title: Structure-based derivation of peptide inhibitors to target TGF-β1 receptor for the suppression of hypertrophic scarring fibroblast activation.
abstract: The intermolecular recognition and interaction between human transforming growth factor β-1 (TGF-β1) and its cognate receptor TβRII have been implicated in the pathological condition of hypertrophic scarring (HS). Here, we attempted to rationally derive peptide inhibitors from the complex interface of TGF-β1 with TβRII to disrupt such interaction for the suppression of fibroblast activation involved in HS. A synthetic strategy that integrated computational design and fluorescence-based assay was described to examine the structural basis and energetic property of TGF-β1-TβRII crystal structure, from which a small peptide segment in the complex binding site was stripped artificially. Molecular dynamics simulations revealed that the linear peptide possesses a large intrinsic disorder that would incur considerable entropy penalty upon binding to TβRII; the peptide segment was then extended and cyclized by introducing a disulfide bond across its terminal residues that were premutated to cysteine. Normal mode analysis indicated that, as expected, the peptide flexibility was largely reduced upon the cyclization, and thus, the entropy penalty was minimized substantially, consequently promoting the spontaneous binding of peptide to TβRII. Fluorescence polarization assay confirmed that all linear peptides are typical non-binders of TβRII (Kd= ND), while the designed cyclic peptides exhibit moderate or high affinity with Kdat micromolar level.
authors.affiliation: Department of Plastic Surgery, Shanghai Jiaotong University Affiliated Sixth People's Hospital, Shanghai, China.
authors.forename: Huan
authors.initials: H
authors.lastname: Hu
authors.affiliation: Department of Plastic Surgery, Shanghai Jiaotong University Affiliated Sixth People's Hospital, Shanghai, China.
authors.forename: Songlin
authors.initials: S
authors.lastname: Yang
authors.affiliation: Department of Plastic Surgery, Shanghai Jiaotong University Affiliated Sixth People's Hospital, Shanghai, China.
authors.forename: Jianghong
authors.initials: J
authors.lastname: Zheng
authors.affiliation: Department of Plastic Surgery, Shanghai Jiaotong University Affiliated Sixth People's Hospital, Shanghai, China.
authors.forename: Guangyu
authors.identifier: http://orcid.org/0000-0002-4038-1384
authors.initials: G
authors.lastname: Mao
mesh_terms: D000595:Amino Acid Sequence; D001665:Binding Sites; D002460:Cell Line; D002921:Cicatrix / Q000378:metabolism / Q000473:pathology; D015195:Drug Design; D019277:Entropy; D005347:Fibroblasts / Q000166:cytology / Q000378:metabolism; D005454:Fluorescence Polarization; D006801:Humans; D056004:Molecular Dynamics Simulation; D010455:Peptides / Q000737:chemistry* / Q000378:metabolism; D011485:Protein Binding; D017346:Protein Serine-Threonine Kinases / Q000037:antagonists & inhibitors* / Q000378:metabolism; D020836:Protein Structure, Quaternary; D000077293:Receptor, Transforming Growth Factor-beta Type I; D000077294:Receptor, Transforming Growth Factor-beta Type II; D018125:Receptors, Transforming Growth Factor beta / Q000037:antagonists & inhibitors* / Q000378:metabolism; D015398:Signal Transduction
chemical_list: D010455:Peptides; D018125:Receptors, Transforming Growth Factor beta; D017346:Protein Serine-Threonine Kinases; D000077293:Receptor, Transforming Growth Factor-beta Type I; D000077294:Receptor, Transforming Growth Factor-beta Type II
keywords: hypertrophic scarring; peptide inhibitor; rational molecular design; transforming growth factor β-1 receptor