Biology subjects

Iwama, A.

Publications and source records attributed to Iwama, A..

16 recordsLinked to original sources

bioRxiv2026

Coffee remodels the global histone acetylation landscape with reduced H3K27ac at the MYC promoter

Coffee consumption has been associated with reduced risks of multiple chronic diseases, including cancer; however, whether coffee regulates the epigenetic landscape remains largely unknown. Here, we show that coffee extensively remodels the histone acetylation landscape in human cells. Quantitative histone modification proteomics revealed a global reduction in active histone acetylation marks following coffee treatment. Mechanistically, coffee reduced the abundance of the histone acetyltransferases GCN5 and MOF, decreased 14-3-3 proteins, promoted the nuclear accumulation of class II histone deacetylases, and induced histone hypoacetylation that was reversed by the histone deacetylase inhibitor trichostatin A. Genome-wide H3K27ac profiling revealed widespread loss of promoter and enhancer acetylation, accompanied by broad transcriptional reprogramming. Integrative analyses of ChIP-seq, RNA-seq, proteomics and biochemical validation consistently demonstrated suppression of the MYC transcriptional program, including reduced MYC expression, decreased H3K27ac at MYC target promoters, downregulation of canonical MYC target genes and attenuation of MYC target gene signatures. Functionally, coffee inhibited cancer cell proliferation with minimal cell death. Collectively, our findings identify whole coffee as a previously unrecognized epigenetic modulator that remodels the histone acetylation landscape in association with suppression of the MYC transcriptional program, providing a molecular framework for understanding the epigenetic basis underlying the anti-tumor effects of coffee.

molecular biology↗

bioRxiv2026

DNA barcoding-based paired daughter cell analysis reveals division preferences of hematopoietic stem cells

Hematopoietic stem cells(HSCs) maintain their pools by stem-stem division and produce mature blood cells through stem-progenitor or progenitor-progenitor division. A paired daughter cell(PDC) assay combined with single cell transplantation is a powerful method to compare the lineage outputs of two HSC daughter cells. However, single-cell transplantation precludes large-scale analysis of daughter-cell pairs, as only one cell can be transplanted per recipient. Here, we developed a DNA barcoding-based PDC assay to overcome this limitation, enabling simultaneous analysis of 476 daughter pairs from individual HSC divisions and revealing that daughter-cell fates are coordinated and that HSC division patterns are biased toward stem-stem and progenitor-progenitor divisions rather than stem-progenitor divisions. These findings indicate that HSC fate outcomes are directed toward symmetric division outcomes. Integration of single-cell RNA sequencing with DNA barcoding revealed a continuum of HSC states--from balanced HSCs to myeloid-biased HSCs and ultimately to a low-output HSC subset--in which progressively reduced production of mature blood cells relative to stem cell expansion, a proxy for stem-stem division bias, exhibits distinct activities of transcription factors and signaling pathways. Overall, our analysis uncovers characteristic patterns of HSC division and links stem maintenance with distinct molecular features.

cell biology↗

bioRxiv2026

BRM preserves sinusoidal niche integrity to prevent microenvironmental senescence and sustain hematopoietic stem cells

During aging and stress, remodeling of the bone marrow (BM) microenvironment compromises hematopoietic stem cell (HSC) maintenance, contributing to an extrinsic HSC aging phenotype. Although niche-derived Notch signaling is essential for hematopoietic regeneration following myelosuppressive injury, the upstream epigenetic mechanisms that regulate this stress-responsive signaling remain poorly understood. Here, we identify the chromatin remodeler BRM (SMARCA2) as a critical regulator of the BM sinusoidal niche that preserves vascular integrity and hematopoietic regeneration. Using reciprocal BM transplantation, we demonstrate that a Brm-deficient microenvironment impairs HSC repopulating capacity and imposes an aging-like myeloid bias characterized by expansion of granulocyte-monocyte progenitors. Following 5-fluorouracil (5-FU)-induced myelosuppression, BrmKO mice exhibit defective sinusoidal regeneration accompanied by endothelial degeneration. Mechanistically, BRM deficiency attenuates endothelial Notch signaling by impairing stress-induced Notch2 expression in sinusoidal endothelial cells (SECs), while simultaneously reducing Jag2 ligand pool through persistent depletion of SECs and impaired stress-induced expansion of Jag2-producing LepR-positive stromal cells. These alterations attenuate endothelial Notch signaling, resulting in defective sinusoidal regeneration, loss of mesenchymal niche support, and progressive displacement of HSCs from the sinusoidal vasculature. Notably, Brm expression is physiologically reduced in aged wild-type SECs and LepR-positive stromal cells. Collectively, our findings identify BRM as a key epigenetic regulator of bone marrow niche integrity and suggest that age-associated BRM decline contributes to niche dysfunction and hematopoietic aging. Key PointsO_LIBRM preserves the bone marrow niche to sustain HSC repopulating capacity and prevent aging-associated myeloid bias. C_LIO_LIBRM preserves stress-responsive Notch signaling in the bone marrow niche, thereby maintaining sinusoidal integrity and HSC localization. C_LI

immunology↗

bioRxiv2026

The lack of macrophage fragment adhesion is a benchmark of dormant hematopoietic stem cells throughout the lifespan

Hematopoietic stem cells (HSCs) play a pivotal role in the lifelong maintenance of hematopoiesis. However, heterogeneity and age-related alterations in HSC populations hinders accurate HSC analysis. Here, we show that bone marrow (BM) macrophage fragments that preferentially express F4/80 adhere to proliferative rather than dormant HSCs. The adhesion of macrophage fragments to proliferative HSCs occurred throughout the process of BM cell preparation in vitro. Consistently, proliferative HSCs express genes involved in the adhesion of macrophage fragments at higher levels than dormant HSCs. Notably, by using that as a benchmark, dormant HSCs can be easily identified as F4/80lowHSCs throughout their lifespan, thereby revealing that they retain considerable stemness and remain functional with aging. Collectively, we propose a novel and straightforward method for the rapid identification, isolation, and analysis of distinct HSC subpopulations, which will be helpful for a wide range of hematological studies and will provide insights into HSC biology. (149 words)

immunology↗

bioRxiv2026

A positional and combinatorial regulatory code for alternative splicing

Alternative pre-mRNA splicing generates extensive transcript diversity, yet the regulatory code that determines how splicing decisions are encoded across the transcriptome remains poorly defined. Splicing outcomes are controlled by combinatorial RNA-binding protein (RBP) interactions and positional context, but how these features are integrated at the transcriptome scale remains unclear. CLIP-based approaches have mapped RBP binding, but directly comparable endogenous maps across multiple RBPs are lacking, limiting inference of global regulatory principles. Here we introduce SCALE-CLIP, an endogenous CLIP framework that integrates CRISPR-Cas9-mediated epitope tagging with long-read-guided read attribution to generate directly comparable RBP binding maps across splicing-regulatory factors. Applied to 23 RBPs, SCALE-CLIP expanded endogenous RBP coverage and, across benchmarked shared factors, increased peak recovery by a median of 12.2-fold relative to ENCODE eCLIP while preserving specificity and reproducibility. We define a transcriptome-wide positional and combinatorial code for alternative splicing, in which binding position is a primary determinant of regulatory outcome: SRSF binding within alternative exons promotes inclusion, whereas binding on flanking exons drives exon skipping. Higher-order SRSF occupancy further tunes this code, buffering exon inclusion when centered on alternative exons but reinforcing repression when distributed across flanking exons. We also show that m6A provides an epitranscriptomic layer that locally enhances SRSF binding and is associated with increased exon inclusion. Together, these results establish a multi-layered RNA-binding logic in which binding position, combinatorial RBP architecture and RNA modification jointly shape splicing outcomes, providing a framework for rational interpretation and modulation of alternative splicing.

molecular biology↗

bioRxiv2025

Niche-targeted therapy via YAP/TAZ activation enhances hematopoietic regeneration

The distinctive milieu of the bone marrow (BM), known as the BM niche, supports hematopoietic stem cells (HSCs) and serves as a foundation for hematopoietic regeneration. Myeloablative stress disrupts not only hematopoietic stem and progenitor cells but also essential BM niche components, including endothelial cells (ECs) and mesenchymal stromal cells (MSCs); disruption of the latter impairs efficient hematopoietic recovery. However, therapeutic strategies targeting niche restoration remain largely underdeveloped. Here, we demonstrate that the Hippo pathway effectors YAP/TAZ are critical for enabling ECs and MSCs to respond to BM injury, and that YAP/TAZ activation accelerates BM niche recovery, thereby promoting hematopoietic regeneration. We found that YAP/TAZ are rapidly activated in both MSCs and ECs following myeloablative stress, maintaining MSC multipotency and orchestrating vascular remodeling. Mechanistically, YAP/TAZ function as transcriptional hubs in MSCs, regulating key transcriptional factors such as Ebf1 and Ebf3. This regulation preserves MSC identity by preventing osteogenic and fibrogenic differentiation while promoting the expression of hematopoietic factors such as Cxcl12 and angiogenic factors. In parallel, YAP/TAZ signaling in ECs facilitates pro-angiogenic responses and drives sinusoidal vessel remodeling after injury. These YAP/TAZ-mediated niche responses are essential for HSC retention and hematopoietic regeneration following diverse myelosuppressive therapies. Notably, pharmacological activation of YAP/TAZ enhances BM niche reorganization and augments hematopoietic regeneration following myeloablative therapies. These findings establish YAP/TAZ as central regulators of BM niche resilience, providing a rationale for niche-targeted therapeutic strategies to enhance hematopoietic regeneration. Key points{blacksquare} YAP/TAZ enable BM niche cells to sense injury and restore their structure and function, thereby promoting hematopoietic regeneration. {blacksquare}Pharmacological activation of YAP/TAZ enhances BM niche resilience and accelerates hematopoietic recovery after myelosuppressive therapies.

cell biology↗

bioRxiv2024

CH-related Mutant ASXL1 Promotes Atherosclerosis in Mice via Dysregulated Innate Immunity

Certain somatic mutations confer a fitness advantage in hematopoietic stem and progenitor cells (HSPCs) over normal HSPCs, resulting in the clonal expansion of mutant blood cells1, otherwise known as clonal haematopoiesis (CH). CH is frequently observed among healthy elderly people and is closely associated with the risk of cardiovascular diseases (CVDs). The most frequently mutated genes of CH include DNMT3A, TET2, and ASXL12. Among them, even though ASXL1 mutations are clinically associated with the highest risk for developing CVDs, little is known whether and how the mutations contribute to CVDs. Here we show accelerated development of atherosclerosis and increased inflammatory monocytes in mice transplanted with the bone marrow cells (BMCs) from the mice expressing mutant ASXL1 (ASXL1-MT) selectively in hematopoietic cells. RNA sequencing analysis of the plaque-macrophages derived from BMCs expressing ASXL1-MT showed more inflammatory signatures than those from control BMCs. Mechanistically, wild-type ASXL1 inhibited innate immune signalling through direct interactions with IRAK1/TRAF6/TAK1 in the cytoplasm, while ASXL1-MT, which only interacted with TAK1, lost this regulatory function, leading to NF-{kappa}B activation. This mechanism is unique and distinct from those of CH with Tet2 or Dnmt3a mutations, where overactivation of the IL-1{beta}/NLRP3 inflammasome plays critical roles3-5. Intriguingly, IRAK1/4 inhibition decreased the number of inflammatory monocytes and attenuated the development of atherosclerosis driven by ASXL1-MT. The present work connects the mutations of an epigenetic factor, ASXL1, with inflammation and CVDs and gives an indication for the prevention of CVDs in CH.

cell biology↗

bioRxiv2024

Structural insights into the agonist selectivity and structure-based engineering of the adenosine A3 receptor

Adenosine receptors, expressed across various tissues, play pivotal roles in physiological processes and are implicated in diverse diseases, including neurological disorders and inflammation, highlighting the therapeutic potential of receptor-selective agents. The Adenosine A3 receptor (A3R), the last identified adenosine receptor, is also activated by breakdown products of post-transcriptionally modified tRNA and exhibits dual roles in neuron, heart, and immune cells, and is often overexpressed in tumors, making it a target for anticancer therapy. Despite extensive studies on the other adenosine receptors, the structure and activation mechanism of A3R, especially by selective agonists like N6-methyladenosine (m6A) and namodenoson, remained elusive. Here, we identified N6-isopentenyl adenosine (i6A), a novel A3R-selective ligand, via comprehensive modified adenosine library screening. Cryo-EM analyses of A3R-Gi signaling complexes with two nonselective and three selective agonists revealed the structural basis for A3R activation. We further conducted structure-guided engineering of m6A-insensitive A3R, which would greatly facilitate future discoveries of the physiological functions of the selective activation of A3R by modified adenosines. Our results clarify the selective activation of adenosine receptors, providing the basis for future drug discovery.

biophysics↗

bioRxiv2023

Structure and dynamics of the RF-amide QRFP receptor GPR103

Pyroglutamylated RF amide peptide (QRFP) is a type of peptide hormone with a C-terminal RF-amide motif. QRFP selectively activates class-A categorized GPCR, GPR103 to exert various physiological functions such as energy metabolism and appetite regulation. Here, we report the cryo-electron microscopy structure of the QRFP-GPR103-Gq complex at 3.3 [A] resolution. Unlike class-A GPCR, QRFP adopts an extended structure baring no secondary structure, with its N-terminal and C-terminal sides recognized by extracellular and transmembrane domains, respectively, of GPR103. The C-terminal heptapeptide of QRFP penetrates into the orthosteric pocket to act in receptor activation. Particularly, the residues that recognize the RF-amide are highly conserved in the RF-amide receptors. Notably, the unique N-terminal helix-loop-helix of the receptor traps the N-terminal side of QRFP with the pendulum-like motion to guide QRFP into the ligand-binding pocket. This movement, reminiscent of class B1 GPCRs except for orientation and structure of the ligand, is critical for the high affinity binding and receptor specificity of QRFP. Structural comparisons with closely related receptors, including RY-amide peptide-recognizing GPCRs, revealed conserved and diversified peptide recognition mechanisms, providing profound insights into the biological significance of RF-amide peptides. This study not only advances our understanding of GPCR-ligand interactions, but also paves the way for the development of novel therapeutics targeting metabolic and appetite disorders and emergency medical care.

biochemistry↗

bioRxiv2023

Optimizing Cryo-EM Structural Analysis of Gi-coupling Receptors via Engineered Gt and Nb35 Application

Cryo-EM single particle analysis has recently facilitated the high-resolution structural determination of numerous GPCR-G complexes. Diverse methodologies have been devised with this trend, and in the case of GPCR-Gi complexes, scFv16, an antibody that recognizes the intricate interface of the complex, has been mainly implemented to stabilize the complex. However, owing to their flexibility and heterogeneity, structural determinations of GPCR-Gi complexes remain both challenging and resource-intensive. By employing eGt, which exhibits binding affinity to modified nanobody Nb35, the cryo-EM structure of Rhodopsin-eGt complex was previously reported. Using this modified G protein, we determined the structure of the ETB-eGt complex bound to the modified Nb35. The determined structure of ETB receptor was the same as the previously reported ETB-Gi complex, and the resulting dataset demonstrated significantly improved anisotropy. This modified G protein will be utilized for the structural determination of other GPCR-Gi complexes. HighlightsO_LIThe study introduces the engineered G protein subunit eGT, which enhances the resolution of GPCR-G protein structures by suppressing G protein conformational fluctuations and is particularly beneficial for Gi-coupled receptors. C_LIO_LIThe cryo-EM structure of the ETB receptor complexed with eGt-Nb35 reveals improved map quality, reduced anisotropy, and isotropic density distribution, increasing the accuracy of structural analysis. C_LIO_LIStructural comparison between ETB-Gi and ETB-eGt reveals similar receptor-G protein interactions, demonstrating the utility of eGt-Nb35 for studying GPCR-Gi complexes and the potential for broader applications within the Gi family. C_LI

bioengineering↗

bioRxiv2023

Context-Dependent Modification of PFKFB3 in Hematopoietic Stem Cells Promotes Anaerobic Glycolysis and Ensures Stress Hematopoiesis

Metabolic pathways are plastic and rapidly change in response to stress or perturbation. Current metabolic profiling techniques require lysis of many cells, complicating the tracking of metabolic changes over time after stress in rare cells such as hematopoietic stem cells (HSCs). Here, we aimed to identify the key metabolic enzymes that define differences in glycolytic metabolism between steady-state and stress conditions in HSCs and elucidate their regulatory mechanisms. Through quantitative 13C metabolic flux analysis of glucose metabolism using high-sensitivity glucose tracing and mathematical modeling, we found that HSCs activate the glycolytic rate-limiting enzyme phosphofructokinase (PFK) during proliferation and oxidative phosphorylation (OXPHOS) inhibition. Real-time measurement of adenosine triphosphate (ATP) levels in single HSCs demonstrated that proliferative stress or OXPHOS inhibition led to accelerated glycolysis via increased activity of PFKFB3, the enzyme regulating an allosteric PFK activator, within seconds to meet ATP requirements. Furthermore, varying stresses differentially activated PFKFB3 via PRMT1-dependent methylation during proliferative stress and via AMPK-dependent phosphorylation during OXPHOS inhibition. Overexpression of Pfkfb3 induced HSC proliferation and promoted differentiated cell production, whereas inhibition or loss of Pfkfb3 suppressed them. This study reveals the flexible and multilayered regulation of HSC glycolytic metabolism to sustain hematopoiesis under stress and provides techniques to better understand the physiological metabolism of rare hematopoietic cells. Key PointsO_LICombined isotope tracing, mathematical modeling, and single cell ATP analysis enable high-resolution evaluation of blood cell metabolism. C_LIO_LIUnder stress, HSCs quickly accelerate glycolysis to meet ATP demands and maintain hematopoiesis via context-dependent PFKFB3 activation. C_LI

cell biology↗

bioRxiv2022

Sox17 downstream gene Rasip1 is involved in the hematopoietic activity of intra-aortic hematopoietic clusters in the midgestation mouse embryo

BackgroundDuring mouse embryonic development, definitive hematopoiesis is first detected around embryonic day (E) 10.5 in the aorta-gonad-mesonephros (AGM) region. Hematopoietic stem cells (HSCs) arise in the dorsal aortas intra-aortic hematopoietic cell clusters (IAHCs). We have previously reported that a transcription factor Sox17, is expressed in IAHCs, and that, among them, CD45lowc-Kithigh cells have high hematopoietic activity. Furthermore, forced expression of Sox17 in this population of cells can maintain the formation of hematopoietic cell clusters. However, how Sox17 does so, particularly downstream signaling involved, remains poorly understood. The purpose of this study is to search for new Sox17 targets which contribute to cluster formation with hematopoietic activity. MethodsRNA-sequencing (RNA-seq) analysis was done to identify genes that are up- regulated in Sox17-expressing IAHCs as compared with Sox17-negative ones. Among the top 7 highly expressed genes, Rasip1 which had been reported to be a vascular-specific regulator was focused on in this study and firstly the whole-mount immunostaining was done. We conducted a luciferase reporter assay to identify the Sox17 binding site for Rasip1 gene induction. We also analyzed the cluster formation and the multi-lineage colony forming ability of Rasip1-transduced cells and Rasip1-knockdown Sox17-transduced cells. ResultsThe increase of the Rasip1 expression level was observed in Sox17-positive CD45lowc-Kithigh cells as compared with the Sox17-nonexpressing control. Also, the expression level of the Rasip1 gene was increased by the Sox17-nuclear translocation. Rasip1 was expressed on the membrane of IAHCs, overlapping with the endothelial cell marker, CD31, and hematopoietic stem/progenitor marker (HSPC), c-Kit. Overexpression of Rasip1 in CD45lowc-Kithigh cells led to a significant but transient increase in hematopoietic activity, while Rasip1 knock-down in Sox17-transduced cells decreased the cluster formation and diminished the colony-forming ability. ConclusionsRasip1 knockdown in Sox17-transduced CD45lowc-Kithigh cells displayed a significant decrease in the multi-lineage colony forming ability and the cluster size. Rasip1 overexpression in Sox17-untransduced CD45lowc-Kithigh cells led to a significant but transient increase in the multi-lineage colony forming ability, suggesting the presence of a cooperating factor for sustained hematopoietic activity.

developmental biology↗

bioRxiv2022

Polycomb repressive complex 1.1 coordinates homeostatic and emergency myelopoiesis

Polycomb repressive complex (PRC) 1 regulates stem cell fate by mediating mono-ubiquitination of histone H2A at lysine 119. While canonical PRC1 is critical for hematopoietic stem and progenitor cell (HSPC) maintenance, the role of non-canonical PRC1 in hematopoiesis remains elusive. PRC1.1, a non-canonical PRC1, consists of PCGF1, RING1B, KDM2B, and BCOR. We recently showed that PRC1.1 insufficiency induced by the loss of PCGF1 or BCOR causes myeloid-biased hematopoiesis and promotes transformation of hematopoietic cells in mice. Here we show that PRC1.1 serves as an epigenetic switch that coordinates homeostatic and emergency hematopoiesis. PRC1.1 maintains balanced output of steady-state hematopoiesis by restricting C/EBP-dependent precocious myeloid differentiation of HSPCs and the HOXA9- and {beta}-catenin-driven self-renewing network in myeloid progenitors. Upon regeneration, PRC1.1 is transiently inhibited to facilitate formation of granulocyte-macrophage progenitor (GMP) clusters, thereby promoting emergency myelopoiesis. Moreover, constitutive inactivation of PRC1.1 results in unchecked expansion of GMPs and eventual transformation. Collectively, our results define PRC1.1 as a novel critical regulator of emergency myelopoiesis, dysregulation of which leads to myeloid transformation.

immunology↗

bioRxiv2022

Single-cell multi-omics analyses reveal EZH2 as a main driver of retinoic acid resistance in PLZF-RARA leukemia.

Cancer relapse is caused by a subset of malignant cells that are resistant to treatment. To characterize resistant cells and their vulnerabilities, we studied the retinoic acid (RA)-resistant PLZF-RARA acute promyelocytic leukemia (APL) using single-cell multi-omics. We uncovered transcriptional and chromatin heterogeneity in leukemia cells and identified a subset of cells resistant to RA that depend on a fine-tuned transcriptional network targeting the epigenetic regulator Enhancer of Zeste Homolog 2 (EZH2). Epigenomic and functional analyses validated EZH2 selective dependency of PLZF-RARA leukemia and its driver role in RA resistance. Targeting pan-EZH2 activities (canonical/non-canonical) was necessary to eliminate leukemia relapse initiating cells, which underlies a dependency of resistant cells on an EZH2 non-canonical activity and the necessity to degrade EZH2 to overcome resistance. Our study provides critical insights into the mechanisms of RA resistance that allow us to eliminate treatment-resistant leukemia cells by targeting EZH2, thus highlighting a potential targeted therapy approach. HIGHLIGHTS- sc-RNAseq identifies PLZF-RARA leukemia heterogeneity and retinoic acid resistant cells - sc-ATACseq refines leukemic cell identity and resolves retinoic acid resistant networks - EZH2 is a selective dependency of PLZF-RARA leukemia and drives retinoic acid resistance - Targeting pan-EZH2 activities (canonical/non-canonical) is necessary to overcome leukemia onset

cancer biology↗

bioRxiv2021

Stem cell therapy for skin regeneration using mesenchymal stem cells derived from the progeroid Werner syndrome-specific iPS cells

Adult progeria, Werner syndrome (WS), is an autosomal recessive disorder that develops accelerated aging-associated symptoms after puberty. Refractory skin ulcer of limbs, which is one of the symptoms specific to WS, is seriously painful and sometimes results in amputation. In recent years, cell therapy using mesenchymal stem cells (MSCs) has been attracting attention; however, the effect of WS-derived MSCs on skin ulcers is still unclear. In this study, we generated iPS cells from a patient with WS and a normal subject, differentiated them into MSCs (WS- and NM-iMSC, respectively), and performed cell therapy to a refractory skin ulcer mouse model. As a result, WS-iMSC recapitulated premature senescence phenotypes in vitro. Upon subcutaneous injection around the wounds of mice, WS-iMSC was significantly inferior in wound healing effect compared to NM-iMSC. Proteome and transcriptome analysis revealed altered expression of genes related to angiogenesis, inflammation, and proliferation in WS-iMSC with remarkable downregulation of VEGF, a potent angiogenic factor. In addition, simultaneous administration of recombinant human VEGF and WS-iMSC improved the wound healing effect in vivo. These results indicate that the expression of angiogenic factors is reduced in WS-iMSC, and its supplementation restores the wound healing ability. This finding may pave the way to develop the treatment of intractable skin ulcers of WS.

cell biology↗

bioRxiv2018

PLZF limits enhancer activity during hematopoietic progenitor aging

PLZF (promyelocytic leukemia zinc finger) is a transcription factor acting as a global regulator of hematopoietic commitment. PLZF displays an epigenetic specificity by recruiting chromatin-modifying factors but little is known about its role in remodeling chromatin of cells committed towards a given specific hematopoietic lineage. In murine myeloid progenitors, we decipher a new role for PLZF in restraining active genes and enhancers by targeting acetylated lysine 27 of Histone H3 (H3K27ac). Functional analyses reveal that active enhancers bound by PLZF are involved in biological processes related to metabolism and associated with hematopoietic aging. Comparing the epigenome of young and old myeloid progenitors, we reveal that H3K27ac variation at active enhancers is a hallmark of hematopoietic aging. Taken together, these data suggest that PLZF, associated with active enhancers, appears to restrain their activity as an epigenetic gatekeeper of hematopoietic aging.

molecular biology↗