Hydroxymethylation at Gene Regulatory Regions Directs Stem/Early Progenitor Cell Commitment during Erythropoiesis
journal contributionposted on 12.04.2016, 00:00 by Jozef Madzo, Hui Liu, Alexis Rodriguez, Aparna Vasanthakumar, Sriram Sundaravel, Donne Bennett D Caces, Timothy J Looney, Li Zhang, Janet B Lepore, Trisha Macrae, Robert Duszynski, Alan H Shih, Chun-Xiao Song, Miao Yu, Yiting Yu, Robert Grossman, Brigitte Raumann, Amit Verma, Chuan He, Ross L Levine, Don Lavelle, Bruce T Lahn, Amittha Wickrema, Lucy A Godley
Hematopoietic stem cell differentiation involves the silencing of self-renewal genes and induction of a specific transcriptional program. Identification of multiple covalent cytosine modifications raises the question of how these derivatized bases influence stem cell commitment. Using a replicative primary human hematopoietic stem/progenitor cell differentiation system, we demonstrate dynamic changes of 5-hydroxymethylcytosine (5-hmC) during stem cell commitment and differentiation to the erythroid lineage. Genomic loci that maintain or gain 5-hmC density throughout erythroid differentiation contain binding sites for erythroid transcription factors and several factors not previously recognized as erythroid-specific factors. The functional importance of 5-hmC was demonstrated by impaired erythroid differentiation, with augmentation of myeloid potential, and disrupted 5-hmC patterning in leukemia patient-derived CD34+ stem/early progenitor cells with TET methylcytosine dioxygenase 2 (TET2) mutations. Thus, chemical conjugation and affinity purification of 5-hmC-enriched sequences followed by sequencing serve as resources for deciphering functional implications for gene expression during stem cell commitment and differentiation along a particular lineage.