The process of cell migration is essential throughout life, driving embryonic morphogenesis and ensuring homeostasis in adults. Defects in cell migration are a major cause of human disease, with excessive migration causing autoimmune diseases and cancer metastasis, whereas reduced capacity for migration leads to birth defects and immunodeficiencies. Myriad studies in vitro have established a consensus view that cell migrations require cell polarization, Rho GTPase-mediated cytoskeletal rearrangements, and myosin-mediated contractility. However, in vivo studies later revealed a more complex picture, including the discovery that cells migrate not only as single units but also as clusters, strands, and sheets. In particular, the role of E-Cadherin in cell motility appears to be more complex than previously appreciated. Here, we discuss recent advances achieved by combining the plethora of genetic tools available to the Drosophila geneticist with live imaging and biophysical techniques. Finally, we discuss the emerging themes such studies have revealed and ponder the puzzles that remain to be solved.

中文翻译：

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果蝇单个和集体细胞迁移的细胞和分子机制：主题和变化。

细胞迁移过程在整个生命过程中都是必不可少的，它驱动胚胎形态发生并确保成人体内平衡。细胞迁移缺陷是人类疾病的主要原因，过度迁移会导致自身免疫性疾病和癌症转移，而迁移能力降低会导致出生缺陷和免疫缺陷。无数的体外研究已经建立了一个共识，即细胞迁移需要细胞极化、Rho GTPase 介导的细胞骨架重排和肌球蛋白介导的收缩性。然而，后来的体内研究揭示了一个更复杂的情况，包括发现细胞不仅以单个单元的形式迁移，而且还以簇、链和片的形式迁移。特别是，E-钙粘蛋白在细胞运动中的作用似乎比以前理解的更复杂。这里，我们讨论了通过将果蝇遗传学家可用的大量遗传工具与实时成像和生物物理技术相结合所取得的最新进展。最后，我们讨论了这些研究揭示的新兴主题，并思考了仍有待解决的难题。