Similar Datasets
Project description:This SuperSeries is composed of the SubSeries listed below.
2022-11-11 | GSE191163 | GEO
Project description:Hematopoietic stem cells (HSCs) balance self-renewal and differentiation to maintain hematopoietic fitness throughout life. In steady-state conditions, HSC exhaustion is prevented by the maintenance of most HSCs in a quiescent state, with cells entering the cell cycle only occasionally. HSC quiescence is regulated by retinoid and fatty-acid ligands of transcriptional factors of the nuclear retinoid X receptor (RXR) family. Here, we show that dual deficiency for hematopoietic RXRa and RXRb induces HSC exhaustion, myeloid cell/megakaryocyte differentiation, and myeloproliferative-like disease. RXRa and RXRb maintain HSC quiescence, survival, and chromatin compaction; moreover, transcriptome changes in RXRa;RXRb-deficient HSCs include premature acquisition of an aging-like HSC signature, MYC pathway upregulation, and RNA intron retention. Fitness loss and associated RNA transcriptome and splicing alterations in RXRa;RXRb-deficient HSCs are prevented by Myc haploinsufficiency. Our study reveals the critical importance of RXRs for the maintenance of HSC fitness and their protection from premature aging.
2022-11-11 | GSE191161 | GEO
Project description:Hematopoietic stem cells (HSCs) balance self-renewal and differentiation to maintain hematopoietic fitness throughout life. In steady-state conditions, HSC exhaustion is prevented by the maintenance of most HSCs in a quiescent state, with cells entering the cell cycle only occasionally. HSC quiescence is regulated by retinoid and fatty-acid ligands of transcriptional factors of the nuclear retinoid X receptor (RXR) family. Here, we show that dual deficiency for hematopoietic RXRa and RXRb induces HSC exhaustion, myeloid cell/megakaryocyte differentiation, and myeloproliferative-like disease. RXRa and RXRb maintain HSC quiescence, survival, and chromatin compaction; moreover, transcriptome changes in RXRa;RXRb-deficient HSCs include premature acquisition of an aging-like HSC signature, MYC pathway upregulation, and RNA intron retention. Fitness loss and associated RNA transcriptome and splicing alterations in RXRa;RXRb-deficient HSCs are prevented by Myc haploinsufficiency. Our study reveals the critical importance of RXRs for the maintenance of HSC fitness and their protection from premature aging.
2022-11-11 | GSE191162 | GEO
Project description:Hematopoietic stem cells (HSCs) maintain homeostasis and fitness by balancing self-renewal and differentiation. Alterations to the symmetry of HSC divisions reduce quiescence and induce myeloid/megakaryocyte-biased hematopoiesis. Here, we show that HSC self-renewal, fitness, and function are preserved by the master transcription factor retinoid X receptor (RXR). We demonstrate that dual lack of hematopoietic RXRα and RXRβ induces HSC asymmetric cell division resulting in HSC exhaustion and age-associated myeloproliferative disease. Characterization of transcriptomic and epigenetic changes in RXR-deficient HSCs demonstrated chromatin opening, acquisition of a premature aging-like HSC signature, MYC pathway upregulation, and RNA intron retention. Myc haploinsufficiency completely prevents the loss of RXR-deficient HSC activity. Our study unveils the critical relevance of RXR for HSC homeostasis and fitness.
2022-11-16 | GSE199936 | GEO
Project description:Hematopoietic stem cells (HSCs) maintain homeostasis and fitness by balancing self-renewal and differentiation. Alterations to the symmetry of HSC divisions reduce quiescence and induce myeloid/megakaryocyte-biased hematopoiesis. Here, we show that HSC self-renewal, fitness, and function are preserved by the master transcription factor retinoid X receptor (RXR). We demonstrate that dual lack of hematopoietic RXRα and RXRβ induces HSC asymmetric cell division resulting in HSC exhaustion and age-associated myeloproliferative disease. Characterization of transcriptomic and epigenetic changes in RXR-deficient HSCs demonstrated chromatin opening, acquisition of a premature aging-like HSC signature, MYC pathway upregulation, and RNA intron retention. Myc haploinsufficiency completely prevents the loss of RXR-deficient HSC activity. Our study unveils the critical relevance of RXR for HSC homeostasis and fitness.
2022-11-16 | GSE199935 | GEO
Project description:Hematopoietic stem cells (HSCs) maintain homeostasis and fitness by balancing self-renewal and differentiation. Alterations to the symmetry of HSC divisions reduce quiescence and induce myeloid/megakaryocyte-biased hematopoiesis. Here, we show that HSC self-renewal, fitness, and function are preserved by the master transcription factor retinoid X receptor (RXR). We demonstrate that dual lack of hematopoietic RXRα and RXRβ induces HSC asymmetric cell division resulting in HSC exhaustion and age-associated myeloproliferative disease. Characterization of transcriptomic and epigenetic changes in RXR-deficient HSCs demonstrated chromatin opening, acquisition of a premature aging-like HSC signature, MYC pathway upregulation, and RNA intron retention. Myc haploinsufficiency completely prevents the loss of RXR-deficient HSC activity. Our study unveils the critical relevance of RXR for HSC homeostasis and fitness.
2022-11-16 | GSE199934 | GEO
Project description:Quiescence is a fundamental property that maintains hematopoietic stem cell (HSC) potency throughout life. Quiescent HSCs are thought to rely on glycolysis for their energy, but the overall metabolic properties of HSCs remain elusive. Using combined approaches, including single-cell RNA sequencing (RNA-seq), we show that mitochondrial membrane potential (MMP) distinguishes quiescent from cycling-primed HSCs. We found that primed, but not quiescent, HSCs relied readily on glycolysis. Notably, in vivo inhibition of glycolysis enhanced the competitive repopulation ability of primed HSCs. We further show that HSC quiescence is maintained by an abundance of large lysosomes. Repression of lysosomal activation in HSCs led to further enlargement of lysosomes while suppressing glucose uptake. This also induced increased lysosomal sequestration of mitochondria and enhanced the competitive repopulation ability of primed HSCs by over 90-fold in vivo. These findings show that restraining lysosomal activity preserves HSC quiescence and potency and may be therapeutically relevant.
| S-EPMC8075247 | biostudies-literature
Project description:Hematopoietic stem cells (HSC) self-renew to sustain stem cell pools and differentiate to generate all types of blood cells. HSCs remain in quiescence to sustain their long-term self-renewal potential. It remains unclear whether protein quality control is required for stem cells in quiescence when RNA content, protein synthesis, and metabolic activities are profoundly reduced. Here, we report that protein quality control via endoplasmic reticulum-associated degradation (ERAD) governs the function of quiescent HSCs. The Sel1L/Hrd1 ERAD genes are enriched in the quiescent and inactive HSCs, and conditional knockout of Sel1L in hematopoietic tissues drives HSCs to hyperproliferation, which leads to complete loss of HSC self-renewal and HSC depletion. Mechanistically, ERAD deficiency via Sel1L knockout leads to activation of mammalian target of rapamycin (mTOR) signaling. Furthermore, we identify Ras homolog enriched in brain (Rheb), an activator of mTOR, as a novel protein substrate of Sel1L/Hrd1 ERAD, which accumulates upon Sel1L deletion and HSC activation. Importantly, inhibition of mTOR, or Rheb, rescues HSC defects in Sel1L knockout mice. Protein quality control via ERAD is, therefore, a critical checkpoint that governs HSC quiescence and self-renewal by Rheb-mediated restriction of mTOR activity.
| S-EPMC7770563 | biostudies-literature
Project description:Hematopoietic stem cell (HSC) utilizes its quiescence feature to combat exhaustion for lifetime blood cell supply. To date, how certain chromatin architecture and subsequent transcription profile permit HSC quiescence remains unclear. Here, we show an essential role of chromatin remodeler zinc finger HIT-type containing 1 (Znhit1) in maintaining HSC quiescence. We find that loss of Znhit1 leads to exhaustion of stem cell pool and impairment of hematopoietic function. Mechanically, Znhit1 determines the chromatin accessibility at distal enhancers of HSC quiescence genes, including Pten, Fstl1, and Klf4, for sustained transcription and consequent PI3K-Akt signaling inhibition. Moreover, Znhit1-Pten-PI3K-Akt axis also participates in controlling myeloid expansion and B-lymphoid specification. Our findings therefore identify a dominant role of Znhit1-mediated chromatin remodeling in preserving HSC function for hematopoietic homeostasis.
| S-EPMC7685981 | biostudies-literature
Project description:MLL5 is a novel trithorax group gene and a candidate tumor suppressor gene located within a 2.5-Mb interval of chromosome band 7q22 that frequently is deleted in human myeloid malignancy. Here we show that inactivation of the Mll5 gene in mice results in a 30% reduction in the average representation of hematopoietic stem cells and in functional impairment of long-term hematopoietic repopulation potential under competitive conditions. Bone marrow cells from Mll5-deficient mice were defective in spleen colony-forming assays, and the mutant mice showed enhanced susceptibility to 5-fluorouracil-induced myelosuppression. Heterozygous and homozygous Mll5 mutant mice did not spontaneously develop hematologic cancers, and loss of Mll5 did not alter the phenotype of a fatal myeloproliferative disorder induced by oncogenic Kras in vivo. Collectively, the data reveal an important role for Mll5 in HSC homeostasis and provide a basis for further studies to explore its role in leukemogenesis.
| S-EPMC2644073 | biostudies-literature