Rojo Enrique, Zouhar Jan, Carter Clay, Kovaleva Valentina, Raikhel Natasha V
Department of Botany and Plant Sciences and Center for Plant Cell Biology, University of California, Riverside, CA 92521, USA.
Proc Natl Acad Sci U S A. 2003 Jun 10;100(12):7389-94. doi: 10.1073/pnas.1230987100. Epub 2003 May 28.
Precursor protease vesicles are plant-specific compartments containing precursors of enzymes that are thought to participate in the degradation of cellular components in organs undergoing senescence. We report in vivo evidence that the precursor protease vesicle-localized vacuolar processing enzyme-gamma (VPEgamma) is critical for maturation of the plant vacuolar protease AtCPY. We also provide biochemical and functional evidence that VPEgamma is involved in degradation of the vacuolar invertase AtFruct4 in aging tissues. Moreover, a proteomics-based approach identified various proteins found in the vacuoles of aging vpegamma mutants but not in WT plants, suggesting a unique role of VPEgamma in protein processing and degradation in Arabidopsis.
前体蛋白酶囊泡是植物特有的区室,含有被认为参与衰老器官中细胞成分降解的酶的前体。我们报告了体内证据,即定位于前体蛋白酶囊泡的液泡加工酶γ(VPEγ)对植物液泡蛋白酶AtCPY的成熟至关重要。我们还提供了生化和功能证据,表明VPEγ参与衰老组织中液泡转化酶AtFruct4的降解。此外,基于蛋白质组学的方法鉴定出了衰老的vpegamma突变体液泡中存在但野生型植物中不存在的各种蛋白质,这表明VPEγ在拟南芥的蛋白质加工和降解中具有独特作用。