Figure 4

Halofuginone short-term induced and long-term selected parasites specifically upregulate intracellular proline concentration. (A,B) Of the 19 proteogenic amino acids assayed from saponin-released purified parasites, only proline concentrations were increased in Dd2 Induced parasites (A) and long-term selected lines HFGRII and HFGRIII (B). The fold increase in amino acid concentration upon induction or selection is expressed as a ratio of induced/selected line measurement over parental Dd2 line measurement. Amino acid levels of saponin-released P. falciparum parasites were quantified from the normalized integrated peak intensity determined by LC-MS. Error bars denote standard deviation.