Human WIPI-1 puncta-formation: a novel assay to assess mammalian autophagy

FEBS Lett. 2007 Jul 24;581(18):3396-404. doi: 10.1016/j.febslet.2007.06.040. Epub 2007 Jun 27.

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.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Autophagy* / drug effects
  • Autophagy-Related Proteins
  • Carrier Proteins / chemistry
  • Carrier Proteins / genetics
  • Carrier Proteins / metabolism*
  • Cell Line, Tumor
  • Cell Membrane / metabolism
  • Genes, Reporter / genetics
  • Humans
  • Membrane Proteins
  • Microscopy, Electron, Transmission
  • Microscopy, Immunoelectron
  • Molecular Sequence Data
  • Mutation / genetics
  • Phosphatidylinositol 3-Kinases / metabolism
  • Protein Binding
  • Sirolimus / pharmacology

Substances

  • Autophagy-Related Proteins
  • Carrier Proteins
  • Membrane Proteins
  • WIPI-1 protein, human
  • Phosphatidylinositol 3-Kinases
  • Sirolimus