pfeIK1- parasites do not phosphorylate eIF2α in amino acid-limiting conditions. pfeik1- clones C1 and E6, as well as the 3D7 parent clone and a pfeik2- clone used as controls, were synchronized to the late ring stage and equally partitioned into individual cultures. Growth of the parasites was continued up to 5 hours at 37°C in either complete RPMI (CM) or in RPMI lacking amino acids (-AA). CM was added back to one amino acid-deprived culture, and re-incubated for an additional 45 minutes. Total lysates from the parasites were prepared for SDS-PAGE, followed by immunoblotting with antibodies against phosphorylated eIF2α (anti-phosho eIF2α). Antibodies against the endoplasmic reticulum marker BiP (anti-BiP) served as the loading control.