title: Ribose 5-phosphate isomerase inhibits LC3 processing and basal autophagy.
abstract: Autophagy and cellular metabolism are tightly linked processes, but how individual metabolic enzymes regulate the process of autophagy is not well understood. This study implicates ribose-5-phosphate isomerase (RPIA), a key regulator of the pentose phosphate pathway, in the control of autophagy. We used a dual gene deletion strategy, combining shRNA-mediated knockdown studies with CRISPR/Cas9 genome editing. Knockdown of RPIA by shRNA or genomic deletion by CRISPR/Cas9 genome editing, results in an increase of ATG4B-mediated LC3 processing and in the appearance of LC3-positive autophagosomes in cells. Increased LC3 processing upon knockdown of RPIA can be reversed by treatment with the antioxidant N-acetyl cysteine. The results are consistent with a model in which RPIA suppresses autophagy and LC3 processing by modulation of redox signaling.
authors.affiliation: MRC Laboratory for Molecular Cell Biology, University College London, London, UK.
authors.forename: Jacob
authors.initials: J
authors.lastname: Heintze
authors.affiliation: MRC Laboratory for Molecular Cell Biology, University College London, London, UK.
authors.forename: Joana R
authors.initials: JR
authors.lastname: Costa
authors.affiliation: MRC Laboratory for Molecular Cell Biology, University College London, London, UK.
authors.forename: Melanie
authors.initials: M
authors.lastname: Weber
authors.affiliation: MRC Laboratory for Molecular Cell Biology, University College London, London, UK. Electronic address: r.ketteler@ucl.ac.uk.
authors.forename: Robin
authors.initials: R
authors.lastname: Ketteler
mesh_terms: D000111:Acetylcysteine / Q000494:pharmacology; D019747:Aldose-Ketose Isomerases / Q000378:metabolism*; D000818:Animals; D000975:Antioxidants / Q000494:pharmacology; D000071182:Autophagosomes / Q000187:drug effects / Q000378:metabolism; D001343:Autophagy / Q000187:drug effects; D000071183:Autophagy-Related Proteins / Q000378:metabolism; D001483:Base Sequence; D064113:CRISPR-Cas Systems / Q000235:genetics; D003546:Cysteine Endopeptidases / Q000378:metabolism; D055785:Gene Knockdown Techniques; D049452:Green Fluorescent Proteins / Q000378:metabolism; D006367:HeLa Cells; D006801:Humans; D051379:Mice; D008869:Microtubule-Associated Proteins / Q000378:metabolism*; D011499:Protein Processing, Post-Translational / Q000187:drug effects
chemical_list: D000975:Antioxidants; D000071183:Autophagy-Related Proteins; C477012:MAP1LC3A protein, human; D008869:Microtubule-Associated Proteins; D049452:Green Fluorescent Proteins; C507524:ATG4B protein, human; D003546:Cysteine Endopeptidases; D019747:Aldose-Ketose Isomerases; C022548:ribosephosphate isomerase; D000111:Acetylcysteine
keywords: Autophagy; CRISPR; Cas9; Pentose phosphate pathway; RPIA; shRNA