• Animal cells and systems
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• v.7 no.1
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• pp.81-87
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• 2003

While screening proteins that interact with DnaA protein, the initiator protein for Escherichia coil chromosomal DNA replication, we found a 52-kD sized protein which bound to DnaA protein in a salt-dependent manner. This protein was identified as trigger factor, a ribosome-associated peptidyl-prolyl- cisltrans isomerase with chaperone activity. Trigger factor was overproduced and purified to near homogeneity, and its effect on the function of DnaA protein was examined, Enhanced binding of DnaA protein to DnaA box with no apparent supershift in the gel-shift experiments suggested that trigger factor, by virtue of its chaperone activity, exerts a change on DnaA protein thus increasing its binding affinity for DnaA box.

• Korean Journal of Microbiology
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• v.34 no.4
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• pp.248-253
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• 1998

Bacteriophage N4, a lytic phage specific for Esherichia coli K12 strain encodes single-stranded DNA-binding protein, N4SSB (bacteriophage N4-coded single-stranded DNA-binding protein). N4SSB protein is originally identified as a protein required for N4 DNA replication. N4SSB protein is also required for N4 late transcription, which is catalyzed by E. coli ${\sigma}^{70}$ RNA polymerase. N4 late transcription does not occur until N4SSB protein is synthesized. Recently it is reported that N4SSB protein is essential for N4 DNA recombination. Therefore N 4SSB protein is a multifunctional protein required for N4 DNA replication, late transcription, and N4 DNA recombination. In this study, a variety of mutant N4SSB proteins containing internal deletions or substitutions were constructed to define and characterize domains important for N4 DNA replication, late transcription, and N4 DNA recombination. Test for the ill vivo activity of these mutant N4SSBs for N4 DNA replication, late transcription, and N4 DNA recombination was examined. The results suggest that C-terminal 7 amino acid residues are important for the activity of N4SSB. Three lysine residues, which are contained in this region play important roles on N4SSB activity.

• Proceedings of the Botanical Society of Korea Conference
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• 1996.07a
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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.

• Archives of Pharmacal Research
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• v.21 no.6
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• pp.712-717
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• 1998

The complete nucleotide sequence of the cDNA clone encoding rat skeletal muscle myosin- binding protein H (MyBP-H) was determined and amino acid sequence was deduced from the nucleotide sequence (GenBank accession number AF077338). The full-length cDNA of 1782 base pairs(bp) contains a single open reading frame of 1454 bp encoding a rat MyBP-H protein of the predicted molecular mass 52.7kDa and includes the common consensus 1CA__TG' protein binding motif. The cDNA sequence of rat MyBP-H show 92%, 84% and 41% homology with those of mouse, human and chicken, respectively. The protein contains tandem internal motifs array (-FN III-Ig C2-FN III- Ig C2-) in the C-terminal region which resembles to the immunoglobulin superfamily C2 and fibronectin type III motifs. The amino acid sequence of the C-terminal Ig C2 was highly conserved among MyBPs family and other thick filament binding proteins, suggesting that the C-terminal Ig C2 might play an important role in its function. All proteins belonging to MyBP-H member contains `RKPS` sequence which is assumed to be cAMP- and cGMP-dependent protein kinase A phosphorylation site. Computer analysis of the primary sequence of rat MyBP-H predicted 11 protein kinase C (PKC)phosphorylation site, 7 casein kinase II (CK2) phosphorylation site and 4N-myristoylation site.

• Journal of Life Science
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• v.23 no.4
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• pp.479-486
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• 2013

The DNA-binding protein from starved cells (DPS), originally identified as a DNA binding protein in Escherichia coli, is known to play an important role in DNA protection. The aim of this study was to evaluate the functional roles of DPS in E. coli against various kinds of external stresses by comparing the properties of wild-type E. coli cells and dps knockout mutant E. coli (${\Delta}dps$) cells. Under various stress conditions, we measured the cell growth of the wild-type E. coli and the dps knockout mutant E. coli (${\Delta}dps$) cells using a UV spectrophotometer. The growth rate of the cells was compared to investigate the functional roles of the DPS protein in E. coli. In comparison to the properties of the wild-type E. coli cells, the dps knockout mutant E. coli (${\Delta}dps$) cells showed highly sensitive phenotypes under various stress conditions, such as heat shock, acidic pH, nutrient deficiency, and different concentrations of reactive oxygen species (ROS), suggesting that DPS plays key roles in E. coli in combating diverse external stresses. The DPS DNA-binding protein in E. coli plays crucial roles in bacterial cell growth and in the protection of the cells from environmental stresses by tightly binding and preserving their DNA molecules.

• Proceedings of the Botanical Society of Korea Conference
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• 1999.07a
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• pp.51-56
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• 1999

Plastids, which are organelles unique to plant cells, bear their own genome that is organized into DNA-protein complexes (nucleoids). Regulation of gene expression in the plastid has been extensively investigated because this organelle plays an important role in photosynthesis. Few attempts, however, have been made to characterize the regulation of plastid gene expression at the chromosomal structure, using plastid nucleoids. In this report, we summarize the recent progress in the characterization of DNA-binding proteins in plastids, with special emphasis on CND41, a DNA binding protein, which we recently identified in the choloroplast nucleoids from photomixotrophically cultured tobacco cells. CND41 is a protein of 502 amino acids which consisted of a transit peptide of 120 amino acids and a mature protein of 382 amino acids. The N-terminal of the 'mature' protein has lysine-rich region which is essential for DNA-binding. CNA41 also showed significant identities to some aspartyl proteases. Protease activity of purified CND41 has been recently confirmed and characterized. On the other hand, characterization of accumulation of CND41 both in wild type and transgenic tobacco with reduced amount of CND41 suggests that CND41 is a negative regulator in chloroplast gene expression. Further investigation indicated that gene expression of CND41 is cell-specifically and developmentally regulated as well as sugar-induced expression. The reduction of CND41 expression in transgenic tobacco also brought the stunted plant growth due to the reduced cell length in stem. GA3 treatment on apical meristem reversed the dwarf phenotype in the transformants. Effects of CND41 expression on GA biosynthesis will be discussed.

• BMB Reports
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• v.51 no.3
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• pp.126-133
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• 2018

Hippo signaling plays critical roles in regulation of tissue homeostasis, organ size, and tumorigenesis by inhibiting YES-associated protein (YAP) and PDZ-binding protein TAZ through MST1/2 and LATS1/2 pathway. It is also engaged in cross-talk with various other signaling pathways, including WNT, BMPs, Notch, GPCRs, and Hedgehog to further modulate activities of YAP/TAZ. Because YAP and TAZ are transcriptional coactivators that lack DNA-binding activity, both proteins must interact with DNA-binding transcription factors to regulate target gene's expression. To activate target genes involved in cell proliferation, TEAD family members are major DNA-binding partners of YAP/TAZ. Accordingly, YAP/TAZ were originally classified as oncogenes. However, YAP might also play tumor-suppressing role. For example, YAP can bind to DNA-binding tumor suppressors including RUNXs and p73. Thus, YAP might act either as an oncogene or tumor suppressor depending on its binding partners. Here, we summarize roles of YAP depending on its DNA-binding partners and discuss context-dependent functions of YAP/TAZ.

• The Korean Journal of Physiology and Pharmacology
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• v.2 no.6
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• pp.671-676
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• 1998

In the present study, we first examined whether the changes in the DNA binding activities of the transcription factors, cAMP response element binding protein (CREB) and activator protein-1 (AP-1) mediate the long-term effects of morphine in differentiated SH-SY5Y human neuroblastoma cells. The increases in CREB and AP-1 DNA binding activities were time-dependent up to 6 days of morphine treatment (1, 4, and 6 days). However, the significant reduction in the DNA binding activities of CREB and AP-1 was observed after 10 days of chronic morphine $(10\;{\mu}M)$ administration. Secondly, we examined whether the changes of CREB and AP-1 DNA binding activities could be modulated by dopamine and haloperidol. Dopamine cotreatment moderately increased the levels of the CREB and AP-1 DNA binding activities induced by 10 days of chronic morphine treatment, and haloperidol cotreatment also resulted in a moderate increase of the CREB and AP-1 DNA binding activities. However, dopamine or haloperidol only treatment showed a significant increase or decrease of the CREB and AP-1 DNA binding activities, respectively. In the case of acute morphine treatment, the CREB and AP-1 DNA binding activities were shown to decrease in a time-dependent manner (30, 60, 90, and 120 min). Taken these together, in differentiated SH-SY5Y cells, morphine tolerance seems to involve simultaneous changes of the CREB and AP-1 DNA binding activities. Our data also suggest the possible involvement of haloperidol in prevention or reversal of morphine tolerance at the transcriptional level.

• Journal of Life Science
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• v.6 no.3
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• pp.185-192
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• 1996

Bacteriophage T7 gene 2.5 protein, a single-stranded DNA binding protein, is required for T7 DNA replication, recombination, and repair. T7 gene 2.5 protein has two distinctive domains, DNA binding and C-terminal domain, directly involved in protein-protein interaction. Gene 2.5 protein participates in the DNA replication of Bacteriophage T7, which makes this protein essential for the T7 growth and DNA replication. What gene 2.5 protein makes important at T7 growth and DNA replication is its binding affinity to single-stranded DNA and the protein-protein important at T7 DNA replication proteins which are essential for the T7 DNA synthesis. We have constructed pGST2.5(WT) encoding the wild-type gene 2.5 protein and pGST2.5$\Delta $21C lacking C-terminal 21 amino acid residues. The purified GST-fusion proteins, GST2.5(WT) and GST2.5(WT)$\Delta$21C, were used for whether the carboxyl-terminal domain participates in the protein-protein interactions or not. GST2.5(WT) and GST2.5$\Delta$21C showed the difference in the protein-protein interaction. GST2.5(WT) interacted with T7 DNA polymerase and gene 4 protein, but GST2.5$\Delta$21C did not interact with either protein. Secondly, GST2.5(WT) interacts with gene 4 proteins (helicase/primase) but not GST2.5$\Delta$21C. these results proved the involvement of the carboxyl-terminal domain of gene 2.5 protein in the protein-protein interaction. We clearly conclude that carboxy-terminal domain of gene 2.5 protein is firmly involved in protein-protein interactions in T7 replication proteins.

• Animal cells and systems
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• v.6 no.4
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• pp.311-315
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• 2002

The RAD4 gene is essential for nucleotide excision repair in Saccharomyces cerevisiae. It has been known that the deduced amino acid sequence of Rad4 protein contains three DNA-dependent ATPase/helicase motifs. To determine the biochemical activities and functional role of RAD4 the Rad4 protein was expressed and purified. Immunoblot analysis showed a specific band of 21 kDa, which was well-matched with the size of open reading frame of the RAD4 gene. The purified Rad4 protein had no detectable helicase activity. However, the protein could interact with double stranded oligonucleotides, as judged by mobility shift assay. This result suggests that the Rad4 protein is a DNA binding protein.