title: Copper binds the carboxy-terminus of trefoil protein 1 (TFF1), favoring its homodimerization and motogenic activity.
abstract: Trefoil protein 1 (TFF1) is a small secreted protein belonging to the trefoil factor family of proteins, that are present mainly in the gastrointestinal (GI) tract and play pivotal roles as motogenic factors in epithelial restitution, cell motility, and other incompletely characterized biological processes. We previously reported the up-regulation of TFF1 gene in copper deficient rats and the unexpected property of the peptide to selectively bind copper. Following the previous evidence, here we report the characterization of the copper binding site by fluorescence quenching spectroscopy and mass spectrometric analyses. We demonstrate that Cys58 and at least three Glu surrounding residues surrounding it, are essential to efficiently bind copper. Moreover, copper binding promotes the TFF1 homodimerization, thus increasing its motogenic activity in in vitro wound healing assays. Copper levels could then modulate the TFF1 functions in the GI tract, as well as its postulated role in cancer progression and invasion.
authors.affiliation: Division of Biomedicine Arturo Leone, Department of Pharmaceutical Sciences, University of Salerno, Via Ponte don Melillo, 84084, Fisciano (SA), Italy.
authors.forename: Alessandra
authors.initials: A
authors.lastname: Tosco
authors.forename: Maria Chiara
authors.initials: MC
authors.lastname: Monti
authors.forename: Bianca
authors.initials: B
authors.lastname: Fontanella
authors.forename: Sandro
authors.initials: S
authors.lastname: Montefusco
authors.forename: Luca
authors.initials: L
authors.lastname: D'Andrea
authors.forename: Barbara
authors.initials: B
authors.lastname: Ziaco
authors.forename: Daniela
authors.initials: D
authors.lastname: Baldantoni
authors.forename: Marie-Christine
authors.initials: MC
authors.lastname: Rio
authors.forename: Liberato
authors.initials: L
authors.lastname: Marzullo
mesh_terms: D000595:Amino Acid Sequence; D019943:Amino Acid Substitution; D000818:Animals; D001665:Binding Sites / Q000235:genetics; D002460:Cell Line; D002465:Cell Movement; D003300:Copper / Q000378:metabolism*; D006801:Humans; D007700:Kinetics; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D010446:Peptide Fragments / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D055503:Protein Multimerization; D051381:Rats; D013050:Spectrometry, Fluorescence; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D000071163:Trefoil Factor-1; D025521:Tumor Suppressor Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D014945:Wound Healing
chemical_list: D010446:Peptide Fragments; C051838:TFF1 protein, human; D000071163:Trefoil Factor-1; D025521:Tumor Suppressor Proteins; D003300:Copper