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bioRxiv · 10.1101/2023.12.19.572439

Modulation of prion protein expression through cryptic splice site manipulation

Gentile, J. E.·Corridon, T. L.·Mortberg, M. A.·D'Souza, E. N.·Whiffin, N.·Minikel, E. V.·Vallabh, S. M.
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Abstract

Lowering expression of prion protein (PrP) is a well-validated therapeutic strategy in prion disease, but additional modalities are urgently needed. In other diseases, small molecules have proven capable of modulating pre-mRNA splicing, sometimes by forcing inclusion of cryptic exons that reduce gene expression. Here, we characterize a cryptic exon located in human PRNPs sole intron and evaluate its potential to reduce PrP expression through incorporation into the 5 untranslated region (5UTR). This exon is homologous to exon 2 in non-primate species, but contains a start codon that would yield an upstream open reading frame (uORF) with a stop codon prior to a splice site if included in PRNP mRNA, potentially downregulating PrP expression through translational repression or nonsense-mediated decay. We establish a minigene transfection system and test a panel of splice site alterations, identifying mutants that reduce PrP expression by as much as 78%. Our findings nominate a new therapeutic target for lowering PrP.

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Gentile, J. E., Corridon, T. L., Mortberg, M. A., D'Souza, E. N., Whiffin, N., Minikel, E. V., Vallabh, S. M.. 2023-12-19. Modulation of prion protein expression through cryptic splice site manipulation. https://doi.org/10.1101/2023.12.19.572439

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