control of parasitophorous vacuole expansion by lystbeige restricts the intracellular growth of leishmania amazonensis控制parasitophorous泡扩张lystbeige限制利什曼虫的细胞内增长amazonensis.pdf

Control of Parasitophorous Vacuole Expansion by LYST/ Beige Restricts the Intracellular Growth of Leishmania amazonensis 1. 1. 2 3 3 2 Jude Wilson , Chau Huynh , Kathleen A. Kennedy , Diane M. Ward , Jerry Kaplan , Alan Aderem , Norma W. Andrews4* 1 Section of Microbial Pathogenesis, Yale University School of Medicine, New Haven, Connecticut, United States of America, 2 Institute for Systems Biology, Seattle, Washington, United States of America, 3 Department of Pathology, University of Utah, Salt Lake City, Utah, United States of America, 4 Department of Cell Biology, Yale University School of Medicine, New Haven, Connecticut, United States of America Abstract The intracellular protozoan Leishmania replicates in parasitophorous vacuoles (PV) that share many features with late endosomes/lysosomes. L. amazonensis PVs expand markedly during infections, but the impact of PV size on parasite intracellular survival is still unknown. Here we show that host cells infected with L. amazonensis upregulate transcription of LYST/Beige, which was previously shown to regulate lysosome size. Mutations in LYST/Beige caused further PV expansion and enhanced L. amazonensis replication. In contrast, LYST/Beige overexpression led to small PVs that did not sustain parasite growth. Treatment of LYST/Beige over-expressing cells with vacuolin-1 reversed this phenotype, expanding PVs and promoting parasite growth. The opposite was seen with E-64d, which reduced PV size in LYST-Beige mutant cells and inhibited L. amazonensis replication. Enlarged PVs appear to protect parasites from oxidative damage, since inhibition of nitric oxide synth