Dulbecco Telethon Institute, Department of Biology, University of Rome Tor Vergata, 00133 Rome, Italy.
Traffic. 2010 Oct;11(10):1280-9. doi: 10.1111/j.1600-0854.2010.01103.x.
Autophagy is a lysosome-mediated degradation pathway used by eukaryotes to recycle cytosolic components in both basal and stress conditions. Several genes have been described as regulators of autophagy, many of them being evolutionarily conserved from yeast to mammals. The study of autophagy-defective model systems has made it possible to highlight the importance of correctly functioning autophagic machinery in the development of invertebrates as, for example, during the complex events of fly and worm metamorphosis. In vertebrates, on the other hand, autophagy defects can be lethal for the animal if the mutated gene is involved in the early stages of development, or can lead to severe phenotypes if the mutation affects later stages. However, in both lower and higher eukaryotes, autophagy seems to be crucial during embryogenesis by acting in tissue remodeling in parallel with apoptosis. An increase of autophagic cells is, in fact, observed in the embryonic stages characterized by massive cell elimination. Moreover, autophagic processes probably protect cells during metabolic stress and nutrient paucity that occur during tissue remodeling. In light of such evidence, it can be concluded that there is a close interplay between autophagy and the processes of cell death, proliferation and differentiation that determine the development of higher eukaryotes.
自噬是真核生物用于在基础和应激条件下回收细胞质成分的溶酶体介导的降解途径。已经描述了几种作为自噬调节剂的基因，其中许多基因在从酵母到哺乳动物的进化过程中是保守的。自噬缺陷模型系统的研究使得突出正确功能的自噬机制在无脊椎动物的发育中的重要性成为可能，例如，在蝇和蠕虫变态过程的复杂事件中。另一方面，在脊椎动物中，如果突变基因参与早期发育，自噬缺陷可能对动物是致命的，或者如果突变影响后期阶段，则可能导致严重的表型。然而，在较低和较高的真核生物中，自噬似乎在胚胎发生过程中通过与细胞凋亡平行作用于组织重塑而至关重要。事实上，在以大量细胞消除为特征的胚胎阶段，观察到自噬细胞的增加。此外，自噬过程可能在组织重塑期间发生的代谢应激和营养缺乏期间保护细胞。有鉴于此，可以得出结论，自噬与决定高等真核生物发育的细胞死亡、增殖和分化过程之间存在密切的相互作用。
