• Journal of Microbiology
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• v.35 no.4
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• pp.315-322
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• 1997

The effects of a polyamine, spermine, on the differentiation of Naegleria gruberi amebas into flagellates were tested. Addition of spermine at early stages of differentiation (until 40 min after the initiation of differentiation) completely inhibited the differentiation. To understand the inhibition mechanism, we examined the effect of spermine treatment on the transcription and translation of differentiation-specific genes during differentiation. Addition of spermine at early stages did not inhibit the accumulation of two differentiation-specific mRNAs, ${\alpha}$-tubulin and Class I mRNA, significantly, but rather prevented the rapid degradation of the mRNAs in later overall protein synthesis partially and gradually. However, translation of the ${\alpha}$-tubulin mRNA was completely inhibited. These data suggest that the inhibition of differentiation of N. gruberi by spermine treatment did not result from the inhibition of transcription of differentiation-specific genes but from the specific inhibition of translation of the mRNAs during the differentiation.

• BMB Reports
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• v.51 no.12
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• pp.613-622
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• 2018

RNA helicases DDX5 and DDX17 are multitasking proteins that regulate gene expression in different biological contexts through diverse activities. Special attention has long been paid to their function as coregulators of transcription factors, providing insight about their functional association with a number of chromatin modifiers and remodelers. However, to date, the variety of described mechanisms has made it difficult to understand precisely how these proteins work at the molecular level, and the contribution of their ATPase domain to these mechanisms remains unclear as well. In light of their association with long noncoding RNAs that are key epigenetic regulators, an emerging view is that DDX5 and DDX17 may act through modulating the activity of various ribonucleoprotein complexes that could ensure their targeting to specific chromatin loci. This review will comprehensively describe the current knowledge on these different mechanisms. We will also discuss the potential roles of DDX5 and DDX17 on the 3D chromatin organization and how these could impact gene expression at the transcriptional and post-transcriptional levels.

• Korean Journal of Pharmacognosy
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• v.52 no.3
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• pp.143-148
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• 2021

This study was performed to elucidate the inhibitory effects of Alveopora japonica extract on melanin synthesis by measuring the levels of cell viability, mRNA expression, tyrosinase activity, and melanin production in the B16F10 cell line. The effects of A. japonica extract on tyrosinase-related protein 1 (TYRP1), TYRP2, tyrosinase (TYR), and microphthalmia-associated transcription factor (MITF) mRNA expression levels and melanin content were determined. Quantitative real-time RT-PCR show that A. japonica extract decrease the mRNA expression levels of TYRP1, TYRP2, TYR, and MITF in B16F10 cell line, resulting in lower levels of melanin production compared to α-MSH-treated B16F10 cells. Tyrosinase activity assays reveal that A. japonica extract decrease melanin production in B16F10 cells. These results demonstrate the whitening effects of A. japonica extract on B16F10 cells; thus, A. japonica extract is a potent ingredient for skin whitening. Further research is needed on the mechanism of action of A. japonica extract. Such research will benefit not only cosmetics, but also the health food and medical industries.

• Korean Journal of Pharmacognosy
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• v.52 no.1
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• pp.13-18
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• 2021

This study was performed to clarify the whitening effects of anthricin on the B16F10 cell line. In order to elucidate the whitening effects of anthricin on the B16F10 cell line, cell viability, messenger ribonucleic acid (mRNA) expressions, tyrosinase activity assay, and melanin production assay were measured. The effects of anthricin on tyrosinase-related protein 1(TYRP1)/TYRP2/tyrosinase (TYR)/microphthalmia-associated transcription factor (MITF) mRNA expressions and melanin content were determined. Quantitative real-time RT-PCR showed that anthricin decreased the mRNA expression level of TYRP1/TYRP2/TYR/MITF genes and melanin production contents than α-MSH-treated B16F10 cells. The tyrosinase activity assay revealed that anthricin decreased the melanin production on the B16F10 cells. These data show that anthricin increases the whitening effects on the B16F10 cells; thus, anthricin is a potent ingredient for skin whitening. Thus, further research on the mechanism of action of anthricin for the development of not only cosmetics, but also healthy food and medicine should be investigated.

• Korean Journal of Pharmacognosy
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• v.52 no.2
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• pp.99-104
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• 2021

This study was performed to elucidated the inhibitory effects of 6,8-diprenylorobol on melanin synthesis by measuring the levels of cell viability, mRNA expression, tyrosinase activity, and melanin production in the B16F10 cell line. The effects of 6,8-diprenylorobol on tyrosinase-related protein 1 (TYRP1), TYRP2, tyrosinase (TYR), and microphthalmia-associated transcription factor (MITF) mRNA expression levels and melanin content were determined. Quantitative real-time RT-PCR shows that 6,8-diprenylorobol decreases the mRNA expression levels of TYRP1, TYRP2, TYR, and MITF in B16F10 cell line, resulting in lower levels of melanin production compared to α-MSH-treated B16F10 cells. Tyrosinase activity assays reveal that 6,8-diprenylorobol decreases melanin production in B16F10 cells. These results demonstrate the whitening effects of 6,8-diprenylorobol on B16F10 cells; thus, 6,8-diprenylorobol is a potent ingredient for skin whitening. Further research is needed on the mechanism of action of 6,8-diprenylorobol. Such research will benefit not only cosmetics, but also the health food and medical industries.

• Journal of Microbiology
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• v.41 no.4
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• pp.300-305
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• 2003

Intracellular expression of RNA decoys, such as TAR or RRE decoy, has been previously shown to protect immune cells from human immunodeficiency virus type 1 (HIV-1) replication by inhibiting the binding of the HIV-1 regulatory protein to the authentic HIV RNA sequence. However, HIV-1 challenge experiments of primary human T cells, which express the RNA decoy, demonstrated that the cells were only transiently protected, and hence, more improved protocols for HIV-1 inhibition with the RNA decoys need to be developed. In this report, in order to develop a more effective RNA decoy, we analyzed and compared the ability of a series of RNA decoy derivatives in inhibiting HIV-1 replication in CEM cells. Using an improved tRNA cassette to express high levels of RNA decoy transcripts in cells, we found that co-expression of both TAR and RRE decoys, in the form of an aligned sequence in a single transcription cassette, much more potently blocked cells from HIV-1 than the expression of only one kind of RNA decoy. This observation will have an important implication for experiments involving optimization of clinical applications in RNA decoy-based gene therapy against HIV-1.

• Annals of Clinical Microbiology
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• v.19 no.1
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• pp.20-23
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• 2016

In the RNA-based study, it is important to extract high-quality RNA. However, RNA extraction from Mycobacterium tuberculosis is problematic due to its thick, waxy cell wall rich in mycolic acid, which renders the cells resistant to lysis. Using TRIzol reagent and several powerful bead-beating steps, a high quantity of RNA was obtained.

• Mass Spectrometry Letters
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• v.13 no.4
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• pp.115-124
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• 2022

Emerging evidence has shown that RNA-binding proteins (RBPs) dynamically regulate all aspects of RNA in cells and involve in major biological processes of RNA, including splicing, modification, transport, transcription and degradation. RBPs, as powerful and versatile regulatory molecule, are essential to maintain cellular homeostasis. Perturbation of RNA-protein interactions and aberration of RBPs function is associated with diverse diseases, such as cancer, autoimmune disease, and neurological disorders. Therefore, it is crucial to systematically investigate the RNA-binding proteome for understanding interactions of RNA with proteins. Thanks to the development of the mass spectrometry, a variety of proteome-wide methods have been explored to define comprehensively RNA-protein interactions in recent years and thereby contributed to speeding up the study of RNA biology. In this review, we systematically described these methods and summarized the advantages and disadvantages of each method.

• Proceedings of the Korean Information Science Society Conference
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• 1999.10b
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• pp.12-14
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• 1999

Promoter는 transcript start site 앞부분에 위치하여 RNA polymerase가 높은 친화성을 보이며 바인당하는 DNA상의 특별한 부위로서 여기서부터 DNA transcription이 시작된다. function이나 tissue-specific gene들의 그룹별로 그 promoter들의 특이한 패턴들의 조합을 발견함으로써 Specific한 transcription을 조절하는 것으로 알려져 있어 promoter로 인한 그 gene의 정보를 어느 정도 알 수가 있다. 사람의 housekeeping gene promoter들을 EPD(eukaryotic promoter database)와 EMBL nucleic acid sequence database로부터 수집하여 이것들 간에 의미 있게 나타나는 모든 패턴들을 optimization algorithm으로 알려진 genetic algorithm을 이용해서 찾아보았다.

• Journal of Animal Reproduction and Biotechnology
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• v.34 no.4
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• pp.292-299
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• 2019

Interferon tau (IFNT) regulation, an anti-luteolytic factor produced by conceptuses of the ruminant ungulates, is essential for the maintenance of early pregnancy, but a definitive mechanism for its temporal transcription has not been elucidated. We and others have observed the T-box protein eomesodermin (EOMES) exhibited high mRNA expression in the ovine embryonic trophectoderm; thus, both caudal-relatedhomeobox-2 (CDX2) and EOMES coexist during the early stages of conceptus development. Objective of this study was to examine the effect of EOMES on ovine IFNT gene transcription when evaluated with CDX2, ETS2 and AP1 transcription factors implicated in the control of cell differentiation in the trophectoderm. In this study, quantitatively via reverse transcription-polymerase chain reaction (RT-PCR) analysis between ovine trophoblast cells was initially performed, finding that transcription factors CDX2 and 'EOMES transcription factor mRNAs' were specific to trophectoderm cells. These mRNAs were also found in days 15, 17, and 21 ovine conceptuses. Furthermore, human choriocarcinoma JEG3 cells (trophoblast cell line) were cotransfected with an ovine IFNT (-654bp)-luciferase reporter (-654-oIFNT-Luc) construct and several transcription factor expression plasmids. Cotransfection of the reporter construct with CDX2, ETS2 and AP1 increased transcription of -654-oIFNT-Luc by about 11-fold compared with transfection of the construct alone. When cells were initially transfected with EOMES followed by transfection with CDX2, ETS2 and/or AP1, the expression of -654-oIFNT-Luc was decreased. Also, EOMES factor inhibited the stimulatory activity of CDX2 alone. These results suggest that when conceptuses attach to the uterine epithelium, ovine IFNT gene transcription is down-regulated by an increase of EOMES factor expression in the attached ovine trophoblast cells.