title: Acetylation-defective mutant of Pparγ is associated with decreased lipid synthesis in breast cancer cells.
abstract: In our prior publications we characterized a conserved acetylation motif (K(R)xxKK) of evolutionarily related nuclear receptors. Recent reports showed that peroxisome proliferator activated receptor gamma (PPARγ) deacetylation by SIRT1 is involved in delaying cellular senescence and maintaining the brown remodeling of white adipose tissue. However, it still remains unknown whether lysyl residues 154 and 155 (K154/155) of the conserved acetylation motif (RIHKK) in Pparγ1 are acetylated. Herein, we demonstrate that Pparγ1 is acetylated and regulated by both endogenous TSA-sensitive and NAD-dependent deacetylases. Acetylation of lysine 154 was identified by mass spectrometry (MS) while deacetylation of lysine 155 by SIRT1 was confirmed by in vitro deacetylation assay. An in vivo labeling assay revealed K154/K155 as bona fide acetylation sites. The conserved acetylation sites of Pparγ1 and the catalytic domain of SIRT1 are both required for the interaction between Pparγ1 and SIRT1. Sirt1 and Pparγ1 converge to govern lipid metabolism in vivo. Acetylation-defective mutants of Pparγ1 were associated with reduced lipid synthesis in ErbB2 overexpressing breast cancer cells. Together, these results suggest that the conserved lysyl residues K154/K155 of Pparγ1 are acetylated and play an important role in lipid synthesis in ErbB2-positive breast cancer cells.
authors.affiliation: Department of Cancer Biology, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA, USA.
authors.forename: Lifeng
authors.initials: L
authors.lastname: Tian
authors.affiliation: Department of Cancer Biology, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA, USA.
authors.forename: Chenguang
authors.initials: C
authors.lastname: Wang
authors.affiliation: Department of Biochemistry and Biophysics, University of Rochester, Rochester, NY, USA.
authors.forename: Fred K
authors.initials: FK
authors.lastname: Hagen
authors.affiliation: Department of Cancer Biology, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA, USA.
authors.forename: Michael
authors.initials: M
authors.lastname: Gormley
authors.affiliation: Department of Cancer Biology, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA, USA.
authors.forename: Sankar
authors.initials: S
authors.lastname: Addya
authors.affiliation: Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, Department of Genetics, and The Institute for Diabetes, Obesity, and Metabolism, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA.
authors.forename: Raymond
authors.initials: R
authors.lastname: Soccio
authors.affiliation: Department of Cancer Biology, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA, USA.
authors.forename: Mathew C
authors.initials: MC
authors.lastname: Casimiro
authors.affiliation: Department of Cancer Biology, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA, USA.
authors.forename: Jie
authors.initials: J
authors.lastname: Zhou
authors.affiliation: Department of Cancer Biology, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA, USA.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Powell
authors.affiliation: Department of Pharmacology, Weill Medical College of Cornell University, York Avenue LC216, New York, NY, USA.
authors.forename: Ping
authors.initials: P
authors.lastname: Xu
authors.affiliation: Proteomics Resource Center, Rockefeller University, New York, NY, USA.
authors.forename: Haiteng
authors.initials: H
authors.lastname: Deng
authors.affiliation: Department of Pharmacology, Weill Medical College of Cornell University, York Avenue LC216, New York, NY, USA.
authors.forename: Anthony A
authors.initials: AA
authors.lastname: Sauve
authors.affiliation: Department of Cancer Biology, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA, USA.
authors.forename: Richard G
authors.initials: RG
authors.lastname: Pestell
mesh_terms: D000107:Acetylation; D020816:Amino Acid Motifs / Q000502:physiology; D000818:Animals; D015153:Blotting, Western; D001943:Breast Neoplasms / Q000378:metabolism*; D045744:Cell Line, Tumor; D016922:Cellular Senescence / Q000502:physiology*; D017124:Conserved Sequence; D006801:Humans; D047468:Immunoprecipitation; D050356:Lipid Metabolism / Q000502:physiology*; D013058:Mass Spectrometry; D051379:Mice; D009154:Mutation; D020411:Oligonucleotide Array Sequence Analysis; D047495:PPAR gamma / Q000378:metabolism*; D017434:Protein Structure, Tertiary / Q000502:physiology; D056564:Sirtuin 1 / Q000378:metabolism; D014162:Transfection
chemical_list: D047495:PPAR gamma; C447939:SIRT1 protein, human; D056564:Sirtuin 1