The Rab11 effectors Fip5 and Fip1 regulate zebrafish intestinal development.
The Rab11 effectors Fip5 and Fip1 regulate zebrafish intestinal development.
复制标题
Rab11效应子Fip5和Fip1调节斑马鱼肠道发育。
DOI：
10.1242/bio.055822
复制
发表时间：
2020-10-23
期刊：
影响因子：
2.4
通讯作者：
Prekeris R
中科院分区：
文献类型：
--
作者：
Jewett CE;Appel BH;Prekeris R
Rab11 顶端再循环内体途径是极性和管腔形成的成熟调节剂；然而，Rab11 囊泡运输还指导多种其他细胞过程，这就提出了 Rab11 囊泡如何实现货物传递的空间、时间和内容特异性的问题。在某种程度上，这种特异性是通过效应蛋白实现的，但 Rab11 效应蛋白在体内的作用仍然模糊。在这里，我们使用 CRISPR/Cas9 基因编辑来研究 Rab11 效应器 Fip5 在斑马鱼肠道发育过程中的作用。斑马鱼含有两个旁系同源基因 fip5a 和 fip5b，它们是人类 FIP5 的直系同源基因。我们发现fip5a和fip5b突变鱼表现出微绒毛包涵体病的特征表型，包括微绒毛缺陷和溶酶体积累。单突变体和双突变体分析表明，fip5a 和 fip5b 并行发挥作用，并调节末端网组装角蛋白所需的运输途径。值得注意的是，在某些遗传背景下，Fip5 的缺失会触发密切相关的家族成员 Fip1 的蛋白质上调。这种补偿机制发生在斑马鱼肠道发育过程中和管腔发生的组织培养模型中。总之，我们的数据表明 Rab11 效应器 Fip5 和 Fip1 参与顶端微绒毛形成所需的运输途径。摘要：Rab11 效应器 fip5a 和 fip5b 在斑马鱼肠道发育过程中并行调节顶端运输和微绒毛建立。此外，细胞上调 Fip1 以补偿 Fip5 的损失。
The Rab11 apical recycling endosome pathway is a well-established regulator of polarity and lumen formation; however, Rab11-vesicular trafficking also directs a diverse array of other cellular processes, raising the question of how Rab11 vesicles achieve specificity in space, time and content of cargo delivery. In part, this specificity is achieved through effector proteins, yet the role of Rab11 effector proteins in vivo remains vague. Here, we use CRISPR/Cas9 gene editing to study the role of the Rab11 effector Fip5 during zebrafish intestinal development. Zebrafish contain two paralogous genes, fip5a and fip5b, that are orthologs of human FIP5. We find that fip5a- and fip5b-mutant fish show phenotypes characteristic of microvillus inclusion disease, including microvilli defects and lysosomal accumulation. Single and double mutant analyses suggest that fip5a and fip5b function in parallel and regulate trafficking pathways required for assembly of keratin at the terminal web. Remarkably, in some genetic backgrounds, the absence of Fip5 triggers protein upregulation of a closely related family member, Fip1. This compensation mechanism occurs both during zebrafish intestinal development and in tissue culture models of lumenogenesis. In conclusion, our data implicate the Rab11 effectors Fip5 and Fip1 in a trafficking pathway required for apical microvilli formation. Summary: The Rab11 effectors fip5a and fip5b function in parallel to regulate apical trafficking and microvilli establishment during zebrafish intestinal development. Moreover, cells upregulate Fip1 to compensate for loss of Fip5.