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: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.
Project description:Cord blood CD34+ hematopoietic precursors (3 donors) were control or HES6 shRNA (HES6 knockdown) transduced and cultured for four days in media containing SCF, TPO and EPO to drive differentiation towards megakaryocytes and erythroid cells. After four days four subpopulations were sorted for RNA isolation to research the effect of HES6 knockdown on gene expression. We sorted megakaryocytes (CD41+) and early (CD71+ CD235-) and late (CD71+ CD235+) erythroblasts (CD41-) and CD34- precursor cells (CD41- CD71- CD235- CD34-).
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.