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Updated: Jul 13, 2026

In Vitro and In Vivo Detection of Mitophagy in Human Cells, C. Elegans, and Mice
Published on: November 22, 2017
Human WIPI-1 puncta-formation: a novel assay to assess mammalian autophagy
Tassula Proikas-Cezanne1, Sabine Ruckerbauer, York-Dieter Stierhof
1Autophagy Laboratory, Department of Molecular Biology, University of Tuebingen, Auf der Morgenstelle 15, 72076 Tuebingen, Germany. tassula.proikas-cezanne@uni-tuebingen.de
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.

