首页 | 本学科首页   官方微博 | 高级检索  
     


Ubiquitin-protein conjugates accumulate in the lysosomal system of fibroblasts treated with cysteine proteinase inhibitors.
Authors:F J Doherty   N U Osborn   J A Wassell   P E Heggie   L Laszlo     R J Mayer
Affiliation:Department of Biochemistry, University of Nottingham Medical School, Queen's Medical Centre, U.K.
Abstract:Mouse fibroblasts (3T3-L1 cells) accumulate detergent- and salt-insoluble aggregates of proteins conjugated to ubiquitin when incubated in the presence of inhibitors of lysosomal cysteine cathepsins, including E-64. These ubiquitin-protein conjugates co-fractionate with lysosomes on density gradients and are found in multivesicular dense bodies which by electron microscopy appear to be engaged in microautophagy. Both E-64 and ammonium chloride increase the intracellular concentration of free ubiquitin, but only E-64 leads to the formation of insoluble lysosomal ubiquitin-protein conjugates. The results are discussed in relation to the possible intracellular roles of ubiquitin conjugation.
Keywords:
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号