Project description:Ecotropic viral integration site 1 (EVI1/MECOM) overexpression is common in myeloid malignancies. We present a new Evi1 transgenic mouse model with inducible expression in hematopoietic stem cells (HSCs) and progenitor cells (HPCs) at lower levels. Upon exogenous Evi1 induction, mice displayed anemia, thrombocytopenia, lymphopenia, and dysplasia in erythroid and megakaryocyte cells with a significant expansion of committed myeloid progenitor cells, resembling human Myelodysplastic syndrome/Myeloproliferative neoplasm (MDS/MPN)-like disease. Methods: Lin-C-Kit+ cells were isolated from 3 pairs of WT and Evi1 overexpressing mice. Around 1X106 Lin-C-Kit+ cells were harvested from each mouse. Then the cells were lysated by Trizol and total RNA was extracted by phenol-chloroform. Results: Molecular pathways altered in Lin-C-Kit+ cells from Evi1-OE mice. Conclusions: Multiple molecular pathways changed in Evi1 overexpressing hematopoietic stem and progenitor cells.
Project description:Ecotropic viral integration site 1 (EVI1/MECOM) overexpression is common in myeloid malignancies. We present a new Evi1 transgenic mouse model with inducible expression in hematopoietic stem cells (HSCs) and progenitor cells (HPCs) at lower levels. Upon exogenous Evi1 induction, mice displayed anemia, thrombocytopenia, lymphopenia, and dysplasia in erythroid and megakaryocyte cells with a significant expansion of committed myeloid progenitor cells, resembling human Myelodysplastic syndrome/Myeloproliferative neoplasm (MDS/MPN)-like disease. Methods: Lin-C-Kit+ cells were isolated from 2 Evi1 overexpressing mice for CUT&RUN assay using flag antibody and IgG. Lin-C-Kit+ cells were isolated from 2 pair of WT mice and Evi1 overexpressing mice for CUT&RUN assay using H3K27me3 antibody.Around 5X105 Lin-C-Kit+ cells for each group were used in CUT&RUN assay. About 10 ng of the purified CUT&RUN DNA was used for preparation of multiplexed libraries with the NEB Ultra II DNA Library Prep Kit per manufacturer's instruction (NEB #E7103). Sequencing was conducted using an Illumina NextSeq 500 Sequencing System. Results: Molecular pathways altered in Lin-C-Kit+ cells from Evi1-OE mice. Conclusions: Evi1 has a special binding profiling in Lin-C-Kit+ cells. The modification profile of H3K27me3 was altered in Evi1-OE hematopoietic stem and progenitor cells.
Project description:The transcription factor Evi1 is essential for the formation and maintenance of hematopoietic stem cells, and induces clonal dominance with malignant progression upon constitutive activation by chromosomal rearrangements or transgene integration events. To understand the immediate and adaptive response of primary murine hematopoietic cells to the transcriptional upregulation of Evi1, we developed an inducible lentiviral vector system with a robust expression switch. We found that Evi1 delays differentiation and promotes survival in myeloid culture conditions, orchestrating a battery of genes involved in stemness (Aldh1a1, Ly6a [Sca1], Abca1, Epcam, among others). Importantly, Evi1 suppresses Cyclins and Cyclin-dependent kinases (Cdk), while it upregulates Cdk inhibitors, inducing quiescence in various proliferation-inducing cytokine conditions and operating in a strictly dose-dependent manner. Hematopoietic cells with persisting Evi1-induction tend to adopt a relatively low expression level. We thus classify Evi1 as a dormancy-inducing oncogene, likely requiring epigenetic and genetic compensation for cell expansion and malignant progression. Lin- Rosa26rtTA cells were isolated, transduced in S3F11 cytokines, induced the next day with DOX [1 μg/ml] and 20 hours later sorted for negative/low or highly EGFP expressing cells, from which total RNA was extraced and subjected to Microarray Analysis
Project description:The transcription factor Evi1 is essential for the formation and maintenance of hematopoietic stem cells, and induces clonal dominance with malignant progression upon constitutive activation by chromosomal rearrangements or transgene integration events. To understand the immediate and adaptive response of primary murine hematopoietic cells to the transcriptional upregulation of Evi1, we developed an inducible lentiviral vector system with a robust expression switch. We found that Evi1 delays differentiation and promotes survival in myeloid culture conditions, orchestrating a battery of genes involved in stemness (Aldh1a1, Ly6a [Sca1], Abca1, Epcam, among others). Importantly, Evi1 suppresses Cyclins and Cyclin-dependent kinases (Cdk), while it upregulates Cdk inhibitors, inducing quiescence in various proliferation-inducing cytokine conditions and operating in a strictly dose-dependent manner. Hematopoietic cells with persisting Evi1-induction tend to adopt a relatively low expression level. We thus classify Evi1 as a dormancy-inducing oncogene, likely requiring epigenetic and genetic compensation for cell expansion and malignant progression. Lin- Rosa26rtTA cells were isolated, transduced either with pRRL.PPT.Tet.Evi1.IRES.EGFP.pre or with the pRRL.PPT.Tet.EGFP.pre control vector in S3F11 cytokines, induced the next day with DOX [1 μg/ml] and 20 hours later sorted for EGFP expressing cells, from which total RNA was extraced and subjected to Microarray Analysis.
Project description:A transcriptome study in mouse hematopoietic stem cells was performed using a sensitive SAGE method, in an attempt to detect medium and low abundant transcripts expressed in these cells. Among a total of 31,380 unique transcript, 17,326 (55%) known genes were detected, 14,054 (45%) low-copy transcripts that have no matches to currently known genes. 3,899 (23%) were alternatively spliced transcripts of the known genes and 3,754 (22%) represent anti-sense transcripts from known genes.
Project description:A transcriptome study in mouse hematopoietic stem cells was performed using a sensitive SAGE method, in an attempt to detect medium and low abundant transcripts expressed in these cells. Among a total of 31,380 unique transcript, 17,326 (55%) known genes were detected, 14,054 (45%) low-copy transcripts that have no matches to currently known genes. 3,899 (23%) were alternatively spliced transcripts of the known genes and 3,754 (22%) represent anti-sense transcripts from known genes. Mouse hematopoietic stem cells were purified from bone marrow cells using negative and positive selection with a Magnetic-Activated Cell Sorter (MACS). total RNA and mRNA were purified from the purified cells using Trizol reagent and magnetic oligo dT beads. Double strand cDNAs were synthesized using a cDNA synthesis kit and anchored oligo dT primers. After NlaIII digestion, 3’ cDNAs were isolated and amplified through 16-cycle PCR. SAGE tags were released from the 3’ cDNA after linker ligation. Ditags were formed, concatemerized and cloned into a pZERO vector. Sequencing reactions were performed with the ET sequencing terminator kit. Sequences were collected using a Megabase 1000 sequencer. SAGE tag sequences were extracted using SAGE 2000 software.