Project description:CFU-PreB colonies are reduced in number and size in Hspa9+/- mice compared to wildtype littermates. We compared the expression profiles of these colonies to gain insight into the mechanism driving this difference. HSPA9 is located on chromosome 5q31.2 in humans, a region that is commonly deleted in patients with myeloid malignancies [del(5q)], including myelodysplastic syndromes (MDS). HSPA9 expression is reduced by 50% in patients with del(5q)-associated MDS, consistent with haploinsufficient levels. Zebrafish mutants and knockdown studies in human and mouse cells have implicated a role for HSPA9 in hematopoiesis. To comprehensively evaluate the effects of Hspa9 haploinsufficiency on hematopoiesis, we generated an Hspa9 knockout mouse model. While homozygous knockout of Hspa9 is embryonic lethal, mice with heterozygous deletion of Hspa9 (Hspa9+/-) are viable and have a 50% reduction in Hspa9 expression. Hspa9+/- mice have normal basal hematopoiesis and do not develop MDS. However, Hspa9+/- mice have a cell-intrinsic reduction in bone marrow CFU-PreB colony formation without alterations in the number of B-cell progenitors in vivo, consistent with a functional defect in Hspa9+/- B-cell progenitors. We further reduced Hspa9 expression (<50%) using RNAi and observe reduced B-cell progenitors in vivo, indicating that appropriate levels (≥50%) of Hspa9 are required for normal B-lymphopoiesis in vivo. Knockdown of Hspa9 in an IL-7 dependent mouse B-cell line reduced Stat5 phosphorylation following IL-7 receptor stimulation, supporting a role for Hspa9 in Stat5 signaling in B-cells. Collectively, these data implicate a role for Hspa9 in B-lymphopoiesis and Stat5 activation downstream of IL-7 signaling. Bone marrow cells from 5 Hspa9+/+ and 5 Hspa9+/- mice were independently cultured in CFU-PreB methylcellulose medium for 7 days. PreB colonies were isolated and B220+ cells were flow sorted for RNA isolation.
Project description:CFU-PreB colonies are reduced in number and size in Hspa9+/- mice compared to wildtype littermates. We compared the expression profiles of these colonies to gain insight into the mechanism driving this difference. HSPA9 is located on chromosome 5q31.2 in humans, a region that is commonly deleted in patients with myeloid malignancies [del(5q)], including myelodysplastic syndromes (MDS). HSPA9 expression is reduced by 50% in patients with del(5q)-associated MDS, consistent with haploinsufficient levels. Zebrafish mutants and knockdown studies in human and mouse cells have implicated a role for HSPA9 in hematopoiesis. To comprehensively evaluate the effects of Hspa9 haploinsufficiency on hematopoiesis, we generated an Hspa9 knockout mouse model. While homozygous knockout of Hspa9 is embryonic lethal, mice with heterozygous deletion of Hspa9 (Hspa9+/-) are viable and have a 50% reduction in Hspa9 expression. Hspa9+/- mice have normal basal hematopoiesis and do not develop MDS. However, Hspa9+/- mice have a cell-intrinsic reduction in bone marrow CFU-PreB colony formation without alterations in the number of B-cell progenitors in vivo, consistent with a functional defect in Hspa9+/- B-cell progenitors. We further reduced Hspa9 expression (<50%) using RNAi and observe reduced B-cell progenitors in vivo, indicating that appropriate levels (≥50%) of Hspa9 are required for normal B-lymphopoiesis in vivo. Knockdown of Hspa9 in an IL-7 dependent mouse B-cell line reduced Stat5 phosphorylation following IL-7 receptor stimulation, supporting a role for Hspa9 in Stat5 signaling in B-cells. Collectively, these data implicate a role for Hspa9 in B-lymphopoiesis and Stat5 activation downstream of IL-7 signaling.
Project description:To better understand the molecular bases of the oncogenic cooperation between trisomy 21 and RAS/MAPK pathway activation, KRASG12D was overexpressed in wild-type (WT) or partially trisomic (Ts1Rhr) bone marrow cells. Transduced mCherry-positive murine B cell progenitors were platted in methylcellulose to form B cell precursors colonies (CFU-preB). After a week, B220+/CD19+/CD25- B cells were harvested to perform RNA-sequencing experiments.
Project description:Knockdown of HSPA9 causes a dose-dependent decrease in erythroid maturation of CD34+ cells differentiated in culture. Due to differences in the degree of differentiation, a more homogeneous population was selected for using FACS and the gene expression profile of these cells was compared. We used a lentiviral vector (pLKO.1) expressing short hairpin RNAs targeting either luciferase (control shLUC) or HSPA9 (shHSPA9-433) to knock down expression of HSPA9. We isolated CD34+ cells from human cord blood (Day 0), transduced cells with a lentiviral vector (Day 1), selected for transduced cells with puromycin and differentiated them in erythroid culture media before FACS isolation of the CD34+/CD71- population (Day 5). Four independent CD34+ populations were isolated, differentiated and sorted for biologic replicates.
Project description:We studied the role of the stable Igh mRNA in Igh chain check point. Here we generated RNA-seq data from sorted ProB (CD19+B220+c-Kit+CD25-) and PreB (CD19+B220+c-Kit-CD25+) populations from Bone marrow of mice.
Project description:Lung resident MSCs were isolated from a deidentified donor. After ~14-day culture, individual colonies were isolated using a cloning ring approach. Individual colonies were separately expanded and the cells at passage 4 were collected for total RNA isolation.
Project description:Burst-forming unit-erythroid (BFU-E) and colony-forming unit-erythroid (CFU-E) cells are erythroid progenitors traditionally defined by colony assays. We developed a flow cytometry-based strategy for isolating human BFU-E and CFU-E cells based on the changes in expression of cell surface markers during in vitro erythroid cell culture. BFU-E and CFU-E are characterized by CD45+GPA-IL-3R-CD34+CD36-CD71low and CD45+GPA-IL-3R-CD34-CD36+CD71high phenotypes, respectively. Colony assays validated phenotypic assignment giving rise to BFU-E and CFU-E colonies, both at a purity ~90%. The BFU-E colony forming ability of CD45+GPA-IL-3R-CD34+CD36-CD71low cells required SCF and erythropoietin, while the CFU-E colony forming ability of CD45+GPA-IL-3R-CD34-CD36+CD71high cells required only erythropoietin. Bioinformatic analysis of the RNA-seq data revealed unique transcriptomes in each differentiation stage. The sorting strategy was validated in uncultured primary cells isolated from bone marrow and peripheral blood, indicating that marker expression is not an artifact of in vitro cell culture, but represents an in vivo characteristic of erythroid progenitor populations. The ability to isolate highly pure human BFU-E and CFU-E progenitors will enable detailed cellular and molecular characterization of these distinct progenitor populations and define their contribution to disordered erythropoiesis in inherited and acquired hematological disease. Our data provide important resource for future studies.
Project description:Using RNA-seq technology, we quantitatively determined the expression profile of microRNAs during mouse terminal erythroid differentiation. CFU-E erythroid progenitors were isolated from E14.5 fetal liver as the Ter119, B220, Mac-1, CD3 and Gr-1 negative, C-Kit positive and 20% high CD71 population. Mature Ter119+ erythroblasts were isolated from E14.5 fetal liver as C-Kit negative and Ter119 positive population. Consistent with nuclear condensation and global gene expression shut down during terminal erythroid differentiation, we found that the majority of microRNAs are downregulated in more mature Ter119+ erythroblasts compared with CFU-E erythroid progenitors.
Project description:Single cell-derived colonies were obtained by sorting 21 days fetal Rat calvaria cells into microtitre wells using flow cytometry. Colonies were categorized according to a limited gene expression profiling for a specific bone (osteocalcin) and a specific adipocyte (adipsin) marker by real-time PCR. Colonies expressing neither, one or both bone and adipocyte markers are in the sample set. Microarray analysis will address the global gene expression profiles of CFU-O (bone marker only), CFU-F (neither bone nor adipocyte marker) and CFU-bipotential (both markers) derived from single cells. CFU-A (adipocyte marker only) samples are also available for analysis if warranted. Keywords: other
Project description:Knockdown of HSPA9 causes a dose-dependent decrease in erythroid maturation of CD34+ cells differentiated in culture. Due to differences in the degree of differentiation, a more homogeneous population was selected for using FACS and the gene expression profile of these cells was compared. We used a lentiviral vector (pLKO.1) expressing short hairpin RNAs targeting either luciferase (control shLUC) or HSPA9 (shHSPA9-433) to knock down expression of HSPA9.