Programmed ribosomal frameshifting during PLEKHM2 mRNA decoding generates a constitutively active proteoform that supports myocardial function

Summary

Programmed ribosomal frameshifting is a process where a proportion of ribosomes change their reading frame on an mRNA. While frameshifting is commonly used by viruses, very few phylogenetically conserved examples are known in nuclear encoded genes. Here, we report a +1 frameshifting event during decoding of the human gene PLEKHM2 that provides access to a second internally overlapping ORF. The new carboxyl-terminal domain of this frameshift protein forms an α helix, which relieves PLEKHM2 from autoinhibition and allows it to move to the tips of cells without activation by ARL8. Reintroducing both the canonically translated and frameshifted protein are necessary to restore normal contractile function of PLEKHM2 knockout cardiomyocytes, demonstrating the necessity of frameshifting for normal cardiac activity.

Authors Loughran G, De Pace R, Ding N, Zhang J, Jungreis I, Carancini G, Mudge JM, Wang J, Kellis M, Atkins JF, Baranov PV, Firth AE, Li X, Bonifacino JS, Khan YA
Journal Science advances
Publication Date 2025 Oct 24;11(43):eady1742
PubMed 41134891
PubMed Central PMC12551717
DOI 10.1126/sciadv.ady1742

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