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N⁷-methylguanosine (m⁷G) modification, routinely occurring at mRNA 5′ cap or within tRNAs/rRNAs, also exists internally in messenger RNAs (mRNAs). Although m⁷G-cap is essential for pre-mRNA processing and protein synthesis, the exact role of mRNA internal m⁷G modification remains elusive. Here, we report that mRNA internal m⁷G is selectively recognized by Quaking proteins (QKIs). By transcriptome-wide profiling/mapping of internal m⁷G methylome and QKI-binding sites, we identified more than 1,000 high-confidence m⁷G-modified and QKI-bound mRNA targets with a conserved "GANGAN (N = A/C/U/G)" motif. Strikingly, QKI7 interacts (via C terminus) with the stress granule (SG) core protein G3BP1 and shuttles internal m⁷G-modified transcripts into SGs to regulate mRNA stability and translation under stress conditions. Specifically, QKI7 attenuates the translation efficiency of essential genes in …