Besides the ubiquitin-proteasome system, autophagy is a major degradation pathway within cells. It delivers invading pathogens, damaged organelles, aggregated proteins, and other macromolecules from the cytosol to the lysosome for bulk degradation. This so-called canonical autophagy activity contributes to the maintenance of organelle, protein, and metabolite homeostasis as well as innate immunity. Over the past years, numerous studies rapidly deepened our knowledge on the autophagy machinery and its regulation, driven by the fact that impairment of autophagy is associated with several human pathologies, including cancer, immune diseases, and neurodegenerative disorders. Unexpectedly, components of the autophagic machinery were also found to participate in various processes that do not involve lysosomal delivery of cytosolic constituents. These functions are defined as noncanonical autophagy. Regarding neurodegenerative diseases, most research was performed in neurons, while for a long time, microglia received considerably less attention. Concomitant with the notion that microglia greatly contribute to brain health, the understanding of the role of autophagy in microglia expanded. To facilitate an overview of the current knowledge, here we present the fundamentals as well as the recent advances of canonical and noncanonical autophagy functions in microglia.

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小胶质细胞中的典型和非典型自噬途径

除了泛素-蛋白酶体系统，自噬是细胞内的主要降解途径。它将入侵的病原体、受损的细胞器、聚集的蛋白质和其他大分子从胞质溶胶输送到溶酶体以进行大量降解。这种所谓的典型自噬活动有助于维持细胞器、蛋白质和代谢物稳态以及先天免疫。在过去几年中，许多研究迅速加深了我们对自噬机制及其调控的认识，这是由于自噬受损与多种人类病理学相关，包括癌症、免疫疾病和神经退行性疾病。出乎意料的是，还发现自噬机制的组件参与各种不涉及胞质成分溶酶体递送的过程。这些功能被定义为非典型自噬。关于神经退行性疾病，大多数研究都是在神经元中进行的，而长期以来，小胶质细胞受到的关注要少得多。随着小胶质细胞极大地促进大脑健康的观念，对自噬在小胶质细胞中的作用的理解得到了扩展。为了促进对当前知识的概述，我们在这里介绍小胶质细胞中典型和非典型自噬功能的基本原理以及最新进展。扩大了对自噬在小胶质细胞中的作用的理解。为了促进对当前知识的概述，我们在这里介绍小胶质细胞中典型和非典型自噬功能的基本原理以及最新进展。扩大了对自噬在小胶质细胞中的作用的理解。为了促进对当前知识的概述，我们在这里介绍小胶质细胞中典型和非典型自噬功能的基本原理以及最新进展。