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Filename: controllers/Detail.php
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File: /var/www/html/application/controllers/Detail.php
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In mammalian cells, cytosines found within cytosine guanine dinucleotides can be methylated to 5-methylcytosine (5-mC) by DNA methyltransferases and further oxidized by the Ten-eleven translocation dioxygenase (TET) enzymes to 5-hydroxymethylcytosine (5-hmC). We have previously shown that hematopoietic stem and progenitor cells (HSPCs) with TET2 mutations have aberrant 5-hmC distribution and less erythroid differentiation potential. However, these experiments were performed under standard tissue culture conditions with 21% oxygen (O2), whereas HSPCs in human bone marrow reside in ∼1% O2. Therefore, to model human erythropoiesis more accurately, we compared 5-hmC distribution and gene expression in hypoxic vs normoxic conditions. Despite TET enzymes having limited O2 as a substrate in hypoxia, 5-hmC peaks were more numerous and pronounced than in normoxia. Among the TET genes, TET3 was upregulated specifically in hypoxia. We identified 2 HIF-1 binding sites in TET3 by chromatin immunoprecipitation of HIF-1α followed by sequencing, and TET3 upregulation was abrogated with deletion of both sites, indicating that TET3 is a direct HIF-1 target. Finally, we showed that loss of one or both of these HIF-1 binding sites in K562 cells disrupted erythroid differentiation in hypoxia and lowered cell viability. This work provides a molecular link between O2 availability, epigenetic modification of chromatin, and erythroid differentiation.
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http://dx.doi.org/10.1182/bloodadvances.2020001535 | DOI Listing |
J Biol Chem
December 2024
University of Stuttgart, Institute of Biomedical Genetics, Department of Eukaryotic Genetics, Allmandring 31, 70569 Stuttgart, Germany. Electronic address:
Erythropoiesis is controlled by transcription factors that recruit epigenetic cofactors to establish and maintain erythrocyte-specific gene expression patterns while repressing alternative lineage commitment. The transcription factor TAL1 is critical for establishing erythroid gene expression. It acts as an activator or repressor of genes, depending on associated epigenetic cofactors.
View Article and Find Full Text PDFStem Cells Dev
December 2024
Department of Neurology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
Ninety-nine percent of alpha-synuclein (α-syn) in the human body is distributed in erythrocytes. However, the role that α-syn plays in erythropoiesis remains unclear. To determine the effect of α-syn on erythroid differentiation, the erythroid cells, derived from human CD34+ progenitors in the umbilical cord, were cultured in a system composed of a series of cytokines and harvested after 6 days.
View Article and Find Full Text PDFStem Cell Res Ther
December 2024
Department of Pathology, Qingdao Municipal Hospital Group, 1 Jiaozhou Road, Qingdao, 266011, Shandong, China.
Background: The challenge of expanding haematopoietic stem/progenitor cells (HSPCs) in vitro has limited their clinical application. Human hair follicle mesenchymal stem cells (hHFMSCs) can be reprogrammed to generate intermediate stem cells by transducing OCT4 (hHFMSCs) and pre-inducing with FLT3LG/SCF, and differentiated into erythrocytes. These intermediate cells exhibit gene expression patterns similar to pre-HSCs, making them promising for artificial haematopoiesis.
View Article and Find Full Text PDFAccumulation of free α-globin is a critical factor in the pathogenesis of β-thalassemia. Autophagy plays a crucial role in clearing toxic free α-globin, thereby reducing disease severity. However, the impact of natural mutations in autophagy-related genes (ATGs) on the phenotypic variability of β-thalassemia remains unclear.
View Article and Find Full Text PDFPLoS One
December 2024
Dept. of Human and Animal Cell Lines, Leibniz-Institute DSMZ, Braunschweig, Germany.
Homeobox genes encode transcription factors which organize differentiation processes in all tissue types including the hematopoietic compartment. Recently, we have reported physiological expression of TALE-class homeobox gene IRX1 in early myelopoiesis restricted to the megakaryocyte-erythroid-progenitor stage and in early B-cell development to the pro-B-cell stage. In contrast, sister homeobox genes IRX2, IRX3 and IRX5 are aberrantly activated in the corresponding malignancies acute myeloid leukemia (AML) and B-cell progenitor acute lymphoid leukemia.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!