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3646 Requirement for N6-Methyladenosine mRNA Methylation during Human Erythropoiesis

Program: Oral and Poster Abstracts
Session: 101. Red Cells and Erythropoiesis, Excluding Iron: Poster III
Hematology Disease Topics & Pathways:
Research, Fundamental Science, genomics, hematopoiesis, Biological Processes, Technology and Procedures, gene editing
Monday, December 12, 2022, 6:00 PM-8:00 PM

Daniel Kuppers, PhD1*, Yong Peng, PhD2*, Sonali Arora, MS3*, Cindy Wladyka, BS3*, Anne Wilhite3*, Derek Stirewalt3, Beverly Torok-Storb, PhD4*, Andrew Hsieh, MD3*, Chuan He, PhD5,6,7* and Patrick Paddison, PhD8*

1Human Biology Division, Fred Hutchinson Cancer Center, Seattle
2The University of Chicago, Chicago
3Fred Hutchinson Cancer Center, Seattle
4FHCRC D1-100, Seattle, WA
5Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL
6Howard Hughes Medical Institute, University of Chicago, Chicago, IL
7Department of Chemistry and Institute for Biophysical Dynamics, University of Chicago, Chicago, IL
8Human Biology Division, Fred Hutchinson Cancer Center, Seattle, WA

Many of the regulatory features governing erythrocyte specification, maturation, and associated disorders remain enigmatic. To identify new regulators of erythropoiesis, we previously performed a functional genomic screen for genes affecting expression of the erythroid marker CD235a/ GYPA in human erythroid leukemia cells. Among validating hits were genes coding for the N6-methyladenosine (m6A) mRNA methyltransferase (MTase) complex, including, METTL14, METTL3, and WTAP. Here, we show that m6A-MTase activity is required for human erythropoiesis in bone marrow-derived and G-CSF-mobilized CD34+ cells. Ablating m6A-MTase activity by genetic knockout or chemical inhibition blocks early CD71+ erythroid progenitors from transitioning to CD71+CD235A+ stage. Comprehensive mapping of m6A-RNA marks via m6A-SAC-seq revealed more than 30,000 m6A sites among more than 8000 protein coding genes and 100s of non-coding RNAs. A significant portion are dynamic during erythropoiesis and include key regulators of erythropoiesis. Mechanistic studies revealed that many of these events enhanced translation of their targets during erythropoiesis, including PABPC1 and SETD1B. We speculate that added requirement for m6A-MTase activity during erythropoiesis is an adaptation in large mammals to allow the additional expansion of erythroid progenitors.

Disclosures: No relevant conflicts of interest to declare.

*signifies non-member of ASH