title: Molecular characterization of LC3-associated phagocytosis reveals distinct roles for Rubicon, NOX2 and autophagy proteins.
abstract: LC3-associated phagocytosis (LAP) is a process wherein elements of autophagy conjugate LC3 to phagosomal membranes. We characterize the molecular requirements for LAP, and identify Rubicon as being required for LAP but not autophagy. Rubicon is recruited to LAPosomes and is required for the activity of a Class III PI(3)K complex containing UVRAG but lacking ATG14 and Ambra1. This allows for the sustained localization of PtdIns(3)P, which is critical for recruitment of downstream autophagic proteins and stabilization of the NOX2 complex to produce reactive oxygen species. Both PtdIns(3)P and reactive oxygen species are required for conjugation of LC3 to LAPosomes and subsequent association with LAMP1(+) lysosomes. LAP is induced by engulfment of Aspergillus fumigatus, a fungal pathogen that commonly afflicts immunocompromised hosts, and is required for its optimal clearance in vivo. Therefore, we have identified molecules that distinguish LAP from canonical autophagy, thereby elucidating the importance of LAP in response to A. fumigatus infection.
authors.affiliation: Department of Immunology, St Jude Children's Research Hospital, Memphis, Tennessee 38105, USA.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Martinez
authors.affiliation: Department of Immunology, St Jude Children's Research Hospital, Memphis, Tennessee 38105, USA.
authors.forename: R K Subbarao
authors.initials: RK
authors.lastname: Malireddi
authors.affiliation: Department of Pathology and Immunology, Washington University School of Medicine, St Louis, Missouri 63110, USA.
authors.forename: Qun
authors.initials: Q
authors.lastname: Lu
authors.affiliation: Department of Immunology, St Jude Children's Research Hospital, Memphis, Tennessee 38105, USA.
authors.forename: Larissa Dias
authors.initials: LD
authors.lastname: Cunha
authors.affiliation: 1] Department of Immunology, St Jude Children's Research Hospital, Memphis, Tennessee 38105, USA [2] Embryonic Stem Cell Laboratory, St Jude Children's Research Hospital, Memphis, Tennessee 38105, USA.
authors.forename: Stephane
authors.initials: S
authors.lastname: Pelletier
authors.affiliation: 1] Department of Immunology, St Jude Children's Research Hospital, Memphis, Tennessee 38105, USA [2] Embryonic Stem Cell Laboratory, St Jude Children's Research Hospital, Memphis, Tennessee 38105, USA.
authors.forename: Sebastien
authors.initials: S
authors.lastname: Gingras
authors.affiliation: Department of Pathology and Immunology, Washington University School of Medicine, St Louis, Missouri 63110, USA.
authors.forename: Robert
authors.initials: R
authors.lastname: Orchard
authors.affiliation: Department of Cancer Biology, University of Cincinnati College of Medicine, Cincinnati, Ohio 45267, USA.
authors.forename: Jun-Lin
authors.initials: JL
authors.lastname: Guan
authors.affiliation: St Jude Proteomics Facility, St Jude Children's Research Hospital, Memphis, Tennessee 38105, USA.
authors.forename: Haiyan
authors.initials: H
authors.lastname: Tan
authors.affiliation: 1] St Jude Proteomics Facility, St Jude Children's Research Hospital, Memphis, Tennessee 38105, USA [2] Departments of Structural Biology and Developmental Neurobiology, St Jude Children's Research Hospital, Memphis, Tennessee 38105, USA.
authors.forename: Junmin
authors.initials: J
authors.lastname: Peng
authors.affiliation: Department of Immunology, St Jude Children's Research Hospital, Memphis, Tennessee 38105, USA.
authors.forename: Thirumala-Devi
authors.initials: TD
authors.lastname: Kanneganti
authors.affiliation: Department of Pathology and Immunology, Washington University School of Medicine, St Louis, Missouri 63110, USA.
authors.forename: Herbert W
authors.initials: HW
authors.lastname: Virgin
authors.affiliation: Department of Immunology, St Jude Children's Research Hospital, Memphis, Tennessee 38105, USA.
authors.forename: Douglas R
authors.initials: DR
authors.lastname: Green
mesh_terms: D000818:Animals; D001232:Aspergillus fumigatus / Q000502:physiology; D001343:Autophagy; D000071183:Autophagy-Related Proteins; D002460:Cell Line; D058546:Class III Phosphatidylinositol 3-Kinases / Q000378:metabolism; D005260:Female; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D054884:Host-Pathogen Interactions; D015151:Immunoblotting; D047908:Intracellular Signaling Peptides and Proteins / Q000235:genetics / Q000378:metabolism*; D008264:Macrophages / Q000378:metabolism / Q000382:microbiology; D008297:Male; D008562:Membrane Glycoproteins / Q000235:genetics / Q000378:metabolism*; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D008822:Mice, Transgenic; D018613:Microscopy, Confocal; D008869:Microtubule-Associated Proteins / Q000235:genetics / Q000378:metabolism*; D000074662:NADPH Oxidase 2; D019255:NADPH Oxidases / Q000235:genetics / Q000378:metabolism*; D010587:Phagocytosis; D010588:Phagosomes / Q000378:metabolism / Q000382:microbiology; D018129:Phosphatidylinositol Phosphates / Q000378:metabolism; D034622:RNA Interference; D017382:Reactive Oxygen Species / Q000378:metabolism; D025521:Tumor Suppressor Proteins / Q000235:genetics / Q000378:metabolism; D033921:Vesicular Transport Proteins / Q000235:genetics / Q000378:metabolism
chemical_list: C561107:Atg14 protein, mouse; D000071183:Autophagy-Related Proteins; D047908:Intracellular Signaling Peptides and Proteins; C480860:Map1lc3b protein, mouse; D008562:Membrane Glycoproteins; D008869:Microtubule-Associated Proteins; D018129:Phosphatidylinositol Phosphates; D017382:Reactive Oxygen Species; C000601571:Rubcn protein, mouse; D025521:Tumor Suppressor Proteins; C512859:UVRAG protein, mouse; D033921:Vesicular Transport Proteins; D049452:Green Fluorescent Proteins; C488842:Cybb protein, mouse; D000074662:NADPH Oxidase 2; D019255:NADPH Oxidases; D058546:Class III Phosphatidylinositol 3-Kinases