RNA Editors Sculpt the Transcriptome During Terminal Erythropoiesis

Han, A.; Yermalovich, A.; Najia, M. A. T.; Pearson, D. S.; Fujiwara, Y.; Bolgov, M.; Kubaczka, C.; North, T. E.; Lundin, V.; Orkin, S.; Daley, G. Q.

doi:10.1101/2025.04.03.647020

bioRxiv · 10.1101/2025.04.03.647020

RNA Editors Sculpt the Transcriptome During Terminal Erythropoiesis

Han, A.·Yermalovich, A.·Najia, M. A. T.·Pearson, D. S.·Fujiwara, Y.·Bolgov, M.·Kubaczka, C.·North, T. E.·Lundin, V.·Orkin, S.·Daley, G. Q.

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Abstract

Selective RNA degradation during terminal erythropoiesis results in a globin-rich transcriptome in mature erythrocytes, but the specific RNA decay pathways remain unknown. We found that deficiency of the terminal uridylyl transferase enzyme Zcchc6 and the 3-5 exoribonuclease Dis3l2 in mouse models led to fetal and perinatal reticulocytosis, an accumulation of RNA-rich precursors of terminal erythroid cells, suggesting their crucial roles in terminal red cell differentiation. Notably, knockout embryos exhibited persistent high-level expression of Hbb-bh1 globin, the ortholog of human fetal{gamma} -globin. Perturbation of the Zcchc6-Dis3l2 pathway in mice engineered to express the human {beta}-globin locus likewise increased{gamma} -globin levels in fetal erythroid cells, suggesting that globin switching entails post-transcriptional mechanisms of mRNA destabilization in addition to transcriptional down-regulation. We cultured human hematopoietic stem and progenitor cells (HSPCs), performed CRISPR/Cas9-mediated knockout of ZCCHC6 and DIS3L2, and observed accumulation of RNA and elevated {gamma}-globin levels in terminal erythroid cells. Our findings reveal a conserved role for the ZCCHC6/DIS3L2 RNA editors in terminal erythropoiesis and demonstrate a post-transcriptional mechanism for{gamma} -globin gene switching, advancing research into in vitro erythrocyte generation and{gamma} -globin stabilization to ameliorate hemoglobinopathies.

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Han, A., Yermalovich, A., Najia, M. A. T., Pearson, D. S., Fujiwara, Y., Bolgov, M., Kubaczka, C., North, T. E., Lundin, V., Orkin, S., Daley, G. Q.. 2025-04-05. RNA Editors Sculpt the Transcriptome During Terminal Erythropoiesis. https://doi.org/10.1101/2025.04.03.647020

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