PU.1 enforces quiescence and limits hematopoietic stem cell expansion during inflammatory stress
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA994151 | ENA |
REPOSITORIES: ENA
Dataset's files
| Action | DRS | |||
|---|---|---|---|---|
| SRR25250538.fastq.gz | Fastqsanger.gz | |||
| SRR25250539.fastq.gz | Fastqsanger.gz | |||
| SRR25250540.fastq.gz | Fastqsanger.gz | |||
| SRR25250541.fastq.gz | Fastqsanger.gz |
Items per page: 5 1 - 4 of 4 |
Similar Datasets
Project description:Hematopoietic stem cells (HSCs) are capable of entering the cell cycle to replenish the blood system in response to inflammatory cues; however, excessive proliferation in response to chronic inflammation can lead to either HSC attrition or expansion. The mechanism(s) that limit HSC proliferation and expansion triggered by inflammatory signals are poorly defined. Here, we show that long-term HSCs (HSCLT) rapidly repress protein synthesis and cell cycle genes following treatment with the proinflammatory cytokine interleukin (IL)-1. This gene program is associated with activation of the transcription factor PU.1 and direct PU.1 binding at repressed target genes. Notably, PU.1 is required to repress cell cycle and protein synthesis genes, and IL-1 exposure triggers aberrant protein synthesis and cell cycle activity in PU.1-deficient HSCs. These features are associated with expansion of phenotypic PU.1-deficient HSCs. Thus, we identify a PU.1-dependent mechanism triggered by innate immune stimulation that limits HSC proliferation and pool size. These findings provide insight into how HSCs maintain homeostasis during inflammatory stress.
2023-07-27 | GSE237192 | GEO
Project description:Hematopoietic stem cells (HSCs) are capable of entering the cell cycle to replenish the blood system in response to inflammatory cues; however, excessive proliferation in response to chronic inflammation can lead to either HSC attrition or expansion. The mechanism(s) that limit HSC proliferation and expansion triggered by inflammatory signals are poorly defined. Here, we show that long-term HSCs (HSCLT) rapidly repress protein synthesis and cell cycle genes following treatment with the proinflammatory cytokine interleukin (IL)-1. This gene program is associated with activation of the transcription factor PU.1 and direct PU.1 binding at repressed target genes. Notably, PU.1 is required to repress cell cycle and protein synthesis genes, and IL-1 exposure triggers aberrant protein synthesis and cell cycle activity in PU.1-deficient HSCs. These features are associated with expansion of phenotypic PU.1-deficient HSCs. Thus, we identify a PU.1-dependent mechanism triggered by innate immune stimulation that limits HSC proliferation and pool size. These findings provide insight into how HSCs maintain homeostasis during inflammatory stress.
| S-EPMC8056754 | biostudies-literature
Project description:To guarantee blood supply throughout adult life hematopoietic stem cells (HSCs) need to carefully balance between self-renewing cell divisions and quiescence. Identification of genes controlling HSC self-renewal is of utmost importance given that HSCs are the only stem cells with broad clinical applications. Transcription factor PU.1 is one of the major regulators of myeloid and lymphoid development. Recent reports suggest that PU.1 mediates its functions via gradual expression level changes rather than binary on/off states. So far, this has not been considered in any study of HSCs and thus, PU.1’s role in HSC function has remained largely unclear. Here we demonstrate using hypomorphic mice with an engineered disruption of an autoregulatory feedback loop that decreased PU.1 levels resulted in loss of key HSC functions, all of which could be fully rescued by restoration of proper PU.1 levels via a human PU.1 transgene. Mechanistically, we found excessive HSC cell divisions and altered expression of cell cycle regulators whose promoter regions were bound by PU.1 in normal HSCs. Adequate PU.1 levels were maintained by a mechanism of direct autoregulation restricted to HSCs through a physical interaction of a -14kb enhancer with the proximal promoter. Our findings identify PU.1 as novel regulator controling the switch between cell division and quiescence in order to prevent exhaustion of HSCs. Given that even moderate level changes greatly impact stem cell function, our data suggest important therapeutic implications for leukemic patients with reduced PU.1 levels. Moreover, we provide first proof, that autoregulation of a transcription factor, PU.1, has a crucial function in vivo. We anticipate that our concept of how autoregulation forms an active chromosomal conformation will impact future research on transcription factor networks regulating stem cell fate. HSCs of Pu.1 knock-in (PU.1ki/ki) mice were used for RNA extraction and hybridization on Affymetrix microarrays. We compared these microarray samples with the corresponding wild type.
2011-12-01 | E-GEOD-33031 | biostudies-arrayexpress
Project description:Tristetraprolin Limits Age-related Expansion of Myeloid-Derived Suppressor Cells
| PRJNA868308 | ENA
Project description:IL-7-dependent STAT1 activation limits homeostatic CD4+ T cell expansion
| PRJNA417271 | ENA
Project description:To guarantee blood supply throughout adult life hematopoietic stem cells (HSCs) need to carefully balance between self-renewing cell divisions and quiescence. Identification of genes controlling HSC self-renewal is of utmost importance given that HSCs are the only stem cells with broad clinical applications. Transcription factor PU.1 is one of the major regulators of myeloid and lymphoid development. Recent reports suggest that PU.1 mediates its functions via gradual expression level changes rather than binary on/off states. So far, this has not been considered in any study of HSCs and thus, PU.1’s role in HSC function has remained largely unclear. Here we demonstrate using hypomorphic mice with an engineered disruption of an autoregulatory feedback loop that decreased PU.1 levels resulted in loss of key HSC functions, all of which could be fully rescued by restoration of proper PU.1 levels via a human PU.1 transgene. Mechanistically, we found excessive HSC cell divisions and altered expression of cell cycle regulators whose promoter regions were bound by PU.1 in normal HSCs. Adequate PU.1 levels were maintained by a mechanism of direct autoregulation restricted to HSCs through a physical interaction of a -14kb enhancer with the proximal promoter. Our findings identify PU.1 as novel regulator controling the switch between cell division and quiescence in order to prevent exhaustion of HSCs. Given that even moderate level changes greatly impact stem cell function, our data suggest important therapeutic implications for leukemic patients with reduced PU.1 levels. Moreover, we provide first proof, that autoregulation of a transcription factor, PU.1, has a crucial function in vivo. We anticipate that our concept of how autoregulation forms an active chromosomal conformation will impact future research on transcription factor networks regulating stem cell fate.
2011-12-01 | GSE33031 | GEO
Project description:The mechanisms that regulate T cell quiescence are poorly understood. We report that tuberous sclerosis complex 1 (Tsc1) establishes a quiescent program in naïve T cells by controlling cell size, cell cycle entry, and responses to T cell receptor stimulation. Loss of quiescence predisposed Tsc1-deficient T cells to apoptosis that depleted conventional T cells and invariant natural killer T cells. Loss of Tsc1 function dampened in vivo immune responses to bacterial infection. Tsc1-deficient T cells exhibited increased mTORC1 but diminished mTORC2 activities, with mTORC1 activation essential for the disruption of immune homeostasis. Therefore, Tsc1-dependent control of mTOR is crucial in establishing naïve T cell quiescence to facilitate adaptive immune function. Naïve CD4 and CD8 T cells from wild-type and Tsc1-deficient mice (in triplicates each group) were stimulated with or without TCR signaling. RNA was analyzed by microarrays. WT/KO for 0 and 4 hr for CD4 (triplicates), and WT/KO for 0 hr for CD8 (duplicates).
2011-07-11 | E-GEOD-29797 | biostudies-arrayexpress
Project description:The mechanisms that regulate T cell quiescence are poorly understood. We report that tuberous sclerosis complex 1 (Tsc1) establishes a quiescent program in naïve T cells by controlling cell size, cell cycle entry, and responses to T cell receptor stimulation. Loss of quiescence predisposed Tsc1-deficient T cells to apoptosis that depleted conventional T cells and invariant natural killer T cells. Loss of Tsc1 function dampened in vivo immune responses to bacterial infection. Tsc1-deficient T cells exhibited increased mTORC1 but diminished mTORC2 activities, with mTORC1 activation essential for the disruption of immune homeostasis. Therefore, Tsc1-dependent control of mTOR is crucial in establishing naïve T cell quiescence to facilitate adaptive immune function.
2011-07-12 | GSE29797 | GEO
Project description:CTLA4 limits expansion of human cytotoxic CD4+ T cells to prevent B cell apoptosis
| PRJNA718290 | ENA