Journal: bioRxiv
Article Title: Structural Rewiring of IL-7R Dimerization by an Oncogenic Transmembrane Mutation Can Be Reversed by Rational Design
doi: 10.64898/2026.02.17.706319
Figure Lengend Snippet: (A) Schematic illustration of the TMD design concept for competitive blocking of IL-7R V253G homodimerization and ligand-independent receptor activation but not effecting IL-7 induced signaling. (B) Immunoblot analysis of STAT5 phosphorylation (p-STAT5) in stable BaF3 cells expressing the IL-7R V253G mutant and γc, following lentiviral transduction with WT TM PEP or mutants (V253G, L255Y, V253G/L255Y, V253/S249Y). After 12 h of cytokine deprivation, cells were treated with PBS and collected for immunoblotting. (C) Quantification of p-STAT5 signal in (B) as p-STAT5/STAT5 intensity ratios, normalized to the no-delivery control (None). (D) Immunoblot analysis of p-STAT5 in stable BaF3 cells expressing the IL-7R V253G mutant and γc, following lentiviral transduction with WT TM PEP or mutants as in (B). After 12 h of cytokine deprivation, cells were treated with 50 ng/mL IL-7 for 2 h and collected for immunoblotting. (E) Quantification of p-STAT5 signal in (D) as p-STAT5/STAT5 intensity ratios, normalized to the no-delivery control (None). (F) Schematic illustration of the mRNA–LNP delivery system. The mRNA encoding designed TM PEP was delivered into BaF3 cells using lipid nanoparticles (LNPs) comprising ionizable lipids (SM-102) and auxiliary components ( Top ). The mRNAs were modified with N1-methylpseudouridine (m1Ψ) and contained a 5′ Cap1/ARCA and 3′ poly(A) tail (∼100A) ( Middle ). The designed TM PEP sequences were listed with mutated residues in red ( Bottom ). (G) Immunoblot analysis of p-STAT5 in stable BaF3 cells expressing the IL-7R V253G mutant and γc, following mRNA – LNP delivery of WT TM PEP or mutants (V253G, L255Y, V253G/L255Y, V253/S249Y). After 12 h of cytokine deprivation, cells were treated with PBS and collected for immunoblotting. (H) Quantification of p-STAT5 signal in (G) as p-STAT5/STAT5 intensity ratios, normalized to the no-delivery control (None). (I) Immunoblot analysis of p-STAT5 in stable BaF3 cells expressing the IL-7R V253G mutant and γc, following mRNA – LNP delivery of WT TM PEP or mutants as in (G). After 12 h of cytokine deprivation, cells were treated with 50 ng/mL IL-7 for 2 h and collected for immunoblotting. (J) Quantification of p-STAT5 signal in (I) as p-STAT5/STAT5 intensity ratios, normalized to the no-delivery control (None). Unpaired student’s t test was used and data were shown as mean ± SEM calculated from three independent experiments. Represents statistically significant, n.s. (not significant); * p ≤ 0.05, ** p ≤ 0.01, *** p ≤ 0.001, **** p ≤ 0.0001. PBS, phosphate-buffered saline. s.e.=short exposure. l.e.= long exposure.
Article Snippet: Phospho-STAT5 rabbit mAb (#9359), phospho-Jak1 rabbit mAb (#74129), STAT5 rabbit mAb (#94205), Jak1 rabbit mAb (#3344), and phospho-STAT5 rabbit mAb AF647 (#9365) were purchased from Cell Signaling Technology. β-Actin rabbit mAb (#AC026) and goat anti-rabbit IgG H+L (HRP) (#AS014) were purchased from ABclonal.
Techniques: Blocking Assay, Activation Assay, Western Blot, Phospho-proteomics, Expressing, Mutagenesis, Transduction, Control, Modification, Saline