VanderVen Kyle, Butcher Conner, Fokine Remi', Li Jianhui
Biomedical Engineering and Science, Florida Institute of Technology, Melbourne, Florida, United States.
MicroPubl Biol. 2025 May 7;2025. doi: 10.17912/micropub.biology.001579. eCollection 2025.
Autophagic degradation of proteasomes is a highly conserved mechanism for regulating proteasome homeostasis in eukaryotes. Here we show that Pep12, a t-SNARE protein, is important for intralumenal vesicle formation in the vacuole and proteasome microautophagy under low glucose conditions. Deleting in yeast cells, , blocked proteasome fragmentation, by which the ESCRT-dependent microautophagy selectively degrades aberrant proteasomes. Accumulation of aberrant proteasomes interfered with proteasome condensate formation in cells. Autophagic bodies were present, but intralumenal vesicles and proteasome microautophagy were absent in the vacuole of cells. Therefore, Pep12 plays an important role in proteasome microautophagy.
蛋白酶体的自噬降解是真核生物中调节蛋白酶体稳态的一种高度保守的机制。在这里，我们表明Pep12，一种t-SNARE蛋白，在低葡萄糖条件下对于液泡内囊泡形成和蛋白酶体微自噬很重要。在酵母细胞中缺失Pep12会阻止蛋白酶体碎片化，通过这种方式，依赖于ESCRT的微自噬选择性地降解异常蛋白酶体。异常蛋白酶体的积累干扰了酵母细胞中蛋白酶体凝聚物的形成。自噬体存在，但酵母细胞液泡中不存在腔内囊泡和蛋白酶体微自噬。因此，Pep12在蛋白酶体微自噬中起重要作用。
