• BMB Reports
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• 제41권7호
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• pp.511-515
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• 2008

The nucleocapsid (NC) protein of the Human Immunodeficiency Virus-1 plays a key role in viral genomic packaging by specifically recognizing the Psi($\Psi$) RNA sequence within the HIV-1 genome RNA. Recently, a novel cell-based assay was developed to probe the specific interactions in vivo between the NC and $\Psi$-RNA using E.coli cells (J. Virol. 81: 6151-55, 2007). In order to examine the extendibility of this cell-based assay to RNAs other than $\Psi$-RNA, this study tested the RNA aptamers isolated in vitro using the SELEX method, but whose specific binding ability to NC in a living cellular environment has not been established. The results demonstrate for the first time that each of those aptamer RNAs can bind specifically to NC in a NC zinc finger motif dependent manner within the cell. This confirms that the cell-based assay developed for NC-$\Psi$interaction can be further extended and applied to NC-binding RNAs other than $\Psi$-RNA.

• Molecules and Cells
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• 제39권3호
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• pp.179-185
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• 2016

Posttranscriptional regulation of RNA metabolism, including RNA processing, intron splicing, editing, RNA export, and decay, is increasingly regarded as an essential step for fine-tuning the regulation of gene expression in eukaryotes. RNA-binding proteins (RBPs) are central regulatory factors controlling posttranscriptional RNA metabolism during plant growth, development, and stress responses. Although functional roles of diverse RBPs in living organisms have been determined during the last decades, our understanding of the functional roles of RBPs in plants is lagging far behind our understanding of those in other organisms, including animals, bacteria, and viruses. However, recent functional analysis of multiple RBP family members involved in plant RNA metabolism and elucidation of the mechanistic roles of RBPs shed light on the cellular roles of diverse RBPs in growth, development, and stress responses of plants. In this review, we will discuss recent studies demonstrating the emerging roles of multiple RBP family members that play essential roles in RNA metabolism during plant growth, development, and stress responses.

• Asian-Australasian Journal of Animal Sciences
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• 제24권2호
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• pp.239-245
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• 2011

This study was conducted to determine the effects of excess vitamin A on alkaline phosphatase (ALP) activity, contents of calcium-binding protein (CaBP), bone gla-protein (BGP) in culture medium and CaBP mRNA expression in chicken osteoblasts in vitro. Osteoblastic cells in the tibia from 1-day-old Arbor Acre broiler chickens were isolated using enzyme digestion. The subconfluenced cells were divided into eight treatments with six replicates in each treatment and cultured in a medium containing either vehicle or different levels of vitamin A (0, 0.2, 0.6, 1.0, 2.0, 5.0, 10.0 and $20.0\;{\mu}g$/ml), and the control received an equivalent volume of ethanol. The incubation lasted 48 h. The results showed that vitamin A down-regulated ALP activity in the culture medium as well as CaBP mRNA expression of osteoblasts in a linear dose-dependent manner (p = 0.124 and p<0.10, respectively), and suppressed the contents of BGP and CaBP in the culture medium in a quadratic dose-dependent manner (p<0.05 and p<0.10, respectively) with increasing addition of vitamin A. The addition of 0-$0.2\;{\mu}g$/ml vitamin A to the culture medium increased ALP activity, BGP and CaBP contents as well as CaBP mRNA expression compared with other groups, but positive effects of vitamin A tended to be suppressed when vitamin A was increased to $1.0\;{\mu}g$/ml, and adverse effects occurred when vitamin A was increased to 10.0-$20.0\;{\mu}g$/ml. These results implied that there was a threshold level of vitamin A inclusion beyond which inhibitory effects occurred, and the mechanism by which overdose of vitamin A reduced bone growth in chickens was probably reduced osteoblastic cell activity, and inhibited expression of CaBP mRNA and CaBP secretion.

• 한국식물학회:학술대회논문집
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• 한국식물학회 1996년도 제10회 식물생명공학심포지움 고등식물 발생생물학의 최근 진보
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• pp.40-47
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• 1996

The promoters of a variety of plant genes are characterized by the presence of TGACG motif-containing sequences. These genes often exhibit quite diverse expression characteristics and in many case the TGACG-motif has been demonstrated to be essential for expression. Here we report the isolation and characterization of a soybean cDNA that encodes a novel basic/leucine zipper (bZIP) protein, STF1, that specifically interacts with Hex (TGACGTGG) and CRE (TGACGTCA) sequences. This protein contains a bZIP motif at C-teminus and an acidic domain at N-terminus. DNA binding specificities, heterodimer formation, and expression characteristics of STF1 were compared with a soybean TGA1 protein, STGA1. The soybean STF1 interacts with TGACG-sequences containing an ACGT core, while STGA1 requires TGACG as a sufficient binding sequence. The flanking sequences to the TGACG motif affected DNA binding of STF1 siginificantly. The STF1 mRNA is found mainly in dark grown soybean seedling with higher expression in apical and elongating hypocotyl, while STGA1 mRNA is highly abundant in roots of light grown plants. Furthermore, we demonstrate that STF1 heterodimerzes with G-box binding factorss (GBFs) which was not observed with TGA1. The fact that STF1 possesses both distinct DNA binding speficities and heterodimerization properties suggest that STF1 belongs to a new family of plant bZIP proteins which recognize the Hex/CRE motif.

• Bulletin of the Korean Chemical Society
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• 제27권2호
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• pp.224-230
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• 2006

Escherichia coli transcription termination factor Rho catalyzes the unwinding of RNA/DNA duplex in reactions that are coupled to ATP binding and hydrolysis. We report here the kinetic mechanism of presteady state ATP binding and hydrolysis by the Rho-RNA complex. Presteady state chemical quenched-flow technique under multiple turnover condition was used to probe the kinetics of ATP binding and hydrolysis by the Rho-RNA complex. The quenched-flow presteady state kinetics of ATP hydrolysis studies show that three ATPs are bound to the Rho-RNA complex with a rate of $4.4\;{\times}\;10^5M^{-1}s^{-1}$, which are subsequently hydrolyzed at a rate of $88s^{-1}$ and released during the initiation process. Global fit of the presteady state ATP hydrolysis kinetic data suggests that a rapid-equilibrium binding of ATP to Rho-RNA complex occurs prior to the first turnover and the chemistry step is not reversible. The initial burst of three ATPs hydrolysis was proposed to be involved in the initialization step that accompanies proper complex formation of Rho-RNA. Based on these results a kinetic model for initiation process for Rho-RNA complex was proposed relating the mechanism of ATP binding and hydrolysis by Rho to the structural transitions of Rho-RNA complex to reach the steady state phase, which is implicated during translocation along the RNA.

• BMB Reports
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• 제50권4호
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• pp.186-193
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• 2017

In mammals, cap-dependent translation of mRNAs is initiated by two distinct mechanisms: cap-binding complex (CBC; a heterodimer of CBP80 and 20)-dependent translation (CT) and eIF4E-dependent translation (ET). Both translation initiation mechanisms share common features in driving cap- dependent translation; nevertheless, they can be distinguished from each other based on their molecular features and biological roles. CT is largely associated with mRNA surveillance such as nonsense-mediated mRNA decay (NMD), whereas ET is predominantly involved in the bulk of protein synthesis. However, several recent studies have demonstrated that CT and ET have similar roles in protein synthesis and mRNA surveillance. In a subset of mRNAs, CT preferentially drives the cap-dependent translation, as ET does, and ET is responsible for mRNA surveillance, as CT does. In this review, we summarize and compare the molecular features of CT and ET with a focus on the emerging roles of CT in translation.

• 한국발생생물학회지:발생과생식
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• 제22권1호
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• pp.95-104
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• 2018

CREBZF (cAMP-response element binding protein zhangfei) is a member of ATF/CREB family, and which regulates various cellular functions by suppressing major factors with direct interaction. In this study, we have examined the expression of CREBZF on mouse endometrium during uterus estrous cycles and estrogen (E2) treatment. In uterus, CREBZF mRNA expression was higher than other organs and mRNA and protein of CREBZF was increased in proestrus phase and decreased in estrus phase. The expression of CREBZF in 3-weeks old mouse uterus was reduced by E2 injection in endometrium. In addition, the expression of progesterone receptor, a marker of E2 in ovariectomized mice was found to be strongly expressed in stroma, while CREBZF was only expressed in epithelium. Also, we conformed that E2-suppressed CREBZF was restored by co-injection of ICI 182,780, an estrogen receptor antagonist. Overall, these results suggest that CREBZF is regulated by estrogen and involved in ER signaling pathway in mouse uterus.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.1
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• pp.77-77
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• 2003

p43 is a protein with complex biological activities. It is first found as a protein associated with macromolecular tRNA synthetase complex. Within this complex, p43 specifically interacts with arginyl-tRNA synthetase to help the substrate tRNA binding to the enzyme. It is also necessary for the cellular stability of arginyl-tRNA synthetase and the molecular association of a few complex-forming tRNA synthetases. (omitted)

• Toxicological Research
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• 제31권2호
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• pp.191-201
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• 2015

We evaluated the inhibitory effect of Pueraria lobata root ethanol extract (PLREE) on lipid accumulation during 3T3-L1 differentiation to adipocytes by measuring the intracellular expression of adipogenic, lipogenic, and lipolytic markers and lipid accumulation. The total polyphenol and flavonoid content of PLREE were 47 and 29 mg/g, respectively. The electron donating capacity of PLREE at $1,000{\mu}g/mL$ was 48.8%. Treatment of 3T3-L1 preadipocytes with 100, 250, or $500{\mu}g/mL$ PLREE for 8 days dose-dependently promoted the differentiation of 3T3-L1 cells. In contrast, the lipid content of PLREE-treated cells was significantly reduced by 7.8% (p < 0.05), 35.6% (p < 0.001), and 42.2% (p < 0.001) following treatment with 100, 250, and $500{\mu}g/mL$ PLREE, respectively, as compared to differentiated control cells. PLREE upregulated peroxisome proliferator-activated receptor ${\gamma}$ mRNA and protein, and sterol regulator element-binding protein-1c mRNA levels, but did not affect CCAAT/enhancer binding-protein ${\beta}$ and ${\alpha}$ mRNA levels. PLREE also downregulated acetyl-CoA carboxylase mRNA and protein, fatty acid synthase (FAS) protein, and leptin mRNA levels, but did not affect FAS mRNA expression. PLREE upregulated adipose triglyceride lipase mRNA and protein expression, and hormone-sensitive lipase (HSL) protein expression, but did not affect HSL mRNA expression. In conclusion, we found that PLREE enhanced adipogenesis, but reduced lipogenesis, resulting in decreased lipid accumulation in 3T3-L1 cells.

• Asian Pacific Journal of Cancer Prevention
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• 제15권2호
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• pp.937-943
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• 2014

Polymorphisms in miRNA binding sites have been shown to affect miRNA binding to target genes, resulting in differential mRNA and protein expression and susceptibility to common diseases. Our purpose was to predict SNPs (single nucleotide polymorphisms) within miRNA binding sites of inflammatory genes in relation to gastric cancer. A complete list of SNPs in the 3'UTR regions of all inflammatory genes associated with gastric cancer was obtained from Pubmed. miRNA target prediction databases (MirSNP, Targetscan Human 6.2, PolymiRTS 3.0, miRNASNP 2.0, and Patrocles) were used to predict miRNA target sites. There were 99 SNPs with MAF>0.05 within the miRNA binding sites of 41 genes among 72 inflammation-related genes associated with gastric cancer. NF-${\kappa}B$ and JAK-STAT are the two most important signaling pathways. 47 SNPs of 25 genes with 95 miRNAs were predicted. CCL2 and IL1F5 were found to be the shared target genes of hsa-miRNA-624-3p. Bioinformatic methods could identify a set of SNPs within miRNA binding sites of inflammatory genes, and provide data and direction for subsequent functional verification research.