Figure 5. Non-essential roles and regulation of gene expression of CoA biosynthesis genes of PanK1 and PanK2 during P. yoelii blood stage development.

(A) Average blood stage parasitemia (% infected erythrocytes out of >5000 cells counted) in groups of four BALB/c mice per strain following IV injection of 5000 infected erythrocytes confirms that deletion of PyPanK1 or PyPanK2 does not lead to any significant reduction in blood stage parasitemia compared to WT and WT-like Pyp230p(−) parasites only at day 10 pi. However, the deletion of PyPanK1 slightly, but significantly, affected blood stage parasitemia at days 2, 4, 6 and 8 pi. (B) Deletion of PyPanK2 results in upregulation of PyPanK1 and other CoA biosynthesis genes transcripts, while deletion of PyPanK1 results in a slight downregulation of CoA biosynthesis genes transcripts. Transcript levels of PyPanK1 and PyPanK2 as well as other genes involved in CoA biosynthesis (PAT, PPCS, PPCDC, PPAT and DPCK) in wild-type, Pypank1(−) or Pypank2(−) strains were estimated by real time-PCR from total RNA isolated from similar amounts of infected mouse blood with 1% parasitemia. Relative gene expression levels were normalized to 18S ribosomal RNA expression in P. yoelii blood stages, and are presented as the mean of two independent experiments, error bars represent standard deviation.