Eukaryotic organisms share many common features in terms of endomembrane trafficking. This fact has helped plant scientists to propose testable hypotheses on how plant intracellular membrane trafficking is achieved and regulated based on knowledge from yeast and mammals. However, when a new compartment has been identified in a plant cell that has a vesicle tethering complex located at a position which is completely different to its counterpart in yeast and mammalian cells, caution is demanded when interpreting possible interactions with other trafficking elements. This is exemplified by the recently discovered EMAC (ER and microtubule-associated compartment). It has been postulated that this compartment is the recipient of vacuolar sorting receptors (VSRs) transported retrogradely via “retromer vesicles” from a post-Golgi location. Unfortunately, this suggestion was based entirely on our knowledge of retromer from yeast and mammalian cells, and did not take into account the available literature on the composition, localization, and function of the plant retromer. It also lacked reference to recent contradictory findings on VSR trafficking. In this short article, we have tried to rectify this situation, pointing out that plant retromer may not function as a pentameric complex of two subunits: the retromer core and the sorting nexins.

中文翻译：

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EMAC、Retromer 和 VSR：它们是否连接？

真核生物在内膜运输方面具有许多共同特征。这一事实帮助植物科学家根据酵母和哺乳动物的知识提出了关于植物细胞内膜运输如何实现和调节的可检验假设。然而，当在植物细胞中发现一个新的隔室时，该植物细胞的囊泡束缚复合物位于与酵母和哺乳动物细胞中的对应物完全不同的位置，在解释与其他运输元素可能的相互作用时需要谨慎。最近发现的 EMAC（ER 和微管相关隔室）就是例证。据推测，该隔室是通过“逆向囊泡”从高尔基体后位置逆行运输的液泡分选受体 (VSR) 的受体。很遗憾，这一建议完全基于我们对酵母和哺乳动物细胞逆转录酶的了解，并未考虑有关植物逆转录酶的组成、定位和功能的现有文献。它还没有提及最近关于 VSR 贩运的相互矛盾的调查结果。在这篇简短的文章中，我们试图纠正这种情况，指出植物逆转录酶可能无法作为两个亚基的五聚体复合物发挥作用：逆转录酶核心和分选连接蛋白。