Ostersetzer Oren, Kato Yusuke, Adam Zach, Sakamoto Wataru
Agricultural Research Organization, Volcani Center, Bet Dagan 50250, Israel.
Plant Cell Physiol. 2007 Jun;48(6):881-5. doi: 10.1093/pcp/pcm052. Epub 2007 May 3.
Arabidopsis contains four Lon protease-like proteins (AtLon1-AtLon4), predicted to be localized in different cellular organelles, including mitochondria, peroxisomes and plastids. A notable question is whether Lon is present in chloroplasts, since it is absent from cyanobacteria and thus appears to have been lost during the evolution of photosynthetic organisms. Based on in vivo transient assays, we found that AtLon4 is dually targeted to both mitochondria and chloroplasts. Furthermore, immunoblot analysis localized AtLon4 to the thylakoids. Thus, in spite of its absence from basal photosynthetic organisms, our results suggest the presence of Lon in plant plastids.
拟南芥含有四种Lon蛋白酶样蛋白（AtLon1 - AtLon4），预计定位于不同的细胞器，包括线粒体、过氧化物酶体和质体。一个值得注意的问题是Lon是否存在于叶绿体中，因为蓝细菌中没有Lon，因此在光合生物的进化过程中似乎已经丢失。基于体内瞬时分析，我们发现AtLon4双靶向定位于线粒体和叶绿体。此外，免疫印迹分析将AtLon4定位到类囊体。因此，尽管基础光合生物中不存在Lon，但我们的结果表明植物质体中存在Lon。
