• Journal of Photoscience
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• 제12권1호
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• pp.1-9
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• 2005

The ubiquitin E3 ligase COP1 (Constitutive Photomorphogenesis 1) is a protein repressor of photomorphogenesis in Arabidopsisplants, and it found in various organisms, including animals. The COP1 protein regulates the stability of many of the light-signaling components that are involved in photomorphogenesis and in the developmental processes. To study the effect of COP1 on flowering in a short day plant, we have cloned a full-length of PnCOP1 (Pharbitis nil COP1) cDNA from Pharbitis nil Choisy cv. Violet, and we examined its transcript levels under various conditions. A full-length PnCOP1 cDNA consists of 2,280 bp nucleotidesthat contain 47 bp of 5'-UTR, 232 bp of 3'-UTR including the poly (A) tail, and 1,998 bp of the coding sequence. The deduced amino acid sequence contains 666 amino acids, giving it a theoretical molecular weight of 75 kD and a isolectric point of 6.2. The PnCOP1 contains three distinct domains, an N-terminal $Zn^2+$-binding RING-finger domain, a coiled-coil structure, and WD40 repeats at the C-terminal, implying that the protein plays a role in protein-protein interactions. The PnCOP1 transcript was detected in the cotyledon, hypocotyls and leaves, but not in root. The levels of the PnCOP1 transcript were reduced in leaves that were a farther distance away from the cotyledons. The expression level of the PnCOP1 gene was inhibited by light, while the expression was increased in the dark. During the floral inductive 16 hour-dark period for Pharbitis nil, the expression was increased and it reached its maximum at the 12th hour of the dark period. The levels of PnCOP1 mRNA were dramatically reduced upon light illumination. These results suggest that PnCOP1 may play an important function in the floral induction of Pharbitis nil.

• Molecules and Cells
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• 제45권10호
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• pp.749-760
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• 2022

Osteoclast generation from monocyte/macrophage lineage precursor cells needs to be tightly regulated to maintain bone homeostasis and is frequently over-activated in inflammatory conditions. PARK2, a protein associated with Parkinson's disease, plays an important role in mitophagy via its ubiquitin ligase function. In this study, we investigated whether PARK2 is involved in osteoclastogenesis. PARK2 expression was found to be increased during the receptor activator of nuclear factor-κB ligand (RANKL)-induced osteoclast differentiation. PARK2 gene silencing with siRNA significantly reduced osteoclastogenesis induced by RANKL, LPS (lipopolysaccharide), TNFα (tumor necrosis factor α), and IL-1β (interleukin-1β). On the other hand, overexpression of PARK2 promoted osteoclastogenesis. This regulation of osteoclastogenesis by PARK2 was mediated by IKK (inhibitory κB kinase) and NF-κB activation while MAPK (mitogen-activated protein kinases) activation was not involved. Additionally, administration of PARK2 siRNA significantly reduced osteoclastogenesis and bone loss in an in vivo model of inflammatory bone erosion. Taken together, this study establishes a novel role for PARK2 as a positive regulator in osteoclast differentiation and inflammatory bone destruction.

• 대한화장품학회:학술대회논문집
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• 대한화장품학회 2003년도 IFSCC Conference Proceeding Book I
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• pp.338-351
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• 2003

UV radiation is the most dangerous stress factor among permanent environmental impacts on human skin. Consequences of UV exposure are aberrant tissue architecture, alterations in skin cells including functional changes. Nowadays new kinds of outdoor leisure-time activities and changing environmental conditions make the question of sun protection more important than ever. It is necessary to recognize that self-confident consumers do not consider to change their way of life, they demand modern solutions on the basis of new scientific developments. In the past one fundamental principle of cosmetics was the use of physical and organic filter systems against damaging UV-rays. Today new research results demonstrate that natural protecting cell mechanisms can be activated. Suitable biological actives strongly support the protection function not from the surface but from the inside of the cell. A soy seed preparation (SSP) was proven to stimulate natural skin protective functions. The major functions are an increased energy level and the prevention of DNA damage. These functions can I be defined as biological UV protection. The tumor suppressor protein p53 plays a key role in the regulation of DNA repair. p53 must be transferred into the phosphorylated form to work as transcription factor for genes which are regulating the cell cycle or organizing DNA repair. A pretreatment with SSP increases the phosphorylation rate of p53 of chronically UV-irradiated human keratinocytes significantly. According to the same test procedure SSP induces a dramatic increase in the expression of the tumor suppressor protein p14$^{ARF}$ that is supporting the p53 activity by blocking the antagonist of p53, the oncoprotein Mdm2. Mdm2, a ubiquitin E3-ligase, downregulates p53 and at the same time it prevents phosphorylation of p53. The positive influence of the tumor suppressor proteins explains the stimulation of DNA repair and prevention of sunburn cell formation by SSP, which was proven in cell culture experiments. In vivo the increased skin tolerance against UV irradiation by SSP could be confirmed too. We have assumed, that an increased repair potential provides full cell functionality.y.

• Journal of Ginseng Research
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• 제48권1호
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• pp.40-51
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• 2024

Background: Ginsenoside 20(S)-Rg3 shows promising tumor-suppressive effects in ovarian cancer via inhibiting NF-kB signaling. This study aimed to explore the downstream tumor suppressive mechanisms of ginsenoside Rg3 via this signaling pathway. Materials and methods: A systematical screening was applied to examine the expression profile of 41 kinesin family member genes in ovarian cancer. The regulatory effect of ginsenoside Rg3 on KIF20A expression was studied. In addition, we explored interacting proteins of KIF20A and their molecular regulations in ovarian cancer. RNA-seq data from The Cancer Genome Atlas (TCGA) was used for bioinformatic analysis. Epithelial ovarian cancer cell lines SKOV3 and A2780 were used as in vitro and in vivo cell models. Commercial human ovarian cancer tissue arrays were used for immunohistochemistry staining. Results: KIF20A is a biomarker of poor prognosis among the kinesin genes. It promotes ovarian cancer cell growth in vitro and in vivo. Ginsenoside Rg3 can suppress the transcription of KIF20A. GST pull-down and co-immunoprecipitation (IP) assays confirmed that KIF20A physically interacts with BTRC (β-TrCP1), a substrate recognition subunit for SCF^β-TrCP E3 ubiquitin ligase. In vitro ubiquitination and cycloheximide (CHX) chase assays showed that via interacting with BTRC, KIF20A reduces BTRC-mediated CDC25A poly-ubiquitination and enhances its stability. Ginsenoside Rg3 treatment partly abrogates KIF20A overexpression-induced CDC25A upregulation. Conclusion: This study revealed a novel anti-tumor mechanism of ginsenoside Rg3. It can inhibit KIF20A transcription and promote CDC25A proteasomal degradation in epithelial ovarian cancer.

• 생명과학회지
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• 제25권3호
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• pp.293-298
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• 2015

근위축은 근육 단백질 합성의 저하와 근육 단백질의 분해 증가에 따른 근섬유의 감소에 의한 근육량이 감소되는 현상이다. 오미자(Schisandrae Fructus, fruits of Schisandra chinensis (Turcz.) Baillon)는 오랫동안 전통의학에서 강장제로서 널리 사용되어 왔다. 비록 다양한 질병 연관 오미자의 생리활성 효능이 폭넓게 연구되어져 왔으나 근육 질환 관련 연구는 매우 제한적으로 이루어져 왔다. 본 연구에서는 오미자 에탄올 추출물(SF)이 AMPK 활성인자 AICAR 처리에 의한 C2C12 근관세포의 근위축 모델계를 이용하여 근위축 억제 효능을 가지는지의 여부와 관련 기전의 해석을 시도하였다. AICAR 처리는 근단백질 분해 연관 ubiquitin ligase muscle RING finger-1 (MuRF-1)의 발현을 전사 수준에서 증가시켰고, MuRF-1 조절 전사인자의 하나인 forkhead box O3a (FoxO3a) 단백질의 인산화를 증가시켰으며, 이러한 변화는 근위축과 연관된 C2C12 근관세포의 형태적 변형과 동반된 현상이었다. 그러나 SF의 전처리에 의하여, AICAR에 의하여 유도된 근위축성 형태변화를 억제하였으며, MuRF-1의 발현과 FoxO3a의 활성화를 억제시켰다. 본 연구의 결과는 SF가 AICAR 처리에 의한 C2C12 근관세포의 근위축을 AMPK 및 FoxO3a 신호전달계 조절을 통하여 억제하였음을 보여주는 것으로 오미자는 근기능 향상을 위한 식의 약 소재로서의 개발 가능성이 매우 높음을 시사하여 준다.

• 생명과학회지
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• 제30권1호
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• pp.106-112
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• 2020

아미노아실-트랜스퍼 리보핵산 합성효소-상호작용 다기능 단백질 2(AIMP2)는 여러 tRNA 합성효소들과의 결합체를 이루게 하는 기능을 하며, DNA 손상에 대한 반응으로 세포사멸 활성을 나타낼 수 있다. DNA에 손상이 발생하면 AIMP2는 MDM2 공격으로부터 p53을 보호하기 위해 MDM2에 결합한다. TGF-β 신호에서 AIMP2는 세포 핵으로 들어가 FUSE 결합 단백질(FBP)과 결합하여 c-myc을 억제한다. TNF 수용체 관련 인자 2(TRAF2)는 c-Jun N-말단 키나아제(JNK), NF-κB 및 p38 미토겐 활성화 단백질 키나아제(MAPKs)의 신호에서 실행되는 두 수용체, TNF 수용체 1과 2 사이의 중요한 중재자이다. TARF2는 TNF-α 신호에서 JNK와 NF-κB의 활성화에 필요하며, 세포사멸 신호를 막는 중재자 역할을 수행한다. 또한 TNF-α 신호에서 AIMP2는 세포사멸을 향상시킨다. 이 신호에서, AIMP2는 TRAF2를 분해하는 것으로 잘 알려진 E3 유비키틴 효소인 c-IAP1과의 결합을 향상시킨다. AIMP2, TRAF2 및 c-IAP1을 포함한 복합체의 형성은 proteasome을 매개로 하여 TRAF2의 분해를 초래한다. 이러한 연구 결과는 AIMP2가 TNF-α 신호에서 직접적인 상호작용을 통해 TRAF2를 하향 조절시켜 세포사멸을 유도할 수 있음을 시사한다.

• Reproductive and Developmental Biology
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• 제34권3호
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• pp.143-151
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• 2010

Pluripotency of human embryonic stem cell (hESC) is one of the most valuable ability of hESCs for applying cell therapy field, but also showing side effect, for example teratoma formation. When transplant multipotent stem cell, such as mesnchymal stem cell (MSC) which retains similar differentiation ability, they do not form teratoma in vivo, but there exist limitation of cellular source supply. Accordingly, differentiation of hESC into MSC will be promising cellular source with strong points of both hESC and MSC line. In this study, we described the derivation of MSC like cell population from feeder free cultured hESC (hESC-MSC) using direct differentiation system. Cells population, hESC-MSC and bone marrow derived MSC (BM-MSC) retained similar characteristics in vitro, such as morphology, MSC specific marker expression and differentiation capacity. At the point of differentiation of both cell populations, differentiation rate was slower in hESC-MSC than BM-MSC. As these reason, to verify differentially expressed molecular condition of both cell population which bring out different differentiation rate, we compare the molecular condition of hESC-MSC and BM-MSC using 2-D proteomic analysis tool. In the proteomic analysis, we identified 49 differentially expressed proteins in hESC-MSC and BM-MSC, and they involved in different biological process such as positive regulation of molecular function, biological process, cellular metabolic process, nitrogen compound metabolic process, macromolecule metabolic process, metabolic process, molecular function, and positive regulation of molecular function and regulation of ubiquitin protein ligase activity during mitotic cell cycle, cellular response to stress, and RNA localization. As the related function of differentially expressed proteins, we sought to these proteins were key regulators which contribute to their differentiation rate, developmental process and cell proliferation. Our results suggest that the expressions of these proteins between the hESC-MSC and BM-MSC, could give to us further evidence for hESC differentiation into the mesenchymal stem cell is associated with a differentiation factor. As the initial step to understand fundamental difference of hESC-MSC and BM-MSC, we sought to investigate different protein expression profile. And the grafting of hESC differentiation into MSC and their comparative proteomic analysis will be positively contribute to cell therapy without cellular source limitation, also with exact background of their molecular condition.

• Molecules and Cells
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• 제37권11호
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• pp.833-840
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• 2014

Cullin4-RING ubiquitin ligase (CRL4) is a family of multi-subunit E3 ligases. To investigate the possible involvement of CRL4 in heat stress response, we screened T-DNA insertion mutants of putative CRL4 substrate receptors that exhibited altered patterns in response to heat stress. One of the mutants exhibited heat stress tolerance and was named heat stress tolerant DWD1 (htd1). Introduction of HTD1 gene into htd1-1 led to recovery of heat sensitivity to the wild type level, confirming that the decrease of HTD1 transcripts resulted in heat tolerance. Therefore, HTD1 plays a negative role in thermotolerance in Arabidopsis. Additionally, HTD1 directly interacted with DDB1a in yeast two-hybrid assays and associated with DDB1b in vivo, supporting that it could be a part of a CRL4 complex. Various heat-inducible genes such as HSP14.7, HSP21, At2g03020 and WRKY28 were hyper-induced in htd1-1, indicating that HTD1 could function as a negative regulator for the expression of such genes and that these genes might contribute to thermotolerance of htd1-1, at least in part. HTD1 was associated with HSP90-1, a crucial regulator of thermotolerance, in vivo, even though the decrease of HTD1 did not affect the accumulation pattern of HSP90-1 in Arabidopsis. These findings indicate that a negative role of HTD1 in thermotolerance might be achieved through its association with HSP90-1, possibly by disturbing the action of HSP90-1, not by the degradation of HSP90-1. This study will serve as an important step toward understanding of the functional connection between CRL4-mediated processes and plant heat stress signaling.

• Journal of Microbiology and Biotechnology
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• 제33권9호
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• pp.1206-1212
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• 2023

The Wnt/β-catenin pathway plays essential roles in regulating various cellular behaviors, including proliferation, survival, and differentiation [1-3]. The intracellular β-catenin level, which is regulated by a proteasomal degradation pathway, is critical to Wnt/β-catenin pathway control [4]. Normally, casein kinase 1 (CK1) and glycogen synthase kinase-3β (GSK-3β), which form a complex with the scaffolding protein Axin and the tumor suppressor protein adenomatous polyposis coli (APC), phosphorylate β-catenin at Ser45, Thr41, Ser37, and Ser33 [5, 6]. Phosphorylated β-catenin is ubiquitinated by the β-transducin repeat-containing protein (β-TrCP), an F-box E3 ubiquitin ligase complex, and ubiquitinated β-catenin is degraded via a proteasome pathway [7, 8]. Colorectal cancer is a significant cause of cancer-related deaths worldwide. Abnormal up-regulation of the Wnt/β-catenin pathway is a major pathological event in intestinal epithelial cells during human colorectal cancer oncogenesis [9]. Genetic mutations in the APC gene are observed in familial adenomatous polyposis coli (FAP) and sporadic colorectal cancers [10]. In addition, mutations in the N-terminal phosphorylation motif of the β-catenin gene were found in patients with colorectal cancer [11]. These mutations cause β-catenin to accumulate in the nucleus, where it forms complexes with transcription factors of the T-cell factor/lymphocyte enhancer factor (TCF/LEF) family to stimulate the expression of β-catenin responsive genes, such as c-Myc and cyclin D1, which leads to colorectal tumorigenesis [12-14]. Therefore, downregulating β-catenin response transcription (CRT) is a potential strategy for preventing and treating colorectal cancer. Plant cytokinins are N⁶-substituted purine derivatives; they promote cell division in plants and regulate developmental pathways. Natural cytokinins are classified as isoprenoid (isopentenyladenine, zeatin, and dihydrozeatin), aromatic (benzyladenine, topolin, and methoxytopolin), or furfural (kinetin and kinetin riboside), depending on their structure [15, 16]. Kinetin riboside was identified in coconut water and is a naturally produced cytokinin that induces apoptosis and exhibits antiproliferative activity in several human cancer cell lines [17]. However, little attention has been paid to kinetin riboside's mode of action. In this study, we show that kinetin riboside exerts its cytotoxic activity against colon cancer cells by suppressing the Wnt/β-catenin pathway and promoting intracellular β-catenin degradation.

• 생약학회지
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• 제35권4호통권139호
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• pp.368-374
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• 2004

Cervical cancer is one of the leading causes of female death. Viral oncoproteins E6 and E7 are selectively retained and expressed in carcinoma cells infected with HPV (Human papillomavirus) type 16. The HPV is cooperated in immotalization and transformation of primary keratinocyte. E6 and E7 oncoproteins interfere the functions of tumor suppressor proteins p53 and retinoblasoma protein (pRb), respectively. Among a lots of natural products, Artemisia scoparia Waldstein et Kitamura has inhibitory effects on the binding between E6 oncoprotein and tumor suppressor p53, or the binding between E6 and E6 associated protein (E6AP), an E3 ubiquitin-protein ligase. HPV oncoprotein inhibitors from Artemisia scoparia W. were isolated by solvent partition and column chromatography (Silica gel, RP-18) and the inhibitory compounds were finally purified by HPLC using an ELISA screening system based on the binding between E6 and E6AP. The aim of this study is to identify the structure of inhibitory compounds and to investigate whether these compounds have inhibitory effects on the functions of E6 oncoprotein. We investigated whether 3,5-di-O-caffeoylquinic acid (DCQA) extracted from Artemisia scoparia W. Could inhibit the function of E6 oncoprutein. DCQA inhibited the in vitro binding of E6 and E6AP which are essential for the binding and degradation of the tumor suppressor p53 and also inhibited the proliferation of human cervical cancer cell lines (SiHa and CaSKi) in a dose response manner. These results suggest that DCQA inhibited the function of E6 oncoprotein, suggesting that it can be used as a potential drug for the treatment of cervical cancers infected with HPV.