• Title/Summary/Keyword: Epigenetic change

Search Result 37, Processing Time 0.023 seconds

Enhancing in vitro Grown and Propagation of Bulbs for Cryopreservation in Lily Genetic Resources

  • Jae-young Song;Jung-yoon Yi;Mun-sup Yoon;Jung-ro Lee;Young-yi Lee
    • Proceedings of the Plant Resources Society of Korea Conference
    • /
    • 2020.08a
    • /
    • pp.43-43
    • /
    • 2020
  • Plants regenerated from in vitro cultures are associated with chromosomal variations, which have been generally found in long-term culture. Reducing plant culture age is one of the ways to reduce genetic and epigenetic changes. The present study focused on the efficient in vitro propagation of lily cultivars and has intensified to speed up bulb propagation for cryopreservation. The multiplication process applied in this experiment uses starting material, which the newly small bulb formed from bulb-scales in two lily cultivars. The adventitious bulb from bulb-scale tissue cultured on three different media following Murashige and Skoog (MS) basal medium supplemented with 1 g/L Charcoal, MS medium containing 0.3 mg/L IAA and 0.4 mg/L BA hormone with or without Charcoal, respectively. After about seven weeks, there is little change in the number of newly propagated bulbs in small bulbs of the two media. Compared to the both mediums, the number of the propagated bulbs is increased 5 times in MS medium containing 0.3 mg/L IAA and 0.4 mg/L BA hormone without Charcoal. After about seven weeks, the results of the propagation showed that the number of the propagated bulbs is increased 5 times in MS medium containing 0.3 mg/L IAA and 0.4 mg/L BA hormone without Charcoal compared to the both mediums. The number of propagated bulbs ranged from 5 to 6 and 4 to 6 with an average of 5 in Tropicalpink and Greenstar cultivars, respectively. There is little change in the number of newly propagated bulbs in small bulbs of other media. The multiplication process applied in this study may save in vitro culture period and effort.

  • PDF

DNA methyltransferase 3a is Correlated with Transgene Expression in Transgenic Quails

  • Jang, Hyun-Jun;Kim, Young-Min;Rengaraj, Deivendran;Shin, Young-Soo;Han, Jae-Yong
    • Journal of Animal Science and Technology
    • /
    • v.53 no.3
    • /
    • pp.269-274
    • /
    • 2011
  • DNA methyltransferases (DNMTs) are closely associated with the epigenetic change and the gene silencing through the regulation of methylation status in animal genome. But, the role of DNMTs in transgene silencing has remained unclear. So, we examined whether the knockdown of DNMT influences the reactivation of transgene expression in the transgenic quails. In this study, we investigated the expression of DNMT3a, and DNMT3b in blastoderm, quail embryonic fibroblasts (QEFs) and limited embryonic tissues such as gonad, kidney, heart and liver of E6 transgenic quails (TQ2) by RT-PCR. We further analyzed the expression of DNMT3a at different stages of whole embryos during early embryonic development by qRT-PCR. DNMT3a expression was detected in all test samples; however, it showed the highest expression in E6 whole embryo. Embryonic fibroblasts collected from TQ2 quails were treated with two DNMT3a-targeted siRNAs (siDNMT3a-51 and siDNMT3a-88) for RNA interference assay, and changes in expression were then analyzed by qRT-PCR. The siDNMT3a-51 and siDNMT3a-88 reduced 53.34% and 64.64% of DNMT3a expression in TQ2 QEFs, respectively. Subsequently the treatment of each siRNA reactivated enhanced green fluorescent protein (EGFP) expression in TQ2 (224% and 114%). Our results might provide a clue for understanding the DNA methylation mechanism responsible for transgenic animal production and stable transgene expression.

Expression of Sodium/iodide Symporter Transgene in Neural Stem Cells (신경줄기세포(HB1.F3)에서 나트륨옥소 공동수송체 도입유전자 발현)

  • Kim, Yun-Hui;Lee, Dong-Soo;Kang, Joo-Hyun;Lee, Yong-Jin;Chung, June-Key;Lee, Myung-Chul
    • The Korean Journal of Nuclear Medicine
    • /
    • v.38 no.1
    • /
    • pp.99-108
    • /
    • 2004
  • Purpose: The ability to noninvasively track the migration of neural progenitor cells would have significant clinical and research implications. We generated stably transfected F3 human neural progenitor cells with human sodium/iodide symporter (hNIS) for noninvasively tracking F3. In this study, the expression patterns of hNIS gene in F3-NIS were examined according to the cultured time and the epigenetic modulation. Materials and Methods: F3 human neural stem cells had been obtained from Dr. Seung U. Kim (Ajou University, Suwon, Korea). hNIS and hygromycin resistance gene were linked with IRES (Internal Ribosome Entry Site) under control of CMV promoter. This construct was transfected to F3 with Liposome. To investigate the restoration of hNIS gene expression in F3-NIS, cells were treated with demethylating agent (5-Azacytidine) and Histone deacetylase inhibitor (Trichostatin A: TSA). The expression of hNIS was measured by I-125 uptake assay and RT-PCR analysis. Results: The iodide uptake of the F3-NIS was higher 12.86 times than F3 cell line. According to the cell passage number, hNIS expression in F3-NIS gradually diminished. After treatment of 5-Azacytidine and TSA with serial doses (up to $20{\mu}M$, up to 62.5nM, respectively) for 24 hours, I-125 uptake and mRNA of hNIS in F3-NIS were increased. Conclusion: These results suggest that hNIS transfected F3 might undergo a change in its biological characters by cell passage. Therefore, the gene ex[ressopm of exogenous gene transferred human stem cell might be affected to the epigenetic modulation such as promoter methylation and Histone deacetylation and to the cell culture conditions.

Polymorphisms and Functional Analysis of the Intact Human Papillomavirus16 E2 Gene

  • Ekalaksananan, Tipaya;Jungpol, Watcharapol;Prasitthimay, Chuthamas;Wongjampa, Weerayut;Kongyingyoes, Bunkerd;Pientong, Chamsai
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.15 no.23
    • /
    • pp.10255-10262
    • /
    • 2015
  • High risk human papillomavirus (HR-HPV) E2 proteins play roles in transcriptional regulation and are commonly functionally disrupted when the HPV genome integrates into host chromosomes. Some 15-40% of cancer cases, however, contain an intact E2 gene or episomal HPV. In these cases, polymorphism of the E2 gene might be involved. This study aimed to determine polymorphisms of the E2 gene in episomal HPV16 detected in high grade squamous intraepithelial lesions and squamous cell carcinomas and altered functions compared to the E2 prototype. The E2 gene was amplified and sequenced. Two expression vectors containing E2 gene polymorphisms were constructed and transfected in SiHa and C33A cells, then E6 gene as well as Il-10 and TNF-${\alpha}$ expression was determined by quantitative RT-PCR. Expression vectors and reporter vectors containing the HPV16 long control region (LCR) were co-transfected and transcriptional activity was determined. The results showed that a total of 32 nucleotides and 23 amino acids were changed in all 20 cases of study, found in the transactivation (TA) domain, hinge (H) region and DNA binding (DB) domain with 14, 5 and 13 nucleotide positions. They mostly caused amino acid change. The expressing vectors containing different E2 gene polymorphisms showed E6 mRNA suppression, TNF-${\alpha}$ mRNA suppression and IL-10 induction but no statistically significant differences when compared to the E2 prototype. Moreover, promoter activity in HPV16 LCR was not affected by E2 protein with different gene polymorphisms, in contrast to nucleotide variations in LCR that showed an effect on transcription activity. These results demonstrated that E2 gene polymorphisms of episomal HPV16 did not affect transcriptional regulation and suggested that nucleotide variation as well as epigenetic modification of the LCR might play a role in inducing malignant transformation of cells containing episomal HPV16.

MiR-21 Upregulation Induced by Promoter Zone Histone Acetylation is Associated with Chemoresistance to Gemcitabine and Enhanced Malignancy of Pancreatic Cancer Cells

  • Song, Wei-Feng;Wang, Lei;Huang, Wei-Yi;Cai, Xun;Cui, Jiu-Jie;Wang, Li-Wei
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.14 no.12
    • /
    • pp.7529-7536
    • /
    • 2013
  • Background and Aims: MicroRNA-21 (miR-21) is reported to be overexpressed and to contribute to proliferation, apoptosis and gemcitabine resistance in pancreatic ductal adenocarcinomas (PDACs). The aims of this study were to explore regulation of miR-21 expression by epigenetic change and its impact on chemoresistance and malignant properties of of pancreatic cancer. Materials and methods: We retrospectively collected 41 cases of advanced pancreatic cancer patients who were sensitive or resistant to gemcitabine and assessed levels of serum circulating miR-21 for correlation with cytotoxic activity. Histone acetylation in the miR-21 promoter was also studied in gemcitabine-sensitive and gemcitabine-resistant PDAC cells. Gemcitabine-resistant HPAC and PANC-1 cells were transfected with pre-miR-21 precursors (pre-miR-21) and antisense oligonucleotides (anti-miR-21), and were treated with TSA. Finally, invasion and metastasis assays were performed and alteration in mir-21, PTEN, AKT and pAKT level was evaluated in these cells. Results: Serum miR-21 levels were increased in gemcitabine-resistant PDAC patients compared with gemcitabine-sensitive subjects. The miR-21 levels were increased in 6 PDAC cells treated with gemcitabine significantly, associated with 50% inhibitory concentrations ($IC_{50}s$). Histone acetylation levels at miR-21 promoter were increased in PDAC cells after treatment with gemcitabine. Enhanced invasion and metastasis, increased miR-21 expression, decreased PTEN, elevated pAKT level were demonstrated in gemcitabine-resistant HPAC and PANC-1 cells. Pre-miR-21 transfection or TSA treatment further increased invasion and metastasis ability, decreased PTEN, and elevated pAKT levels in these two lines. In contrast, anti-miR-21 transfection could reverse invasion and metastasis, and PTEN and pAKT expressions induced by gemcitabine. Conclusions: MiR-21 upregulation induced by histone acetylation in the promoter zone is associated with chemoresistance to gemcitabine and enhanced malignant potential in pancreatic cancer cells.

Epigenetic Study of XIST Gene from Female and Male Cells by Pyrosequencing (남성과 여성에서 XIST 유전자의 후성학적 비교 연구)

  • Kim, Hwan-Hee;Yun, Yeo-Jin;Song, Min-Ae;Lee, Su-Man
    • Clinical and Experimental Reproductive Medicine
    • /
    • v.37 no.1
    • /
    • pp.25-31
    • /
    • 2010
  • Objective: X inactivation is the silencing one of the two X chromosomes in female mammals for gene dosage on the X-chromosome between female and male. X inactivation is controlled by X inactive-specific transcript (XIST) gene, untranslated RNA. XIST is expressed only from the inactive X (Xi), not expressed from the active X (Xa). The Xist promoter is methylated on the silent Xist allele on the Xa in somatic cells, and less methylated on the Xist-expressing Xi. We investigated the difference of XIST methylation pattern of the promoter and 5'-region of XIST from male (XY) and female (XX) subjects. Methods: The direct quantification of XIST methylation is required for clinical application of normal XX and XY blood. Methylation percentage of eight CpG sites (-1696, -1679, -1475, -1473, -1469, +947, +956, +971) of XIST gene were diagnosed by pyrosequencing. Results: We directly quantitated the methylation percentage of the promoter and 5'-end of XIST by pyrosequencing. The average methylation percentages at CpG6-8 sites (+947, +956, +971) were 45.2% at CpG6, 49.9% at CpG7, and 44.2% at CpG8 from normal female and normal male were 90.6%, 96.7%, 87.8%, respectively. Nether CpG 1-5sites (-1696, -1679, -1475, -1473, -1469) had any effect on XX and XY. Conclusion: This method is sensitive for quantifying the small percentage change in the methylation status of XIST, and may be used for diagnosis.

Roles of Local Estrogen and Progesterone Mediated Receptors in the Regulation of Endometrial Inflammation (자궁내막 염증에 대한 지엽적 에스트로겐 및 프로게스테론 매개 수용체의 역할)

  • Gyesik Min
    • Journal of Life Science
    • /
    • v.33 no.1
    • /
    • pp.102-113
    • /
    • 2023
  • This review discusses the cellular and molecular mechanisms by which the endometrial estrogen and progesterone receptors regulate local estrogen production, expression of the specific estrogen receptors, progesterone resistance, inflammatory responses and the differentiation and survival of endometriotic cells in endometrial inflammation. The epigenetic aberrations of endometrial stromal cells play an important role in the pathogenesis and progression of endometriosis. In particular, differential methylation of the estrogen receptor genes changes in the stromal cells the dominancy of estrogen receptor from ERα into ERβ, and results in the abnormal estrogen responses including inflammation, progesterone resistance and the disturbance of retinoid synthesis. These stromal cells also stimulate local estrogen production in response to PGE2 and the SF-1 mediated induction of steroidogenic enzyme expression, and the increased estradiol then feeds back into the ERβ to repeat the vicious inflammatory cycle through the activation of COX-2. In addition, high levels of ERβ expression may also change the chromatin structure of endometrial mesenchymal stem cells, and together with the repeated menstrual cycles can induce formation of the endometriotic tissue. The cascade of these serial events then leads to cell adhesion, angiogenesis and survival of the differentiation-disregulated stromal cells through the action of inflammatory factors such as ERβ-mediated estrogen, TNF-α and TGF-β1. Therefore, understanding of the dynamic hormonal changes during the menstrual cycle and the corresponding signal transduction mechanisms of the related nuclear receptors in endometrium would provide new insights for treating inflammatory diseases such as the endometriosis.