title: Ubiquitin Associates with the N-Terminal Domain of Nerve Growth Factor: The Role of Copper(II) Ions.
abstract: Many biochemical pathways involving nerve growth factor (NGF), a neurotrophin with copper(II) binding abilities, are regulated by the ubiquitin (Ub) proteasome system. However, whether NGF binds Ub and the role played by copper(II) ions in modulating their interactions have not yet been investigated. Herein NMR spectroscopy, circular dichroism, ESI-MS, and titration calorimetry are employed to characterize the interactions of NGF with Ub. NGF1-14, which is a short model peptide encompassing the first 14 N-terminal residues of NGF, binds the copper-binding regions of Ub (KD=8.6 10-5m). Moreover, the peptide undergoes a random coil-polyproline type II helix structural conversion upon binding to Ub. Notably, copper(II) ions inhibit NGF1-14/Ub interactions. Further experiments performed with the full-length NGF confirmed the existence of a copper(II)-dependent association between Ub and NGF and indicated that the N-terminal domain of NGF was a valuable paradigm that recapitulated many traits of the full-length protein.
authors.affiliation: Istituto di Biostrutture e Bioimmagini, Consiglio Nazionale delle Ricerche, Via P. Gaifami18, 95126, Catania, Italy.
authors.forename: Valeria
authors.initials: V
authors.lastname: Lanza
authors.affiliation: Center for Neural Science, New York University, 4 Washington Pl, New York, NY, 10003, USA.
authors.forename: Alessio
authors.initials: A
authors.lastname: Travaglia
authors.affiliation: Dipartimento di Scienze e Tecnologie Ambientali, Biologiche e Farmaceutiche, Seconda Università di Napoli, Via Vivaldi 43, 81100, Caserta, Italy.
authors.forename: Gaetano
authors.initials: G
authors.lastname: Malgieri
authors.affiliation: Dipartimento di Scienze e Tecnologie Ambientali, Biologiche e Farmaceutiche, Seconda Università di Napoli, Via Vivaldi 43, 81100, Caserta, Italy.
authors.forename: Roberto
authors.initials: R
authors.lastname: Fattorusso
authors.affiliation: Dipartimento di Scienze Chimiche, Università degli Studi di Catania, V.le A.Doria 6, 95125, Catania, Italy.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Grasso
authors.affiliation: Istituto di Biostrutture e Bioimmagini, Consiglio Nazionale delle Ricerche, Via P. Gaifami18, 95126, Catania, Italy.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Di Natale
authors.affiliation: Istituto di Biostrutture e Bioimmagini, Consiglio Nazionale delle Ricerche, Via P. Gaifami18, 95126, Catania, Italy.
authors.forename: Valeria
authors.initials: V
authors.lastname: Zito
authors.affiliation: Dipartimento di Scienze Chimiche, Università degli Studi di Catania, V.le A.Doria 6, 95125, Catania, Italy.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Arena
authors.affiliation: Istituto di Biostrutture e Bioimmagini, Consiglio Nazionale delle Ricerche, Via P. Gaifami18, 95126, Catania, Italy.
authors.forename: Danilo
authors.identifier: http://orcid.org/0000-0003-3940-9439
authors.initials: D
authors.lastname: Milardi
authors.affiliation: Istituto di Biostrutture e Bioimmagini, Consiglio Nazionale delle Ricerche, Via P. Gaifami18, 95126, Catania, Italy.|Dipartimento di Scienze Chimiche, Università degli Studi di Catania, V.le A.Doria 6, 95125, Catania, Italy.
authors.forename: Enrico
authors.initials: E
authors.lastname: Rizzarelli
mesh_terms: D002942:Circular Dichroism; D003300:Copper / Q000737:chemistry*; D006801:Humans; D007477:Ions; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D020932:Nerve Growth Factor / Q000737:chemistry*; D010455:Peptides / Q000737:chemistry*; D011485:Protein Binding; D025801:Ubiquitin / Q000737:chemistry*
chemical_list: D007477:Ions; C502240:NGF protein, human; D010455:Peptides; D025801:Ubiquitin; C011083:polyproline; D003300:Copper; D020932:Nerve Growth Factor
keywords: analytical methods; copper; protein-protein interactions; structural biology; structure elucidation