Tetrahedral DNA nanostructure-delivered suppressor tRNA ameliorates nephropathy in COL4A5 nonsense mutation-mediated Alport syndrome mice.

Nonsense mutations introduce premature termination codons (PTCs) that trigger mRNA degradation and underlie genetic diseases, including Alport syndrome (AS). Suppressor tRNAs (sup-tRNAs) are potential therapies for such disorders, as they can precisely readthrough PTCs and restore full-length protein synthesis. For AS caused by COL4A5 nonsense-mediated deficiency, we developed a TDN-sup-tRNA delivery strategy using tetrahedral DNA nanostructures (TDNs) characterized by excellent biocompatibility and renal targeting. In a Col4a5-R471X mouse model, TDN-sup-tRNA achieved high readthrough efficiency, restoring COL4A5 protein expression and reconstituting glomerular basement membrane integrity. Notably, proteinuria was reduced to 35% of baseline within 4 weeks. Compared with AAV2/9-mediated delivery, this system exhibited enhanced renal targeting and superior therapeutic efficacy over a one-month treatment period, without detectable toxicity. Collectively, this strategy represents a safe and effective non-viral RNA therapeutic approach for precise correction of nonsense mutation-associated renal diseases.