Directed Blocking of TGF-? Receptor I Binding Site Using Tailored Peptide Segments to Inhibit its Signaling Pathway.

ABSTRACT: Background:TGF-? isoforms play crucial roles in diverse cellular processes. Therefore, targeting and inhibiting TGF-? signaling pathway provides a potential therapeutic opportunity. TGF-? isoforms bind and bring the receptors (T?RII and T?RI) together to form a signaling complex in an ordered manner. Objectives:Herein, an antagonistic variant of TGF-? (AnT?) has been designed and prepared to inhibit the formation of signaling complex and consequently its signaling pathway. This TGF-? homodimeric variant contains intact T?RII binding sites and blocked T?RI binding sites by substituting three peptide segments. So, AnT? could only bind to T?RII, but prevent binding and recruitment of T?RI to form a signaling complex. Materials and Methods:A reliable model of AnT? was built and re?ned using molecular dynamics (MD) simulation, followed by investigating the interactions of AnT? with the receptors using in silico docking studies. After expression of disulfide-linked AnT? in a SHuffle strain and purification of the protein using affinity chromatography, its biological activity was evaluated using Mink lung epithelial cells (Mvl Lu). Results:No meaningful significant changes in AnT? structure were observed when compared with the native protein. Based on the docking analysis, AnT? binds to T?RII similar to TGF-? and its binding to T?RI was diminished considerably which was consistent with our design purpose. Cell-based bioassay indicated that AnT? could modulate TGF-?-induced cell growth inhibition. Conclusions:Our analysis suggests that the antagonistic potency of AnT? can be used as an anti-TGF? signaling factor in the future perspectives.

SUBMITTER: Sepehri S 

PROVIDER: S-EPMC7461711 | biostudies-literature | 2020 Jan

REPOSITORIES: biostudies-literature