PDF(Pubmed)
Abstract：
Macroautophagy/autophagy is a strategy cells use to cope with detrimental conditions, e.g. nutrient deficiency. Phagophores, the precursors to autophagosomes, are initiated and expanded on the endoplasmic reticulum (ER). However, how phagophores and completed autophagosomes are linked to the ER remains incompletely understood. We recently unveiled a RAB GTPase-based linkage between the two structures. RABC1 is a plant member of RABC/RAB18 GTPases. Our biochemical and microscopy data indicated that RABC1 promotes autophagy in response to nutrient starvation, but not under ER stress. Under nutrient-starvation conditions, active RABC1 interacts with ATG18a on the ER, controlling the association of ATG18a to the ER. Subsequently, active RABC1 is turned off allowing expanded phagophores or autophagosomes to detach from the ER. Our work identifies a RAB GTPase-mediated autophagy process in plant cells, opening a door for improving crop productivity in the changing environment.
摘要：
巨自噬/自噬是细胞用来应对有害条件的策略，例如营养缺乏。吞噬细胞,自噬体的前体，在内质网（ER）上启动和扩展。然而,吞噬细胞和完整的自噬体是如何与内质网连接的,目前尚不完全清楚.我们最近公布了两个结构之间的基于RABGTPase的连接。RABC1是RABC/RAB18GTPases的植物成员。我们的生化和显微镜数据表明，RABC1促进自噬响应营养饥饿，但不是在ER压力下。在营养饥饿的条件下，活性RABC1与ER上的ATG18a相互作用，控制ATG18a与ER的关联。随后，活性RABC1被关闭,允许扩大的吞噬团或自噬体从ER分离。我们的工作确定了植物细胞中RABGTP酶介导的自噬过程，为在不断变化的环境中提高作物生产力打开一扇门。
