title: Peptidyl-prolyl cis/trans-isomerase A1 (Pin1) is a target for modification by lipid electrophiles.
abstract: Oxidation of membrane phospholipids is associated with inflammation, neurodegenerative disease, and cancer. Oxyradical damage to phospholipids results in the production of reactive aldehydes that adduct proteins and modulate their function. 4-Hydroxynonenal (HNE), a common product of oxidative damage to lipids, adducts proteins at exposed Cys, His, or Lys residues. Here, we demonstrate that peptidyl-prolyl cis/trans-isomerase A1 (Pin1), an enzyme that catalyzes the conversion of the peptide bond of pSer/pThr-Pro moieties in signaling proteins from cis to trans, is highly susceptible to HNE modification. Incubation of purified Pin1 with HNE followed by MALDI-TOF/TOF mass spectrometry resulted in detection of Michael adducts at the active site residues His-157 and Cys-113. Time and concentration dependencies indicate that Cys-113 is the primary site of HNE modification. Pin1 was adducted in MDA-MB-231 breast cancer cells treated with 8-alkynyl-HNE as judged by click chemistry conjugation with biotin followed by streptavidin-based pulldown and Western blotting with anti-Pin1 antibody. Furthermore, orbitrap MS data support the adduction of Cys-113 in the Pin1 active site upon HNE treatment of MDA-MB-231 cells. siRNA knockdown of Pin1 in MDA-MB-231 cells partially protected the cells from HNE-induced toxicity. Recent studies indicate that Pin1 is an important molecular target for the chemopreventive effects of green tea polyphenols. The present study establishes that it is also a target for electrophilic modification by products of lipid peroxidation.
authors.affiliation: Department of Biochemistry, Vanderbilt Institute of Chemical Biology, Center in Molecular Toxicology, Vanderbilt University School of Medicine, Nashville, TN 37232-0146, USA.
authors.forename: Christopher D
authors.initials: CD
authors.lastname: Aluise
authors.forename: Kristie
authors.initials: K
authors.lastname: Rose
authors.forename: Mariana
authors.initials: M
authors.lastname: Boiani
authors.forename: Michelle L
authors.initials: ML
authors.lastname: Reyzer
authors.forename: Joseph D
authors.initials: JD
authors.lastname: Manna
authors.forename: Keri
authors.initials: K
authors.lastname: Tallman
authors.forename: Ned A
authors.initials: NA
authors.lastname: Porter
authors.forename: Lawrence J
authors.initials: LJ
authors.lastname: Marnett
mesh_terms: D000447:Aldehydes / Q000378:metabolism*; D001943:Breast Neoplasms / Q000201:enzymology / Q000235:genetics / Q000378:metabolism*; D020134:Catalytic Domain; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D057930:Click Chemistry; D005260:Female; D055785:Gene Knockdown Techniques; D006801:Humans; D015227:Lipid Peroxidation; D000072340:NIMA-Interacting Peptidylprolyl Isomerase; D019696:Peptidylprolyl Isomerase / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D034741:RNA, Small Interfering / Q000235:genetics
chemical_list: D000447:Aldehydes; D000072340:NIMA-Interacting Peptidylprolyl Isomerase; D034741:RNA, Small Interfering; C000606846:PIN1 protein, human; D019696:Peptidylprolyl Isomerase; C027576:4-hydroxy-2-nonenal