ROCK-mediated contractility, tight junctions and channels contribute to the conversion of a preapical patch into apical surface during isochoric lumen initiation
ROCK-mediated contractility, tight junctions and channels contribute to the conversion of a preapical patch into apical surface during isochoric lumen initiation
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DOI：
10.1242/jcs.018648
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发表时间：
2008-11-01
影响因子：
4
通讯作者：
Kroschewski, Ruth
中科院分区：
文献类型：
--
作者：
Ferrari, Aldo;Veligodskiy, Alexey;Kroschewski, Ruth
上皮细胞聚集成三维聚集体，形成含有管腔的器官亚结构。其中的细胞与基底面接触细胞外基质，相邻细胞与其接触面接触，管腔与其顶端表面接触。我们使用定量活细胞成像技术研究了单个MDCK细胞发育成具有管腔的聚集体的过程，以确定管腔形成的形态发生规律。在两细胞聚集体中，膜插入接触面形成了以顶端标记gp135、微绒毛的存在和E-钙粘附素缺失为特征的尖前补丁(PAP)。这种PAP起源于一个具有心尖循环内小体特征的隔室，并通过Brefeldin-A敏感的膜运输和在其周围建立紧密连接而成熟。由于水和离子通道的活动，形成了光学可分辨的管腔。最初，管腔扩大，但不改变总体积或细胞数量，但细胞体积减少。此外，ROCK1/2-肌球蛋白-II通路抑制了PAP和管腔的形成。因此，管腔的形成是PAP建立、PAP成熟、管腔启动和管腔扩大的结果。这些相与不同的细胞表面和体积模式相关，这表明这些形态计量参数受运输、岩石介导的收缩和静水压力调节，反之亦然。
Epithelial cells assemble into three-dimensional aggregates to generate lumen-containing organ substructures. Cells therein contact the extracellular matrix with their basal surface, neighbouring cells with their contact surface and the lumen with their apical surface. We investigated the development of single MDCK cells into aggregates with lumen using quantitative live-cell imaging to identify morphogenetic rules for lumen formation. In two-cell aggregates, membrane insertion into the contact surface established a preapical patch (PAP) characterized by the presence of the apical marker gp135, microvilli and the absence of E-cadherin. This PAP originated from a compartment that had hallmarks of an apical recycling endosome, and matured through Brefeldin-A-sensitive membrane trafficking and the establishment of tight junctions around itself. As a result of the activity of water and ion channels, an optically resolvable lumen formed. Initially, this lumen enlarged without changes in aggregate volume or cell number but with decreasing cell volumes. Additionally, the ROCK1/2-myosin-II pathway counteracted PAP and lumen formation. Thus, lumen formation results from PAP establishment, PAP maturation, lumen initiation and lumen enlargement. These phases correlate with distinct cell surface and volume patterns, which suggests that such morphometric parameters are regulated by trafficking, ROCK-mediated contractility and hydrostatic pressure or vice versa.