Acute loss of TET function results in aggressive myeloid cancer in mice [WGBS]
Ontology highlight
ABSTRACT: To evaluate the DNA methylation in LSK cells from the bone marrow of wildtype or Tet2/3 DKO mice. In order to address the impact of the loss of Tet2/3 proteins in DNA methylation in LSK cells, we compared by WGBS the methylome of wild and, Tet2/3 DKO LSK cells in bone marrow.
Project description:The study was a comparison of gene expression using RNA-seq. We analyzed the stem and progenitor cells from WT and Vav-cre+ Tet2fl/fl Flt3-ITD (T2F3) mice. We isolated stem cells LSK (lin- sca+ kit+) and granulocyte-macrophage progenitors GMP (lin- sca- kit+ fcgr+ cd34+) cells from bone marrow. Comparisons were made across genotypes WT vs. T2F3 and cell types LSK vs. GMP. Comparison of WT and Tet2-/-Flt3ITD bone marrow stem and progenitor cells.
Project description:We found PAD4, which is one of the transcriptional co-regulator by histone modification, was highly expressed in lineage-, Sca-1+, c-kit+ (termed as LSK) cells of mouse bone marrow. To find the target genes which are regulated by PAD4 in LSK cells, we analyzed gene expression in PAD4-deficient mouse as compared with wild-type mouse. Gene expression in wild-type and PAD4-deficient LSK cells
Project description:C/EBPalpha is a transcription factor critically involved in myeloid development and indispensable for formation of granulocytes. To track the cellular fate of stem and progenitor (LSK) cells, which express C/EBPalpha, we developed a mouse model expressing Cre recombinase from the Cebpa promoter and an inducible EYFP allele. We show that Cebpa/EYFP+ cells represent a significant subset of LSK cells, which predominantly give rise to myeloid cells in steady state hematopoiesis. C/EBPalpha induced a robust myeloid gene expression signature and downregulated E2A-induced regulators of early lymphoid development. In addition, Cebpa/EYFP+ cells comprise a fraction of early thymic progenitors (ETP) with robust myeloid potential. However, Cebpa/EYFP+ LSK and ETP cells retained the ability to develop into erythroid and T-lymphoid lineages, respectively. These findings support an instructive, but argue against a lineage restrictive role of C/EBPalpha in multipotent hematopoietic and thymic progenitors. We performed global gene expression profiling of double-sorted Cebpa/EYFP+ and Cebpa/EYFP- LSK cells of pooled Cebpa Cre/wt R26 EYFP reporter mice to identify differentially regulated genes in Cebpa+ versus Cebpa- LSK cells. RNA was isolated from three biological replicates of Cebpa/EYFP+ LSK cells and two biological replicates of Cebpa/EYFP- LSK cells. To determine if the identified genes were truly dependent on Cebpa expression, we also performed global gene expression profilling of Cebpa/EYFP+ and Cebpa/EYFP- fetal liver LSK cells of Cebpa Cre/fl R26 EYFP mice. Induction of Cebpa/Cre expression in these mice leads to Cre-mediated recombination of the floxed wt Cebpa allele resulting in a complete Cebpa knock-out. In this case, RNA was isolated from two biological replicates of either Cebpa/EYFP+ and Cebpa/EYFP- LSK cells. In addition, we included one biological replicate of Cebpa/EYFP+ and Cebpa/EYFP- fetal liver LSK cells of Cebpa Cre/wt R26 EYFP mice to determine the correlation of differentially regulated genes in bone marrow and fetal liver LSK cells.
Project description:Homeostatic hematopoietice stem cells (HSCs) with greater divisional history lose repopulating potential after very few cell divisions. Divisional history overrides both phenotype and immediate quiescence in determining functional activity. In GFP label retaining system GFP is progressively diluted when cells proceed through a cascade of divisions. We used a GFP label retaining system and performed microarray expression analyses to track the changes in the gene expression profile of bone marrow (BM) LSK cells that relates to divisional history during homeostasis. Chromatins are dynamically labeled in a double transgenic mouse (huCD34-tTA X Tet-O-H2B-GFP) by the expression of GFP tagged Histone2B. The expression is driven by a human CD34 promoter active specifically in all bone marrow (BM) hematopoietic stem and multi-potent progenitor cells. This is a pulse/chase Tet-off system where cells constantly label with GFP. Upon administration of Doxycyclin (Dox) to GFP labeled animals, further labeling is stopped during the chase period. With each round of cell division, the newly synthesized endogenous H2B will dilute H2B-GFP by one-half, whereas cells that don’t divide will retain GFP labeling. Therefore, the level of GFP reflects how many times cells have divided over the period of Dox treatment (chase). Animals were treated with Dox for 12 weeks starting at the age of 6-8 weeks. After chase, BM Lineage negative, Sca1+, Kit+ (LSK) cells with varying GFP levels were sorted for mRNA extraction. GFP levels were ranked from 0 to 4 based on the kinetic analysis of GFP fully labeled LSK cells and obvious peaks in the GFP histogram of LSK cells after Dox treatment. There is approximately 1-2 cell divisions between each level of GFP.
Project description:Tet enzymes (Tet1/2/3) convert 5-methylcytosine (5mC) to 5-hydroxymethylcytosine (5hmC). Tet1 and Tet2 mediate 5hmC generation in mouse embryonic stem cells (ESCs) and various embryonic and adult tissues. To investigate the effects of combined deficiency of Tet1 and Tet2 on pluripotency and development, we have generated Tet1 and Tet2 double knockout (DKO) ESCs and mice. DKO ESCs were depleted of 5hmC, but remained pluripotent with subtle defects in differentiation and changes in gene expression. Double mutant embryos and chimeras exhibited mid-gestation defects and postnatal DKO mice displayed partially penetrant neonatal lethality and stochastic perturbation of imprinting. Viable DKO animals developed normally to adulthood but had reduced 5hmC level, increased 5mC level and lacked 5hmC in germ cells. Nevertheless, DKO mice of both sexes were fertile with females having smaller ovaries and reduced fertility. Our data suggest that both Tet1 and Tet2 contribute to 5hmC levels during development. Their combined loss does not block differentiation and embryogenesis, but leads to partially penetrant embryonic and perinatal abnormalities and compromised viability. Moreover, the presence of substantial levels of 5hmC in DKO embryos and adult mice suggests a significant contribution of Tet3 in hydroxylation of 5mC during development. Methylation patterns in tissue samples from a series of wt and Tet1/Tet2 DKO embryos, neonates and adults were generated using methylated DNA immunoprecipitation with antibodies against 5mC (MeDIP) and 5hmC (hMeDIP) followed by deep sequencing.
Project description:Recent studies have shown that both TET2 mutation and JAK2V617F mutation are frequent in myeloproliferative neoplasms patients. The pathophysiological roles of each mutation have been elucidated in murine models, but the cooperative effect of the two mutations has not been elucidated yet. In this study, we examined the function of the cooperative effect of loss-of-TET2 function and JAK2V617F mutation in murine hematopoiesis. In this study, we utilized wild type (WT) mice, TET2 knock down (TET2KD) mice, JAK2V617F transgenic mice, double mutant mice. We transplanted 4 types of E14.5 fetal liver cells (WT, TET2KD, JAK2V617F, double mutant) into lethally irradiated mice. At 10-16 weeks post-transplantation, LSK cells from the BM of the recipients were collected, and gene expression analysis was performed. (WT,5 mice at 16 weeks; TET2KD, 5 mice at 10 weeks; JAK2V617F, 5 mice at 16 weeks; double mutant, 5 mice at 13 weeks)
Project description:Murine WBP1L-deficient (Wbp1l-/-) hematopoietic stem and progenitor cells engraft significantly better than wild-type (WT) cells in competitive transplantation assays. To analyze the mechanism, Wbp1l-/- or WT bone marrow cells (both Ly5.2+Ly5.1-) were each mixed 1:1 with WT competitor cells (Ly5.2+Ly5.1+) and the mixture was transplanted into the lethally irradiated recipient mice. 22 weeks after the transplantation the donor Ly5.2+Ly5.1- LSK cells (Wbp1l-/- or WT) were purified from the bone marrow of recipient mice, RNA was extracted and subjected to RNA sequencing.
Project description:We compared gene expression differences in Lyl-1 knockout vs wildtype LMPPs KO allele described in Pub Med ID: 21387538 LMPPS were purified as Lineage-negative, Sca-1+ c-Kit+ (LSK) and Flt3-high from both Lyl1-null and WT mice on C57Bl/6 background