Dynamic Acetylation of Phosphoenolpyruvate Carboxykinase Toggles Enzyme Activity between Gluconeogenic and Anaplerotic Reactions.

1. Mol Cell. 2018 Sep 6;71(5):718-732.e9. doi: 10.1016/j.molcel.2018.07.031. Dynamic Acetylation of Phosphoenolpyruvate Carboxykinase Toggles Enzyme Activity between Gluconeogenic and Anaplerotic Reactions. Latorre-Muro P(1), Baeza J(2), Armstrong EA(2), Hurtado-Guerrero R(3), Corzana F(4), Wu LE(5), Sinclair DA(6), López-Buesa P(1), Carrodeguas JA(7), Denu JM(8). Author information: (1)Departamento de Producción Animal y Ciencia de los Alimentos, Facultad de Veterinaria, Universidad de Zaragoza, 50013 Zaragoza, Spain; Instituto de Biocomputación y Física de Sistemas Complejos (BIFI), BIFIIQFR (CSIC) Joint Unit, Universidad de Zaragoza, 50018 Zaragoza, Spain. (2)Wisconsin Institute for Discovery and Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health-Madison, Madison, WI 53715, USA. (3)Instituto de Biocomputación y Física de Sistemas Complejos (BIFI), BIFIIQFR (CSIC) Joint Unit, Universidad de Zaragoza, 50018 Zaragoza, Spain; Fundación ARAID, Government of Aragón, Zaragoza, Spain. (4)Departamento de Química, Centro de Investigación en Síntesis Química, Universidad de La Rioja, 26006 Logroño, Spain. (5)Department of Pharmacology, School of Medical Sciences, The University of New South Wales, Sydney, NSW 2052, Australia. (6)Department of Pharmacology, School of Medical Sciences, The University of New South Wales, Sydney, NSW 2052, Australia; Department of Genetics, Paul F. Glenn Laboratories for the Biological Mechanisms of Aging, Harvard Medical School, Boston, MA 02115, USA. (7)Instituto de Biocomputación y Física de Sistemas Complejos (BIFI), BIFIIQFR (CSIC) Joint Unit, Universidad de Zaragoza, 50018 Zaragoza, Spain; Departamento de Bioquímica y Biología Molecular y Celular, Facultad de Ciencias, Universidad de Zaragoza, 50009 Zaragoza, Spain; IIS Aragón, Zaragoza, Spain. Electronic address: carrode@unizar.es. (8)Wisconsin Institute for Discovery and Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health-Madison, Madison, WI 53715, USA; Morgridge Institute for Research, Madison, WI 53715, USA. Electronic address: john.denu@wisc.edu. Cytosolic phosphoenolpyruvate carboxykinase (PCK1) is considered a gluconeogenic enzyme; however, its metabolic functions and regulatory mechanisms beyond gluconeogenesis are poorly understood. Here, we describe that dynamic acetylation of PCK1 interconverts the enzyme between gluconeogenic and anaplerotic activities. Under high glucose, p300-dependent hyperacetylation of PCK1 did not lead to protein degradation but instead increased the ability of PCK1 to perform the anaplerotic reaction, converting phosphoenolpyruvate to oxaloacetate. Lys91 acetylation destabilizes the active site of PCK1 and favors the reverse reaction. At low energy input, we demonstrate that SIRT1 deacetylates PCK1 and fully restores the gluconeogenic ability of PCK1. Additionally, we found that GSK3β-mediated phosphorylation of PCK1 decreases acetylation and increases ubiquitination. Biochemical evidence suggests that serine phosphorylation adjacent to Lys91 stimulates SIRT1-dependent deacetylation of PCK1. This work reveals an unexpected capacity of hyperacetylated PCK1 to promote anaplerotic activity, and the intersection of post-translational control of PCK1 involving acetylation, phosphorylation, and ubiquitination. Copyright © 2018 Elsevier Inc. All rights reserved. DOI: 10.1016/j.molcel.2018.07.031 PMCID: PMC6188669 PMID: 30193097 [Indexed for MEDLINE] Conflict of interest statement: Declaration of Interests The authors declare no competing interests.