ESCRT-dependent vacuolar sorting and degradation of the auxin biosynthetic enzyme YUC1 flavin monooxygenase
ESCRT-dependent vacuolar sorting and degradation of the auxin biosynthetic enzyme YUC1 flavin monooxygenase
复制标题
生长素生物合成酶 YUC1 黄素单加氧酶的 ESCRT 依赖性液泡分选和降解。
DOI：
10.1111/jipb.12760
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发表时间：
2019-09-01
影响因子：
11.4
通讯作者：
Zhao, Yunde
中科院分区：
文献类型：
--
作者：
Ge, Chennan;Gao, Caiji;Zhao, Yunde
YUC黄素单加氧酶催化生长素生物合成的限速步骤。在这里，我们报告了GFP-YUC1的空泡靶向和降解。在拟南芥原生质体或转基因植株中表达的GFP-YUC1融合基因主要定位于液泡中。令人惊讶的是，我们发现GFP-YUC1是一种可溶性蛋白质，通过ESCRT途径被分类到空泡中，这一途径长期以来一直被认为是分类和靶向完整膜蛋白的途径。我们进一步表明，GFP-YUC1是泛素化的，在这种形式下，GFP-YUC1被作为降解的目标，这一过程也受到生长素水平升高的刺激。我们的发现揭示了GFP-YUC1降解的分子机制，并证明ESCRT途径可以识别可溶的和完整的膜蛋白作为货物。
YUC flavin monooxygenases catalyze the rate-limiting step of auxin biosynthesis. Here we report the vacuolar targeting and degradation of GFP-YUC1. GFP-YUC1 fusion expressed in Arabidopsis protoplasts or transgenic plants was primarily localized in vacuoles. Surprisingly, we established that GFP-YUC1, a soluble protein, was sorted to vacuoles through the ESCRT pathway, which has long been recognized for sorting and targeting integral membrane proteins. We further show that GFP-YUC1 was ubiquitinated and in this form GFP-YUC1 was targeted for degradation, a process that was also stimulated by elevated auxin levels. Our findings revealed a molecular mechanism of GFP-YUC1 degradation and demonstrate that the ESCRT pathway can recognize both soluble and integral membrane proteins as cargoes.