The role of the cell adhesion molecule uvomorulin in the formation and maintenance of the epithelial junctional complex.
The role of the cell adhesion molecule uvomorulin in the formation and maintenance of the epithelial junctional complex.
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DOI：
10.1083/jcb.107.4.1575
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发表时间：
1988-10
期刊：
影响因子：
--
通讯作者：
Grimaldi A
中科院分区：
文献类型：
--
作者：
Gumbiner B;Stevenson B;Grimaldi A
研究了上皮粘附分子uvomorulin在犬肾上皮细胞系（MDCK）上皮连接复合物形成中的作用。进行实验以确定是否特异性抑制uvomorulin功能将选择性地干扰顶端粘附小带（ZA）和闭合小带（ZO）的形成、稳定性或功能，或者是否它将干扰包括桥粒在内的所有形式的细胞间接触。阻断抗体和Fab片段对uvomorulin的连接复合物的形成的影响进行了检查与从头连接组装的Ca 2+开关测定。ZO，ZA，和桥粒的形成进行了测定通过荧光染色与紧密连接特异性蛋白ZO-1的抗体，与罗丹明鬼笔环肽ZA相关的肌动蛋白丝，并与抗桥粒斑蛋白抗体，分别。在不同的抗体处理条件和时间下，对每个连接元件形成的抑制程度非常相似。细胞最终克服抗体的抑制作用并形成连接的能力与细胞-细胞接触区域的uvomorulin的再现相关。因此，uvomorulin似乎介导上皮细胞之间的早期粘附事件，这是连接复合物的所有元件组装的先决条件。相比之下，用各种抗体或Fab片段处理对在过滤器上生长的汇合的、良好建立的MDCK细胞单层的跨上皮电阻没有很大影响。用多克隆α-uvomorulin IgG观察到的抗性的小的瞬时降低可能是由于连接复合物的更微妙的调节。
The role of the epithelial adhesion molecule uvomorulin in the formation of the epithelial junctional complex in the Madin-Darby canine kidney (MDCK) cell line was investigated. Experiments were carried out to determine whether specific inhibition of uvomorulin function would interfere selectively with the formation, stability, or function of the apical zonula adherens (ZA) and zonula occludens (ZO), or whether it would interfere with all forms of intercellular contact including the desmosomes. The effects of blocking antibodies and Fab fragments to uvomorulin on the formation of the junctional complex was examined with a Ca2+ switch assay for de novo junction assembly. The formation of the ZO, the ZA, and the desmosomes was assayed by fluorescence staining with an antibody to the tight junction-specific protein ZO-1, with rhodamine-phalloidin for ZA-associated actin filaments, and with an anti-desmoplakin antibody, respectively. Under different conditions and times of antibody treatment the extent of inhibition of the formation of each of the junctional elements was very similar. The ability of the cells to eventually overcome the inhibitory effect of the antibodies and form junctions correlated with the reappearance of uvomorulin at the regions of cell-cell contact. Therefore uvomorulin seems to mediate an early adhesion event between epithelial cells that is a prerequisite for the assembly of all elements of the junctional complex. In contrast, the transepithelial electrical resistance of confluent, well-established monolayers of MDCK cells grown on filters was not greatly affected by treatment with the various antibodies or Fab fragments. A small transient decrease in resistance observed with the polyclonal alpha-uvomorulin IgG may be due to a more subtle modulation of the junctional complex.