• Molecules and Cells
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• 제28권4호
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• pp.341-345
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• 2009

MiRNAs are non-coding RNAs that play a role in the regulation of major processes. The inhibition of miRNAs using antisense oligonucleotides (ASOs) is a unique and effective technique for the characterization and subsequent therapeutic targeting of miRNA function. Recent advances in ASO chemistry have been used to increase both the resistance to nucleases and the target affinity and specificity of these ASOs. Peptide nucleic acids (PNAs) are artificial oligonucleotides constructed on a peptide-like backbone. PNAs have a stronger affinity and greater specificity to DNA or RNA than natural nucleic acids and are resistant to nucleases, which is an essential characteristic for a miRNA inhibitor that will be exposed to serum and cellular nucleases. For increasing cell penetration, PNAs were conjugated with cell penetrating peptides (CPPs) at N-terminal. Among the tested CPPs, Tat-modified peptide-conjugated PNAs have most effective function for miRNA inhibition. PNA-based ASO was more effective miRNA inhibitor than other DNA-based ASOs and did not show cytotoxicity at concentration up to 1,000 nM. The effects of PNA-based ASOs were shown to persist for 9 days. Also, PNA-based ASOs showed considerable stability at storage temperature. These results suggest that PNA-based ASOs are more effective ASOs of miRNA than DNA-based ASOs and PNA-based ASO technology, compared with other technologies used to inhibit miRNA activity can be an effective tool for investigating miRNA functions.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1995년도 춘계학술대회
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• pp.78-78
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• 1995

Increasing evidence indicates that the production of nitric oxide (NO) by inducible NO synthase (NOS) is tightely regulated. Transforming growth factor-${\beta}$ (TGF-${\beta}$) is a homodimeric protein secreted during macrophage activation, but several lines of evidence suggest that TGF-${\beta}$ is selectively suppressive for macrophage NO production. We therefore reasoned that a strategy employing oligodeoxynucleotides(ODNs) complemently to TGF-${\beta}$ mRNA (antisense ODNs) might increase NO production in IFN-${\gamma}$-treated murine peritoneal macrophages. To evaluate this concept, we tested the effects of antisense ODNs targeted to TGF-${\beta}$ mRNA (25-mer ODNs complemently to TGF-${\beta}$mRNA sequences) by introducing it into the medium of cultured macrophages. Phosphorothiolation of ODNs were employed to retard their degradation. Antisense ODNs had no effect on NO production by itself, whereas IFN-${\gamma}$ alone had modest effect. When antisense ODNs were used in combination with IFN-${\gamma}$, there was a marked cooperative induction of NO production, These effects of antisense ODNs were associated with decreased TGF-${\beta}$ expression in activated macrophages. ODNs with the same nucleotides but a scrambled sequence had no effect. Adding anti-TGF-${\beta}$ antibodies to the IFN-${\gamma}$-treated macrophages mimicked the positive effect of antisense ODNs on NO production. In addition, the effects of either antisense ODNs or anti-TGF-${\beta}$ antibodies were blocked by adding TGF-${\beta}$ in cultured macrophages. These results indicate that the generation of TGF-${\beta}$ by activated macrophages provides a self-regulating mechanism by which the temporal and perhaps spatial production of NO, a reactive and potentially toxic mediator, can be finely regulated.

• 식물조직배양학회지
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• 제25권3호
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• pp.147-152
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• 1998

AL1-gene은 TGMV의 복제에 매우 중요한 역할을 하고 있다. 이 AL1 gene의 발현을 억제하기 위해서는 식물체내에서 AL1 gene의 antisense RNA의 발현에 의한 억제가 효과적 방법 중에 하나로 알려져 있다. 이런 발현을 식물체내에서 실현시키기 위해 hygromycin 저항성 유전자에 antisense AL1-gene을 연결시키고, 연결된 부위를 CaMV35s-promoter와 octopine synthase gene terminator 사이에 연결시켰다. 이 유전자 발현 단위 부분을 다시 kanamycin 저항성 유전자 발현 단위 부분을 지니고 있는 형질 전환 벡터인 pBinAR에 삽입시켜 새로운 형질 전환 벡터인 pAR35-2를 개발하였다. 이 벡터를 Agrobacterium tumefaciens LBA4404에 형질전환 시킨 다음, 토마토와 담배 잎사귀 조직에 감염시켜 식물체들을 kanamycin과 hygromycin이 함유된 배지위에서 배양하여 형질전환된 식물체들을 선발하였다. 형질 전환된 식물체들로부터 antisense AL1-gene 및 antisense RNA를 각각 PCR 및 RT-PCR를 이용한 southern hybridization 방법을 이용하여 증명하였고, 토마토 식물체의 공변세포쌍 내에 있는 엽록체 숫자가 여덟 개라는 것이 확인되어 형질 전환된 토마토 식물체가 2 배수체로서 정상적인 식물체라는 것을 증명하였다. 이러한 형질 전환 식물체는 앞으로 항 바이러스성 형질을 지니는 식물체들을 개발하는 데 많은 도움을 주리라 여겨 진다. 그리고, 본 연구에서 제조된 벡터 pAR35-2는 두 개의 항생제에서 동시 선발 할 수 있도록 되어 있고 promoter가 두 개로 되어 있어 형질 전환 식물체선발 및 유전자 발현 연구에 효과적으로 이용되어 질 수 있으리 라 여겨진다.

• BMB Reports
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• 제28권3호
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• pp.243-248
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• 1995

Cholesteryl ester transfer protein (CETP), a hydrophobic glycoprotein promoting transfer of cholesteryl esters (CE) from high-density lipoproteins (HDL) to lower-density lipoproteins in the plasma, has been recognized a potent atherogenic factor during the development of coronary artery diseases. This study demonstrated a possible utilization of antisense RNA to inhibit expression of the CETP gene using vaccinia virus as an expression system. The CETP cDNA was inserted into a transfer vector (pSC11) in sense and antisense orientations and used to generate recombinant viruses. Recombinants containing sense or antisense orientations of the CETP cDNA were isolated by $TK^-$ selection and X-gal test. The inserted CETP cDNAs in the recombinants were identified by Southern blot analysis and allowed to transcribe in host cells (CV-1). Expressions of the exogenous CETP mRNA, extracted from the CV-1 cells coinfected with viruses containing sense and antisense DNAs, were monitored by Northern blot analysis using the CETP cDNA probe, by Western blot analysis using monoclonal antibody against the C-terminal active region of the CETP and by the CETP assay. Decreased expressions of the exogenous CETP cDNA were clearly evident in the Northern and Western blot analyses as the dose of antisense expression increased. In the CETP assay, the CETP activities decreased compared to the activity obtained from the cell extracts infected with sense construct only.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1995년도 춘계학술대회
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• pp.79-79
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• 1995

Although synthetic antisense oligodeoxynucleotides (ODNs) have been used to dissect gene function in vitro, technical difficulties of targeted delivery prevented the use of this approach for investigating the effect of gene products in vivo. Here we report the use of local delivery of antisense transforming growth factor-${\beta}$l (TGF-${\beta}$1) oligonucleotides to decrease the fibrosis in the skin wound. Adult wounds heal with scar-tissue formation, whereas fetal wounds heal without scarring and with a lesser inflammatory and cytokine response. We reasoned that strategy emptying antisense TGF-${\beta}$1 ODNs complementary to TGF-${\beta}$1 mRNA might decrease the scarring in dermal wound of mouse. To evaluate this concept, we tested the effects of antisense ODNs targeted to TGF-${\beta}$1 mRNA by topical application of the chemical on the skin wound. Phosphorothioate antisense ODNs was employed to retard their degradation. When antisense TGF-${\beta}$1 ODNs were applied into the wound site, there was a maked reduction of scar compared with control wound site, These effects of antisense TGF-${\beta}$1 ODNs on the scar formation were associated with decreased expression of TGF-${\beta}$1 gene. However sense TGF-${\beta}$l ODNs had no effect on expression of TGF-${\beta}$1 gene. Also, control wounds healed with excessive fibrosis, whereas the antisense treated wounds healed with less fibrosis. In conclusion, our results indicate that antisense TGF-${\beta}$1 ODNs could be used for amelioating scar formation during wound healing.

• The Korean Journal of Physiology and Pharmacology
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• 제12권1호
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• pp.1-6
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• 2008

Ribbon-type antisense oligonucleotide to TGF-${\beta}1$ (TGF-${\beta}1$ RiAS) was designed and tested to prevent or resolve the fibrotic changes induced by $CCl_4$ injection. When Hepa1c1c7 cells were transfected with TGF-${\beta}1$ RiAS, the level of TGF-${\beta}1$ mRNA was effectively reduced. TGF-${\beta}1$ RiAS, mismatched RiAS, and normal saline were each injected to mice via tail veins. When examined for the biochemical effects on the liver, TGF-${\beta}1$ mRNA levels were significantly reduced only in the TGF-${\beta}1$ RiAS-treated group. The results of immunohistochemical studies showed that TGF-${\beta}1$ RiAS prevented the accumulation of collagen and ${\alpha}$-smooth muscle actin, but could not resolve established fibrosis. These results indicate that ribbon antisense to TGF-${\beta}1$ with efficient uptake can effectively prevent fibrosis of the liver.

• Journal of Microbiology and Biotechnology
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• 제12권1호
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• pp.89-95
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• 2002

Telomerase is a ribonucleoprotein complex, whose function is to add telomeric repeats $(TTAGGG)_n$ to chromosomal ends and is also known to play an important role in cellular immortalization. Telomerase is highly active in most tumor cells, yet not in normal cells. Therefore, it may have possible applications in cancer gene therapy. Telomerase consists of two essential components; a telomerase RNA template (hTR) and a catalytic subunit (hTERT). The current study attempted to inhibit the "open" part of the human telomerase RNA (hTR) with an antisense sequence-expressing adenovirus. It was found that the antisense telomerase adenovirus suppressed the telomerase activity, tumor cell growth, and survival in vitro. Furthermore, FACS analysis and TUNEL assay suggested that the reduce viability was mediated through the induction of apoptosis, indicating that this approach might be a useful method for suppressing cancer growth in targeted cancer gene therapy.

• Molecules and Cells
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• 제43권12호
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• pp.975-988
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• 2020

Hypoxia plays important roles in cancer progression by inducing angiogenesis, metastasis, and drug resistance. However, the effects of hypoxia on long noncoding RNA (lncRNA) expression have not been clarified. Herein, we evaluated alterations in lncRNA expression in lung cancer cells under hypoxic conditions using lncRNA microarray analyses. Among 40,173 lncRNAs, 211 and 113 lncRNAs were up- and downregulated, respectively, in both A549 and NCI-H460 cells. Uroplakin 1A (UPK1A) and UPK1A-antisense RNA 1 (AS1), which showed the highest upregulation under hypoxic conditions, were selected to investigate the effects of UPK1A-AS1 on the expression of UPK1A and the mechanisms of hypoxia-inducible expression. Following transfection of cells with small interfering RNA (siRNA) targeting hypoxia-inducible factor 1α (HIF-1α), the hypoxia-induced expression of UPK1A and UPK1A-AS1 was significantly reduced, indicating that HIF-1α played important roles in the hypoxia-induced expression of these targets. After transfection of cells with UPK1A siRNA, UPK1A and UPK1A-AS1 levels were reduced. Moreover, transfection of cells with UPK1A-AS1 siRNA downregulated both UPK1A-AS1 and UPK1A. RNase protection assays demonstrated that UPK1A and UPK1A-AS1 formed a duplex; thus, transfection with UPK1A-AS1 siRNA decreased the RNA stability of UPK1A. Overall, these results indicated that UPK1A and UPK1A-AS1 expression increased under hypoxic conditions in a HIF-1α-dependent manner and that formation of a UPK1A/UPK1A-AS1 duplex affected RNA stability, enabling each molecule to regulate the expression of the other.

• BMB Reports
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• 제50권4호
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• pp.220-225
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• 2017

Antisense transcripts were initially identified as transcriptional noise, but have since been reported to play an important role in the quality control of miRNA functions. In this report, we tested the hypothesis that heterogeneous nuclear ribonucleoprotein K (hnRNPK) regulates miRNA function via competitive endogenous RNAs, such as pseudogenes, long non-coding RNAs, and antisense transcripts. Based on analyses of RNA sequencing data, the knockdown of hnRNPK decreased the antisense PTOV1-AS1 transcript which harbors five binding sites for miR-1207-5p. We identified heme oxygenase-1 (HO-1) mRNA as a novel target of miR-1207-5p by western blotting and Ago2 immunoprecipitation. The knockdown of hnRNPK or PTOV1-AS1 suppressed HO-1 expression by increasing the enrichment of HO-1 mRNA in miR-1207-5p-mediated miRISC. Downregulation of HO-1 by a miR-1207-5p mimic or knockdown of hnRNPK and PTOV1-AS1 inhibited the proliferation and clonogenic ability of HeLa cells. Taken together, our results demonstrate that hnRNPK-regulated PTOV1-AS1 modulates HO-1 expression via miR-1207-5p.

• 대한의생명과학회지
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• 제10권2호
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• pp.65-73
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• 2004

I report that single-stranded antisense as a part of large circular (LC-) genomic DNA of recombinant M13 phage exhibits enhanced stability, sequence specific antisense activity, and no need for target site search. A cDNA fragment (708 bp) of rat TNF-$\alpha$ was inserted into a phagemid vector, and TNF-$\alpha$ antisense molecules (TNF$\alpha$-LCAS) were produced as single-stranded circular DNA. When introduced into a rat monocyte/macrophage cell line, WRT7/P2, TNF$\alpha$-LCAS was able to ablate LPS-induced TNF-$\alpha$ mRNA to completion. The antisense effect of TNF$\alpha$-LCAS was shown to be sequence-specific because expressions of three control genes ($\beta$-actin, GAPDH and IL-1$\beta$) were not significantly altered by the antisense treatment. Further, TNF$\alpha$-LCAS was found to be highly efficacious as only 0.1 $\mu$g (0.24 nM) of TNF$\alpha$-LCAS was sufficient to block TNF-$\alpha$ expression in 1$\times10^5$ WRT7/P2 cells. I have also observed specific antisense activity in reduction of NF-$\kappa$B gene expression. The results suggest that an antisense sequence as a part of single-stranded circular genomic DNA has a specific antisense activity.