Browsing by Subject "Chromatin accessibility"

Now showing 1 - 4 of 4
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    Arid3b Is Critical for B Lymphocyte Development
    (Plos, 2016-08-18) Kurkewich, Jeffrey L.; Klopfenstein, Nathan; Hallas, William M.; Wood, Christian; Sattler, Rachel A.; Das, Chhaya; Tucker, Haley; Dahl, Richard; Dahl, Karen D. Cowden; Department of Biochemistry & Molecular Biology, IU School of Medicine
    Arid3a and Arid3b belong to a subfamily of ARID (AT-rich interaction domain) transcription factors. The Arid family is involved in regulating chromatin accessibility, proliferation, and differentiation. Arid3a and Arid3b are closely related and share a unique REKLES domain that mediates their homo- and hetero-multimerization. Arid3a was originally isolated as a B cell transcription factor binding to the AT rich matrix attachment regions (MARS) of the immunoglobulin heavy chain intronic enhancer. Deletion of Arid3a results in a highly penetrant embryonic lethality with severe defects in erythropoiesis and hematopoietic stem cells (HSCs). The few surviving Arid3a-/- (<1%) animals have decreased HSCs and early progenitors in the bone marrow, but all mature lineages are normally represented in the bone marrow and periphery except for B cells. Arid3b-/- animals die around E7.5 precluding examination of hematopoietic development. So it is unclear whether the phenotype of Arid3a loss on hematopoiesis is dependent or independent of Arid3b. In this study we circumvented this limitation by also examining hematopoiesis in mice with a conditional allele of Arid3b. Bone marrow lacking Arid3b shows decreased common lymphoid progenitors (CLPs) and downstream B cell populations while the T cell and myeloid lineages are unchanged, reminiscent of the adult hematopoietic defect in Arid3a mice. Unlike Arid3a-/- mice, HSC populations are unperturbed in Arid3b-/- mice. This study demonstrates that HSC development is independent of Arid3b, whereas B cell development requires both Arid3a and Arid3b transcription factors.
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    Dynamic chromatin accessibility and transcriptome changes following PDGF-BB treatment of bone-marrow derived mesenchymal stem cells
    (Springer Nature, 2024-10-15) Liu, Sheng; Chu, Xiaona; Reiter, Jill L.; Yu, Xuhong; Fang, Fang; McGuire, Patrick; Gao, Hongyu; Liu, Yunlong; Wan, Jun; Wang, Yue; Medical and Molecular Genetics, School of Medicine
    Background: Mesenchymal stem cells (MSCs) are multipotent stem cells that are under investigation for use in clinical trials because they are capable of self-renewal and differentiating into different cell types under defined conditions. Nonetheless, the therapeutic effects of MSCs have been constrained by low engraftment rates, cell fusion, and cell survival. Various strategies have been explored to improve the therapeutic efficacy of MSCs, with platelet-derived growth factor (PDGF)-BB emerging as a promising candidate. To enhance our comprehension of the impact of PDGF-BB on the gene expression profile and chromosomal accessibility of MSCs, RNA-sequencing and analysis of chromatin accessibility profiles were conducted on three human primary MSCs in culture, both with and without stimulation by PDGF-BB. Results: Integrative analysis of gene expression and chromatin accessibility demonstrated that PDGF-BB treatment modified the chromatin accessibility landscape, marking regions for activation or repression through the AP-1 family transcription factors TEAD, CEBP, and RUNX2. These changes in AP-1 transcription factor expression, in turn, led to cell proliferation and differentiation potential towards osteoblasts, adipocytes, or chondrocytes. The degree of MSC differentiation varies among cells isolated from different donors. The presence of an enrichment of exosome-related genes is also noted among all the differentially expressed genes. Conclusions: In conclusion, the observed changes in AP-1 transcription factor expression not only induced cellular proliferation and differentiation, but also revealed variations in the degree of MSC differentiation based on donor-specific differences. Moreover, the enrichment of exosome-related genes among differentially expressed genes suggests a potential significant role for PDGF-BB in facilitating intercellular communication.
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    Integrated Single-Cell Multiomic Profiling of Caudate Nucleus Suggests Key Mechanisms in Alcohol Use Disorder
    (bioRxiv, 2024-08-06) Green, Nick; Gao, Hongyu; Chu, Xiaona; Yuan, Quiyue; McGuire, Patrick; Lai, Dongbing; Jiang, Guanglong; Xuei, Xiaoling; Reiter, Jill; Stevens, Julia; Sutherland, Greg; Goate, Alison; Pang, Zhiping; Slesinger, Paul; Hart, Ronald P.; Tischfield, Jay A.; Agrawal, Arpana; Wang, Yue; Duren, Zhana; Edenberg, Howard J.; Liu, Yunlong; Medical and Molecular Genetics, School of Medicine
    Alcohol use disorder (AUD) is likely associated with complex transcriptional alterations in addiction-relevant brain regions. We characterize AUD-associated differences in cell type-specific gene expression and chromatin accessibility in the caudate nucleus by conducting a single-nucleus RNA-seq assay and a single-nucleus RNA-seq + ATAC-seq (multiome) assay on caudate tissue from 143 human postmortem brains (74 with AUD). We identified 17 cell types. AUD was associated with a higher proportion of microglia in an activated state and more astrocytes in a reactive state. There was widespread evidence for differentially expressed genes across cell types with the most identified in oligodendrocytes and astrocytes, including genes involved in immune response and synaptic regulation, many of which appeared to be regulated in part by JUND and OLIG2. Microglia-astrocyte communication via interleukin-1 beta, and microglia-astrocyte-oligodendrocyte interaction via transforming growth factor beta 1 were increased in individuals with AUD. Expression quantitative trait loci analysis revealed potential driver genes of AUD, including ADAL, that may protect against AUD in medium spiny neurons and interneurons. This work provides a thorough profile of the effects of AUD in the human brain and identifies several promising genes for further study.
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    PRMT1 promotes pancreatic cancer development and resistance to chemotherapy
    (Elsevier, 2024) Ku, Bomin; Eisenbarth, David; Baek, Seonguk; Jeong, Tae-Keun; Kang, Ju-Gyeong; Hwang, Daehee; Noh, Myung-Giun; Choi, Chan; Choi, Sungwoo; Seol, Taejun; Kim, Yun-Hee; Woo, Sang Myung; Kong, Sun-Young; Lim, Dae-Sik; Medicine, School of Medicine
    Pancreatic ductal adenocarcinoma (PDAC) remains one of the most lethal types of cancer, and novel treatment regimens are direly needed. Epigenetic regulation contributes to the development of various cancer types, but its role in the development of and potential as a therapeutic target for PDAC remains underexplored. Here, we show that PRMT1 is highly expressed in murine and human pancreatic cancer and is essential for cancer cell proliferation and tumorigenesis. Deletion of PRMT1 delays pancreatic cancer development in a KRAS-dependent mouse model, and multi-omics analyses reveal that PRMT1 depletion leads to global changes in chromatin accessibility and transcription, resulting in reduced glycolysis and a decrease in tumorigenic capacity. Pharmacological inhibition of PRMT1 in combination with gemcitabine has a synergistic effect on pancreatic tumor growth in vitro and in vivo. Collectively, our findings implicate PRMT1 as a key regulator of pancreatic cancer development and a promising target for combination therapy.