Project description:To address how Csf3r and RUNX1 mutations in combination with CSF3 administration affect hematopoiesis in vitro, we performed hematopoietic expansion cultures in LODISH stem cell expansion medium. Lineage-negative Csfr-d715 BM cell cells were retrovirally transduced with the patient specific RUNX1-D171N (RHD) mutant or an empty vector control and subsequently treated with puromycin to select for the transduced cells. Lineage- c-Kit+ (LK) cells were FACS sorted in TRIzol 2, 5 and 9 days after puromycin selection and subsequently used for RNA isolation according to the manufacturer’s protocol. SMARTer Ultra Low Input RNA kit for sequencing (Clontech, v4 Cat# 634891) was used to generate cDNA. Sequencing libraries were generated using TruSeq Nano DNA Sample Preparation kits (Illumina, Cat# 20015964), according to the low sample protocol and paired-end sequenced on a HiSeq 2500 (Illumina).
Project description:In this study, we use pre-malignant cells from different Cebpa mutant acute myeloid leukemia (AML) models. We have used conditional KO models (CreLoxP) and isolated hematopoietic cells shortly after induction of recombination, in order to look at pre-leukemic cells, which have acquired the first hit, but not yet undergone full malignant transformation. We have sorted granulocyte-macrophage progenitors (GMPs) and the more immature population pre-granulocyte-macrophages (preGMs) from pre-leukemic mice. We analyzed gene-expression profiles in order to find deregulated genes, which make the cells more prone to undergo transformation.
Project description:Single cell lineage analysis was used to assess clonal genetic heterogeneity and functional aspects of AML HSPCs derived at diagnosis and relapse. To address inherent limitations of single cell analysis, we developed a unique high-resolution technique capable of following single cell-derived subclones of different HSPC subpopulations during the AML course. Each of these subclones was evaluated for chemo-resistance, in-vivo leukemogenic potential in Nod Scid Gamma (NSG) mice, mutational profile, and the subclone cell of origin identified using retrospective cell lineage reconstruction.
Project description:In this study, we use a conditional mouse model for Cebpa to investigate the significance of C/EBPα in HSCs. The frequency of HSCs is unaltered following deletion of C/EBPα, however, upon serial transplantations of either full BM or purified HSCs, the stem cells and stem cell activity is lost. This is not due to increased proliferation, but rather caused by a shift from quiescence to apoptosis with a resultant exhaustion of the stem cell pool. We identify direct C/EBPα target genes by combining genome-wide C/EBPα ChIP-seq analysis in stem and progenitor cells with gene expression data from HSC with and without C/EBPα. Furthermore, we explore the impact of C/EBPα on active and repressive histone modifications by doing functional genome-wide ChIP-seq analysis of H3K4Me3 and H3K27Me3 in stem and progenitor cells with and without C/EBPα. We have sorted HSCs from 3 Cebpaflox/flox and 4 Cebpaflox/flox;Mx1Cre mice 18 days after pIC injection.
Project description:Transcriptome analysis of epididymal white adipose tissue (WAT) depots in Ercc1 animals: To further elucidate the role of ERCC1 in WAT we scanned the transcriptome of 15 day old wt and Ercc1 epididymal WAT.
Project description:Background: Several genetic defects of the nucleotide excision repair (NER) pathway, including deficiency of the Excision Repair Cross-Complementing rodent repair deficiency, complementation group 1 (ERCC1), result in pre-mature aging, impaired growth, microcephaly and delayed development of the cerebellum. Such a phenotype also occurs in ERCC1-knockout mice which survive for up to 4 weeks after birth. Therefore, we analyzed cerebellar and hippocamapal transcriptomes of these animals at 3 weeks of age to identify the candidate mechanisms underlying brain consequences of reduced ERCC1 activity. Results: In the cerebellum, the most prominent change was upregulation of genes that are associated with gliosis. Although Purkinje cell degeneration has been reported in some mouse strains with NER impairment, Purkinje cell transcriptome was mostly unaffected by the ERCC1 knockout. In the hippocampus, the gliosis response was minimal. Instead, there was an extensive downregulation of genes related to lipid metabolism including several enzymes of the cholesterol biosynthesis pathway as well as lipoproteins and plasma membrane proteins. Reduced expression of the cholesterol biosynthesis pathway genes was also present in the neocortex of adult mice whose ERCC1 gene was replaced by a mutant allele with a partial activity. Conclusions: Downregulation of forebrain cholesterol biosynthesis genes is a newly identified consequence of ERCC1 deficiency. Its presence in adult mice suggests that it is not a secondary consequence of brain growth impairment. Instead, reduced cholesterol biosynthesis may contribute to such an impairment as well as affect function of mature synapses.
Project description:The XPF-ERCC1 endonuclease is required for repair of helix-distorting DNA damage and interstrand crosslinks. Here we have engineered a severe mutation in Ercc1 gene (in which the last 7 amino acids are missing; named as "Ercc1-delta") leading to extreme sensitivity to DNA crosslinks and progeria.To investigate whether a disturbance in growth and metabolism could explain the pronounced accelerated organismal deterioration seen in Ercc1 delta mice, we evaluated the liver transcriptome of 16-week-old wt and mutant mice (n=6). At this age, the Ercc1-delta mice have not yet become cachectic.