MRC Laboratory for Molecular Cell Biology, University College London, Gower Street, London WC1E 6BT, UK.
MRC Laboratory for Molecular Cell Biology, University College London, Gower Street, London WC1E 6BT, UK
J Cell Sci. 2018 Mar 26;131(6):jcs207779. doi: 10.1242/jcs.207779.
In epithelial cells, apical exclusion of Bazooka (the Par3 protein) defines the position of the zonula adherens (ZA), which demarcates the apical and lateral membrane and allows cells to assemble into sheets. Here, we show that the small GTPase Rap1, its effector Canoe (Cno) and the Cdc42 effector kinase Mushroom bodies tiny (Mbt), converge in regulating epithelial morphogenesis by coupling stabilization of the adherens junction (AJ) protein E-Cadherin and Bazooka retention at the ZA. Furthermore, our results show that the localization of Rap1, Cno and Mbt at the ZA is interdependent, indicating that their functions during ZA morphogenesis are interlinked. In this context, we find the Rap1-GEF Dizzy is enriched at the ZA and our results suggest that it promotes Rap1 activity during ZA morphogenesis. Altogether, we propose the Dizzy, Rap1 and Cno pathway and Mbt converge in regulating the interface between Bazooka and AJ material to promote ZA morphogenesis.
在 上皮细胞中,Bazooka(Par3 蛋白)的顶端排除定义了黏着带(ZA)的位置,ZA 划分了顶端和侧膜,并允许细胞组装成薄片。在这里,我们表明小 GTPase Rap1、其效应因子 Canoe(Cno)和 Cdc42 效应激酶 Mushroom bodies tiny(Mbt)通过稳定黏着连接蛋白 E-Cadherin 和将 Bazooka 保留在 ZA 来集中调节上皮形态发生。此外,我们的结果表明,Rap1、Cno 和 Mbt 在 ZA 的定位是相互依赖的,这表明它们在 ZA 形态发生过程中的功能是相互关联的。在这种情况下,我们发现 Rap1-GEF Dizzy 在 ZA 中富集,我们的结果表明它在 ZA 形态发生过程中促进 Rap1 活性。总的来说,我们提出 Dizzy、Rap1 和 Cno 途径以及 Mbt 集中调节 Bazooka 和 AJ 物质之间的界面,以促进 ZA 形态发生。