Caenorhabditis elegans auxilin:: a J-domain protein essential for clathrin-mediated endocytosis in vivo
Caenorhabditis elegans auxilin:: a J-domain protein essential for clathrin-mediated endocytosis in vivo
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DOI：
10.1038/35055137
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发表时间：
2001-02-01
影响因子：
21.3
通讯作者：
Eisenberg, E
中科院分区：
文献类型：
--
作者：
Greener, T;Grant, B;Eisenberg, E
网格蛋白包被囊泡的出芽对蛋白质的运输至关重要。出芽后，在囊泡与其他膜结构融合之前，必须将网格蛋白剥离。在体外，分子伴侣Hsc70在atp依赖的过程中揭开网格蛋白包被的囊泡，该过程需要特定的j结构域蛋白，如辅助蛋白。然而，很少有证据表明Hsc70或auxilin在体内是必需的。在这里，我们发现秀丽隐杆线虫有一个单一的辅助素同源物，其体外活性与哺乳动物的辅助素相同。当使用rna介导的干扰（RNAi）抑制秀丽隐杆线虫中auxilin的表达时，卵母细胞中绿色荧光蛋白（GFP）标记的蛋黄蛋白的受体介导的内吞作用明显减少。此外，通过光漂白后荧光恢复（FRAP）测定，这些蠕虫在幼虫发育过程中大多停滞，在许多细胞类型中表现出gfp -网格蛋白分布缺陷，并且网格蛋白动力学表现出明显的变化。我们得出结论，辅助素是秀丽隐杆线虫体内网格蛋白介导的内吞作用和发育所必需的。
The budding of clathrin-coated vesicles is essential for protein transport. After budding, clathrin must be uncoated before the Vesicles can fuse with other membranous structures. In vitro, the molecular chaperone Hsc70 uncoats clathrin-coated vesicles in an ATP-dependent process that requires a specific J-domain protein such as auxilin. However, there is little evidence that either Hsc70 or auxilin is essential in vivo. Here we show that C. elegans has a single auxilin homologue that is identical to mammalian auxilin in its in vitro activity. When RNA-mediated interference (RNAi) is used to inhibit auxilin expression in C. elegans, oocytes show markedly reduced receptor-mediated endocytosis of yolk protein tagged with green fluorescent protein (GFP). In addition, most of these worms arrest during larval development, exhibit defective distribution of GFP-clathrin in many cell types, and show a marked change in clathrin dynamics, as determined by fluorescence recovery after photobleaching (FRAP). We conclude that auxilin is required for in vivo clathrin-mediated endocytosis and development in C. elegans.