title: The C-terminal domain of the transcriptional corepressor CtBP is intrinsically unstructured.
abstract: C-terminal binding proteins (CtBPs) are moonlighting proteins involved in nuclear transcriptional corepression and in Golgi membrane tubule fission. Structural information on CtBPs is available for their substrate-binding domain, responsible for transcriptional repressor recognition/binding, and for the nucleotide-binding domain, involved in NAD(H)-binding and dimerization. On the contrary, little is known about the structure of CtBP C-terminal region ( approximately 90 residues), hosting sites for post-translational modifications. In the present communication we apply a combined approach based on bioinformatics, nuclear magnetic resonance, circular dichroism spectroscopy, and small-angle X-ray scattering, and we show that the CtBP C-terminal region is intrinsically unstructured in the full-length CtBP and in constructs lacking the substrate- and/or the nucleotide-binding domains. The flexible nature of this protein region, and its structural transitions, may be instrumental for CtBP recognition and binding to diverse molecular partners.
authors.affiliation: Department of Biomolecular Sciences and Biotechnology, and CNR-INFM, University of Milano, I-20131 Milano, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Nardini
authors.forename: Dmitri
authors.initials: D
authors.lastname: Svergun
authors.forename: Peter V
authors.initials: PV
authors.lastname: Konarev
authors.forename: Stefania
authors.initials: S
authors.lastname: Spanò
authors.forename: Mauro
authors.initials: M
authors.lastname: Fasano
authors.forename: Chiara
authors.initials: C
authors.lastname: Bracco
authors.forename: Alessandra
authors.initials: A
authors.lastname: Pesce
authors.forename: Alessandra
authors.initials: A
authors.lastname: Donadini
authors.forename: Claudia
authors.initials: C
authors.lastname: Cericola
authors.forename: Francesco
authors.initials: F
authors.lastname: Secundo
authors.forename: Alberto
authors.initials: A
authors.lastname: Luini
authors.forename: Daniela
authors.initials: D
authors.lastname: Corda
authors.forename: Martino
authors.initials: M
authors.lastname: Bolognesi
mesh_terms: D000429:Alcohol Oxidoreductases; D000595:Amino Acid Sequence; D001665:Binding Sites; D002942:Circular Dichroism; D004268:DNA-Binding Proteins; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D008969:Molecular Sequence Data; D010750:Phosphoproteins; D017510:Protein Folding; D012097:Repressor Proteins / Q000737:chemistry*; D014157:Transcription Factors / Q000737:chemistry*; D014158:Transcription, Genetic
chemical_list: D004268:DNA-Binding Proteins; D010750:Phosphoproteins; D012097:Repressor Proteins; D014157:Transcription Factors; D000429:Alcohol Oxidoreductases; C096794:C-terminal binding protein