• 한국환경성돌연변이발암원학회지
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• 제23권1호
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• pp.11-15
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• 2003

Gap junctional intercellular communication (GJIC) plays a key role during development, process of tissue differentiation, and in maintenance of adult tissue homeostasis. Neural stem cells leading to formation of cell clusters termed 'neurospheres', can differentiate into neurons, oligodendrocytes, and astrocytes. We investigated the expression levels and distribution of connexin43 (Cx43) and connexin32 (Cx32), abundant gap junctional protein in neural cells and in neurospheres isolated from rat fetus embryonic day (ED) 17. During differentiation of neurospheres, expression of Cx43 and 32 were increased time-dependently within 72 h, and then decreased at 7 day in western blot analysis. TPA-induced inhibition of GJIC was confirmed by decreased fluorescence by SL/DT assay, and induced hyperphosphorylation of Cx43 while no changes in Cx32 levels in western blot assay. Our results indicate that GJIC may be a crucial role in the differentiation of neuronal stem cell. And this GJIC can be inhibited by TPA through the hyperphosphorylation of Cx43.

• 한국발생생물학회지:발생과생식
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• 제20권4호
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• pp.349-357
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• 2016

The present research was chiefly designed to determine the effect of the treatment of estrogenic agonist, estradiol benzoate (EB), or antiandrogenic compound, flutamide (Flu), at the weaning age on the expression of connexin (Cx) isoforms in the caudal epididymis of adult male rat. Animals were subcutaneously administrated with a single shot of either EB at a low-dose ($0.015{\mu}g$ of EB/kg body weight (BW)) or a high-dose ($1.5{\mu}g$ of EB/kg BW) or Flu at a low-dose ($500{\mu}g$ of EB/kg BW) or a high-dose (5 mg of EB/kg BW). Expressional changes of Cx isoforms in the adult caudal epididymis were examined by quantitative real-time PCR analysis. The treatment of a low-dose EB caused significant increases of Cx30.3, Cx31, Cx32, and Cx43 transcript levels but reduction of Cx31.1, Cx37, and Cx45 expression. Exposure to a high-dose EB resulted in very close responses observed in a low-dose EB treatment, except no significant expressional change of Cx37 and a significant induction of Cx40. Expression of all Cx isoforms, except Cx45, was significantly increased by a low-dose Flu treatment. Expressional increases of all Cx isoforms were detected by a high-dose Flu treatment. The current study demonstrates that a single exposure to estrogenic or antiandrogenic compound during the early postnatal developmental period is sufficient to disrupt normal expression of Cx isoforms in the adult caudal epididymis.

• Journal of Animal Science and Technology
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• 제55권6호
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• pp.521-530
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• 2013

Direct cell-cell communication via the transfer of small molecules between neighboring cells in tissue is accomplished by gap junctions composed of various connexins (Cxs). Proper postnatal development of the epididymis is important for acquisition of male reproduction. The epididymal epithelium is composed of several cell types, and some of these cells are connected by gap junctions. The present study was conducted to determine the presence of Cx transcripts in the corpus and cauda epididymis. In addition, transcriptional changes of Cxs expressed during different postnatal stages were examined by real-time PCR analysis. In both epididymal regions, the same nine Cx transcripts of thirteen Cxs tested were detected. In the corpus epididymis, the highest levels of Cxs31.1 and 37 transcripts were observed at 45 days of age, and amounts of Cxs26, 30.3, and 32 transcripts increased with age and subsequently decreased in the elderly. Expression of Cx31 was greatly increased in the adult and elder stages, while Cxs40, 43, and 45 were abundant in the early postnatal stages. In the cauda epididymis, expression of Cxs26, 30.3, 31.1, 37, and 40 reached the highest levels at 5 months of age. The levels of Cxs31 and 32 mRNAs fluctuated throughout the postnatal period. The amounts of Cxs43 and 45 transcripts were more abundant during the late neonatal and prepubertal ages than later ages. These findings suggest that regional specification of the epididymis is partly regulated by differential expression of Cx genes during the postnatal developmental period.

• Journal of Periodontal and Implant Science
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• 제32권1호
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• pp.129-142
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• 2002

Epithelial-mesenchymal interaction plays a important role in cell growth and differentiation. This interaction is already well known to have an importance during the organ development as well as cell growth and differentiation. However, in vitro experimental model is not well developed to reproduce in vivo cellular microenvironment which provide a epithelial-mesenchymal interaction. Because conventional monolayer culture lacks epithelial-mensenchymal interaction, cultivated cells have an morphologic, biochemical, and functional characteristics differ from in vivo tissue. Moreover, it's condition is not able to induce cellular differention due to submerged culture condition. Therefore, the aims of this study were to develop and evaualte the in vitro experimental model that maintains epithelial-mesenchymal interaction by organotypic raft culture, and to characterize biologic properties of three-dimensionally reconstituted oral keratinocytes by histological and immunohistochemical analysis. The results were as follow; 1. Gingival keratinocytes reconstituted by three-dimensional organotypic culture revealed similar morphologic characteristics to biopsied patient specimen showing stratification, hyperkeratinosis, matutation of epithelial architecture. 2. Connective tissue structure was matured, and there is no difference during stratification period of epithelial 3-dimensional culture. 3. The longer of air-exposure culture on three-dimensionally reconstituted cells, the more epithelial maturation, increased epithelial thickness and surface keratinization 4. In reconstitued mucosa, the whole epidermis was positively stained by anti-involucrin antibody, and there is no difference according to air-exposured culture period. 5. The Hsp was expressed in the epithelial layer of three-dimensionally cultured cells, especially basal layer of epidermis. The change of Hsp expression was not significant by culture stratification. 6. Connexin 43, marker of cell-cell communication was revealed mild immunodeposition in reconstitued epithelium, and there is no significant expression change during stratification. These results suggest that three-dimensional oragnotypic co-culture of normal gingival keratinocytes with dermal equivalent consisting type I collagen and gingival fibroblasts results in similar morphologic and immunohistochemical characteristics to in vivo patient specimens. And this culture system seems to provide adequate micro-environment for in vitro tissue reconstitution. Therefore, further study will be focused to study of in vitro gingivitis model, development of novel perioodntal disease therapeutics and epithelial-mensenchymal interaction.

• 생명과학회지
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• 제16권1호
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• pp.37-43
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• 2006

간극결합은 이웃하는 두 세포 사이에 형성된 이온채널이며 또한 단일세포막에서도 작용한다. 간극결합채널을 형성하는 아미노 말단의 10번째 아미노산 잔기 부위까지가 개폐극성(gating polarity)과 전류-전압관계에 영향을 미친다. 정상적인 Cx32 채널은 음성의 개폐극성과 내향적인 정류현상을 보이는 반면, 음성전하를 띠는 aspartate로 치환된 T8D 채널은 반대의 개폐극성과 직선의 정류현상을 보인다. 이러한 개폐극성과 정류현상의 변화가 전하 자체에 의한 것인지 아니면 아미노 말단의 구조적인 변화에 의한 것인지는 아직 불명확하다. 이러한 문제점을 규명하기 위하여 아미노 말단의 8번째 아미노산 잔기를 cysteine기로 치환시킨 T8C 채널을 만들어 substituted-cysteine accessibility method (SCAM) 방법으로 이 채널의 생물리학적 특성을 조사하고자 하였다. T8C 채널은 정상적인 Cx32 채널처럼 음성의 개폐극성과 내향적인 정류현상을 보였으며, cysteine기로 치환이 정상적인 Cx32 채널의 원래 구조를 변화시키지 않았다는 것을 의미한다. 본 연구에서는 이런 전하효과를 규명하기 위하여 음성 전하를 갖는 MTSES-와 양성전하를 갖는 MTSET+를 사용하였다. MTSES-를 처리하면 T8C 채널은 T8D 채널의 특성처럼 양성의 개폐극성과 직선의 정류현상을 보였다. 그러나 양성전하를 갖는 MTSET+를 처리한 경우에는 T8C 채널은 본래의 특성을 그대로 유지하였다. 작은 분자의 MTS에 의해서 부여된 전하가 아미노 말단의 구조적인 변화를 초래하지는 않을 것으로 생각된다. 따라서 반대의 전하를 띠는 MTSES-와 MTSET+가 서로 상반대는 영향을 미치는 것으로 보아 본 연구에서 관찰된 개폐극성과 전류-전압의 변화는 아미노말단의 구조적인 변화라기보다는 MTS에 의해서 부여된 전하 자체에 기인한다고 할 수 있다. 또한 MTS가 아미노말단의 8번째 부위에 접근하여 반응을 일으킬 수 있다는 결과는 간극결합채널의 아미노말단이 채널의 통로(pore)를 형성한다는 가설을 뒷받침한다.