Introduction and Objective: Type I (IFNα) and Type II (IFNγ) interferons have been shown to play a critical role in T1D pathogenesis. Studies on pancreatic biopsies from individuals with recent-onset T1D suggest an upregulation of IFN-stimulated gene signatures. However, their impact on the β-cell epitranscriptome and translatome remains untested.Methods: Human islets from 12 cadaveric donors and EndoC-βH1 cells were treated with IFNα or IFNγ for 8 or 24 h to simulate early T1D conditions. Polyribosomal profiling (PRP) and Ribo-seq were performed to assess changes in RNA translation. Long-read native RNA-seq was performed to characterize time- and cytokine-specific remodeling in RNA modifications. RIP-LCMV-GP mice were utilized for in vivo experiments.Results: PRP analysis showed that IFNs strongly inhibit mRNA elongation, whereas immunoblotting revealed a temporally coordinated activation of the integrated stress response (ISR). Ribo-seq demonstrated that IFNs enhance translation of noncanonical ORFs linked to several T1D-associated risk variants. Long-read RNA-seq uncovered cytokine- and time-dependent remodeling of RNA modifications. Following IFNγ treatment, we observed a significant increase in de novo (1,400), m5C (25,131), and pSU (6,100) modifications at 8 h, which were markedly reduced by 24 h (m6A: 104; m5C: 3,252; pSU: 1,273). IFNα produced a similar pattern, with high numbers of newly modified sites at 8 h that decreased by 24 h. Several stress-responsive genes (e.g., CXCL10, IRF9) exhibited exclusive pSU modification, suggesting transcript stabilization. Pathway analysis of modified genes highlighted antigen processing, nucleotide metabolism, toll-like receptor signaling, and related immune pathways. In vivo, ISR inhibition reduced T1D incidence by 70% in RIP-LCMV-GP mice and restored mRNA translation in islets.Conclusion: Inflammation-induced ISR activation drives RNA modification dynamics and translation defects in β-cells, suggesting that ISR targeting may be a potential therapeutic strategy for T1D.
J. Rana: None. S. Bhattacharya: None. T. Hato: None. C. Evans-Molina: Advisory Panel; Ended; Sanofi. Speaker’s Bureau; Ended; Sanofi. Other – Shared grant and project; Current; Neurodon. Advisory Panel; Current; Diogenyx. F. Syed: None.
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