• Preventive Nutrition and Food Science
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• 제4권2호
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• pp.139-144
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• 1999

Lipoprotein lipase (LPL) I san enzyme that catalyzed the hydrolysis of triacylglycerols of chylomicrons and VLDL to produce 20acylglycerols and fatty acids. The enzyme, LPL, is localized on the surface of the capillary endothelium and is widely distributed in extrahepatic tissues including heart, skeletal muscle and adipose tissue. LPL has been isolated from boving milk by affinity chromatography on heparin-separose in 2 M NaCL, 5mM barbital buffer, pH 7.4. To elucidate the lipid-binding regin, LPL was digested with trypsin and then separated by gel filtration. Lipid binding region of LPL has been investigated by recombining LPL peptides with DMPC vesicles. Proteolytic LPL fragments with DMPC were reassembled and stabilized by cholate. Lipid-binding region of LPL was identified by a PTH-automated protein sequencer, as AQQHYPVSAGYTK. The analysis of the secondary structure of the lipid-binding peptides revealed a higher probability of $\alpha$-helix structure compared to the whole LPL protein. The prediction of hydrophobicity of lipid -binding region was highly hydrophobic (-1.1) compared to LPL polypetide(-0.4).

• Biomolecules & Therapeutics
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• 제4권1호
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• pp.97-102
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• 1996

To investigate whether human $\beta$$_2$-adrenergic receptor devoid of the C-terminal two transmembrane helices retain its ligand binding activity and specificity, 5'780-bp DNA fragment of the receptor gene which encodes amino acid 1-260 of human $\beta$$_2$-adrenergic receptor was subcloned into the bacterial fusion protein expression vector and expressed as a form of glutathione-S-transferase (GST) fusion protein in E. coli DH5$\alpha$. The receptor fusion protein was expressed as a membrane bound form which was verified by SDS-PAGE and Western blot. The fusion protein expressed in this study specifically bound $\beta$-adrenergic receptor ligand [$^3$H] Dihydroalprenolol. In saturation ligand binding assay, the $K_{d}$ value was 7.6 nM which was similar to that of intact $\beta$$_2$-adrenergic receptor in normal animal tissue ( $K_{d}$=1~2 nM) and the $B_{max}$ value was 266 fmol/mg membrane protein. In competition binding assay, the order of binding affinity of various adrenergic receptor agonists to the fusion protein was isoproterenol》epinephrine norepinephrine, which was similar to that of intact receptor in normal animal tissue. These results suggest that N-terminal five transmembrane helices of the $\beta$$_2$-adrenergic receptor be sufficient to determine the ligand binding activity and specificity, irrespective of the presence or absence of the C-terminal two transmembrane helices.s.s.s.

• 대한의생명과학회지
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• 제18권3호
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• pp.227-236
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• 2012

Previous study showed that swimming improved obesity but was not through $PPAR{\alpha}$ activation in liver and skeletal muscle in high fat diet-fed female mice with functioning ovaries as an animal model of obese premenopausal women. Thus, this study was aimed at investigation of the effects of swimming on the promotion of health and its molecular mechanism in adipose tissue of high fat diet-fed female mice. Eight-week-old female C57BL/6J mice were randomly divided into two groups (a non-swim control group and a swim group, n=8/group). Mice in the swim group swam for 2 h daily for 6 weeks in water bath with temperature of $35{\pm}1^{\circ}C$. All the animals received high fat diet (45% kcal fat) for 6 weeks. Reverse transcription-polymerase chain reaction was used to elucidate the molecular mechanism. Female mice subjected to swimming had significantly decreased body weight gain and white adipose tissue mass compared with the female control mice. Histological studies illustrated that swimming decreases the hepatic lipid accumulation. As expected, swimming did not affect the expression of mRNA levels of peroxisome proliferator-activated receptor (PPAR) ${\alpha}$ and $PPAR{\alpha}$ target genes responsible for mitochondrial fatty acid ${\beta}$-oxidation, such as carnitine palmitoyltransgerase-1 and medium chain acyl-CoA dehydrogenase in the white adipose tissue. However, mice that underwent 6-weeks of swimming exercise had decreased the mRNA expression of lipogenic genes, such as sterol regulatory element-binding proteins-1C and fatty acid synthase in comparison to sedentary control mice, with decreased $PPAR{\gamma}$ target genes involved in adipocyte-specific marker genes, such as adipocyte fatty acid binding protein and leptin in the white adipose tissue. These results suggest that swimming can effectively prevent obesity induced by high fat diet-fed, in part through down-regulation of adipogenesis and lipogenesis in white adipose tissue of female obese mice. Moreover, these results suggest that swimming maybe contributing the promotion of health through regulation of adipogenesis and lipogenesis in overweight premenopausal women.

• BMB Reports
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• 제51권3호
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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.

• Clinical and Experimental Reproductive Medicine
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• 제16권2호
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• pp.131-138
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• 1989

The present study was designed to develop a new method for the determination of estrogen receptor in porcine uterus using frozen sections. Cryostat sections were incubated with $^3H$-estradiol($^3H$-$E_2$) in the presence or absence of diethylstilbestrol(DES) and the radioactivity of 3H-E2 bound to estrogen receptor(ER) was detected. The level of specific estrogen receptor was determined by Scatchard analysis. The highest ratio of specific binding against total binding was achieved in 3 sec. tions(5mm x 5mm) which was corresponded to lOO${\mu}$/ml protein concentration. Optimal binding was obtained during incubation with $^3H$-$E_2$ for 30 minutes at 23$^{\circ}C$ after treatment of sections with acetone for 20 seconds. Three time-washing of sections was proved to be appropriate for the removal of unbound 3H-E2. 200-fold molar excess of DES was substituted for the binding of $^3H$-$E_2$ to ER sufficiently(binding efficiency of 54.8%). ER was saturated with 4nM of $^3H$-$E_2$ and its dissociation constant was 0.1nM. ER assay using frozen sections(Histological radioreceptor assay, HRRA) was significantly correlated with radioreceptor assay for estradiol(RRA, 0.976 , p

• Asian Pacific Journal of Cancer Prevention
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• 제14권11호
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• pp.6803-6806
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• 2013

Background: Interferon regulatory factor 6 (IRF6) is a transcription factor with distinct and conserved DNA and protein binding domains. Mutations within the protein binding domain have been significantly observed in subjects with orofacial cleft relative to healthy controls. In addition, recent studies have identified loss of expression of IRF6 due to promoter hypermethylation in cutaneous squamous cell carcinomas. Since mutational events occurring within the conserved domains are likely to affect the function of a protein, we investigated whether regions within the IRF6 gene that encodes for the conserved protein binding domain carried mutations in oral squamous cell carcinoma (OSCC). Materials and Methods: Total chromosomal DNA extracted from 32 post surgical OSCC tissue samples were amplified using intronic primers flanking the exon 7 of IRF6 gene, which encodes for the major region of protein binding domain. The PCR amplicons from all the samples were subsequently resolved in a 1.2% agarose gel, purified and subjected to direct sequencing to screen for mutations. Results: Sequencing analysis resulted in the identification of a mutation within exon 7 of IRF6 that occurred in heterozygous condition in 9% (3/32) of OSCC samples. The wild type codon TTC at position 252 coding for phenylalanine was found to be mutated to TAC that coded for tyrosine (F252Y). Conclusions: The present study identified for the first time a novel mutation within the conserved protein binding domain of IRF6 gene in tissue samples of subjects with OSCC.

• 한국발생생물학회지:발생과생식
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• 제22권4호
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• pp.351-360
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• 2018

The adipogenesis is a maturation process of pre-adipocyte cell into mature lipid-filled adipocyte cell. The adipogenesis begins at the late prenatal stage and continues until the early postnatal age. Because the adipogenesis and formation of adipose tissue persist during postnatal period and are precisely regulated by the action of numerous gene products, the present research was attempted to determine the expressional patterns of adipose tissue-associated genes in the rat epididymal fat pad at different postnatal ages, from 7 days to 2 years of ages, using a quantitative real-time PCR analysis. The basal expression levels of CCAAT/enhancer binding protein gamma, sterol regulatory element binding transcription factor 1, fatty acid binding protein 4, adiponectin, leptin, and resistin at the early postnatal ages were significantly lower than those at the elderly ages, even though a fluctuation of expressional levels was observed at some ages. The lowest expressional level of delta like non-canonical Notch ligand 1 was detected at 44 days and 5 months of ages. The expression of peroxisome proliferator-activated receptor gamma ($PPAR{\gamma}$) was the highest at 44 days of age, followed by a diminished expression of $PPAR{\gamma}$ at the elderly ages. These results indicate the existence of a complex regulatory mechanism(s) for expression of adipose tissueassociated genes in the rat epididymal fat during postnatal period.

• BMB Reports
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• 제34권2호
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• pp.95-101
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• 2001

Tissue transglutaminase (TGII, $G{\alpha}h$) belongs to a family of enzymes which catalyze post-translational modification of proteins by forming isopeptides via $Ca^{2+}$-dependent reaction. Although TGII-mediated formation of isopeptides has been implicated to play a role in a variety of cellular processes, the physiological function of TGII remains unclear. In addition to this Tease activity, TGII is a guanosine triphosphatase (GTPase) which binds and hydrolyzes GTP It is now well recognized that the GTPase action of TGII regulates a receptor-mediated transmembrane signaling, functioning as a signal transducer of the receptor. This TGII function signifies that TGII is a new class of GTP-binding regulatory protein (G-protein) that differs from "Classical" heterotrimeric G-proteins. Regulation of enzyme is an important biological process for maintaining cell integrity. This review summarizes the recent development in regulation of TGII that may help for the better understanding of this unique enzyme. Since activation and inactivation of GTPase of TGII are similar to the heterotrimeric G-proteins, the regulation of heterotrimeric G-protein in the transmembrane signaling is also discussed.

• Biomolecules & Therapeutics
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• 제22권6호
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• pp.497-502
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• 2014

In the present study, we found that the natural compound arctigenin inhibited hydrogen peroxide-induced reactive oxygen species (ROS) production in rat primary astrocytes. Since hemeoxygenase-1 (HO-1) plays a critical role as an antioxidant defense factor in the brain, we examined the effect of arctigenin on HO-1 expression in rat primary astrocytes. We found that arctigenin increased HO-1 mRNA and protein levels. Arctigenin also increases the nuclear translocation and DNA binding of Nrf2/c-Jun to the antioxidant response element (ARE) on HO-1 promoter. In addition, arctigenin increased ARE-mediated transcriptional activities in rat primary astrocytes. Further mechanistic studies revealed that arctigenin increased the phosphorylation of AKT, a downstream substrate of phosphatidylinositol 3-kinase (PI3K). Treatment of cells with a PI3K-specific inhibitor, LY294002, suppressed the HO-1 expression, Nrf2 DNA binding and ARE-mediated transcriptional activities in arctigenin-treated astrocyte cells. The results collectively suggest that PI3K/AKT signaling pathway is at least partly involved in HO-1 expression by arctigenin via modulation of Nrf2/ARE axis in rat primary astrocytes.

• Current Research on Agriculture and Life Sciences
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• 제32권3호
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• pp.149-154
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• 2014

1. Pepsin과 pancreatin 소화물들을 비교한 결과, 순수한 팥 단백질 중에서 소화효소 저항성을 가지는 단백질이 존재하는 것으로 확인되었다. 2. 팥의 주요 단백질을 제거하고 pepsin과 pancreatin으로 소화시켰을 때 더 많은 분해가 일어나는 것으로 보아 팥의 주요단백질들 중에 소화효소 저항성을 가지는 것이 많을 것이라 추측된다. 3. 팥의 주요 단백질들은 장 점막세포와는 크게 작용하지 않는 것을 확인할 수 있었다. 4. 팥 단백질의 데이터베이스 구축과 팥 단백질이 다른 영양소들과의 상호작용을 하는 지에 대한 연구가 진행되어야 할 것이다.