Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, USA
Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, USA.
Biol Open. 2021 Feb 3;10(2):bio055640. doi: 10.1242/bio.055640.
Regulation of cell architecture is critical in the formation of tissues during animal development. The mechanisms that control cell shape must be both dynamic and stable in order to establish and maintain the correct cellular organization. Previous work has identified Shroom family proteins as essential regulators of cell morphology during vertebrate development. Shroom proteins regulate cell architecture by directing the subcellular distribution and activation of Rho-kinase, which results in the localized activation of non-muscle myosin II. Because the Shroom-Rock-myosin II module is conserved in most animal model systems, we have utilized to further investigate the pathways and components that are required for Shroom to define cell shape and tissue architecture. Using a phenotype-based heterozygous F1 genetic screen for modifiers of Shroom activity, we identified several cytoskeletal and signaling protein that may cooperate with Shroom. We show that two of these proteins, Enabled and Short stop, are required for ShroomA-induced changes in tissue morphology and are apically enriched in response to Shroom expression. While the recruitment of Ena is necessary, it is not sufficient to redefine cell morphology. Additionally, this requirement for Ena appears to be context dependent, as a variant of Shroom that is apically localized, binds to Rock, but lacks the Ena binding site, is still capable of inducing changes in tissue architecture. These data point to important cellular pathways that may regulate contractility or facilitate Shroom-mediated changes in cell and tissue morphology.
细胞结构的调节在动物发育过程中组织的形成中至关重要。控制细胞形状的机制必须既具有动态性又具有稳定性，才能建立和维持正确的细胞组织。先前的工作已经确定 Shroom 家族蛋白是脊椎动物发育过程中细胞形态的重要调节因子。Shroom 蛋白通过指导 Rho-kinase 的亚细胞分布和激活来调节细胞结构，从而导致非肌肉肌球蛋白 II 的局部激活。由于 Shroom-Rock-myosin II 模块在大多数动物模型系统中都保守，我们利用 进一步研究了 Shroom 定义细胞形状和组织形态所必需的途径和成分。通过基于表型的 Shroom 活性杂合 F1 遗传筛选，我们鉴定出几种细胞骨架和信号蛋白可能与 Shroom 合作。我们表明，这两种蛋白质，Enabled 和 Short stop，是 ShroomA 诱导的组织形态变化所必需的，并且响应 Shroom 表达在上部富集。虽然 Ena 的募集是必要的，但不足以重新定义细胞形态。此外，这种对 Ena 的需求似乎是上下文相关的，因为一种顶端定位的、与 Rock 结合但缺乏 Ena 结合位点的 Shroom 变体仍然能够诱导组织架构的变化。这些数据指向可能调节收缩性或促进 Shroom 介导的细胞和组织形态变化的重要细胞途径。
