Sakai Yasuyoshi, Oku Masahide, van der Klei Ida J, Kiel Jan A K W
Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Kitashirakawa-Oiwake, Kyoto 606-8502, Japan.
Biochim Biophys Acta. 2006 Dec;1763(12):1767-75. doi: 10.1016/j.bbamcr.2006.08.023. Epub 2006 Aug 24.
The abundance of peroxisomes within a cell can rapidly decrease by selective autophagic degradation (also designated pexophagy). Studies in yeast species have shown that at least two modes of peroxisome degradation are employed, namely macropexophagy and micropexophagy. During macropexophagy, peroxisomes are individually sequestered by membranes, thus forming a pexophagosome. This structure fuses with the vacuolar membrane, resulting in exposure of the incorporated peroxisome to vacuolar hydrolases. During micropexophagy, a cluster of peroxisomes is enclosed by vacuolar membrane protrusions and/or segmented vacuoles as well as a newly formed membrane structure, the micropexophagy-specific membrane apparatus (MIPA), which mediates the enclosement of the vacuolar membrane. Subsequently, the engulfed peroxisome cluster is degraded. This review discusses the current state of knowledge of pexophagy with emphasis on studies on methylotrophic yeast species.
细胞内过氧化物酶体的数量可通过选择性自噬降解（也称为过氧化物酶体自噬）迅速减少。对酵母物种的研究表明，至少采用了两种过氧化物酶体降解模式，即大过氧化物酶体自噬和微过氧化物酶体自噬。在大过氧化物酶体自噬过程中，过氧化物酶体被膜单独隔离，从而形成过氧化物酶体自噬体。这种结构与液泡膜融合，导致被包裹的过氧化物酶体暴露于液泡水解酶中。在微过氧化物酶体自噬过程中，一群过氧化物酶体被液泡膜突起和/或分段液泡以及一种新形成的膜结构——微过氧化物酶体自噬特异性膜装置（MIPA）包围，MIPA介导液泡膜的包围。随后，被吞噬的过氧化物酶体簇被降解。本综述讨论了过氧化物酶体自噬的当前知识状态，重点是对甲基营养酵母物种的研究。
