title: Photoactivation of Mutant Isocitrate Dehydrogenase 2 Reveals Rapid Cancer-Associated Metabolic and Epigenetic Changes.
abstract: Isocitrate dehydrogenase is mutated at a key active site arginine residue (Arg172 in IDH2) in many cancers, leading to the synthesis of the oncometabolite (R)-2-hydroxyglutarate (2HG). To investigate the early events following acquisition of this mutation in mammalian cells we created a photoactivatable version of IDH2(R172K), in which K172 is replaced with a photocaged lysine (PCK), via genetic code expansion. Illumination of cells expressing this mutant protein led to a rapid increase in the levels of 2HG, with 2HG levels reaching those measured in patient tumor samples, within 8 h. 2HG accumulation is closely followed by a global decrease in 5-hydroxymethylcytosine (5-hmC) in DNA, demonstrating that perturbations in epigenetic DNA base modifications are an early consequence of mutant IDH2 in cells. Our results provide a paradigm for rapidly and synchronously uncloaking diverse oncogenic mutations in live cells to reveal the sequence of events through which they may ultimately cause transformation.
authors.affiliation: Medical Research Council Laboratory of Molecular Biology , Francis Crick Avenue, Cambridge CB2 0QH, United Kingdom.|Department of Chemistry, University of Cambridge , Lensfield Road, Cambridge CB2 1EW, United Kingdom.
authors.forename: Olivia S
authors.initials: OS
authors.lastname: Walker
authors.affiliation: Medical Research Council Laboratory of Molecular Biology , Francis Crick Avenue, Cambridge CB2 0QH, United Kingdom.|Department of Chemistry, University of Cambridge , Lensfield Road, Cambridge CB2 1EW, United Kingdom.
authors.forename: Simon J
authors.initials: SJ
authors.lastname: Elsässer
authors.affiliation: Medical Research Council Laboratory of Molecular Biology , Francis Crick Avenue, Cambridge CB2 0QH, United Kingdom.
authors.forename: Mohan
authors.initials: M
authors.lastname: Mahesh
authors.affiliation: Department of Chemistry, University of Cambridge , Lensfield Road, Cambridge CB2 1EW, United Kingdom.|Cancer Research U.K. Cambridge Institute , Li Ka Shing Centre, Robinson Way, Cambridge CB2 0RE, United Kingdom.
authors.forename: Martin
authors.initials: M
authors.lastname: Bachman
authors.affiliation: Department of Chemistry, University of Cambridge , Lensfield Road, Cambridge CB2 1EW, United Kingdom.|Cancer Research U.K. Cambridge Institute , Li Ka Shing Centre, Robinson Way, Cambridge CB2 0RE, United Kingdom.
authors.forename: Shankar
authors.initials: S
authors.lastname: Balasubramanian
authors.affiliation: Medical Research Council Laboratory of Molecular Biology , Francis Crick Avenue, Cambridge CB2 0QH, United Kingdom.|Department of Chemistry, University of Cambridge , Lensfield Road, Cambridge CB2 1EW, United Kingdom.
authors.forename: Jason W
authors.initials: JW
authors.lastname: Chin
mesh_terms: D001120:Arginine / Q000378:metabolism; D044127:Epigenesis, Genetic / Q000235:genetics*; D057809:HEK293 Cells; D006801:Humans; D007521:Isocitrate Dehydrogenase / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D008958:Models, Molecular; D015394:Molecular Structure; D050505:Mutant Proteins / Q000235:genetics / Q000378:metabolism*; D009154:Mutation; D009369:Neoplasms / Q000201:enzymology / Q000235:genetics* / Q000378:metabolism*; D055668:Photochemical Processes
chemical_list: D050505:Mutant Proteins; D001120:Arginine; C538784:IDH2 protein, human; D007521:Isocitrate Dehydrogenase