Department of Biological Sciences, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Korea.
These authors contributed equally to this work.
Mol Cells. 2021 Mar 31;44(3):168-178. doi: 10.14348/molcells.2021.0027.
The retinal pigment epithelium (RPE) forms a monolayer sheet separating the retina and choroid in vertebrate eyes. The polarized nature of RPE is maintained by distributing membrane proteins differentially along apico-basal axis. We found the distributions of these proteins differ in embryonic, post-natal, and mature mouse RPE, suggesting developmental regulation of protein trafficking. Thus, we deleted tumor 101 (), a key component of endosomal sorting complexes required for transport (ESCRT), in embryonic and mature RPE to determine whether ESCRT-mediated endocytic protein trafficking correlated with the establishment and maintenance of RPE polarity. Loss of severely disturbed the polarity of RPE, which forms irregular aggregates exhibiting non-polarized distribution of cell adhesion proteins and activation of epidermal growth factor receptor signaling. These findings suggest that ESCRT-mediated protein trafficking is essential for the development and maintenance of RPE cell polarity.
视网膜色素上皮 (RPE) 在脊椎动物的眼睛中形成一层分离视网膜和脉络膜的单层薄片。RPE 的极化性质通过在顶-基底轴上差异分布膜蛋白来维持。我们发现这些蛋白质在胚胎期、出生后和成熟的小鼠 RPE 中的分布不同，这表明蛋白质运输的发育调控。因此，我们在胚胎期和成熟的 RPE 中删除了肿瘤 101()，这是内体分选复合物必需的运输 (ESCRT) 的关键组成部分，以确定 ESCRT 介导的内吞蛋白运输是否与 RPE 极性的建立和维持相关。缺失严重扰乱了 RPE 的极性，RPE 形成不规则聚集，表现出细胞粘附蛋白的非极化分布和表皮生长因子受体信号的激活。这些发现表明 ESCRT 介导的蛋白质运输对于 RPE 细胞极性的发育和维持至关重要。
