摘要
巨自噬/自噬是一种进化上保守的细胞内降解途径,可维持细胞稳态。在过去的二十年里,一系列的科学突破帮助解释了自噬相关的分子机制和生理功能。这一巨大进步在很大程度上继续依赖于强大的研究方法,特别是各种基于自噬标记 Atg8-PE 蛋白的方法,用于研究膜动力学和监测自噬活性。最近,已经成功开发了几种生化方法来在体外生产脂化蛋白 Atg8-PE 或其模拟物,包括酶介导的重构系统、化学成分确定的重构系统、无细胞脂化系统和蛋白质化学合成。这些方法对 Atg8 介导的膜动力学和蛋白质-蛋白质相互作用的潜在机制提供了重要的见解,为自噬研究开辟了新的视角。在这篇综述中,我们全面总结了基于 Atg8–PE 蛋白的体外生化方法和最新进展,以促进更好地理解自噬机制。此外,我们强调了各种基于 Atg8–PE 蛋白的方法的优缺点,为它们在自噬研究中的应用提供了一般指导。
缩写: ATG:自噬相关;ATP:三磷酸腺苷;COPII:外壳蛋白复合物 II;DGS-NTA:1,2-二油酰-sn-甘油-3-[(N-(5-氨基-1-羧基戊基)亚氨基二乙酸)琥珀酰](镍盐);DPPE:1,2-二棕榈酰-sn-甘油-3-磷酸乙醇胺;DSPE:1,2-二硬脂酰-sn-甘油-3-磷酸乙醇胺;大肠杆菌:大肠杆菌; EPL:表达蛋白连接;ERGIC:ER-高尔基中间室;GABARAP:GABA A 型受体相关蛋白;GABARAPL1:GABA A 型受体相关蛋白 like 1;GABARAPL2:GABA A 型受体相关蛋白 2;GFP:绿色荧光蛋白;GUVs:巨大的单层囊泡;LIR:LC3相互作用区;MAP1LC3/LC3:微管相关蛋白 1 轻链 3;MBP:麦芽糖结合蛋白;MEFs:小鼠胚胎成纤维细胞;MESNa:2-巯基乙磺酸钠盐;NCL:天然化学连接;NTA:次氮基三乙酸;PE:磷脂酰乙醇胺;PS:磷脂酰丝氨酸;PtdIns3K:III 类磷脂酰肌醇 3-激酶;PtdIns3P:磷脂酰肌醇-3-磷酸;SPPS:固相肽合成;TEV:烟草蚀纹病毒;WT:野生型。
"点击查看英文标题和摘要"
Atg8–PE protein-based in vitro biochemical approaches to autophagy studies
ABSTRACT
Macroautophagy/autophagy is an evolutionarily conserved intracellular degradation pathway that maintains cellular homeostasis. Over the past two decades, a series of scientific breakthroughs have helped explain autophagy-related molecular mechanisms and physiological functions. This tremendous progress continues to depend largely on powerful research methods, specifically, various autophagy marker Atg8–PE protein-based methods for studying membrane dynamics and monitoring autophagic activity. Recently, several biochemical approaches have been successfully developed to produce the lipidated protein Atg8–PE or its mimics in vitro, including enzyme-mediated reconstitution systems, chemically defined reconstitution systems, cell-free lipidation systems and protein chemical synthesis. These approaches have contributed important insights into the mechanisms underlying Atg8-mediated membrane dynamics and protein-protein interactions, creating a new perspective in autophagy studies. In this review, we comprehensively summarize Atg8–PE protein-based in vitro biochemical approaches and recent advances to facilitate a better understanding of autophagy mechanisms. In addition, we highlight the advantages and disadvantages of various Atg8–PE protein-based approaches to provide general guidance for their use in studying autophagy.
Abbreviations: ATG: autophagy related; ATP: adenosine triphosphate; COPII: coat protein complex II; DGS-NTA: 1,2-dioleoyl-sn-glycero-3-[(N-(5-amino-1-carboxypentyl)iminodiacetic acid)succinyl] (nickel salt); DPPE: 1,2-dipalmitoyl-sn-glycero-3-phosphoethanolamine; DSPE: 1,2-distearoyl-sn-glycero-3-phosphoethanolamine; E. coli: Escherichia coli; EPL: expressed protein ligation; ERGIC: ER-Golgi intermediate compartment; GABARAP: GABA type A receptor-associated protein; GABARAPL1: GABA type A receptor associated protein like 1; GABARAPL2: GABA type A receptor associated protein like 2; GFP: green fluorescent protein; GUVs: giant unilamellar vesicles; LIR: LC3-interacting region; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; MBP: maltose binding protein; MEFs: mouse embryonic fibroblasts; MESNa: 2-mercaptoethanesulfonic acid sodium salt; NCL: native chemical ligation; NTA: nitrilotriacetic acid; PE: phosphatidylethanolamine; PS: phosphatidylserine; PtdIns3K: class III phosphatidylinositol 3-kinase; PtdIns3P: phosphatidylinositol-3-phosphate; SPPS: solid-phase peptide synthesis; TEV: tobacco etch virus; WT: wild-type.