• IMMUNE NETWORK
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• 제6권3호
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• pp.123-127
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• 2006

Background: Caveolin-1 is a principal component of caveolae membranes in vivo. Although expression of caveolae structure and expression of caveolin family, caveolin-1, -2 and -3, was known in chondrocytes, the functional role of caveolae and caveolins in chondrocytes remains unknown. In this study, we investigated the role of caveolin-1 in articular chondrocytes. Methods: Rabbit articular chondrocytes were prepared from cartilage slices of 2-week-old New Zealand white rabbits by enzymatic digestion. Caveolin-1 cDNA was transfected to articular chondrocytes using LipofectaminePLUS. The cyclooxygenase-2 (COX-2) expression levels were determined by immunoblot analysis, immunostaining, immunohistochemistry, and prostaglandin $E_2\;(PGE_2)$ assay was used to measure the COX-2 activity. Results: Ectopic expression of caveolin-1 induced COX-2 expression and activity, as indicated by immunoblot analysis and $PGE_2$ assay. And also, overexpression of caveolin-1 stimulated activation of p38 kinase and ERK-1/-2. Inhibition of p38 kinase and ERK-1/-2 with SB203580 and PD98059, respectively, led to a dose-dependent decrease COX-2 expression and $PGE_2$ production in caveolin-1-transfected cells. Conclusion: Taken together, our data suggest that ectopic expression of caveolin-1 contributes to the expression and activity of COX-2 in articular chondrocytes through MAP kinase pathway.

• BMB Reports
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• 제45권11호
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• pp.612-622
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• 2012

Olfactory receptors (ORs) detect volatile chemicals that lead to the initial perception of smell in the brain. The olfactory receptor (OR) is the first protein that recognizes odorants in the olfactory signal pathway and it is present in over 1,000 genes in mice. It is also the largest member of the G protein-coupled receptors (GPCRs). Most ORs are extensively expressed in the nasal olfactory epithelium where they perform the appropriate physiological functions that fit their location. However, recent whole-genome sequencing shows that ORs have been found outside of the olfactory system, suggesting that ORs may play an important role in the ectopic expression of non-chemosensory tissues. The ectopic expressions of ORs and their physiological functions have attracted more attention recently since MOR23 and testicular hOR17-4 have been found to be involved in skeletal muscle development, regeneration, and human sperm chemotaxis, respectively. When identifying additional expression profiles and functions of ORs in non-olfactory tissues, there are limitations posed by the small number of antibodies available for similar OR genes. This review presents the results of a research series that identifies ectopic expressions and functions of ORs in non-chemosensory tissues to provide insight into future research directions.

• Plant Biotechnology Reports
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• 제4권1호
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• pp.53-59
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• 2010

A specific deleted version of ARABIDOPSIS RESPONSE REGULATOR1 (ARR1) lacking the signal receiver domain (1.152 amino acids)-coding sequence, referred to as $ARR1{\Delta}DDK$, was amplified using Arabidopsis thaliana cDNA prepared from adult leaves and transferred into the genome of Nicotiana tabacum cv. Samsun under the transcriptional control of a ${\beta}$-estradiol-inducible expression system. The ectopic expression of $ARR1{\Delta}DDK$ affected the morphology of transgenic seedlings and their segments in vitro. In the presence of an inducer, ${\beta}$-estradiol, ectopic expression of $ARR1{\Delta}DDK$ induced only the formation of soft, pseudo-bulbous tissue in the root tip region of intact seedlings, which appeared similar to callus generated on a hypocotyl segment in the presence of 2,4-D and 6-benzyladenine (BA), both at $1\;{\mu}M$. Those callus tissues on the root tip region could not generate shoots unless $1\;{\mu}M$ BA was supplied. In segment culture, ectopic expression of $ARR1{\Delta}DDK$ induced calluslike tissue around the cut-end of cotyledon and hypocotyl segments with occasional shoot formation, suggesting that the expression of $ARR1{\Delta}DDK$ could substitute for the effects of cytokinin on these segments. Additionally, treatment with only ${\beta}$-estradiol induced NtWUS, a WUS ortholog in tobacco, which was detected during the process of callus tissue formation in the root tip region and also in cotyledon or hypocotyl segments. These findings suggest that the NtWUS might be associated in the transdifferentiation process caused by the functional regulation of $ARR1{\Delta}DDK$ in transgenic tobacco seedlings.

• Journal of Microbiology and Biotechnology
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• 제17권1호
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• pp.130-137
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• 2007

A disease resistance related gene, MbR7, was identified in the wild apple species, Malus baccata. The MbR7 gene has a single open reading frame (ORF) of 3,288 nucleotides potentially encoding a 1,095-amino acid protein. Its deduced amino acid sequence resembles the N protein of tobacco and the NL27 gene of potato and has several motifs characteristic of a TIR-NBS-LRR R gene subclass. Ectopic expression of MbR7 in Arabidopsis enhanced the resistance against a virulent pathogen, Pseudomonas syringae pv. tomato DC3000. Microarray analysis confirmed the induction of defense-related gene expression in 35S::MbR7 heterologous Arabidopsis plants, indicating that the MbR7 gene likely activates a downstream resistance pathway without interaction with pathogens. Our results suggest that MbR7 can be a potential target gene in developing a new disease-resistant apple variety.

• BMB Reports
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• 제40권6호
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• pp.1095-1099
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• 2007

Endonuclease G (EndoG) is a mitochondrial non-specific nuclease that is highly conserved among the eukaryotes. Although the precise role of EndoG in mitochondria is not yet known, the enzyme is released from the mitochondria and digests nuclear DNA during apoptosis in mammalian cells. Schizosaccharomyces pombe has an EndoG homolog Pnu1p (previously named SpNuc1) that is produced as a precursor protein with a mitochondrial targeting sequence. During the sorting into mitochondria the signal sequence is cleaved to yield the functionally active endonuclease. From the analogy to EndoG, active extramitochondrial Pnu1p may trigger cell killing by degrading nuclear DNA. Here, we tested this possibility by expressing a truncated Pnu1p lacking the signal sequence in the extramitochondrial region of pnu1-deleted cells. The truncated Pnu1p was localized in the cytosol and nuclei of yeast cells. And ectopic expression of active Pnu1p led to cell death with fragmentation of nuclear DNA. This suggests that the Pnu1p is possibly involved in a certain type of yeast cell death via DNA fragmentation. Although expression of human Bak in S. pombe was lethal, Pnu1p nuclease is not necessary for hBak-induced cell death.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제29권6호
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• pp.499-508
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• 2007

Background and Purpose: Some subtypes of malignant salivary gland tumors such as adenoid cystic carcinoma (ACC) frequently result in distant metastasis of vascular origin, which are main causes of treatment failure. The reasons for the affinity for vascular metastatic potential are unclear. Therefore, molecular characteristics that influence the dissemination of metastatic tumor cells are important for the design of more effective treatment of salivary ACC. Tumor angiogenesis has been known to be essential for the distant metastasis of malignant cells. So, we determined expressions of vascular metastasis related factors in orthotopic (parotid) murine models of parotid ACC and compared with those in ectopic (subcutis) tumors of athymic mice. Experimental Design: Using specimens from murine parotid (orthotopic, experimental group) and subcutaneous (ectopic, control group) tumors, which have developed via transplantation of tumor cells, originated from human parotid ACC, we performed immunohistochemical assays with anti-vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF, FGF2), matrix metalloproteinase (MMP)-9, and interleukin (IL)-8 antibodies. We also performed immunohistochemical assays with VEGF receptor (VEGFR)-1, VEGFR-2, VEGFR-3, and phosphorylated VEGFR-2. Results: Transplantation of human ACC tumor cell $(5{\times}10^5)$ into the parotid and subcutis successfully resulted in orthotopic (parotid) and ectopic (subcutaneous) tumors in athymic mice. Immunohistochemical staining demonstrated higher expression of major angiogenic factors (VEGF, bFGF, MMP-9) in the orthotopic tumors than in ectopic tumors (P<0.05). But the expression level of angiogenic receptors were same in orthotopic and ectopic tumors of parotid ACC. Conclusion: VEGF, bFGF, and MMP-9 could be a good candidates for antiangiogenic therapy for the contol of vascular metastatic lesions of salivary ACC.

• BMB Reports
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• 제50권7호
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• pp.379-383
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• 2017

We previously reported that p53 plays a role as a key regulator in the tetraploid G1 checkpoint, which is activated by actin damage-induced cytokinesis blockade and then prevents uncoupled DNA replication and nuclear division without cytokinesis. In this study, we investigated a role of Skp2, which targets CDK2 inhibitor p27/Kip1, in actin damage-induced tetraploid G1 arrest. Expression of Skp2 was reduced, but p27/Kip1 was increased, after actin damage-induced cytokinesis blockade. The role of Skp2 repression in tetraploid G1 arrest was investigated by analyzing the effects of ectopic expression of Skp2. After actin damage, ectopic expression of Skp2 resulted in DNA synthesis and accumulation of multinucleated cells, and ultimately, induction of apoptosis. These results suggest that Skp2 repression is important for sustaining tetraploid G1 arrest after cytokinesis blockade and is required to prevent uncoupled DNA replication and nuclear division without cytokinesis.

• 한국동물학회:학술대회논문집
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• 한국동물학회 2000년도 한국생물과학협회 학술발표대회
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• pp.201.1-201
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• 2000

• 생명과학회지
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• 제22권10호
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• pp.1316-1323
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• 2012

본 연구는 한우유래 myoblast에서 지방세포분화 유도 전사인자들을 과발현시켜 지방세포로의 교차분화를 유도하기 위하여 실시하였다. 한우 유래 satellite cell을 배양한 후 adipogenic transcription factor인 $PPAR{\gamma}$, C/$EBP{\alpha}$, SREBP1c, KLF5등을 단독 또는 co-transfection을 실시하여 세포에 과발현을 유도하였다. 이들 세포들은 adipogenic differentiation medium에서 2일간 배양한 후growth medium에서 8일간 추가로 배양하였다. 지방세포로의 교차분화 유무는 Oil-red O염색과 지방세포 마커 유전자들의 발현으로 확인하였다. $PPAR{\gamma}$과 C/$EBP{\alpha}$를 각각 단독으로 과발현을 유도한 경우myoblast에서 지방세포로의 교차분화를 유도하기에는 충분하지 못하였다. 그러나 $PPAR{\gamma}$와 C/$EBP{\alpha}$을 co-transfection을 실시한 경우 지방세포로의 교차분화가 유도되었고, 세포내지방구형성, 지방세포 마커유전자의 발현, 근세포 마커유전자의 발현 감소 등이 확인되었다. KLF5 와 $PPAR{\gamma}$를 동시에 과발현할 경우 지방세포로의 교차분화를 볼 수 있었지만 KLF단독의 경우는 교차분화를 유도하지 못하였다. 할성형SREBP1c (tSREBP1c)의 경우, 단독으로 myoblast에 과발현을 처리한 경우만으로 지방세포로의 교차분화를 유도할 수 있었다. 이들 결과는 한우유래 satellite cell을 이용하여 지방세포분화 전사인자를 단독 혹은 조합하여 이들 세포에 과발현 시킬 경우 지방세포로의 교차분화를 유도할 수 있음을 보여 주었다.

• Clinical and Experimental Reproductive Medicine
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• 제34권3호
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• pp.149-157
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• 2007

목 적: 본 연구는 세포간 부착과 유착에 관여하는 당단백질의 하나인 osteopontin (OPN)의 mRNA와 단백질의 발현 양상을 자궁내막증 환자의 정상위치 자궁내막조직과 이소성 자궁내막조직, 대조군의 자궁내막조직에서 비교, 분석하기 위해 시행되었다. 연구방법: 개복 또는 복강경 수술을 통하여 자궁내막증으로 확진된 환자 32명을 연구 대상으로 하였고 같은 시기에 자궁경부 상피내암 또는 자궁내막증 이외의 양성 부인과 질환으로 수술적 치료를 받은 환자 34명을 대조군으로 하였다. 수술 시 자궁내막종 또는 복강내 자궁내막 이식물로부터 이소성 자궁내막조직을 얻었고, 동시에 정상위치 자궁내막조직을 생검하였다. 자궁내막조직 내의 OPN mRNA의 발현 정도는 실시간 역전사 중합효소연쇄반응을 이용하여 비교하고 단백질 발현에는 western blot 분석을 사용하였다. 각 군 간의 비교에는 ANOVA와 Krusxal-Wallis test를 사용하였으며 p-value 0.05 미만을 유의한 것으로 판정하였다. 결 과: 월경주기의 증식기와 분비기 모두에서 자궁내막중 환자의 정상위치 및 이소성 자궁내막조직에서의 OPN mRNA의 발현은 대조군의 자궁내막조직에 비해 유의하게 높은 것으로 나타났다 자궁내막중 환자에서 정상위치 자궁내막조직의 경우 OPN mRNA의 발현은 증식기에 비해 분비 기에서 의미 있게 증가하였으나 이소성 자궁내막 조직에서는 분비기에서 뚜렷하게 감소하는 양상으로 나타났다. OPN 단백질의 발현도 mRNA의 발현과 마찬가지로 자궁내막중 환자에서 유의하게 높은 것으로 확인되었다. 결 론: 본 연구의 결과는 자궁내막증이 있는 여성의 정상위치 및 이소성 자궁내막 조직에서의 증가된 OPN mRNA 및 단백질의 발현이 자궁내막 조직의 유착 및 침습에 관여할 수 있음을 시사한다.