.(A) Widefield fluorescence microscopy of Dd2 parasites episomally expressing PfHO-GFP. For live imaging, parasites were stained with 25 nM Mitotracker Red and 10 nM Hoechst. For IFA, parasites were fixed and stained with anti-GFP and anti-apicoplast ACP antibodies, as well as DAPI. For all images, the white scale bars indicate 1 µm. The average Pearson correlation coefficient (rp) of red and green channels based on ≥10 images. Pixel intensity plots as a function of distance along the white line in merged images are displayed graphically beside each parasite. (B) Western blot of untreated or Dox/IPP-treated parasites episomally expressing PfHO-GFP and stained with anti-GFP antibody. (C) Live microscopy of PfHO-GFP parasites cultured 7 days in 1 µM doxycycline (Dox) and 200 µM IPP and stained with 25 nM Mitotracker Red and 10 nM Hoechst. (D) Widefield fluorescence microscopy of Dd2 parasites episomally expressing PfHO N-term-GFP and stained as in panel A. (E) Western blot of parasites episomally expressing PfHO N-term-GFP and stained with anti-GFP antibody. (F) Live microscopy of PfHO N-term-GFP parasites cultured 7 d in 1 µM Dox and 200 µM IPP, and stained as in panel C. For each parasite line and condition, ≥20 parasites were analyzed by live imaging and ≥10 parasites were analyzed by IFA. Blackwell AM, Jami-Alahmadi Y, Nasamu AS, Kudo S, Senoo A, Slam C, Tsumoto K, Wohlschlegel JA, Caaveiro JMM, Goldberg DE, Sigala PA. Malaria parasites require a divergent heme oxygenase for apicoplast gene expression and biogenesis.. PMID: 38853871;