The N-Glycome regulates the endothelial-to-hematopoietic transition

• DOI: 10.1101/602912
• Publication Date: 2019-04-10T00:06:40Z
• Authors: Dionna M. Kasper; Jared Hintzen; Yinyu Wu; Joey J. Ghersi; Hanna K. Mandl; Kevin E. Salinas; William Armero; Zhiheng He; Ying Sheng; Yixuan Xie; Daniel W. Heindel; Eon Joo Park; William C. Sessa; Lara K. Mahal; Carlito Lebrilla; Karen K. Hirschi; Stefania Nicoli
• Keywords: Glycosylation; beta-Galactoside alpha-2,3-Sialyltransferase; 3-Sialyltransferase; General Science & Technology; Genetically Modified; Regenerative Medicine; Mannosyltransferases; Animals, Genetically Modified; Medicinal and Biomolecular Chemistry; ADAM10 Protein; beta-Galactoside alpha-2; Genes, Reporter; Polysaccharides; Genetics; 2.1 Biological and endogenous factors; Animals; Cell Lineage; Aetiology; Reporter; Glycomics; Zebrafish; Glycoproteins; Endothelial Cells; Hematology; Biological Sciences; Stem Cell Research; Hematopoietic Stem Cells; Sialyltransferases; 3. Good health; MicroRNAs; Genes; Chemical Sciences; Cell Transdifferentiation; Stem Cell Research - Nonembryonic - Non-Human

AbstractHematopoietic stem and progenitor cells (HSPCs) that establish and maintain the blood system in adult vertebrates arise from the transdifferentiation of hemogenic endothelial cells (hemECs) during embryogenesis. This endothelial-to-hematopoietic transition (EHT) is tightly regulated, but the mechanisms are poorly understood. Here, we show that microRNA (miR)-223-mediated regulation of N-glycan biosynthesis in endothelial cells (ECs) regulates EHT. Single cell RNA-sequencing revealed that miR-223 is enriched in hemECs and in oligopotent nascent HSPCs. miR-223 restricts the EHT of lymphoid/myeloid lineages by suppressing the expression of mannosyltransferase alg2 and sialyltransferase st3gal2, two enzymes involved in N-linked protein glycosylation. High-throughput glycomics of ECs lacking miR-223 showed a decrease of high mannose versus sialylated complex/hybrid sugars on N-glycoproteins involved in EHT such as the metalloprotease Adam10. Endothelial-specific expression of an N-glycan Adam10 mutant or of the N-glycoenzymes phenocopied the aberrant HSPC production of miR-223 mutants. Thus, the N-glycome plays a previously unappreciated role as an intrinsic regulator of EHT, with specific mannose and sialic acid modifications serving as key endothelial determinants of their hematopoietic fate.One Sentence SummaryThe N-glycan “sugar code” governs the hematopoietic fate of endothelial cells and regulates blood stem cell production in vivo.