• BMB Reports
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• v.29 no.5
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• pp.468-473
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• 1996

The P38 promoter of minute virus of mice (MVM) is a very weak promoter which is strongly transactivated by viral nonstructural proteins. To analyze the upstream sequence of the P38 promoter which is responsible for the transactivation by nonstructural proteins in MVM, chloramphenicol acetyltransferase (CAT) reporter plasm ids containing a series of 5' deletion and internal deletion mutants of the P38 promoter were constructed. The wild type and mutant CAT constructs of P38 promoter were cotransfected into murine A92L fibroblast cells with a plasmid expressing viral nonstructural proteins by DEAE-dextran method. Each promoter activity was analyzed by CAT assay. As previously reported (Ahn et al., 1992), the proximal DNA cis-elements required for transactivation of the MVM P38 promoter are GC box and TATA box. However, the analysis of 5' deletion mutants showed that H-l tar like sequence (MVM TAR) which is located between -143 and -122 relative to the transcription initiation site is also required for transactivation of the P38 promoter by nonstructural proteins. Interestingly, even if the MVM TAR was removed by internal deletion, the level of the transactivation is still 70% of wild type level of transactivation. We also found that, in addition to the MVM TAR motif, there are two other motifs which are similar to the MVM TAR sequence. When these TAR like motifs were further deleted, the levels of transactivation were decreased further. Taken together, the MVM TAR sequence and TAR like motifs located upstream of P38 promoter are playing an important role for the transactivation of P38 promoter by nonstructural proteins in minute virus of mice.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.38 no.2
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• pp.101-109
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• 2012

Objectives: The inactivation of the tumor suppressor gene $p16^{INK4a}$ plays an important role in the development of malignant tumors, including oral squamous cell carcinoma. The p16 gene is involved in the p16/cyclin-dependent kinase/retinoblastoma (Rb) gene pathway of cell cycle control. The p16 protein is considered a negative regulator of this pathway. The p16 gene encodes an inhibitor of cyclin-dependent kinases 4 and 6 which regulate the phosphorylation of the retinoblastoma gene and G1 to S phase transition in the cell cycle. However, the p16 gene can lose its functionality through point mutations, loss of heterozygosity or methylation of its promoter region. Materials and Methods: In this study, the authors analyzed the correlation between various clinicopathological findings- patient age, gender and smoking, disease recurrence, tumor size, stage, and differentiation- and p16 protein expression or p16 promoter hypermethylation in 59 cases of head and neck squamous cell carcinoma. Results: The results revealed p16 protein expression and p16 promoter hypermethylation in 28 cases (47.5%) and 21 cases (35.6%), respectively, of head and neck squamous cell carcinoma. However, neither p16 protein expression nor p16 promoter hypermethylation had any statistical influence on clinicopathological findings or survival rate. Conclusion: This data, and a review of the literature, suggest that p16 promoter hypermethylation cannot yet be used as an independent prognostic factor influencing carcinogenesis, but must be considered as an important factor along with other genetic alterations affecting the pRb pathway.

• Korean Journal of Microbiology
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• v.38 no.4
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• pp.318-321
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• 2002

To induce recombinant protein under phosphate restricted conditions such as soil, we have constructed the expression vector (pEAAP) with phoA gene promoter of Enterobacter aerogenes. To construct the pEAAP, deletion of the T7 promoter and lac operator from pET-22b(+) by BglII-XhoI digestion and addition of the phoA gene promoter (containing the pho box) were performed. To test pEAAP as an expression vector controled by phosphate limitation, pEAPHY1 was constructed with the phytate gene (Bsa-phy1) of Bacillus subtillis var. amyloliquefaciens (KCTC 8913P). Under the phosphate-limitation condition, CK-PHY1 ( Escherichia coli JM109 was transformed with pEAPHY1) expressed the 41 kD Bsa-Phy1 . Also CK-PHY1 formed the clear zone in solid medium containing phytate as a sole phosphate source.

• Journal of Plant Biology
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• v.38 no.4
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• pp.365-371
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• 1995

Binary vectors, pBI-ActR1, pBI-ActF1 and pBSH-ActR1, were constructed using pGA642, the replication origin of pTi12 and the rice actin promoter. The sizes of pBI-ActR1, pBI-ActF1 and pBSH-ActR1 were 12.9 kb, 13.2 kb and 11.95 kb, respectively. These vectors containing a rice actin promoter followed by a GUS structural gene could induce stronly the expression of GUS gene in transformed rice cells. Rice explants from 3-4 day old seedlings after germinatin were cocultured with A. tumefaceins harboring pBI-ActR1, pBI-ActF1 or pBSH-ActR1, and then GUS expression in the explants was assayed. Transformation of rice explants by these binary vectors was tissue-specific, such that the meristematic regions of shoot apex, root and hypocotyl were transformed by these binary vectors.

• Journal of Microbiology
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• v.38 no.3
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• pp.176-179
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• 2000

A challenge phage system was used to study the DNA-protein interaction between C4-dicarboxylic acid transport protein D(DCTD) or $\sigma$54, and a $\sigma$54 -dependent promoter, dctAp. R. meliloti dctA promoter regulatory region replaced the Omnt site on the phage. S. typhimurium strains overproducing either DCTD or $\sigma$54 directed this challenge phage towards lysogency, indicating that DCTD or E$\sigma$54 recognized the dctA promoter on the phage and repressed transcription of the ant gene. These challenge phage constructs will be useful for examining interactions between DCTD(or $\sigma$54) and the dctA promoter region.

• Journal of Plant Biology
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• v.38 no.3
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• pp.259-266
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• 1995

To investigate how the dyad symmetry region (DSR) and the distance between vir box and -35 sequence of the virE promoter plays a role in virE gene expression, two mutants were constructed by base substitution and insertional mutagenesis. The base substitutional mutation, a AAlongrightarrowCG substitution at positions -39 and -40 on the DSR, showed the level of $\beta$-galactosidase activity approximately 91% of the wild type virE promoter activity. Therefore, the native structure of the DSR seems to be not essential for virE expression. The insertional mutation, constructed by inserting 8 bp ClaI linker between -49 and -50, displayed the $\beta$-galactosidase activity at 12% of the native virE promoter activity. However, this striking reduction appears to be not caused by destruction of the native DSR structure, but by shifting the vir box far from putative -35 sequence.

• Journal of Plant Biology
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• v.38 no.1
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• pp.107-113
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• 1995

pRLYS1 containing intact rbcL gene of maize (Zea mays L. cv Golden X Bantam T-51; Zm-A) was digested with several restriction enzymes to construct subcones carrying promoter region of rbcL. The DNA fragments of 0.20, 0.19, 0.92 and 1.55 kb among the EcoRI digests, the EcoRI-DdeI digests, the AvaI digests and the EcoRI-BamHI digests of pRLYS1 were subcloned into pBluscriptSK＋and named pRLPS2, pRLPS3, pRLPS14 and pRLPS35, respectively. Four subclones contain the 1.92 kb portion from 136 nucleotide downstream to 1780 nucleotide upstream from the ATG initiation codon of rbcL gene. pRLPS2 (-29 to -229) and pRLPS3 (-239 to -420 from the ATG) were sequenced. When nucleotide sequence of Zm-A was compared with sequence of rbcL promoter region of a different cultivar of maize (Zea mays L. cv WFG TMS X BS7; Zm-B), the difference rate between two cultivars was 4.3%. The mean of sequence divergence between Zm-A and three grass species in the same tribe, Andropogoneae, in the upstream region from 29 to 420 of ATG was 1.8%, whereas between Zm-B and above-mentioned three species was 5.4%. Therefore, Zm-A seems to evolutionarily closer to three other species in Andropogoneae tribe than Zm-B is.

• Biomolecules & Therapeutics
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• v.24 no.2
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• pp.140-146
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• 2016

Naringenin (NAR) as one of the flavonoids observed in grapefruit has been reported to exhibit an anti-cancer activity. Activating transcription factor 3 (ATF3) is associated with apoptosis in human colon cancer cells. This study was performed to investigate the molecular mechanism by which NAR stimulates ATF3 expression and apoptosis in human colon cancer cells. NAR reduced the cell viability and induced an apoptosis in human colon cancer cells. ATF3 overexpression increased NAR-mediated cleaved PARP, while ATF3 knockdown attenuated the cleavage of PARP by NAR. NAR increased ATF3 expression in both protein and mRNA level, and increased the luciferase activity of ATF3 promoter in a dose-dependent manner. The responsible region for ATF3 transcriptional activation by NAR is located between -317 and -148 of ATF3 promoter. p38 inhibition blocked NAR-mediated ATF3 expression, its promoter activation and apoptosis. The results suggest that NAR induces apoptosis through p38-dependent ATF3 activation in human colon cancer cells.

• BMB Reports
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• v.38 no.2
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• pp.161-166
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• 2005

Functional protein of MB78 bacteriophage having apparent molecular weight of 22 kDa is expressed from 1.7 kb HindIII G fragment. The nucleotide sequence of this fragment showed two open reading frames of 222 and 196 codons in tail-to-tail orientation separated by a 62-nucleotide intercistronic region. The ORF of 22 kDa protein is present in opposite orientation, i.e. in the complementary strand, preceded by a strong ribosomal binding site and a promoter sequence. Another ORF started from the beginning of the fragment whose promoter region and translational start site lies in the 0.45 kb HincII U fragment which is located next to the HindIII G fragment, that has the sequence for DNA bending. 3' end of the fragment has high sequence homology to the EaA and EaI proteins of bacteriophage P22, a close relative of MB78 phage.

• Tuberculosis and Respiratory Diseases
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• v.58 no.6
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• pp.590-599
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• 2005

Object : Cigarette smoking is a major cause of mucus hypersecretion, which is a pathophysiological feature of many inflammatory airway diseases. Mucins, which are an important part of the airway mucus, are synthesized from the Muc gene in airway epithelial cells. However, the signaling pathways for cigarette smoke-induced mucin synthesis are unknown. The aim of this study was to determine the signal pathway for smoking induced Muc5ac gene expression. Methods : A549 cells were cultured and transiently transfected with the Muc5ac promoter fragment. These cells were stimulated with 5% cigarette smoke extract (CSE) alone or with CSE after a pretreatment with various signal transduction pathway inhibitors (AG1478, PD98059 and SB203580). The Muc5ac promoter activity was examined using the luciferase reporter system, and the level of phosphorylated EGFR, ERK1/2, p38 MAPK and JNK were all examined using Western blot analysis. Muc5ac mRNA expression was also examined using reverse transcriptase polymerase chain reactions (RT-PCR). Results : 1. The peak level of luciferase activity of the Muc5ac promoter was observed at 5% concentration and after 3 hours of incubation with the CSE. The level of EGFR phosphorylation and the luciferase activity of the transfected cells caused by the CSE were significantly suppressed by AG1478 or PD98059 (P<0.01). 2. CSE phosphorylated ERK1/2 or p38 MAPK but not JNK. The Muc5ac mRNA expression level was increased by the CSE but that was suppressed by PD98059 or AG1478. 3. The CSE-induced phosphorylation of ERK1/2 was blocked by PD98059 and that of p38 MAPK was blocked by either PD98059 or SB203580. Either PD98059 or SB203580 suppressed the luciferase activity of the transfected cells (P<0.0001). Conclusion : The Muc5ac mRNA expression level was increased by the CSE. The increased CSE-induced transcriptional activity was mediated via EGF receptor activation, which led to ERK1/2 and p38 MAPK phosphorylation.