Regulatory mechanisms of protein sorting in post-Golgi membrane trafficking

尽管发育过程以及生物和非生物与环境的相互作用需要受体及其配体、转运体和膜融合效应器的调节传递到质膜或从质膜提取，但植物细胞高尔基体后内膜系统的膜运输仍然知之甚少。这项提案的主要目标是确定后高尔基体贩运中蛋白质分类的监管机制。重点将集中在参与囊泡形成、货物选择或囊泡与靶膜融合的五个蛋白质家族的成员：调节ARF GTP酶活性的鸟嘌呤核苷酸交换因子(ARF-GEF)、其ARF底物、介导货物分选形成囊泡的适配蛋白(AP)复合体的μ-Adaptin亚单位，以及Rab GTP酶和合成素，两者都有助于膜融合的特异性。实验方法包括亚细胞蛋白质定位，对蛋白质功能的遗传或实验干扰，以及分析可溶性和膜结合的货物在正常和中断的路径中的运输。预期的结果还将为社区提供新的资源，如细胞内蛋白质定位的标记。

Membrane trafficking in the post-Golgi endomembrane system of plant cells is still poorly understood, although developmental processes as well as biotic and abiotic interactions with the environment require regulated delivery to and retrieval from the plasma membrane of receptors and their ligands, transporters and membrane-fusion effectors. The main goal of this proposal is to identify regulatory mechanisms underlying protein sorting in post-Golgi trafficking. The focus will be on members of five protein families involved in vesicle formation, cargo selection or vesicle fusion with target membranes: guanine-nucleotide exchange factors regulating ARF GTPase activity (ARF-GEFs), their ARF substrates, the μ-adaptin subunits of adaptor protein (AP) complexes mediating cargo sorting into forming vesicles, and Rab GTPases and syntaxins both of which contribute to the specificity of membrane fusion. The experimental approaches include subcellular protein localisation, genetic or experimental interference with protein function, and analysis of trafficking of soluble and membrane-bound cargo in normal and disrupted pathways. The anticipated results will also provide the community with new resources such as markers for intracellular protein localisation.