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Summary Vernalization accelerates flowering after prolonged winter cold. Transcriptional and epigenetic changes are known to be involved in the regulation of the vernalization response. Despite intensive applications of next‐generation sequencing in diverse aspects of plant research, genome‐wide transcriptome and epigenome profiling during the vernalization response has not been conducted. In this work, to our knowledge, we present the first comprehensive analyses of transcriptomic and epigenomic dynamics during the vernalization process inArabidopsis thaliana. Six major clusters of genes exhibiting distinctive features were identified. Temporary changes in histone H3K4me3 levels were observed that likely coordinate photosynthesis and prevent oxidative damage during cold exposure. In addition, vernalization induced a stable accumulation of H3K27me3 over genes encoding many development‐related transcription factors, which resulted in either inhibition of transcription or a bivalent status of the genes. Lastly,FLC‐like andVIN3‐like genes were identified that appear to be novel components of the vernalization pathway.
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Chromatin Organization Governs Transcriptional Response and Plasticity of Cancer Stem Cells
Abstract Chromatin organization regulates transcription to influence cellular plasticity and cell fate. We explored whether chromatin nanoscale packing domains are involved in stemness and response to chemotherapy. Using an optical spectroscopic nanosensing technology we show that ovarian cancer‐derived cancer stem cells (CSCs) display upregulation of nanoscale chromatin packing domains compared to non‐CSCs. Cleavage under targets and tagmentation (CUT&Tag) sequencing with antibodies for repressive H3K27me3 and active H3K4me3 and H3K27ac marks mapped chromatin regions associated with differentially expressed genes. More poised genes marked by both H3K4me3 and H3K27me3 were identified in CSCs vs. non‐CSCs, supporting increased transcriptional plasticity of CSCs. Pathways related to Wnt signaling and cytokine‐cytokine receptor interaction were repressed in non‐CSCs, while retinol metabolism and antioxidant response were activated in CSCs. Comparative transcriptomic analyses showed higher intercellular transcriptional heterogeneity at baseline in CSCs. In response to cisplatin, genes with low baseline expression levels underwent the highest upregulation in CSCs, demonstrating transcriptional plasticity under stress. Epigenome targeting drugs downregulated chromatin packing domains and promoted cellular differentiation. A disruptor of telomeric silencing 1‐like (Dot1L) inhibitor blocked transcriptional plasticity, reversing stemness. These findings support that CSCs harbor upregulated chromatin packing domains, contributing to transcriptional and cell plasticity that epigenome modifiers can target.
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- Award ID(s):
- 1830961
- PAR ID:
- 10576613
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Science
- Volume:
- 12
- Issue:
- 17
- ISSN:
- 2198-3844
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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