Hye-Jin Park

Transcriptional Activity of Sp1 Is Regulated by Molecular Interactions between the Zinc Finger DNA Binding Domain and the Inhibitory Domain with Corepressors, and This Interaction Is Modulated by MEK

Sp1 activates the transcription of many cellular and viral genes with the GC-box in either the proximal promoter or the enhancer. Sp1 is composed of several functional domains, such as the inhibitory domain (ID), two serine/threonine-rich domains, two glutamine-rich domains, three C2H2-type zinc finger DNA binding domains (ZFDBD), and a C-terminal D domain. The ZDDBD is the most highly conserved domain among the Sp-family transcription factors and plays a critical role in GC-box recognition. In this study, we investigated the protein-protein interactions occurring at the Sp1ZFDBD and the Sp1ID, and the molecular mechanisms controlling the interaction. Our results found that Sp1ZFDBD and Sp1ID repressed transcription once they were targeted to the proximal promoter of the pGal4 UAS reporter fusion gene system, suggesting molecular interaction with the repressor molecules. Indeed, mammalian two-hybrid assays, GST fusion protein pull-down assays, and co-immunoprecipitation assays showed that Sp1ZFDBD and Sp1ID are able to interact with corepressor proteins such as SMRT, NcoR, and BCoR. The molecular interactions appear to be regulated by MAP kinase/Erk kinase kinase (MEK). The molecular interactions between Sp1ID and the corepressor might explain the role of Sp1 as a repressor under certain circumstances. The siRNA-induced degradation of the corepressors resulted in an up-regulation of Sp1-dependent transcription. The cellular context of the corepressors and the regulation of molecular interaction between corepressors and Sp1ZFDBD or Sp1ID might be important in controlling Sp1 activity.

Proto-oncogene FBI-1 (Pokemon) and SREBP-1 Synergistically Activate Transcription of Fatty-acid Synthase Gene (FASN)

FBI-1 (Pokemon/ZBTB7A) is a proto-oncogenic transcription factor of the BTB/POZ (bric-à-brac, tramtrack, and broad complex and pox virus zinc finger) domain family. Recent evidence suggested that FBI-1 might be involved in adipogenic gene expression. Coincidentally, expression of FBI-1 and fatty-acid synthase (FASN) genes are often increased in cancer and immortalized cells. Both FBI-1 and FASN are important in cancer cell proliferation. SREBP-1 is a major regulator of many adipogenic genes, and FBI-1 and SREBP-1 (sterol-responsive element (SRE)-binding protein 1) interact with each other directly via their DNA binding domains. FBI-1 enhanced the transcriptional activation of SREBP-1 on responsive promoters, pGL2-6x(SRE)-Luc and FASN gene. FBI-1 and SREBP-1 synergistically activate transcription of the FASN gene by acting on the proximal GC-box and SRE/E-box. FBI-1, Sp1, and SREBP-1 can bind to all three SRE, GC-box, and SRE/E-box. Binding competition among the three transcription factors on the GC-box and SRE/E-box appears important in the transcription regulation. FBI-1 is apparently changing the binding pattern of Sp1 and SREBP-1 on the two elements in the presence of induced SREBP-1 and drives more Sp1 binding to the proximal promoter with less of an effect on SREBP-1 binding. The changes induced by FBI-1 appear critical in the synergistic transcription activation. The molecular mechanism revealed provides insight into how proto-oncogene FBI-1 may attack the cellular regulatory mechanism of FASN gene expression to provide more phospholipid membrane components needed for rapid cancer cell proliferation.

FBI-1 Enhances Transcription of the Nuclear Factor-κB (NF-κB)-responsive E-selectin Gene by Nuclear Localization of the p65 Subunit of NF-κB

The POZ domain is a highly conserved protein-protein interaction motif found in many regulatory proteins. Nuclear factor-κB (NF-κB) plays a key role in the expression of a variety of genes in response to infection, inflammation, and stressful conditions. We found that the POZ domain of FBI-1 (factor that binds to the inducer of short transcripts of human immunodeficiency virus-1) interacted with the Rel homology domain of the p65 subunit of NF-κB in both in vivo and in vitro protein-protein interaction assays. FBI-1 enhanced NF-κB-mediated transcription of E-selectin genes in HeLa cells upon phorbol 12-myristate 13-acetate stimulation and overcame gene repression by IκBα or IκBβ. In contrast, the POZ domain of FBI-1, which is a dominant-negative form of FBI-1, repressed NF-κB-mediated transcription, and the repression was cooperative with IκBα or IκBβ. In contrast, the POZ domain tagged with a nuclear localization sequence polypeptide of FBI-1 enhanced NF-κB-responsive gene transcription, suggesting that the molecular interaction between the POZ domain and the Rel homology domain of p65 and the nuclear localization by the nuclear localization sequence are important in the transcription enhancement mediated by FBI-1. Confocal microscopy showed that FBI-1 increased NF-κB movement into the nucleus and increased the stability of NF-κB in the nucleus, which enhanced NF-κB-mediated transcription of the E-selectin gene. FBI-1 also interacted with IκBα and IκBβ.

Effects of Korean Red Ginseng Extract for the Treatment of Atopic Dermatitis-Like Skin Lesions in Mice

Atopic dermatitis (AD) is an allergic, inflammatory skin disease characterized by chronic eczema and mechanical injury to the skin, caused by scratching. Korean red ginseng (RG) has diverse biological activities, but the molecular effects of RG on allergic diseases, like AD, are unclear. The present study was designed to investigate whether RG inhibits 1-chloro-2,4-dinitrobenzene (DNCB)-induced AD in a mouse model. DNCB was applied topically on the dorsal surface of Balb/c mice to induce AD-like skin lesions. We observed the scratching behavior and examined the serum IgE level and interleukin (IL)-4 and IL-10 in splenocytes compared with dexamethasone. We also evaluated the DNCB-induced mitogen-activated protein kinases (MAPKs), NF-κB, and Ikaros activities after RG treatment using reverse transcriptase-polymerase chain reaction, Western blotting, and ELISA. Our data showed that the topical application of RG significantly improved the AD-like skin lesions and scratching behavior. RG decreased not only the mRNA expression of IL-4 and IL-10, but also the secretion of IL-4 protein and serum IgE in mice. Additionally, RG treatment decreased the DNCB-induced MAPKs activity and subsequent Ikaros translocation irrespective of NF-κB. We suggest that RG may be useful as a therapeutic nutrition for the treatment of AD.

Inhibitory Effects of Various Mulberry Fruits (Morus alba L.) on Related Enzymes to Adult Disease

The objective of this research was to develop the functional material of water and 60% ethanol extracts from nine kinds of mulberry fruits (Morus alba L.) that influence the inhibitory activity on angiotensin-converting enzyme, xanthine oxidase, α-amylase, and α-glucosidase. The total phenolic contents in the water extracts were over 2 mg/g in two species (Cheongilppong and Kangwon Ⅲ) and five species (Daeyoupchosaeng, Cheongilppong, Kangwon Ⅲ, Hihak, and Cataneo) of 60% ethanol extracts. The inhibitory activity against the angiotensin-converting enzyme was determined with them. Baekwoon Ⅲ was 90.9±4.5% in the water extracts, and Hihak was 81.8±4.5% in the 60% ethanol extracts. The inhibitory activity of Kuksang 20 against xanthin oxidase was about 10% in the water extracts, and Cataneo was 21.4±2.3% in the 60% ethanol extracts. Six of the species (Daeyoupchosaeng, Suwonppong, Cheongilppong, Kangwon Ⅲ, Hihak, and Kuksang 20) in the water extracts showed inhibitory activities against α-amylase, as 100%, respectively. The inhibitory activity of α-glucosidase was determined for these nine species. Four species (Baekwoon Ⅲ, Daeyoupchosaeng, Cheongilppong, Kangwon Ⅲ, Hihak, and Kuksang 20) in the water extracts and three species (Daechoukmyeun, Kangwon Ⅲ, and Kuksang 20) in the 60% ethanol extracts showed inhibition of over 20%. The results revealed strong biological activity in spite of little total phenolic contents. These water and 60% ethanol extracts with high-quality biological activity from various mulberry fruits (Morus alba L.) are expected to represent good candidates for the development of antihypertentive and antidiabetes sources.

Coregistration of small animal PET and autoradiography for in vivo-ex vivo comparison

Non-invasive imaging of small animal and its quantification techniques are needed to be evaluated by comparison with ex vivo image. To overcome the existing method, hand-operated comparison with the unaided eye observation, we present an algorithm that matches the target area in PET scanned in vivo with an autoradiography image acquired ex vivo. We applied a coregistration algorithm that uses voxel similarity to find the corresponding slices and to make quantitative measurements. Automatic matching of in vivo and ex vivo images is novel, and can provide better validation than manual matching techniques.

3D Gesture-Based View Manipulator for Large Scale Entity Model Review

Hand gesture-based Human Computer Interaction (HCI) is one of the most natural and intuitive methods of communication between humans and machines because it closely mimics how humans interact with each other. Its intuitiveness and naturalness are needed to explore extensive and complex data or virtual realities. We developed a 3D gesture interface to manipulate the display of a 3D entity model. For gesture recognition, we use the Kinect as a depth sensor to acquire depth image frames. We track the position of the user’s skeleton in each frame and detect preset gestures. By simple gestures, the user can pan, zoom, rotate, and reset the view and freely navigate inside the 3D entity model in the virtual space. The proposed gesture interface is integrated with the stereoscopic 3D model viewer that we have previously developed for 3D model review.

Stereoscopic 3D Model Viewer with Improved Depth Perception for Battlefield Visualization

We developed a stereoscopic 3D model viewer and constructed a prototype visualization system to provide an overview of the battlefield as well as the detailed view of a user-selected entity. For the overview of the battlefield, a battlefield visualization software, the SIMDIS, is used. The user is allowed to select an entity on the overview screen; the detailed view of this entity is displayed in the 3D model viewer. In order to provide the user appropriate depth perception under the condition of user movement, the distance of the screen from the user, which is one of the stereo parameters used in the 3D model viewer, is required to be set correctly. In order to update this parameter while the user is moving, we employed a depth camera and applied a real-time head tracking method to the acquired depth image frames. In the implemented system, we used a 2D display and a 3D TV to show the overview of the battlefield by the SIMDIS and the stereoscopic 3D model viewer, respectively.

Brewing and Quality Characteristics of New Grape Cultivar 'Okrang' Wine in Fermentation Process

This study was carried out to investigate the effects of cold maceration and heat treatment prior to alcohol fermentation on the quality characteristics of wine made from Okrang grape cultivar. The results of this study show that alcohol contents of wines increased as fermentation period increased, whereas °Brix values decreased. The pH levels of wines ranged from 3.17 to 3.42 while the total acidities of wines ranged from 0.49∼0.99%. The free sugar contents of wines tended to decrease as fermentation period increased. In particular, free sugar content of wine pre-treated at low temperature prior to alcohol fermentation slowly. Total polyphenol content of wine heat-treated prior to alcohol fermentation was higher than those of other wines and reached a maximum value after fermentation for 2 days. Campbell Early wine showed the strongest antioxidant effect, measured based on DPPH free radical scavenging activity, followed by Okrang wine pressing after fermentation. These results indicate that pre-treatment before wine fermentation greatly affects wine quality and biofunctional activities.

Anti-inflammatory Effect of Myricetin from Rhododendron mucronulatum Turcz. Flowers in Lipopolysaccharide-stimulated Raw 264.7 Cells

As a research of inflammation inhibitory activity using natural resource, the inflammation inhibitory activity by purified active compound from Rhododendron mucronulatum flower was experimented. Rhododendron mucronulatum flower components were purified and separated with Sephadex LH-20 and MCI gel CHP-20 column chromatography, Purified compound was confirmed as myricetin by 1HNMR, 13C-NMR and Fast atom bombardment (FAB)-Mass spectrum to have inhibition activity on inflammatory factors secreted by Raw 264.7 cells in response to lipopolysaccharide stimulation. Myricetin inhibited nitric oxide (NO) expression in a concentration dependent manner, approximately 40% inhibition was observed at a concentration of 50 μM. The inhibition effect of myricetin on inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX)-2 protein expression was 20% and 80%, respectively, at a concentration of 25 μM. Myricetin also inhibited expression of the inflammatory cytokines, tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6 and prostaglandin E2 (PGE2) in a concentration dependent manner; a concentration of 50 μM, 70%, 80%, 80% and 95% inhibition was observed, respectively. Therefore myricetin isolated from Rhododendron mucronulatum flowers is expected to have an anti-inflammatory effect in Raw 264.7 cell induced by lipopolysaccharides. The results can be expected myricetin from Rhododendron mucronulatum flower to use as functional resource for anti-inflammatory activity.