Project description:To investigate the effect of the interaction between the MRG1/2 and PIF4, here we analysed differentially expressed genes compared to the mutant and wild-type by RNA-seq under different temperature. We performed gene expression profiling analysis using data obtained from RNA-seq of WT, mrg1 mrg2, pif4, and mrg1 mrg2 pif4 plants at 22degC and 28degC.
Project description:We determined the transcriptomes of hda9-1, pif4-2 and wild type Col-0 seedlings of 2 day old and 7 day old, at control and high temperature conditions (22oC vs 27oC), in short day (8h) photoperiod
Project description:Anchoring of a chromatin remodeler complex by long non-coding RNAs (lncRNAs) is a frequently utilized mechanism for lncRNAs to regulate gene expression. Hypoxia is a microenvironemntal condition that plays a crucial role in promoting tumor progression. We previously identified a hypoxia-inducible lncRNA, RP11-390F4.3, that regulates epithelial–mesenchymal transition (EMT) without a delineated mechanism. Here we show that the lncRNA RP11-390F4.3 (renamed MAHAC: MAintenance of Histone ACetylation) specifically induces histone H4 lysine 5 acetylation (H4K5ac) mark and promotes the enrichment of H4K5ac mark on the promoters of EMT transcription factors. MAHAC scaffolds the ILF3/NF90–ILF2–CBP complex, which is co-localized with the members of the complex inside nucleus under hypoxia. The minimal MAHAC region (nt 686–741) required for scaffolding the complex was mapped and it induces allosteric activation of H4K5ac in in vitro histone acetyltransferase assay. This minimal MAHAC region is essential for hypoxia-induced EMT, migration, invasion, and H4K5ac activation. These findings demonstrate that hypoxia-induced MAHAC represents an unexplored allosteric regulator of H4K5ac that activates EMT and induces tumor progression.
Project description:To investigate the influence of the AtChz1A/B and ARP6 in H2A.Z incorporation, we analysed genome-wide H2A.Z density in the mutant and wild-type by ChIP-seq. We then performed H2A.Z occupancy analysis using data obtained from ChIP-seq of 3 different plants including mutants and wild-type.
Project description:Both genetic and environmental factors are implicated in Type 1 Diabetes (T1D). Since environmental factors can trigger epigenetic changes, we hypothesized that variations in histone posttranslational modifications (PTMs) at the promoter/enhancer regions of T1D susceptible genes may be associated with T1D. We therefore evaluated histone PTM variations at known T1D susceptible genes in blood cells from T1D patients versus healthy non-diabetic controls, and explored their connections to T1D. We used the chromatin-immunoprecipitation-linked-to-microarray approach to profile key histone PTMs, including H3-lysine-4 trimethylation (H3K4me3), H3K27me3, H3K9me3, H3K9 acetylation (H3K9Ac) and H4K16Ac at genes within the T1D susceptible loci in lymphocytes, and H3K4me3, H3K9me2, H3K9Ac and H4K16Ac at the IDDM1 region in monocytes of T1D patients and healthy controls separately. We screened for potential variations in histone PTMs using computational methods to compare datasets from T1D and controls. Interestingly, we observed marked variations in H3K9Ac levels at the upstream regions of HLA-DRB1 and HLA-DQB1 within the IDDM1 locus in T1D monocytes relative to controls. Additional experiments with THP-1 monocytes demonstrated increased expression of HLA-DRB1 and HLA-DQB1 in response to interferon- and TNF-treatment that were accompanied by changes in H3K9Ac at the same promoter regions as that seen in the patient monocytes. These results suggest that the H3K9Ac status of HLA-DRB1 and HLA-DQB1, two genes highly associated with T1D, may be relevant to their regulation and transcriptional response towards external stimuli. Thus, the promoter/enhancer architecture and chromatin status of key susceptible loci could be important determinants in their functional association to T1D susceptibility.
Project description:Dark-grown seedlings exhibit skotomorphogenic development. Genetic and molecular evidence indicates that a quartet of Arabidopsis Phytochrome (phy)-Interacting bHLH Factors (PIF4, 3, 4 and 5) are critically necessary to maintaining this developmental state, and that light activation of phy induces a switch to photomorphogenic development by inducing rapid degradation of the PIFs. Here, using combined ChIP-seq and RNA-seq analyses, we have identified genes that are direct targets of PIF4 transcriptional regulation, and we provide evidence that the quartet collectively regulate these genes by shared, direct binding to the target promoters in promoting skotomorphogenesis. Three biological replicates data of PIF4-binding sites were collected by comparing the parallel ChIP samples from Myc-epitope-tagged-PIF4 (P1M) overexpressing transgenic seedlings and the wild-type (WT) control.
Project description:Anchoring of a chromatin remodeler complex by long non-coding RNAs (lncRNAs) is a frequently utilized mechanism for lncRNAs to regulate gene expression. Hypoxia is a microenvironemntal condition that plays a crucial role in promoting tumor progression. We previously identified a hypoxia-inducible lncRNA, RP11-390F4.3, that regulates epithelial–mesenchymal transition (EMT) without a delineated mechanism. Here we show that the lncRNA RP11-390F4.3 (renamed MAHAC: MAintenance of Histone ACetylation) specifically induces histone H4 lysine 5 acetylation (H4K5ac) mark and promotes the enrichment of H4K5ac mark on the promoters of EMT transcription factors. MAHAC scaffolds the ILF3/NF90–ILF2–CBP complex, which is co-localized with the members of the complex inside nucleus under hypoxia. The minimal MAHAC region (nt 686–741) required for scaffolding the complex was mapped and it induces allosteric activation of H4K5ac in in vitro histone acetyltransferase assay. This minimal MAHAC region is essential for hypoxia-induced EMT, migration, invasion, and H4K5ac activation. These findings demonstrate that hypoxia-induced MAHAC represents an unexplored allosteric regulator of H4K5ac that activates EMT and induces tumor progression.
Project description:In plants, an elevation in ambient temperature induces morphological changes including elongation hypocotyls, considered to be adaptive responses to alleviate the heat-induced damages. The high temperature-induced morphological changes are called thermomorphogenesis, which is predominantly regulated by a bHLH transcription factor PIF4. Although PIF4 is expressed in all aerial tissues including the epidermis, mesophyll, and vascular bundle, its tissue-specific functions in thermomorphogenesis are not known. Here, we found that epidermis-specific expression of PIF4 induced constitutive long hypocotyls, while vasculature-specific expression of PIF4 had no effect on hypocotyl growth. Consistently, RNA-Seq and qRT-PCR analyses revealed that auxin responsive genes and growth-related genes were highly activated by epidermal, but not by vascular, PIF4. The epidermal, but not vascular, inactivation of PIF4 by a PIF4 artificial microRNA or a dominant negative form of PIF4 suppressed thermoresponsive gene expression and hypocotyl growth. Additionally, both the block of epidermal auxin signaling and the epidermal overexpression of a thermosensor phytochrome B (phyB) inhibited thermoresponsive growth, indicating that epidermal PIF4-auxin pathway are essential for the temperature responses. We further show that epidermal PIF4 is increased by high temperatures mainly through the transcriptional activation of PIF4. Taken together, our study demonstrates that the epidermis regulates thermoresponsive growth through the phyB-PIF4-auxin pathway.