Department of Molecular, Cell and Developmental Biology, University of California , Los Angeles, CA, USA.
Molecular Biology Institute, University of California , Los Angeles, CA, USA.
Autophagy. 2020 Jun;16(6):1145-1147. doi: 10.1080/15548627.2020.1739450. Epub 2020 Mar 21.
In contrast to stress-induced macroautophagy/autophagy that happens during nutrient deprivation and other environmental challenges, basal autophagy is thought to be an important mechanism that cells utilize for homeostatic purposes. For instance, basal autophagy is used to recycle damaged and malfunctioning organelles and proteins to provide the building blocks for the generation of new ones throughout life. In addition, specialized autophagic processes, such as lipophagy, the autophagy-induced breakdown of lipid droplets (LDs), and glycophagy (breakdown of glycogen), are employed to maintain proper energy levels in the cell. The importance of autophagy in the regulation of stem cell behavior has been the focus of recent studies. However, the upstream signals that control autophagic activity in stem cells and the precise role of autophagy in stem cells are only starting to be elucidated. In a recent publication, we described how the Egfr (epidermal growth factor receptor) pathway stimulates basal autophagy to support the maintenance of somatic cyst stem cells (CySCs) and to control lipid levels in the testis.
与营养缺乏和其他环境挑战时发生的应激诱导的巨自噬/自噬相反，基础自噬被认为是细胞用于维持体内平衡的重要机制。例如，基础自噬用于回收受损和功能失调的细胞器和蛋白质，为新的细胞器和蛋白质的生成提供构建块。此外，专门的自噬过程，如脂噬作用（脂质滴的自噬性分解）和糖噬作用（糖原的分解），被用来维持细胞内适当的能量水平。自噬在调节干细胞行为中的重要性一直是最近研究的焦点。然而，控制干细胞中自噬活性的上游信号以及自噬在干细胞中的精确作用才刚刚开始被阐明。在最近的一篇论文中，我们描述了表皮生长因子受体（Egfr）途径如何刺激基础自噬来支持体腔干细胞（CySCs）的维持，并控制睾丸中的脂质水平。
