Hargitai Dávid, Kenéz Lili, Al-Lami Muna, Szenczi Győző, Lőrincz Péter, Juhász Gábor
Department of Anatomy, Cell and Developmental Biology, Eötvös Loránd University, Budapest, Hungary.
Institute of Genetics, Biological Research Centre, Szeged, Hungary.
Front Cell Dev Biol. 2022 Oct 10;10:976882. doi: 10.3389/fcell.2022.976882. eCollection 2022.
Autophagy is a conserved catabolic process in eukaryotic cells that degrades intracellular components in lysosomes, often in an organelle-specific selective manner (mitophagy, ERphagy, etc). Cells also use autophagy as a defense mechanism, eliminating intracellular pathogens selective degradation known as xenophagy. is a Gram-negative intracellular bacterium, which is one of the most common parasites on Earth affecting approximately half of terrestrial arthropods. Interestingly, infection grants the host resistance against other pathogens and modulates lifespan, so this bacterium resembles an endosymbiont. Here we demonstrate that somatic cells normally degrade a subset of these bacterial cells, and autophagy is required for selective elimination of Wolbachia upon antibiotic damage. In line with these, Wolbachia overpopulates in autophagy-compromised animals during aging while its presence fails to affect host lifespan unlike in case of control flies. The autophagic degradation of Wolbachia thus represents a novel antibacterial mechanism that controls the propagation of this unique bacterium, behaving both as parasite and endosymbiont at the same time.
自噬是真核细胞中一种保守的分解代谢过程,它在溶酶体中降解细胞内成分,通常以一种细胞器特异性的选择性方式(线粒体自噬、内质网自噬等)进行。细胞还将自噬用作一种防御机制,通过称为异噬作用的选择性降解来清除细胞内病原体。沃尔巴克氏体是一种革兰氏阴性细胞内细菌,是地球上最常见的寄生虫之一,影响着大约一半的陆生节肢动物。有趣的是,感染能使宿主对其他病原体产生抗性并调节寿命,所以这种细菌类似于一种内共生体。在这里,我们证明体细胞通常会降解这些细菌细胞的一个子集,并且在抗生素损伤后,自噬是选择性清除沃尔巴克氏体所必需的。与此一致的是,在衰老过程中,沃尔巴克氏体在自噬功能受损的动物体内过度繁殖,而与对照果蝇的情况不同,它的存在并未影响宿主寿命。因此,沃尔巴克氏体的自噬降解代表了一种新的抗菌机制,该机制控制着这种独特细菌的繁殖,这种细菌同时兼具寄生虫和内共生体的特性。