During embryonic development and cancer metastasis, migratory cells must establish stable connections with new partners at their destinations. Here, we establish the Drosophila border cells as a model for this multistep process. During oogenesis, border cells delaminate from the follicular epithelium and migrate. When they reach their target, the oocyte, they undergo a stereotypical series of steps to adhere to it, then connect with another migrating epithelium. We identify gap-junction-forming innexin proteins as critical. Surprisingly, the channel function is dispensable. Instead, Innexins 2 and 3 function within the border cells, and Innexin 4 functions within the germline, to regulate microtubules. The microtubule-dependent border cell-oocyte interaction is essential to brace the cells against external morphogenetic forces. Thus, we establish an experimental model and use genetic, thermogenetic, and live-imaging approaches to uncover the contributions of Innexins and microtubules to a cell-biological process important in development and cancer.

在胚胎发育和癌症转移期间，迁移细胞必须与目的地的新伙伴建立稳定的联系。在这里，我们建立了果蝇边界细胞作为这个多步骤过程的模型。在卵子发生过程中，边界细胞从滤泡上皮分层并迁移。当它们到达目标卵母细胞时，它们会经历一系列刻板的步骤来粘附它，然后与另一个迁移的上皮细胞连接。我们认为形成间隙连接的 innexin 蛋白至关重要。令人惊讶的是，通道功能是可有可无的。相反，Innexin 2 和 3 在边界细胞内起作用，而 Innexin 4 在生殖系内起作用，以调节微管。依赖微管的边界细胞-卵母细胞相互作用对于支撑细胞抵抗外部形态发生力至关重要。因此，我们建立了一个实验模型，并使用遗传、热遗传、