Lysosomal Aspartylglucosaminidase Couples Glycoprotein Catabolism to Cell-Surface GlycoRNA Production

Cao, W.; Yang, Z.; Zhang, C.; Yi, L.; Miao, Y.; Zhao, S.; Yu, C.; Zhou, X.; Li, T.; Zhou, Y.; Lu, T.; Zhang, Y.; Dou, Y.; Fujita, M.; Xie, Y.; Liu, Y.-S.; Xie, R.

doi:10.64898/2026.01.13.699189

bioRxiv · 10.64898/2026.01.13.699189

Lysosomal Aspartylglucosaminidase Couples Glycoprotein Catabolism to Cell-Surface GlycoRNA Production

Cao, W.·Yang, Z.·Zhang, C.·Yi, L.·Miao, Y.·Zhao, S.·Yu, C.·Zhou, X.·Li, T.·Zhou, Y.·Lu, T.·Zhang, Y.·Dou, Y.·Fujita, M.·Xie, Y.·Liu, Y.-S.·Xie, R.

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Abstract

GlycoRNAs, small non-coding RNAs covalently linked to N-glycans, reveal an unexpected intersection between RNA biology and glycosylation, with potential roles in immunity and cell-cell communication. The origins and biogenesis of their glycans remain unclear. Using CRISPR-Cas9 screening, metabolic glycan labeling and lysosome-targeted proteomics, we reconfirm canonical N-glycosylation enzymes (STT3A/B) and identify components of the mannose-6-phosphate (M6P) lysosomal sorting pathway (GNPTAB, M6PR) as essential contributors. Strikingly, lysosomal aspartylglucosaminidase (AGA) acts as a rate-limiting regulator, linking glycoprotein catabolism to glycoRNA formation. Loss of AGA collapses both abundance and diversity of RNA-linked N-glycans, while pulse-chase tracing shows glycoprotein-derived glycans are repurposed for RNA glycosylation. These findings position lysosomes as active participants in RNA modification and redefine glycoRNA biogenesis as a metabolically integrated process.

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Cao, W., Yang, Z., Zhang, C., Yi, L., Miao, Y., Zhao, S., Yu, C., Zhou, X., Li, T., Zhou, Y., Lu, T., Zhang, Y., Dou, Y., Fujita, M., Xie, Y., Liu, Y.-S., Xie, R.. 2026-01-13. Lysosomal Aspartylglucosaminidase Couples Glycoprotein Catabolism to Cell-Surface GlycoRNA Production. https://doi.org/10.64898/2026.01.13.699189

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