SNARE proteins VAMP721 and VAMP722 mediate the post-Golgi trafficking required for auxin-mediated development in Arabidopsis
SNARE proteins VAMP721 and VAMP722 mediate the post-Golgi trafficking required for auxin-mediated development in Arabidopsis
复制标题
SNARE 蛋白 VAMP721 和 VAMP722 介导拟南芥生长素介导的发育所需的后高尔基体运输
DOI：
10.1111/tpj.15450
复制
发表时间：
2021
期刊：
影响因子：
7.2
通讯作者：
Lin Jinxing
中科院分区：
文献类型：
--
作者：
Zhang Liang;Ma Jingwen;Liu Huan;Yi Qian;Wang Yanan;Xing Jingjing;Zhang Peipei;Ji Shengdong;Li Mingjun;Li Jingyuan;Shen Jinbo;Lin Jinxing
植物激素生长素控制植物发育的许多方面。生长素转运蛋白的极性定位是通过分泌、胞吞和再循环等膜运输过程来调节的，从而形成生长素浓度梯度。在这里，我们研究了拟南芥R-SNARE囊泡相关膜蛋白721（VAMP 721）和VAMP 722在高尔基体后运输中的功能，这些运输是生长素分布和幼苗生长所必需的。我们发现，多个生长表型，如子叶发育，静脉图案和侧根生长，是缺陷的双homohomorousvamp 721 vamp 722突变体。在突变体幼苗中还观察到生长素分布异常和根构型异常。荧光成像显示，三种生长素转运蛋白PIN-FORMED 1（PIN 1）、PIN 2和生长素抗性1（AUX 1）异常地积累在双突变体的细胞质内，损害质膜（PM）的极性定位。对细胞内运输的分析表明，VAMP 721和VAMP 722参与了FM 4 - 64的内吞作用以及PIN 2转运蛋白的分泌和再循环至PM，但不参与其向液泡的运输。此外，vamp 721 vamp 722突变体根显示扩大的trans-Golgi网络（TGN）结构，如各种标记蛋白的亚细胞定位和透射电子显微镜观察到的超微结构所示。因此，我们的研究结果表明，R-SNARE VAMP 721和VAMP 722介导生长素转运蛋白从TGN亚结构域到PM的高尔基体后运输，对植物生长有重大贡献。
The plant hormone auxin controls many aspects of plant development. Membrane trafficking processes, such as secretion, endocytosis and recycling, regulate the polar localization of auxin transporters in order to establish an auxin concentration gradient. Here, we investigate the function of theArabidopsis thalianaR‐SNAREs VESICLE‐ASSOCIATED MEMBRANE PROTEIN 721 (VAMP721) and VAMP722 in the post‐Golgi trafficking required for proper auxin distribution and seedling growth. We show that multiple growth phenotypes, such as cotyledon development, vein patterning and lateral root growth, were defective in the double homozygousvamp721 vamp722 mutant. Abnormal auxin distribution and root patterning were also observed in the mutant seedlings. Fluorescence imaging revealed that three auxin transporters, PIN‐FORMED 1 (PIN1), PIN2 and AUXIN RESISTANT 1 (AUX1), aberrantly accumulate within the cytoplasm of the double mutant, impairing the polar localization at the plasma membrane (PM). Analysis of intracellular trafficking demonstrated the involvement of VAMP721 and VAMP722 in the endocytosis of FM4‐64 and the secretion and recycling of the PIN2 transporter protein to the PM, but not its trafficking to the vacuole. Furthermore,vamp721 vamp722mutant roots display enlargedtrans‐Golgi network (TGN) structures, as indicated by the subcellular localization of a variety of marker proteins and the ultrastructure observed using transmission electron microscopy. Thus, our results suggest that the R‐SNAREs VAMP721 and VAMP722 mediate the post‐Golgi trafficking of auxin transporters to the PM from the TGN subdomains, substantially contributing to plant growth.