• Journal of Life Science
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• v.26 no.3
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• pp.282-288
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• 2016

Protein-protein interactions regulate the subcellular localization and function of receptors, enzymes, and cytoskeletal proteins. Proteins containing the postsynaptic density-95/disks large/zonula occludens-1 (PDZ) domain have potential to act as scaffolding proteins and play a pivotal role in various processes, such as synaptic plasticity, neural guidance, and development, as well as in the pathophysiology of many diseases. Multi-PDZ domain protein 1 (MUPP1), which has 13 PDZ domains, has a scaffolding function in the clustering of surface receptors, organization of signaling complexes, and coordination of cytoskeletal dynamics. However, the cellular function of MUPP1 has not been fully elucidated. In the present study, a yeast two-hybrid system was used to identify proteins that interacted with the N-terminal PDZ domain of MUPP1. The results revealed an interaction between MUPP1 and Wdpcp (formerly known as Fritz). Wdpcp was identified as a planar cell polarity (PCP) effector, which is known to have a role in collective cell migration and cilia formation. Wdpcp bound to the PDZ1 domain but not to other PDZ domains of MUPP1. The C-terminal end of Wdpcp was essential for the interaction with MUPP1 in the yeast two-hybrid assay. This interaction was further confirmed in a glutathione S-transferase (GST) pull-down assay. When coexpressed in HEK-293T cells, Wdpcp was coimmunoprecipitated with MUPP1. In addition, MUPP1 colocalized with Wdpcp at the same subcellular region in cells. Collectively, these results suggest that the MUPP1-Wdpcp interaction could modulate actin cytoskeleton dynamics and polarized cell migration.

• Tuberculosis and Respiratory Diseases
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• v.54 no.5
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• pp.485-494
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• 2003

Background : Most previous studies regarding the role of GSTMl and GSTT1 on lung cancer risk have been focused mainly on male smokers. However, epidemiological characteristics, histologic types and risk factors are different in female and male lung cancers, we investigated the association between these genotypes and lung cancer risk in males and females separately. Materials and Methods : The study population consisted of 253 lung cancer (153 males and 100 females) and 243 controls (140 males and 103 females). GSTM1 and GSTT1 genotypes were determined by a multiplex PCR. Results : In the male population, neither GSTM1 nor GSTT1 null genotype showed significant difference between cases and controls. In the female population, the frequencies of GSTM1 null genotype showed no significant difference between cases and controls. However, the frequencies of GSTT1 null genotype was significantly higher in cases (70.3%) than controls (55.3%, odds ratio (OR)=2.18; 95% confidence interval (CI=l.21-3.93). When the female population was stratified by age and smoking status, the ORs for GSTT1 null genotype were significantly higher in subgroups of ${\leq}60$ years (OR=4.82; 95% CI=l.61-14.4) and never-smokers (OR=4.29; 95% CI=1.94-9.48) but not in subgroups of >60 years or smokers. When stratifying the female never-smokers by age, the ORs for GSTT1 null genotype were significantly higher in both age groups of ${\leq}60$ years (OR=7.64; 95% CI=2.00-29.2) and >60 years (OR=2.89; 95% CI=1.05-7.94). Conclusion : We found that GSTT1 null genotype was associated with an increased risk of lung cancer in Korean female never-smokers. This result suggests that GSTT1 null genotype could be used as a biomarker for genetic susceptibility to lung cancer in Korean female never-smokers.

• Journal of Life Science
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• v.17 no.7 s.87
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• pp.889-895
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• 2007

A conventional kinesin, KIF5/kinesin-I, is composed of two kinesin heavy chains (KHCs) and two kinesin light chains (KLCs) and binds directly to microtubules. KIF5 motor mediates the transport of various membranous organelles, but the mechanism how they recognize and bind to a specific cargo has not yet been completely elucidated. Here, we used the yeast two-hybrid system to identify the neuronal protein(s) that interacts with the tetratricopeptide repeats (TRP) of KLCI and found a specific interaction with JNK/stress-activated protein kinase-associated protein 1 (JSAP1/JIPP3). The yeast two-hybrid assay demonstrated that the TRP 1,2 domain-containing region of KLCI mediated binding to the leucine zipper domain of JSAP1. JSAP1 also bound to the TRP region of lac2 but not to neuronal KIF5A, KIF5C and ubiquitous KIF5B in the yeast two-hybrid assay. In addition, these proteins showed specific interactions in the GST pull-down assay and by co-immunoprecipitation. KLCI and KIF5B interacted with GST-ISAP1 fusion proteins, but not with GST alone. An antibody to JSAPI specifically co-immunoprecipitated KIF5s associated with JSAP1 from mouse brain extracts. These results suggest that JSAP1, as KLC1 receptor, is involved in the KIF5 mediated transport.

• Journal of Life Science
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• v.33 no.11
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• pp.868-875
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• 2023

Kinesin-1 is a motor protein identified as the first member of the kinesin superfamily (KIF), which plays a role in intracellular cargo transport by acting as microtubule-dependent motor proteins within cells. Kinesin-1 consists of two heavy chains (KHCs, also known as KIF5s) and two light chains (KLCs). The 93 amino acids in the carboxyl (C)-terminal tail region of KIF5A are not homologous to the C-terminal tail region of KIF5B or the C-terminal tail region of KIF5C. In this study, we used a yeast two-hybrid screen to identify the binding proteins that interacted with the C-terminal region of KIF5A. We found an association between KIF5A and CUE domain containing 2 (CUEDC2), which is proposed to function as an adaptor protein involved in ubiquitination pathways and protein trafficking. CUEDC2 bound to the C-terminal region of KIF5A and did not interact with KIF5B (the motor of kinesin-1), KIF3A (the motor of kinesin-2), or kinesin light chain 1 (KLC1). KIF5A specifically bound to the C-terminal region of CUEDC2. Furthermore, KIF5A did not interact with another isoform: CUEDC1. In addition, glutathione S-transferase (GST) pull-downs showed that KIF5A directly bound GST-CUEDC2 but did not interact with GST-CUEDC1 and GST alone. When myc-KIF5A and EGFP-CUEDC2 were co-expressed in HEK-293T cells, CUEDC2 co-immunoprecipitated with kinesin-1, and myc-KIF5A and FLAG-CUEDC2 colocalized in the cells. These results suggest that in intracellular cargo transport by kinesin-1, CUEDC2 serves as an adaptor protein connecting kinesin-1 and cargo by binding to KIF5A.

• Journal of Food Hygiene and Safety
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• v.16 no.3
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• pp.212-220
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• 2001

To investigate the modifying effect of Kwao Kreu, Pueraria mirifica (PM), we performed two kind of studies which are the non-surgical medium-term carcinogenicity study and the modulation of gap junctional intercellular communication study. The first study, a non-surgical medium-term carcinogenicity bioassay was done to investigate the modifying effect of Kwao Keru, Pueyaria mirifca (PH), a rejuvenating folk medicine from Thailand, on the male F344 rat liver. Specific pathogen free, male 6-week-old F3444 rats were divided into ten groups. To induce hepatocarcinogenesis, those in all groups were given a single i.p. injection of DEN (200 mg/kg) and were received two i.p. injection of DGA (300 mg/kg) at the ends of weeks 2 and 5. Rats of group 3-6 were given sodium phenobarbital (PB 0.05% in drink). A diet containing 10 mg/kg PM was given to group 2 during the post-initiation phase and to groups 4 and 5 during promotion and initiation phase, respectively. Group 6 was given the experimental diet alone throughout the experiment (8 weeks). Rats of group 7, 8, 9 and 10 were fed 1000 mg/kg PH in the same manner as group 2, 4, 5 and 6. All animals were sacrificed at 8 weeks after DEN administration. Result of the immunohistochemical staining of the glutathione S-transferase placental form (GST-p) indicated that the numbers and areas of the preneoplastic leisions were not significantly changed in all PM treatment group comparing to control group. Also the numbers and areas of GST-p positive foci among group 7, 8, 9 and 10 were not significantly changed in comparing to control group. To study the effect of PM on the modulation of gap junctional intercellular communication, the present study was performed scrape-loading dye transfer (SL/DT) assay in human keratinocytes. The results showed that PM could not modulate GJIC. These results indicate that Pueraria mirifica may have no carcinogenic effects on experimental hepatocarcinogenesis in rats and gap junctional intercellular communication in human keratinocyte.

• Korean Journal of Food Science and Technology
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• v.46 no.5
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• pp.641-647
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• 2014

In this study, we evaluated the effect of Capsosiphon fulvescens extract (CFE) and its active compound, pheophorbide A (PhA), on diabetic kidney failure. Diabetes mellitus (DM) was induced by a single intraperitoneal injection of streptozotocin (STZ; 40 mg/kg body weight (BW)). After a week, the rats were orally administered CFE (4 and 20 mg/kg BW) or PhA (0.2 mg/kg BW) once a day for 9 weeks. After scarification, renal tissue samples were collected for biochemical and histochemical analyses. Our study showed that the treatment with CFE and PhA significantly decreased lipid peroxidation level and the activities of glutathione peroxidase and glutathione-S-transferase (p<0.05), but it increased glutathione level and the activities of glutathione reductase, superoxide dismutase, and catalase in the renal tissues (p<0.05). The CFE- and PhA-treated rats with DM showed improved histochemical appearance and decreased abnormal glycogen accumulation. Therefore, we suggest that PhA-containing CFE could exert renal protective effects against STZ-induced oxidative stress.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.5
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• pp.782-787
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• 2002

This study was done to investigate the effects of Korean mistletoe water extract and lectin on the apoptosis and preneoplastic lesion in chemically induced rat hepatocarcinogenesis. To attain the above objectives, weanling Sprague-Dawley male rats were fed modified AIN-76 diets containing 10% corn oil for 9 weeks. One week after feeding starts, rats were intraperitoneally injected twice with a dose of diethylnitrosamine (DEN, 50 mg/kg body weight (BW). Rats were provided with 0.05% phenobarbital (PB) in drinking water from one week after DEN treatment until the end of experiment. During the period of PB treatment, rats were injected with mistletoe extract (100 $\mu\textrm{g}$/kg BW) and lectin (10 $\mu\textrm{g}$/kg BW) twice a week. At the end of 9th week, rats were sacrificed and the formation of hepatic glutathione S-transferase placental form positive (GST-P$^{+}$) foci, apoptosis, DNA fragmentation and apoptosis related proteins were determined respectively. The formation of GST-P$^{+}$foci was significantly decreased by mistletoe extract or lectin treatment. Although there was no effect on apoptosis and DNA fragmentation in hepatic tissue by mistletoe extract or lectin treatment, caspase-9 and fas-L were increased. These results suggest that Korean mistletoe extract and lectin have a potential to inhibit hepatocarcinogenesis by increasing apoptosis.sis.

• Journal of the East Asian Society of Dietary Life
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• v.24 no.6
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• pp.759-767
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• 2014

This study examined the effect of Momordica charantia L. (bitter melon: BM) on lipid and hepatic antioxidative enzyme levels in diabetic rats. Diabetes mellitus was induced in male Sprague-Dawley rats by injection of streptozotocin (STZ), and rats were fed for 4 weeks with experimental groups divided into four groups: a normal control group, STZ-control and STZ-BM 5% & STZ-BM 10% treated groups. Levels of free fatty acids (FFA), high-density lipoprotein cholesterol (HDL-chol), triglycerides (TG) in plasma and malondialdehyde (MDA) & protein in liver, catalase (CAT), superoxide dismutase (SOD), glutathione-S-transferase (GST), and xanthine oxidase (XOD) were measured in liver cytosol. Level of HDL-chol significantly increased in the STZ-BM 5% diabetic group. TG & FFA levels were significantly higher in all diabetic groups compared to the control group. MDA and protein levels were significantly higher in the STZ-BM 5% group compared to all other experimental group. CAT level was higher in the supplementary group with BM compared to the STZ-control group, although the difference was not significantly different. SOD level was not significant in any experimental groups. GST level was significantly higher in the BM-treated groups compared to the STZ-control group. XOD level was significantly lower in the BM 5% group and significantly decreased in all experimental groups. These results show that supplementation of BM fruit powder may have beneficial effects on diabetic complications and damage caused by oxidative stress.

• Journal of Food Hygiene and Safety
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• v.16 no.4
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• pp.349-354
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• 2001

Oxidative stress is believed to play an important role in the development of vascular complications associated with diabetes mellitus. We examined the antioxidative effect of sesamin and sesamolin on the preventing the development of insulin dependent diabetes mellitus using streptozotocin-induced Spraque Dawley diabetic rats. From 48 hours after injection of streptozotocin (60 mg/kg body weight), a portion of diabetic rats were fed with 0.2% sesamin and sesamolin containing diet for 3 weeks. There were significant differences of blood glucose and kidney weight between diabetic ports and control. Sesamin and sesamolin increased glutathione-S-transferase activity in kidney. The concentration of the thiobarbituric acid-reactive substances in the serum, liver, and kidney of diabetic rats administered sesamin and sesamolin decreased significantly as compared with that of the non-treated diabetic group. Dietary sesamin and sesamolin suppressed the oxidative stress in the diabetic rats. These results demonstrated that sesamin and sesamolin are potential and effective antioxidants that can protect the complications associated with diabetes.

• Parasites, Hosts and Diseases
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• v.56 no.2
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• pp.135-145
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• 2018

Due to the critical location and physiological activities of the retinal pigment epithelial (RPE) cell, it is constantly subjected to contact with various infectious agents and inflammatory mediators. However, little is known about the signaling events in RPE involved in Toxoplasma gondii infection and development. The aim of the study is to screen the host mRNA transcriptional change of 3 inflammation-related gene categories, PI3K/Akt pathway regulatory components, blood vessel development factors and ROS regulators, to prove that PI3K/Akt or mTOR signaling pathway play an essential role in regulating the selected inflammation-related genes. The selected genes include PH domain and leucine- rich-repeat protein phosphatases (PHLPP), casein kinase2 (CK2), vascular endothelial growth factor (VEGF), pigment epithelium-derived factor (PEDF), glutamate-cysteine ligase (GCL), glutathione S-transferase (GST), and NAD(P)H: quinone oxidoreductase (NQO1). Using reverse transcription polymerase chain reaction (RT-PCR) and quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR), we found that T. gondii up-regulates PHLPP2, $CK2{\beta}$, VEGF, GCL, GST and NQO1 gene expression levels, but down-regulates PHLPP1 and PEDF mRNA transcription levels. PI3K inhibition and mTOR inhibition by specific inhibitors showed that most of these host gene expression patterns were due to activation of PI3K/Akt or mTOR pathways with some exceptional cases. Taken together, our results reveal a new molecular mechanism of these gene expression change dependent on PI3K/Akt or mTOR pathways and highlight more systematical insight of how an intracellular T. gondii can manipulate host genes to avoid host defense.