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Delrow, J.

Publications and source records attributed to Delrow, J..

2 recordsLinked to original sources

N6-methyladenosine mRNA marking promotes selective translation of regulons required for human erythropoiesis

Many of the regulatory features governing erythrocyte specification, maturation, and associated disorders remain enigmatic. To identify new regulators of erythropoiesis, we performed a functional genomic screen for genes affecting expression of the erythroid marker CD235a/GYPA. Among validating hits were genes coding for the N6-methyladenosine (m6A) mRNA methyltransferase (MTase) complex, including, METTL14, METTL3, and WTAP. We found that m6A MTase activity promotes erythroid gene expression programs and lineage specification through selective translation of >200 m6A marked mRNAs, including those coding for SETD methyltransferase, ribosome, and polyA RNA binding proteins. Remarkably, loss of m6A marks resulted in dramatic loss of H3K4me3 across key erythroid-specific KLF1 transcriptional targets (e.g., Heme biosynthesis genes). Further, each m6A MTase subunit and a subset of their mRNAs targets, including BRD7, CXXC1, PABPC1, PABPC4, STK40, and TADA2B, were required for erythroid specification. Thus, m6A mRNA marks promote the translation of a network of genes required for human erythropoiesis.

cell biology↗

CRISPR-Cas9 Screens Reveal Genes Regulating a G0-like State in Human Neural Progenitors

Single cell RNA-seq has emerged as a powerful tool for resolving cellular states associated with normal and maligned developmental processes. Here, we used scRNA-seq to examine the cell cycle states of expanding human neural stem cells (hNSCs). From this data, we created a cell cycle classifier, which, in addition to traditional cell cycle phases, also identifies a putative quiescent-like state in neuroepithelial-derived cell types during mammalian neurogenesis and in gliomas. This state, Neural G0, is enriched for expression of quiescent NSC genes and other neurodevelopmental markers found in non-dividing neural progenitors. For gliomas, Neural G0 cell populations and gene expression is significantly associated with less aggressive tumors and extended patient survival. Genetic screens to identify modulators of Neural G0 revealed that knockout of genes associated with the Hippo/Yap and p53 pathways diminished Neural G0 in vitro, resulting in faster G1 transit, down regulation of quiescence-associated markers, and loss of Neural G0 gene expression. Thus, Neural G0 represents a dynamic quiescent-like state found in neuro-epithelial derived cells and gliomas.

cell biology↗