• Applied Microscopy
• /
• 제25권2호
• /
• pp.53-64
• /
• 1995

세포막의 결합장치들은 형태학적으로나 기능적으로 분화된 특이한 구조이며 각기 인접한 세포막 사이의 특징적인 부위에 위치한다. 그러나 이들 결합장치가 간세포의 기능상태에 연관하여 미세구조적으로 어떠한 변화를 보이는지에 관해서는 아직 잘 알려져 있지 않다. 본 연구는 간세포의 기능적 변동에 따르는 간세포막 사이 결합장치의 형태학적 변화를 알아보기 위하여 정상군과 8일간 기아 시킨 기아군으로 구분한 휜쥐 ($Wister,\;{\uparrow},\;250{\sim}280g$)에서 절취된 간조직을 박절편과 급속동결할 단복제법에 의거 표본을 제작하여 이들 결합장치의 미세구조상을 비교 고찰하였다. 그 결과 담세관주위의 폐쇄띠는 기아상태에서 현저히 감축되거나 소실되어 있었는데 이러한 소견은 박절편과 급속동결할단복제에서 다 같이 관찰되었으며 기아상태하에서 결합반과 교통반의 현저한 증가를 볼 수 있었다. 또한 정상상태하에서 이들 결합장치가 비교적 일정한 구조를 유지하고 있을 것이라는 일반적인 견해와는 달리 본 연구에서는 박절편이나 급속동결할단복제에서 다 같이 폐쇄띠가 부위에 따라 현저한 구조적 차이를 보였다. 본 연구에서 얻어진 이러한 결과로 미루어 폐쇄띠의 감축이나 소실은 기아로 인한 간세포의 기능저하가 담즙물질의 생성을 저해하게 됨으로서 담세관의 내압이 저하된 데 기인된 현상으로 생각된다. 또한 결합반의 증가는 기아로 인하여 감축된 간세포를 지지하므로서 간조직의 유지를 도우려는데 있었을 것이며 교통반의 증가는 기아로 인한 간세포의 기능적 저하가 간세포상호간의 물질교환을 필요로 하였기 때문이었을 것으로 추정된다. 특히 정상상태하에서도 부위에 따라 폐쇄띠의 미세구조적 변화가 있었던 것은 이 결합장치가 간세포의 기능이나 담세관의 상태에 민감하게 반응하기 때문일 것으로 생각된다.

• Asian-Australasian Journal of Animal Sciences
• /
• 제27권4호
• /
• pp.580-586
• /
• 2014

Intestinal epithelial cells (IECs) forming the barrier for the first-line of protection are interconnected by tight junction (TJ) proteins. TJ alteration results in impaired barrier function, which causes potentially excessive inflammation leading to intestinal disorders. It has been suggested that toll-like receptor (TLR) 2 ligands and some bacteria enhance epithelial barrier function in humans and mice. However, no such study has yet to be claimed in swine. The aim of the present study was to examine whether Bacillus subtilis could improve barrier integrity and protection against deoxynivalenol (DON)-induced barrier disruption in porcine intestinal epithelial cell line (IPEC-J2). We found that B. subtilis decreased permeability of TJ and improved the expression of zonula occludens (ZO)-1 and occludin during the process of forming TJ. In addition, ZO-1 expression of IPEC-J2 cells treated with B. subtilis was up-regulated against DON-induced damage. In conclusion, B. subtilis may have potential to enhance epithelial barrier function and to prevent the cells from DON-induced barrier dysfunction.

• Journal of Animal Science and Technology
• /
• 제64권3호
• /
• pp.500-514
• /
• 2022

The blood-epididymis barrier (BEB) forms a unique microenvironment that is crucial for the maturation, protection, transport, and storage of spermatozoa in the epididymis. To characterize the function of tight junctions (TJs), which are constitutive components of the BEB, we determined the expression and localization of TJ proteins such as zonula occludens (ZO)-1, 2, and 3, occludin, and claudin3 (Cldn3) during postnatal development in the goat epididymis. To assess the expression patterns of TJ proteins in immature (3 months of age) and mature (14 months of age) goat epididymides, two different experimental methods were used including immunofluorescence labeling and western blotting. We show that, ZO-1, 2, and 3, and occludin, were strictly expressed and localized to the TJs of the goat epididymis, whereas Cldn3 was present in basolateral membranes as well as TJs. All TJ proteins examined were more highly expressed in the immature epididymis compared to levels in mature tissue. In conclusion, our study indicates that at least five TJ proteins, namely ZO-1, ZO-2, ZO-3, occludin, and Cldn3, are present in TJs, and the expression strength and pattern of TJ proteins tend to be age dependent in the goat epididymis. Together, these data suggest that the distinct expression patterns of TJ proteins are essential for regulating components of the luminal contents in the epididymal epithelium and for forming adequate luminal conditions that are necessary for the maturation, protection, transport, and storage of spermatozoa in the goat epididymis.

• 한국생물물리학회:학술대회논문집
• /
• 한국생물물리학회 2001년도 학술 발표회 진행표 및 논문초록
• /
• pp.21-21
• /
• 2001

PDZ domains are molecular-recognition elements that mediate protein-protein interactions. The PDZ domain was discovered originally as a common motif present in three structurally related proteins： PSD-95 (postsynaptic density protein), Dlg (discs-large protein) and ZQ-1 (zonula occludens-1). The PDZ domain is globular domain, containing about 80-100 amino acids, and a conserved motif with two alpha helices and six beta strands. Most of them bind selectively to the C-termini of the interacting proteins at the complexes of signaling molecules and membrane associated receptors.(omitted)

• Journal of Microbiology and Biotechnology
• /
• 제30권10호
• /
• pp.1480-1487
• /
• 2020

Our previous report determined that miR-144 is a key regulator of intestinal epithelial permeability in irritable bowel syndrome with diarrhea (IBS-D) rats. Recent evidence has shown that lactobacilli play an important role in the relief of IBS-D symptoms. However, few studies have addressed the mechanisms by which microRNAs and lactobacilli exert their beneficial effects on intestinal epithelial permeability. Hence, to elucidate whether miRNAs and lactobacilli play roles in intestinal epithelial barrier regulation, we compared miRNA expression levels in intestinal epithelial cells (IECs) under Lactobacillus casei (L. casei LC01) treatment. IECs and L. casei LC01 were co-cultured and then subjected to microRNA microarray assay. qRT-PCR, western blot and ELISA were used to detect the expression of occludin (OCLN) and zonula occludens 1 (ZO1/TJP1). The interaction between miRNAs and L. casei LC01 acting in IECs was investigated through transfection of RNA oligoribonucleotides and pcDNA 3.1 plasmid. The results are as follows: 1) L. casei LC01 decreased the expression of miR-144 and FD4 and promoted OCLN and ZO1 expression in IECs; 2) L. casei LC01 enhanced the barrier function of IECs via downregulation of miR-144 and upregulation of OCLN and ZO1; 3) Under L. casei LC01 treatment, OCLN and ZO1 overexpression could partially eliminate the promoting effect of miR-144 on intestinal permeability in IECs. Our results demonstrate that L. casei LC01 regulates intestinal permeability of IECs through miR-144 targeting of OCLN and ZO1. L. casei LC01 can be a possible therapeutic target for managing dysfunction of the intestinal epithelial barrier.

• 생명과학회지
• /
• 제25권1호
• /
• pp.101-112
• /
• 2015

자가밀착연접 단백질들은 세포, 특히 수초화된 신경교세포막의 층상구조 사이에 존재하는 밀착연접에 존재한다. 그들 중 일부는 다른 단백질의 C-말단의 PDZ 결합 모티프에 붙는 postsynaptic density-95/Disks large/Zonula occludens-1 (PDZ) 도메인을 가진다. PDZ domain은 박테리아, 식물, 세균, 후생동물, Drosophila에 존재하여 거대한 단백복합체를 형성할 수 있게 해준다. 이러한 단백복합체들은 세포 내 신호전달, 단백질 표적화, 그리고 세포막 극화 작용을 한다. ZO-1, ZO-2, AF-6, PATJ, MUPP1, PAR-3는 자가밀착연접에 존재한다고 확인되었다. PAR-3는 atypical protein kinase C와 PAR-6와 반응하여 세포의 극성 형성에 중요한 역할을 하는 3차원 단백질복합체를 형성하는데 이는 Caenorhabditis elegans와 Drosophila 종에서 척추동물에까지 보존되었다. MAGI2는 흥분성 시냅스에서 ${\alpha}$-amino-3-hydroxyl-5-methyl-4-isoxazole propionate (AMPA) 수용체와 반응한다. PATJ는 claudin-1과 함께 마디곁 루프에서 발견되는 반면, MUPP1은 claudin-5와 함께 축삭사이막과 Schmidt-Lanterman 절흔에서 찾을 수 있다. ZO-1, ZO-2 그리고 PAR-3의 경우에는 세 장소 모두에서 발견된다. PDZ 도메인을 보유한 단백질들의 서로 다른 분포는 자가밀착연접의 발생에 영향을 준다. 이 총설에서는 수초화된 슈반 세포의 자가밀착연접에 존재하는 PDZ 도메인을 가진 단백질들과 그들의 기능을 알아볼 것이다.

• 대한수의학회지
• /
• 제37권1호
• /
• pp.87-101
• /
• 1997

The development of trachea in fetuses on 60, 90 and 120 days of gestation and neonates of Korean native goats was investigated by microscopy and scanning and transmission electron microscopy. The results were summarized as follows; Light microscopic studies: 1. In the 60-day-old fetuses, the tracheal walls were differentiated and divided into four layers of the mucosa, submucosa, muscle and cartilage, and adventitia. The tracheal epithelium is composed of stratified ciliated columnar epithelium at 60- and 90-day-old fetuses while the epithelium observed at 120-day-old fetuses was pseudostraified ciliated colummar epithelium. 2. In the 90-day-old fetuses, tracheal glands extended into the submucosa and peripheral area of the tracheal cartilage. The blood vessels were observed in the submucosa and adventitia. The elastic and collagenous fibers were observed in the tracheal walls. 3. In the neonates, the tracheal walls consisted of mucosa with well-developed folds, submucosa, tracheal glands, muscle and cartilage, collagenous and elastic fibers, and adventitia, which were more developed than those of 120-day-old fetuses. The tracheal epithelium was developed as that in adults. Scanning electron microscopic studies: 4. In the 60-day-old fetuses, most of tracheal epithelial cells were nonciliated but short microvilli were sporadically observed on the luminal surface. On rare occasions, a few cells have solitary cilium. 5. In the 90-day-old fetuses, the ciliated cells appeared increasingly and cilia elongated longer than those of 60-day-old fetuses. 6. In the 120-day-old fetuses, the nonciliated cells covered with microvilli in dome-shape were barriered by thick carpet of cilia. The nonciliated cells also have many papillary projectons on the apical surface. 7. In the neonates, the nonciliated cells in tracheal epithelium were covered compactly with numerous cilia, and many secretory droplets were found on the cilia. Transmission electron microscopic studies: 8. In the 60-day-old fetuses, nonciliated cells of the tracheal epithelium contain large amounts of glycogen granules in the supernuclear and subnuclear areas meanwhile a few cell organelles were formed. Cilia were well formed along the apical cell membranes of the ciliated cells. Also found in the ciliated cells were basal corpuscles, mitochondria and short chains in granular endoplasmic reticulum(GER). Between the epithelial cells presented were well-defined junctional complex with zonula occludens and desmosomes. The nuclei were variable in size and shape. The more developed nucleoli were observed conspicuosly. 9. In the 90-day-old fetuses, nonciliated cells contained large glycogen granules. Accumulated glycogen granules were observed in the subnuclear and supranuclear portion of the cytoplasm. A few short microvilli were covered with glycocalyx. Ciliated cells contained numerous mitochondria and short chains of GER. 10. In the 120-day-old fetuses, the ciliated cells contained numerous mitochondria, abundant short chains of GER and nucleoli. Nonciliated cells contained some Golgi complex and mitochondria. The cell borders were well-defined and distinct junctional complex with zonula occludens, desmosomes, and interdigitorum. 11. In the neonates, well-developed goblet cells were observed in the tracheal epithelium. Ultrastructures of ciliated and nonciliated cells on the tracheal epithelia were similar in pattern as those in adults.

• Journal of Ginseng Research
• /
• 제37권1호
• /
• pp.94-99
• /
• 2013

Proteinuric conditions demonstrate structural and compositional changes of the foot processes and slit diaphragms between podocytes. p130Cas in podocytes serves as an adapter protein anchoring glomerular basement membrane to actin filaments of podocyte cytoskeleton. To investigate the effect of ginseng total saponin (GTS) on the pathologic changes of podocyte p130Cas induced by diabetic conditions, we cultured mouse podocytes under: 1) normal glucose (5 mM, control); 2) high glucose (HG, 30 mM); 3) advanced glycosylation endproducts (AGE)-added; or 4) HG plus AGE-added conditions and treated with GTS. In confocal imaging, p130Cas colocalized with zonula occludens-1 and synaptopodin connecting to F-actin. However, diabetic conditions relocalized p130Cas molecules at perinuclear cytoplasmic area and reduced the intensity of p130Cas. In Western blotting, diabetic conditions, especially HG plus AGE-added condition, decreased cellular p130Cas protein levels at 24 and 48 h. GTS improved such quantitative and qualitative changes. These findings imply that HG and AGE have an influence on the redistribution and amount of p130Cas of podocytes, which can be reversed by GTS.

• 생명과학회지
• /
• 제24권12호
• /
• pp.1276-1283
• /
• 2014

조직의 구조 안정성을 유지하는 세포 사이 연접복합체는 multi-PDZ domain protein 1 (MUPP1)을 포함하여 50종류 이상의 단백질로 이루어져 있다. MUPP1은 13개의 PDZ 도메인을 가지는 단백질로서 막경유(transmembrane) 단백질과 세포골격단백질이나 신호단백질 사이에서 scaffold로 작용한다고 알려져 있지만, MUPP1이 어떻게 세포막인접 단백질들을 연결하고 구조 안정화에 기여하는지에 대해 아직 명확히 밝혀지지 않았다. 본 연구에서 MUPP1의 PDZ 도메인과 상호 작용하는 단백질을 규명하기 위하여 효모 two-hybrid 방법을 이용, cell adhesion molecule 1 (Cadm1; SynCAM1, Necl-2 또는 TSLC1로도 알려짐)이 MUPP1과 결합하는 것을 확인하였다. Cadm1은 MUPP1의 2번째 PDZ 도메인과 결합하며, Cadm1의 C-말단에 존재하는 II 형 PDZ-결합모티프(-Y-F-I)가 MUPP1과의 결합에 필수적임을 확인하였다. 또한 MUPP1은 다른 Cadm family 단백질들인 Cadm2, Cadm3, 그리고 Cadm4와도 결합하며, 이러한 단백질간 결합은 glutathione S-transferase (GST) pull-down assay와 공동면역침강으로도 추가 확인하였다. 생쥐의 뇌 파쇄액을 MUPP1 항체로 면역침강하였을 때 Cadm1과 Cadm4가 같이 침강하였다. 이러한 결과들은 MUPP1이 세포 사이 연접에서 Cadms와 세포골격 단백질 사이를 연결한다는 것을 시사한다.

• Journal of Veterinary Science
• /
• 제24권3호
• /
• pp.23.1-23.16
• /
• 2023

Background: Irritable bowel syndrome (IBS) is a functional bowel disorder (FBD). Objectives: To assess the therapeutic effects of paeoniflorin (PF) on IBS in rats. Method: Sixty male Sprague-Dawley rats were randomly divided into normal, model, positive drug, low-dose PF, medium-dose PF and high-dose PF groups (n = 10). After gavage for 2 consecutive weeks, the effect of PF on abdominal pain symptoms was assessed based on the abdominal withdrawal reflex (AWR) score, fecal water content and pathological changes in colon tissues. D-lactate, interleukin-1β (IL-1β), transforming growth factor-β (TGF-β) and tumor necrosis factor-α (TNF-α) were detected by enzyme-linked immunosorbent assay, and phosphorylated nuclear factor kappa B (p-NF-κB) p65 was detected by Western blotting. The abundance and diversity changes of intestinal flora were explored using 16S ribosomal RNA sequencing. Result: In PF groups, the mucosal morphology of colon tissues was intact, and the glands were arranged neatly and structured clearly, without obvious inflammatory cell infiltration. Compared with the model group, PF groups had significantly elevated pain threshold, and mRNA and protein levels of zonula occludens-1 (ZO-1) and occludin, decreased AWR score at 20 mmHg pressure, fecal water content, mRNA levels of IL-1β, TGF-β, and TNF-α, protein level of p-NF-κB p65 and level of serum D-lactate, and reduced levels of serum IL-1β, TGF-β, and TNF-α (p < 0.05, p < 0.01). PF groups had higher abundance of Lactobacillus, Akkermansia, Alistipes, and Bacteroides, but lower abundance of Desulfovibrio, Parasutterella, and Enterococcus than those of the model group. Conclusions: PF exerts therapeutic effects on IBS in rats probably by regulating the intestinal flora, and then up-regulating the expressions of ZO-1 and occludin in colon tissue while down-regulating the levels of IL-1β, TGF-β, TNF-α, D-lactate and p-NF-κB p65.