• BMB Reports
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• 제44권1호
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• pp.70-75
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• 2011

Nucleolar and coiled-body phosphoprotein 1 (NOLC1) is a phosphoprotein that transiently associates with the mature nucleolar H/ACA and C/D box small nucleolar ribonucleoproteins (snoRNPs). Several lines of evidence indicate that NOLC1 plays an important role in the synthesis of rRNA and the biosynthesis of ribosomes. In the present study, we examined the transcriptional regulation mechanisms that govern the expression of NOLC1. We first performed functional dissection of the NOLC1 promoter. We demonstrated that transcription factors NF-${\kappa}B$ and CREB could bind to the minimal NOLC1 promoter. This was demonstrated by electrophoretic mobility shift assays and chromatin immunoprecipitation. Mutagenesis and overexpression assays revealed that NF-${\kappa}B$ and CREB positively regulated the NOLC1 promoter. These findings may provide new insight into the mechanisms that regulate NOLC1 expression.

• 대한한의학회지
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• 제23권1호
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• pp.50-60
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• 2002

Objectives: Sunghyangjunggisan (SHJS) is a commonly prescribed drug with a wide neuropharmacological spectrum. The water extracts of SHJS were found to be protective against neurotoxicity elicited by deprivation of serum and glucose. Methods: The morphological examination and Hoechst staining of nucleus also clearly showed that the extracts attenuated the cell shrinkage, membrane blebbing, representing typical neuronal apoptotic phenomena and nucleosome-sized fragmentation under the microscope in PC 12 rat pheochromocytoma cells. Results: Activation of protein kinase A (PKA) with dibutyl-cAMP and forskolin also protected during glucose deprivation, although it was not additive with the effect provided by phorbol ester. Interestingly, treatment with the protein kinase A inhibitor, KT5720, was not neuroprotective in the presence of SHJS. Electrophoretic mobility shift assays were used to characterize the neuroprotective binding of nuclear proteins to consensus sequences for AP-l, nuclear factor kappa B ($NF-{\kappa}B$) after glucose deprivation. When PC 12 cells are induced to undergo apoptosis by serum deprivation, AP-l and $NF-{\kappa}B$ DNA binding activity transiently increases to a slight degree. This stimulation is blocked by the water extracts of SHJS. The site of action of the drugs appeared to involve specific inhibition of AP-1 and nuclear factor kB binding activity. Conclusions: Taken together, these results suggested the possibility that the extracts of SHJS might provide a neurotrophic-like activity in PC 12 cells.

• BMB Reports
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• 제41권11호
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• pp.771-777
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• 2008

Calmodulin (CaM) proteins, members of the EF-hand family of $Ca^{2+}$-binding proteins, represent important relays in plant calcium signals. Here, OsCam1-1 was isolated by PCR amplification from the rice genome. The gene contains an ORF of 450 base pairs with a single intron at the same position found in other plant Cam genes. A promoter region with a TATA box at position-26 was predicted and fused to a gus reporter gene, and this construct was used to produce transgenic rice by Agrobacterium-mediated transformation. GUS activity was observed in all organs examined and throughout tissues in cross-sections, but activity was strongest in the vascular bundles of leaves and the vascular cylinders of roots. To examine the properties of OsCaM1-1, the encoding cDNA was expressed in Escherichia coli. The electrophoretic mobility shift when incubated with $Ca^{2+}$ indicates that recombinant OsCaM1-1 is a functional $Ca^{2+}$-binding protein. In addition, OsCaM1-1 bound the CaMKII target peptide confirming its likely functionality as a calmodulin.

• Journal of Microbiology and Biotechnology
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• 제17권2호
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• pp.342-347
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• 2007

Bacteriophage ${\Phi}FC1$ integrase (MJ1) was previously shown to perform a site-specific recombination between a phage attachment site (attP) and a host attachment site (attB) in its host, Enterococcus faecalis, and also in a non-host bacterium, Escherichia coli. Here, we investigated biochemical features of MJ1 integrase. First, MJ1 integrase could perform in vitro recombination between attP and attB in the absence of additional factors. Second, MJ1 integrase interacted with att sites. Electrophoretic mobility shift assays and DNase I footprinting revealed that MJ1 integrase could efficiently bind to all the att sites and that MJ1 integrase recognized relatively short sequences (${\sim}50bp$) containing an overlapping region within attB and attP. These results demonstrate that MJ1 integrase indeed catalyzes an integrative recombination between attP and attB, the mechanism of which might be simple and unidirectional, as found in serine integrases.

• Preventive Nutrition and Food Science
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• 제4권3호
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• pp.209-214
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• 1999

In this study, the effectof ethanol and acetaldehyde on DNA binding activities of NF-$textsc{k}$B and AP-1 were evaluated in C6 rat glial cells. Both NF-$textsc{k}$B and AP-1 are important transcription factors for the expression of various cytokines in glial cells. Our data showed that neither ethanol nor acetaldehyde induced conspicuous cell death of C6 cells at clinically realistic concentrations. When the DNA binding activities of nuclear NF-$textsc{k}$B and AP-1 were estimated using electrophoretic mobility shift assay (EMSA), ethanol(0.3%) or acetaldehyde(1mM) induced transient activation of these transcription factors, which attained peak levels at 4~8 hours and declined to basal levels at 12 hours after treatement . The supershift analysis showed that the increased activities of NF-$textsc{k}$B in ethanol/acetaldehyde-treated C6 cells were due to the preferential induction of p65/p50 heterodimer complex. The DNA binding activities of these transcriptional factors decreased below basal levels when cells were cultured with either ethanol or acetaldehyde for 24 hours, and showed the inhibitory effect of chronic ehtanol /acetaldehyde treatment on the activities of these transsriptional factors. Our data indicate that either ethanol or acetaldehyde can induce functional changes of glial cells throught bi-directional modulation of NF-$textsc{k}$B and AP-1 DNA binding activities.

• Animal cells and systems
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• 제3권3호
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• pp.311-317
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• 1999

Prolactin (PRL) was reported to be locally synthesized in many brain areas including the hypothalamus, thalamus (TH) and hippocampus (HIP). In the pituitary lactotrophs, PRL synthesis is dependent upon a pituitary-specific transcription factor, Pit-1. In the present study, we attempted to identify Pit-1 or Pit-1-like protein in brain areas known as the synthetic sites of PRL. Reverse transcription-polymerase chain reaction (RT-PCR) and Northern blot analysis showed the same Pit-1 transcripts in brain areas such as the medial basal hypothalamus (MBH), preoptic area (POA), TH, and HIP with the Pit-1 transcripts in the anterior pituitary (AP). Electrophoretic mobility shift assay (EMSA) was run with nuclear protein extracts from brain tissues using a double strand oligomer probe containing a putative Pit-1 binding domain. Shifted bands were found in EMSA results with nuclear proteins from MBH, POA, TH and HIP. Specific binding of the Pit-1-like protein was further confirmed by competition with an unlabeled cold probe. Antisense Pit-1 oligodeoxynucleotide (Pit-1 ODN), which was designed to bind to the Pit-1 translation initiation site and block Pit-1 biosynthesis, was used to test Pit-1 dependent brain PRL transcription. Two nmol of Pit-1 ODN was introduced into the lateral ventricle of a 60-day old male rat brain. RNA blot hybridization and in situ hybridization indicated a decrease of PRL mRNA signals by the treatment of Pit-1 ODN. Taken together, the present study suggests that Pit-1 may play an important role in the transcriptional regulation of local PRL synthesis in the brain.

• Molecules and Cells
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• 제26권5호
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• pp.496-502
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• 2008

Cryparin, encoded as a single copy gene (Crp) of the chestnut blight fungus Cryphonectria parasitica, is the most abundant protein produced by this fungus. However, its accumulation is decreased remarkably in C. parastica strains containing the double-stranded (ds) RNA virus Cryphonectria hypovirus 1. To characterize the transcriptional regulatory element(s) for strong expression and viral regulation, promoter analysis was conducted. Serial deletion of the Crp promoter region resulted in a step-wise decrease in promoter activity, indicating a localized distribution of genetic elements in the cryparin promoter. Promoter analysis indicated two positive and a repressive cis-acting elements. Among them, the promoter region between nt -1,282 and -907 appeared to be necessary for hypoviral-mediated down-regulation. An electrophoretic mobility shift assay (EMSA) on the corresponding promoter region (-1,282/-907) indicated two regions at (-1,257/-1,158) and (-1,107/-1,008) with the characteristic AGGAGGA-N42-GAGAGGA and its inverted repeat TCCTCTC-N54-TCCTCCT, respectively, appeared to be specific binding sites for cellular factors.

• Molecules and Cells
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• 제20권1호
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• pp.105-111
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• 2005

Mannasantin B, a dilignan structurally related to manssantin A, is an inhibitor of NF-${\kappa}B$ transactivation. In the present study, we found that it inhibited PMA-induced expression of IL-$1{\beta}$, IL-$1{\beta}$ mRNA, and IL-$1{\beta}$ promoter activity in U937 cells with $IC_{50}$ values of about 50 nM. It also inhibited NF-IL6- and NF-${\kappa}B$-induced activation of IL-$1{\beta}$, with $IC_{50}$ values of 78 nM and $1.6{\mu}M$, respectively, revealing a potent inhibitory effect on NF-IL6. Electrophoretic mobility shift assays showed that manassantin B had an inhibitory effect on DNA binding by NF-IL6, but not by NF-${\kappa}B$. Further analysis revealed that transactivation by NF-IL6 was also inhibited. Our results indicate that manassantin B suppresses expression of IL-$1{\beta}$ in promonocytic cells by inhibiting not only NF-${\kappa}B$ but also NF-IL6 activity. Furthermore, our observations suggest that manassantin B may be clinically useful as a potent inhibitor of NF-IL6 activity.

• Bulletin of the Korean Chemical Society
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• 제35권5호
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• pp.1279-1284
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• 2014

The binding of TATA-binding protein (TBP) to the TATA-box containing promoter region is aided by many other transcriptional factors including TFIIA and TFIIB. The mechanistic insight into the assembly of RNA polymerase II preinitation complex (PIC) has been gained by either directly altering a function of target protein or perturbing molecular interactions using drugs, RNAi, or aptamers. Aptamers have been found particularly useful for studying a role of a subset of PIC on transcription for their ability to inhibit specific molecular interactions. One major hurdle to the wide use of aptamers as specific inhibitors arises from the difficulty with traditional assays to validate and determine specificity, affinity, and binding epitopes for aptamers against targets. Here, using a technique called the bio-layer interferometry (BLI) designed for a label-free, real-time, and multiplexed detection of molecular interactions, we studied the assembly of a subset of PIC, TBP binding to TATA DNA, and two distinct classes of aptamers against TPB in regard to their ability to inhibit TBP binding to TFIIA or TATA DNA. Using BLI, we measured not only equilibrium binding constants ($K_D$), which were overall in close agreement with those obtained by electrophoretic mobility shift assay, but also kinetic constants of binding ($k_{on}$ and $k_{off}$), differentiating aptamers of comparable KDs by their difference in binding kinetics. The assay developed in this study can readily be adopted for high throughput validation of candidate aptamers for specificity, affinity, and epitopes, providing both equilibrium and kinetic information for aptamer interaction with targets.

• Asian-Australasian Journal of Animal Sciences
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• 제29권10호
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• pp.1383-1391
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• 2016

Bovine embryonic stem cells have potential for use in research, such as transgenic cattle generation and the study of developmental gene regulation. The Nanog may play a critical role in maintenance of the undifferentiated state of embryonic stem cells in the bovine, as in murine and human. Nevertheless, efforts to study the bovine Nanog for pluripotency-maintaining factors have been insufficient. In this study, in order to understand the mechanisms of transcriptional regulation of the bovine Nanog, the 5'-flanking region of the Nanog was isolated from ear cells of Hanwoo. Results of transient transfection using a luciferase reporter gene under the control of serially deleted 5'-flanking sequences revealed that the -134 to -19 region contained the positive regulatory sequences for the transcription of the bovine Nanog. Results from mutagenesis studies demonstrated that the Sp1-binding site that is located in the proximal promoter region plays an important role in transcriptional activity of the bovine Nanog promoter. The electrophoretic mobility shift assay with the Sp1 specific antibody confirmed the specific binding of Sp1 transcription factor to this site. In addition, significant inhibition of Nanog promoter activity by the Sp1 mutant was observed in murine embryonic stem cells. Furthermore, chromatin-immunoprecipitation assay with the Sp1 specific antibody confirmed the specific binding of Sp1 transcription factor to this site. These results suggest that Sp1 is an essential regulatory factor for bovine Nanog transcriptional activity.