Li Dan, Song Jing-Zhen, Li Hui, Shan Mei-Hua, Liang Yongheng, Zhu Jing, Xie Zhiping
School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, PR China.
College of Life Sciences, Nanjing Agricultural University, Nanjing, PR China.
FEBS Lett. 2015 Jan 16;589(2):269-76. doi: 10.1016/j.febslet.2014.11.050. Epub 2014 Dec 12.
Nitrogen starvation is a universal stimulus of autophagy. At present, little is known about the relationship between carbon metabolism and autophagy under nitrogen starvation. Here, we show that yeast cells continue to consume glucose and downregulate fermentation under nitrogen starvation. Storage lipid production is increased, with concurrent proliferation of lipid droplets. Furthermore, we provide evidence that triacylglycerol synthesis is crucial for autophagosome biogenesis. It is involved in a step downstream of PAS (phagophore assembly site) scaffold assembly, and upstream of the recruitment of Atg1, Atg14, Atg5 and Atg8. Finally, we demonstrate that lipid droplets transiently interact with Atg8-containing membranes. Our study reveals a novel connection linking neutral lipid metabolism, lipid droplets and autophagy.
氮饥饿是自噬的一种普遍刺激因素。目前，关于氮饥饿条件下碳代谢与自噬之间的关系知之甚少。在此，我们表明酵母细胞在氮饥饿条件下会持续消耗葡萄糖并下调发酵作用。储存脂质的产量增加，同时脂滴大量增殖。此外，我们提供的证据表明三酰甘油合成对于自噬体的生物发生至关重要。它参与吞噬泡组装位点（PAS）支架组装下游以及Atg1、Atg14、Atg5和Atg8募集上游的一个步骤。最后，我们证明脂滴与含有Atg8的膜发生短暂相互作用。我们的研究揭示了中性脂质代谢、脂滴与自噬之间的一种新联系。
