• Journal of Microbiology
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• v.33 no.2
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• pp.128-131
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• 1995

Using differential hybridization, we selected the prk gene fortuitously from Schizosaccharomyces pombe homologous to RACK1 of rat which encodes the receptor for activated protein kinase C. The cDNA sequence of prk was determined and its deduced amino acid sequence was 76% homologous to RACK1 and had the feature of trimeric G protein bata subunit. The specific amino acid sequences required for the protein kinase C binding were also present in Prk as in the case of RACK1 protein. From these similarities, we suggest that the Prk is protein kinase C binding protein of S. prombe. The involvement of Prk in signal transduction mediated by protein kinase C remained to be studied.

• Journal of Life Science
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• v.4 no.3
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• pp.119-123
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• 1994

CRP에 의한 DNA bending의 첫 실험은 cAMP, CRP, DNA complex의 gelelectrophoresis에 의해 확인되었다. Bent DNA fragment의 이동은 같은 크기의 linear fragment보다 느리며, EH cAMP, CRP, DNA 결합위치에 따라서 상이한 이동 pattern을 나타낸다. 즉, DNA 단편의 중앙에 CRP binding site가 있을 때는 말단부분에 있을 때보다 이동도가 느리다. benting각의 크기는 일반적으로 안정한 복합체의 형성에 관계하며, 큰 각을 갖는 것이 보다 더 안정된 구조를 형성하여 전사가 촉진되는 것으로 밝혀져 있다. 본고에서는 CRP에 의한 bending과 CRP에 의한 전사조절 관계와 bending의 관계에 대하여 알아보았다.

• International Journal of Industrial Entomology and Biomaterials
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• v.9 no.1
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• pp.123-126
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• 2004

The actin-binding protein profilin cDNA was firstly isolated from the lepidopteran insect, silkworm Bombyx mori. The B. mori profilin cDNA contains an open reading frame of 378 bp encoding 126 amino acid residues and possesses three cysteine residues. The deduced amino acid sequence of the B. mori profilin cDNA showed 80% identity to Apis mellifera profilin and 72% to Drosophila melanogaster profilin. Northern blot analysis showed that B. mori profilin is highly expressed in epidermis and less strongly in silk gland. In addition, Northern blot analysis revealed the presence of B. mori profilin transcripts in all tissues examined, suggesting that B. mori profilin gene is expressed in most, if not all, body tissues.

• Journal of Microbiology and Biotechnology
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• v.26 no.4
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• pp.637-647
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• 2016

Proliferating cell nuclear antigen (PCNA) is a critical eukaryotic replication accessory factor that supports DNA binding in DNA processing, such as DNA replication, repair, and recombination. PCNA consists of three toroidal-shaped monomers that encircle double-stranded DNA. The diverse functions of PCNA may be regulated by its interactions with partner proteins. Many of the PCNA partner proteins generally have a conserved PCNA-interacting peptide (PIP) motif, located at the N- or C- terminal region. The PIP motif forms a 3₁₀ helix that enters into the hydrophobic groove produced by an interdomain-connecting loop, a central loop, and a C-terminal tail in the PCNA. Post-translational modification of PCNA also plays a critical role in regulation of its function and binding partner proteins. Structural and biochemical studies of PCNA-protein will be useful in designing therapeutic agents, as well as estimating the outcome of anticancer drug development. This review summarizes the characterization of eukaryotic PCNA in relation to the protein structures, functions, and modifications, and interaction with proteins.

• Journal of Aquaculture
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• v.17 no.1
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• pp.62-68
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• 2004

A cDNA encoding the masu salmon, Oncorhynchus masou, estrogen receptor $\alpha$ (msER$\alpha$) was cloned from the pituitary gland by polymerase chain reaction (PCR). This cDNA contains an open reading frame encoding 513 amino acid residues, and the calculated molecular weight of this protein is about 56,430 Dalton. The amino acid sequences of the DNA binding and ligand binding domains of msER$\alpha$ showed high homology to those of other fish species (84-100%). Reverse transcription PCR analysis showed that the mRNA level of msER$\alpha$ in the pituitary was slightly higher in estradiol-17$\beta$(E2) injected masu salmon than that of control fish. To test the biological activity of msER$\alpha$, the cDNA was ligated to a mammalian expression vector and transfected into a gonadotrope-derived cell line, L$\beta$T2, with a reporter plasmid including estrogen responsive element. Expression of the reporter protein, luciferase, was E2 and msER$\alpha$-dependent. The masu salmon ER$\alpha$ is structurally conserved among teleost species and functions as a transcriptional activator in the pituitary cells.

• Animal cells and systems
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• v.10 no.1
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• pp.1-6
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• 2006

Previous studies showed that Cdc7 kinase of Schizosaccharomyces pombe phosphorylated the minichromosome maintenance (Mcm) complex efficiently in the presence of spMcm10 protein. The biochemical properties of the phosphorylated Mcm complexes were examined to understand the activation mechanism of the Mcm complex by Cdc7 kinase. The phosphorylation of Mcm complex in the presence of spMcm10 by Cdc7 kinase did not affect the stability of the Mcm complex containing all six subunits, and the changes in the sedimentation properties were not observed after the phosphorylation. The reconstitution of the Mcm complex using the purified proteins showed that the phosphorylation of Mcm2 proteins did not affect the interactions between Mcm proteins. The phosphorylation of the Mcm2-7 complex at the same condition also did not activate the other biochemical activities such as DNA helicase and single stranded (ss) DNA binding activities. On the other hand, spMcm10 protein that was used for the stimulation of Mcm phosphorylation showed single stranded DNA binding activity, and inhibited the DNA helicase activity of the Mcm4/6/7 complex. These inhibitory effects were reduced by the addition of Cdc7 kinase, suggesting that the phosphorylation by Cdc7 kinase decreased the interactions between spMcm10 and the Mcm complex. Taken together, these results suggested that the phosphorylation by Cdc7 kinase alone is not sufficient for the remodeling and the activation of the Mcm complex, and the additional factors or the phosphorylations might be required for the activation of the Mcm complex.

• Proceedings of the Korean Society of Potoscience Conference
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• 2002.06a
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• pp.68-68
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• 2002

• Proceedings of the Zoological Society Korea Conference
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• 2003.08a
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• pp.192.3-192
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• 2003

No Abstract, See Full Text

• Proceedings of the Korean Society of Toxicology Conference
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• 2002.05b
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• pp.1-19
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• 2002

It is well established that the initiating event in chemical carcinogenesis is the binding of reactive carcinogens to DNA. Thus, a number of analytic methods have been developed for determining levels of carcinogen-DNA adducts in humans as a marker of individual exposure and, potentially, of risk for cancer development. In addition, reactive carcinogens also bind to protein suggesting protein adducts can be used as a surrogate for DNA adducts in some situations. We have developed monoclonal and polyclonal antibodies to carcinogen-DNA and protein adductis and highly sensitive ELISA and immunohistochemical assays for determining levels of adducts in human tissues. These studies have demonstrated higher levels of adducts in those with higher exposure as a result of workplace, dietary, chemotherapy, environmental of lifestyle (smoking) exposures. Elevated levels of adducts have been found in lung and liver cancer cases compared to controls. We have also used DNA adducts to determine efficacy of an antiosidant vitamin intervention. DNA adduct studies have demonstrated very different levels of damage in those with similar exposure levels. These interindividual differences are likely the result genetic differences in capacity to activate carcinogens, detoxify reactive intermediates and repair DNA adducts once formed. We are currently investigating the relationship between polymorphisms in a number of these genes to determine their relationship to adduct levels as well as their ability to confer increased risk for cancer development. The ability to identify high risk individuals will allow the targeting of screening and preventive strategies to those most likely to benfit.

• Toxicological Research
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• v.14 no.4
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• pp.525-533
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• 1998

The covalent interactions of toluenediisocyanate (TDI) with macromolecules were investigated both in vitro and in vivo. In vitro incubations of 2,4- and 2,6-TDI with DNA or proteins resulted in dose-dependent formation of TDI-protein and TDI-DNA adducts. TDI-treated DNA was highly resistant to enzymatic digestion and thermal hydrolysis, but was readily hydrolyzed under acidic conditions by releasing its corresponding toluenediamine (TDA), suggesting that TDI caused the crosslinking of DNA. Reaction of TDI with albumin and globin resulted in the formation of several adducts, and some adducts were formed in blood of TDI-treated rats in a dose-dependent fashion. Administration of TDI to rats resulted also in a dose-dependent binding of TDI to hepatic tissue. Levels of TDI-albumin adducts were 10 times higher than those of TDI-globin adducts; the biological half lives of TDI-albumin and TDI-globin adducts were 1.2 and 12.5 days, respectively. Globin adducts were detected up to 28 days after the treatment. Hepatic TDI protein adducts were persistent for a substantial period whereas the levels of hepatic TDI-DNA adduct were decreased rapidly. These results indicate that the isocyanato group of TDI is not readily hydrolyzed under physiological conditions, is transported to other organs, and is bound to DNA and/or proteins without further metabolic activation. As the adducted products degrade in the body, TDA is released and introduced to the liver. TDA may additionally bind to hepatic tissue after metabolic activation. Thus, the toxic effect of TDI exposure is considered to persist during the lifetime of the adducted biological macromolecules.