• BMB Reports
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• v.33 no.3
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• pp.263-267
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• 2000

We cloned $hda1^+$ (histone deacetylase 1) of fission yeast Schizosaccharomyces pombe. The hda1 of S. pombe was previously reported to encode for an active histone deacetylase (Rundlett et al., 1996; Olsson et al., 1998). The $hda1^+$ is phylogenetically related to the new open reading frame HOS2 of Saccharomyces cerevisiae and only shows a partial homology to the well-known histone deacetylase subclasses, RPD3 and HDA1. A single hda1 mRNA of 1.8 kb was detected at the same level in actively growing and nitrogen-starved cells. When highly over-expressed in S. pombe from an inducible promoter, $hda1^+$ inhibited cell proliferation and caused defects in morphology and cell division. The increased histone deacetylase activity was detected in hdar over-expressing cells. These results suggest that the Hda1p should function on the regulation of cell division possibly by (Allfrey, 1966) direct deacetylation of cytoskeletal (Wade et al., 1997) and cell division regulatory proteins, (Wolffe, 1997) or by controlling their gene expressions.

• BMB Reports
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• v.50 no.4
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• pp.162-163
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• 2017

RNA polymerase II-interacting the Set2 methyltransferase co-transcriptionally methylates histone H3 at lysine 36 within the body of genes. This modification facilitates histone deacetylation by Rpd3S HDAC in 3' transcribed regions to suppress cryptic initiation and slow elongation. Although this pathway is important for global deacetylation, no strong effects have been seen on genome-wide transcription under optimized laboratory conditions. In contrast, this pathway slows the kinetics of mRNA induction when target genes are induced upon environmental changes. Interestingly, a majority of Set2-repressed genes are overlapped by a lncRNA transcription that targets H3K36 methylation and deacetylation by Rpd3S HDAC to mRNA promoters. Furthermore, this pathway delays the induction of many cryptic transcripts upon environmental changes. Therefore, the Set2-Rpd3S HDAC pathway functions to fine-tune expression dynamics of mRNAs and ncRNAs.

• Molecules and Cells
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• v.45 no.9
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• pp.622-630
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• 2022

Colorectal cancer (CRC) has a high mortality rate among cancers worldwide. To reduce this mortality rate, chemotherapy (5-fluorouracil, oxaliplatin, and irinotecan) or targeted therapy (bevacizumab, cetuximab, and panitumumab) has been used to treat CRC. However, due to various side effects and poor responses to CRC treatment, novel therapeutic targets for drug development are needed. In this study, we identified the overexpression of EHMT1 in CRC using RNA sequencing (RNA-seq) data derived from TCGA, and we observed that knocking down EHMT1 expression suppressed cell growth by inducing cell apoptosis in CRC cell lines. In Gene Ontology (GO) term analysis using RNA-seq data, apoptosis-related terms were enriched after EHMT1 knockdown. Moreover, we identified the CHOP gene as a direct target of EHMT1 using a ChIP (chromatin immunoprecipitation) assay with an anti-histone 3 lysine 9 dimethylation (H3K9me2) antibody. Finally, after cotransfection with siEHMT1 and siCHOP, we again confirmed that CHOP-mediated cell apoptosis was induced by EHMT1 knockdown. Our findings reveal that EHMT1 plays a key role in regulating CRC cell apoptosis, suggesting that EHMT1 may be a therapeutic target for the development of cancer inhibitors.

• Journal of Life Science
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• v.25 no.6
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• pp.703-708
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• 2015

Hox genes encode a highly conserved family of homeodomain-containing transcription factors controlling vertebrate pattern formation along the anteroposterior body axis during embryogenesis. Retinoic acid (RA) is a key morphogen in embryogenesis and a critical regulator of both adult and embryonic cellular activity. Specifically, RA regulates Hox gene expression in mouse- or human-derived embryonic carcinoma (EC) cells. Histone modification has been reported to play a pivotal role in the process of RA-induced gene expression and cell differentiation. As histone modification is thought to play an essential role in RA-induced Hox gene expression, we examined RA-induced initiation of collinear expression of Hox genes and the corresponding histone modifications in F9 murine embryonic teratocarcinoma (EC) cells. Hox expression patterns and histone modifications were analyzed by semiquantitative RT-PCR, RNA-sequencing, and chromatin immuno-precipitation (ChIP)-PCR analyses. The Hoxc4 gene (D0) was initiated earlier than the Hoxc5 to –c10 genes (D3) upon RA treatment (day 0 [D0], day 1 [D1], and day 3 [D3]). The Hox nonexpressing D0 sample had a strong repressive marker, H3K27me3, than the D1 and D3 samples. In the D1 and D3 samples, reduced enrichment of the H3K27me3 marker was observed in the whole cluster. The active H3K4me3 marker was closely associated with the collinear expression of Hoxc genes. Thus, the Hoxc4 gene (D1) and all Hoxc genes (D3) expressed H3K4me3 upon transcription activation. In conclusion, these data indicated that removing H3K27me3 and acquiring H3K4me3 regulated RA-induced Hoxc gene collinearity in F9 cells.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.7
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• pp.3605-3610
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• 2016

Background: Histone acetylation in chromatin structures plays a key role in regulation of gene transcription and is strictly controlled by histone acetyltransferase (HAT) and deacetylase (HDAC) activities. HDAC deregulation has been reported in several cancers. Materials and Methods: The expression of 10 HDACs (including HDAC class I and II) was studied by quantitative reverse transcription-PCR (qRT-PCR) in a cohort of mesenchymal stem cells (MM-MSCs) from 10 multiple myeloma patients with a median age 60y. The results were compared with those obtained for normal donors. Then, a coculture system was performed between MM-MSCs and u266 cell line, in the presence or absence of sodium butyrate (NaBT), to understand the effects of HDAC inhibitors (HDACi) in MM-MSCs on multiple myeloma cases. Also, the interleukin-6 (IL-6) and vascular endothelial growth factor (VEGFA) gene expression level and apoptotic effects were investigated in MM-MSCs patients and control group following NaBT treatment. Results: The results indicated that upregulated (HDACs) and downregulated (IL6 and VEGFA) genes were differentially expressed in the MM-MSCs derived from patients with multiple myeloma and ND-MSCs from normal donors. Comparison of the MM-MSCs and ND-MSCs also showed distinct HDACs expression patterns. For the first time to our knowledge, a significant increase of apoptosis was observed in coculture with MM-MSCs treated with NaBT. Conclusions: The obtained findings elucidate a complex set of actions in MSCs in response to HDAC inhibitors, which may be responsible for anticancer effects. Also, the data support the idea that MSCs are new therapeutic targets as a potential effective strategy for MM.

• Parasites, Hosts and Diseases
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• v.62 no.1
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• pp.98-116
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• 2024

Epigenetic writers including DNA and histone lysine methyltransferases (DNMT and HKMT, respectively) play an initiative role in the differentiation and development of eukaryotic organisms through the spatiotemporal regulation of functional gene expressions. However, the epigenetic mechanisms have long been suspected in helminth parasites lacking the major DNA methyltransferases DNMT1 and DNMT3a/3b. Very little information on the evolutionary status of the epigenetic tools and their role in regulating chromosomal genes is currently available in the parasitic trematodes. We previously suggested the probable role of a DNMT2-like protein (CsDNMT2) as a genuine epigenetic writer in a trematode parasite Clonorchis sinensis. Here, we analyzed the phylogeny of HKMT subfamily members in the liver fluke and other platyhelminth species. The platyhelminth genomes examined conserved genes for the most of SET domain-containing HKMT and Disruptor of Telomeric Silencing 1 subfamilies, while some genes were expanded specifically in certain platyhelminth genomes. Related to the high gene dosages for HKMT activities covering differential but somewhat overlapping substrate specificities, variously methylated histones were recognized throughout the tissues/organs of C. sinensis adults. The temporal expressions of genes involved in eggshell formation were gradually decreased to their lowest levels proportionally to aging, whereas those of some epigenetic tool genes were re-boosted in the later adult stages of the parasite. Furthermore, these expression levels were significantly affected by treatment with DNMT and HKMT inhibitors. Our data strongly suggest that methylated histones are potent epigenetic markers that modulate the spatiotemporal expressions of C. sinensis genes, especially those involved in sexual reproduction.

• Proceedings of the KSAR Conference
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• 2004.06a
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• pp.189-189
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• 2004

Histone acetylation as epigenetic marker plays a critical role in gene expression through the interaction of nucleosomes with DNA, modulating the efficiency which RNA-polymerase can interact with promotors to initiate transcription. After fertilization, highly acetylated chromatin takes place and maintain during 1cell stages. The hyperacetylation may lead minor genome activation for survival and cleavage, and then may affect embryonic genome activation and development to balstocyst. (omitted)

• Proceedings of the Korean Society of Toxicology Conference
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• 2003.10b
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• pp.168-168
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• 2003

The acetylation of histone is one of the mechanisms involved in the regulation of gene expression and is tightly controlled by two core enzymes, histone acetyltransferase (HAT) and deacetylase (HDAC). There are several reports that imbalance of HAT and HDAC activity is associated with abnormal behavior of the cells in morphology, cell cycle, differentiation, and carcinogenesis.(omitted)

• Journal of Radiopharmaceuticals and Molecular Probes
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• v.6 no.2
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• pp.165-170
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• 2020

Histone Deacetylases (HDACs) are enzymes that have control gene expression regulation and cell state. In additions, inhibitions of HDACs are associated with growth arrest, differentiation, or apoptosis of tumor cell. Thus HDAC inhibition is one of the interesting biological targets. A variety of HDAC inhibitors has been developed by many scientists, and some of chemical structures related with HDAC inhibitors were modified to give radiolabeled HDAC inhibitors for positron emission tomography (PET) study. In this highlight review, the development of radiolabeled HDAC inhibitors for PET study are described.

• Proceedings of the PSK Conference
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• 2005.11a
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• pp.218-218
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• 2005