Poster abstracts

Poster number 51 submitted by Jacob Schwartz

Discriminant silencing of pathogenic AGO1 mutants using cityRNAs

Jacob M. Schwartz (The Ohio State University), Audrey C. Kehling (The Ohio State University), Kotaro Nakanishi (The Ohio State University)

Abstract:
Argonaute syndrome comprises numerous neurodevelopmental disorders involving heterozygous single- to tri-nucleotide mutations in AGO1 and AGO2. Affected individuals present with motor and developmental delays, seizures, craniofacial abnormalities and speech impairment, symptoms often confounded with autism spectrum disorder (1, 2) . Despite disease models revealing mutation-specific phenotypes, treatment applications are poorly documented. Furthermore, conventional siRNAs, which lack precision between point mutations, cannot distinguish between the mutant and wild-type (WT) AGO syndrome mRNAs. Here, we demonstrate that cleavage-inducing tinyRNAs (cityRNAs) (3, 4) discriminate between AGO1 ΔF180 and G199S mutants. Specifically, cityRNAs preferentially silenced reporter genes encoding the recurrent ΔF180 and G199S AGO1 mutants in dual-luciferase assays, while sparing their WT counterpart. At physiologically relevant doses, cityRNAs demonstrated more
selective silencing over siRNA counterparts. These insights highlight cityRNAs as promising candidates for allele-specific therapies for AGO syndrome and other genetic conditions.

References:
1. D. Lessel et al., Germline AGO2 mutations impair RNA interference and human neurological development. Nat Commun 11, 5797 (2020).

2. A. Schalk et al., De novo coding variants in the AGO1 gene cause a neurodevelopmental disorder with intellectual disability. J Med Genet 59, 965-975 (2022).

3. M. S. Park, G. Sim, A. C. Kehling, K. Nakanishi, Human Argonaute2 and Argonaute3 are catalytically activated by different lengths of guide RNA. Proc Natl Acad Sci U S A 117, 28576-28578 (2020).


4. H. Zhang et al., Target cleavage and gene silencing by Argonautes with cityRNAs. Cell Rep 43, 114806 (2024).

Keywords: Argonaute syndrome, RNAi therapeutics