in triplicate; data presented is the average +/− standard deviation between replicates).