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oai:figshare.com:article/34017848 2026-09-28T17:54:56Z category_1 category_4 category_915 category_7 category_8 category_12 category_13 category_132 portal_5 item_type_1 month_year_09_2026

PfATG18 marks the DVM without junctional enrichment. Yasmin Schmitz (11974910) Moumita Sengupta (25132859) Carola Schneider (3743791) Tanja Ziesmann (3318936) Franziska Hellmold (25132862) Ute Distler (115774) Rudolph Reimer (190562) Joachim Michael Matz (25132865) Biophysics Biochemistry Physical Sciences not elsewhere classified Medicine Microbiology Cell Biology Genetics Infectious Diseases related protein 18 div >< p broad architectural destabilization balance cargo influx associated protein machinery antimalarial drugs unchanged 3d electron microscopy membrane sector phenocopied endocytic membrane homeostasis endocytic membrane dynamics vacuole constantly fuses specialized digestive vacuole stage parasites hypersensitive vacuolar membrane dynamics efficient hemoglobin processing degrading hemoglobin within asexual parasite proliferation plasmodium falciparum </ atpase assembly factor atg18 links v vacuolar membrane vacuole ’ malaria parasites atpase assembly parasite ’ parasite survival parasite death incoming hemoglobin pf </ vesicle trafficking rendered ring regulatory influence quantitative live proton pump point mutation multifaceted role key regulator interactions indicates interact directly findings establish filled vesicles direct interference decrease sensitivity (A) Structural organization of PfATG18. Alignment of the ScATG18 crystal structure (PDB: 6KYB; [<a href="http://www.plospathogens.org/article/info:doi/10.1371/journal.ppat.1014608#ppat.1014608.ref034" target="_blank">34</a>]) with the PfATG18 AlphaFold 3 model reveals a conserved seven-bladed β-propeller core. Loops were omitted due to absence in the crystal structure or low-confidence predictions. RMSD = 1.18 Å. Key structural features are highlighted in the schematics and legend. (B) Genetic strategy for tagging and conditional deletion of PfATG18. Cas9-mediated cleavage and homologous recombination yield atg18-mNG:loxP parasites expressing loxP-flanked recodonized (rec.) PfATG18 fused to mNG. RAP-inducible DiCre excises the loxP-flanked sequence. Shown are the endogenous wild-type locus, the repair template, and the modified locus before and after excision. Arrowheads and dotted lines denote the positions of the primers and the expected PCR products, with amplicon sizes indicated. A second independent line (atg18:loxP) lacks the mNG tag. (C) PfATG18 is expressed throughout the entire asexual intraerythrocytic cycle. Representative parasite stages are shown. DNA: Hoechst 33342. (D) PfATG18 localizes around hemozoin, visualized using two crossed polarizers. (E) PfATG18-mNG staining delineates the DV, as demonstrated by co-localization with PM2-mCh. (F,G) PfATG18 colocalizes with CRT at the DVM (F) and is occasionally observed at DV-adjacent compartments (G, arrowhead). (H-J) PfATG18 is not enriched at DV-lobe junctions. (H) Normalized CRT-mCh and PfATG18-mNG intensities were subtracted to reveal signals exclusive to each protein. The arrowhead marks the membrane junction. Maximum ATG18-mNG intensities at DV, lobe, and junction (I) showed no junctional accumulation beyond the sum of both membranes (J). Individual and mean values; one-way ANOVA with Tukey’s test; n = 30 parasites, 3 experiments. n.s., p > 0.05; ***, p < 0.001. (K-O) PfATG18 shows no overlap with fluorescently tagged early (K) or late (L) endosomal markers, retromer components (M,N) or apicoplast-resident folate transporter 2 (FT2, O) [<a href="http://www.plospathogens.org/article/info:doi/10.1371/journal.ppat.1014608#ppat.1014608.ref045" target="_blank">45</a>]. Scale bars: 5 µm. Source data are provided as a <a href="http://www.plospathogens.org/article/info:doi/10.1371/journal.ppat.1014608#ppat.1014608.s015" target="_blank">S3 File</a>. 2026-09-28T18:08:16Z Image Figure 10.1371/journal.ppat.1014608.g001 https://figshare.com/articles/figure/_p_i_Pf_i_ATG18_marks_the_DVM_without_junctional_enrichment_p_/34017848 CC BY 4.0