The Plasmodium lipocalin PV5 is trafficked to the parasite digestive compartments. (C) Dual protein localization of PV5 to extensions of the PV and to intraparasitic structures in P. berghei. Transgenic parasites expressing the PV marker GFPPV and the endogenous PbPV5 gene fused to mCherry-3xMyc were imaged live. Shown are the mCherry (red, first row) and GFP channels (green, second row), a merge of both signals (third row) and a merge of differential interference contrast images (DIC), and Hoechst 33342 nuclear stain (blue, fourth row). Cyan arrowheads, PbPV5 in PV tubules. Numbers represent normalized mCherry intensity values obtained by quantitative live fluorescence microscopy. n = 44 parasites. (E) PV5 localizes to the central FV, intraparasitic vesicles and to the PV in P. falciparum. Transgenic parasites expressing the endogenous PfPV5 gene fused to mCherry were imaged live in the presence of Lysosensor blue DND-167 (LS Blue). Shown are the signals of mCherry (red, first column), LS Blue (green, second column), a merge of both signals (third column), and DIC images (fourth column). Cyan arrowhead, PfPV5 in PV (Upper). Yellow arrowhead, PfPV5 in small intraparasitic vesicles (Lower). (Scale bars, 5 µm.). Matz JM, Drepper B, Blum TB, van Genderen E, Burrell A, Martin P, Stach T, Collinson LM, Abrahams JP, Matuschewski K, Blackman MJ. A lipocalin mediates unidirectional heme biomineralization in malaria parasites. Proc Natl Acad Sci U S A. 2020 14;117(28):16546-16556. PMID: 32601225;