Project description:Loss of Phf6 prevents the functional decline and immunophenotypic changes associated with age-related, long-term repopulating hematopoietic stem cell (LT-HSC) exhaustion. To identify the underlying molecular mechanisms that account for these differences, we performed RNA-seq profiling of LT-HSCs isolated from the bone marrow of Phf6 wild-type and knock-out, young (16-week-old) and aged (24-month-old) C57BL/6 mice. Our analysis revealed that LT-HSCs isolated from 24-month-old, Phf6 knockout mice retained the molecular signatures associated with young LT-HSCs whereas LT-HSCs isolated from aged, Phf6 wild-type mice acquired signatures consistent with HSC exhaustion. Mechanistically, these data revealed important roles for key metabolic pathways including glutathione metabolism and sterol biosynthesis, as well as cell-cell interaction and signaling pathways such as the interferon and TGF-beta responses.
Project description:The vulnerability of bone marrow hematopoiesis to perturbations of cholesterol metabolism is well documented, while the underlying cellular and molecular mechanisms remain poorly understood. Here we reveal a distinct cholesterol metabolic signature of hematopoietic stem cells (HSCs) within the hematopoietic compartment.To identify the phenotype switching and function variation in BM LT-HSCs with HCD treatment, we performed RNA-seq of LT-HSCs from the bone marrow of mice with or without3-month HCD treatment.
Project description:We have developed a new conditional transgenic mouse showing that MLL-ENL, at an endogenous-like expression level, induces leukemic transformation selectively in LT-HSCs. To investigate the molecular mechanism of leukemic transformation in LT-HSCs conditionally expressing MLL-ENL, we preliminarily performed comprehensive gene expression profiling of CreER-transduced LT-HSCs and ST-HSCs using cDNA microarray analysis. For initial screening of candidate genes invloved in the leukemic transformation, total RNA was extracted from colony-forming cells derived from LT-HSCs and ST-HSCs transduced with CreER or mock. Four samples were analyzed, and CreER-transduced LT/ST-HSC-derived cells were compared with mock-transduced LT/ST-HSC-derived cells, while CreER/mock-transduced LT-HSC-derived cells were compared with CreER/mock-transduced ST-HSC-derived cells.
Project description:We have developed a new conditional transgenic mouse showing that MLL-ENL, at an endogenous-like expression level, induces leukemic transformation selectively in LT-HSCs. To investigate the molecular mechanism of leukemic transformation in LT-HSCs conditionally expressing MLL-ENL, we preliminarily performed comprehensive gene expression profiling of CreER-transduced LT-HSCs and ST-HSCs using cDNA microarray analysis.
Project description:LRF, which is encoded by the ZBTB7A gene and formerly known as POKEMON (POK erythroid myeloid ontogenic factor), was originally identified as a PLZF (promyelocytic leukemia zinc finger) homologue interacting with BCL6 (B-cell lymphoma 6). LRF is a transcription factor that is broadly expressed in hematopoietic lineage cells, but its expression is particularly high in erythroblasts and germinal center (GC) B-cells. The goal of this study is to assess the effect of LRF loss on the LT-HSC transcriptome. Nine days after injection of adult mice with polyinosinic polycytidylic acid (pIpc) to activate Cre, total RNAs were isolated from double-sorted LT-HSCs from LRF Flox/+ Mx1-Cre+ and LRF Flox/Flox Mx1-Cre+ mice and processed for microarray analysis. We performed gene expression microarray analysis of FACS-sorted LT-HSCs (LSK IL7Ra-Flt3-CD150+CD48-) to assess the effect of Lrf loss on the LT-HSC transcriptome. Zbtb7a Flox/+ Mx1-Cre+ mice were used as a control to normalize the potential effects of Cre recombinase. LT-HSCs were FACS-sorted from three Lrf knockout (Zbtb7a Flox/Flox Mx1-Cre+) and two control (Zbtb7a Flox/+ Mx1-Cre+) mice, nine days after the first pIpC injection.
Project description:Analysis of HSCs from control and c-myc N-myc deficient long-term hematopoietic stem cells. HSCs lacking both c-myc and N-myc display increased apoptosis rates. Data provide insight into the molecular changes occuring upon complete loss of Myc activity, clarifying the resulting apoptotic mechanism and the role of Myc family proteins in HSCs. LT-HSC (Lin-Sca1+CD150+CD48-) cells were sorted from the BM of MxCre c-myc flox2 N-myc flox2 (experimental) and c-myc flox2 N-myc flox2 (control) mice 3 days after the last pI-pC injection. Each condition was analysed in triplicates, with each replicate consisting of a pool of 3 dKO mice or 2 control mice.