title: Human WIPI-1 puncta-formation: a novel assay to assess mammalian autophagy.
abstract: Autophagy depends on the activity of phosphoinositide-3 kinase class III to generate PI(3)P. We identified the human WIPI protein family of PI(3)P-binding factors and showed that WIPI-1 (Atg18) is linked to autophagy in human cells. Induction of autophagy by rapamycin, gleevec, thapsigargin and amino acid deprivation led to an accumulation of WIPI-1 at LC3-positive membrane structures (WIPI-1 puncta-formation), suggested to represent autophagosomal isolation membranes. WIPI-1 puncta-formation is inhibited by wortmannin and LY294002, and PI(3)P-binding-deficient WIPI-1 is puncta-formation-incompetent. Quantification of WIPI-1 puncta should be suitable to assay mammalian autophagy.
authors.affiliation: Autophagy Laboratory, Department of Molecular Biology, University of Tuebingen, Auf der Morgenstelle 15, 72076 Tuebingen, Germany. tassula.proikas-cezanne@uni-tuebingen.de
authors.forename: Tassula
authors.initials: T
authors.lastname: Proikas-Cezanne
authors.forename: Sabine
authors.initials: S
authors.lastname: Ruckerbauer
authors.forename: York-Dieter
authors.initials: YD
authors.lastname: Stierhof
authors.forename: Carolin
authors.initials: C
authors.lastname: Berg
authors.forename: Alfred
authors.initials: A
authors.lastname: Nordheim
mesh_terms: D000595:Amino Acid Sequence; D001343:Autophagy / Q000187:drug effects; D000071183:Autophagy-Related Proteins; D002352:Carrier Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D045744:Cell Line, Tumor; D002462:Cell Membrane / Q000378:metabolism; D017930:Genes, Reporter / Q000235:genetics; D006801:Humans; D008565:Membrane Proteins; D046529:Microscopy, Electron, Transmission; D016253:Microscopy, Immunoelectron; D008969:Molecular Sequence Data; D009154:Mutation / Q000235:genetics; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D011485:Protein Binding; D020123:Sirolimus / Q000494:pharmacology
chemical_list: D000071183:Autophagy-Related Proteins; D002352:Carrier Proteins; D008565:Membrane Proteins; D019869:Phosphatidylinositol 3-Kinases; D020123:Sirolimus; C522812:WIPI1 protein, human