Transfer of a eubacteria-type cell division site-determining factor CrMinD gene to the nucleus from the chloroplast genome in Chlamydomonas reinhardtii  

作　　者：LIU WeiZhong HU Yong ZHANG RunJie ZHOU WeiWei ZHU JiaYing LIU XiangLin HE YiKun 

机构地区：[1]College of Life Science, Capital Normal University, Beijing 100037, China [2]College of Life Science, Shanxi Normal University, Linfen 041004, China College of Life Science, Shanxi Normal University, Linfen 041004, China

出　　处：《Chinese Science Bulletin》2007年第18期2514-2521,共8页

基　　金：Supported by the National Natural Science Foundation of China (Grant Nos. 30500288 and 30470879) ;the Natural Science Foundation of Beijing (Grant No. 5032003)

摘　　要：MinD is a ubiquitous ATPase that plays a crucial role in selection of the division site in eubacteria, chloroplasts, and probably Archaea. In four green algae, Mesostigma viride, Nephroselmis olivacea, Chlorella vulgaris and Prototheca wickerhamii, MinD homologues are encoded in the plastid genome. However, in Arabidopsis, MinD is a nucleus-encoded, chloroplast-targeted protein involved in chloro- plast division, which suggests that MinD has been transferred to the nucleus in higher land plants. Yet the lateral gene transfer (LGT) of MinD from plastid to nucleus during plastid evolution remains poorly understood. Here, we identified a nucleus-encoded MinD homologue from unicellular green alga Chlamydomonas reinhardtii, a basal species in the green plant lineage. Overexpression of CrMinD in wild type E. coli inhibited cell division and resulted in the filamentous cell formation, clearly demon- strated the conservation of the MinD protein during the evolution of photosynthetic eukaryotes. The transient expression of CrMinD-egfp confirmed the role of CrMinD protein in the regulation of plastid division. Searching all the published plastid genomic sequences of land plants, no MinD homologues were found, which suggests that the transfer of MinD from plastid to nucleus might have occurred be- fore the evolution of land plants.MinD is a ubiquitous ATPase that plays a crucial role in selection of the division site in eubacteria, chloroplasts, and probably Archaea. In four green algae, MesosUgma viride, Nephroselmis olivacea, Chlorella vulgaris and Prototheca wickerhamii, MinD homologues are encoded in the plastid genome. However, in Arabidopsis, MinD is a nucleus-encoded, chloroplast-targeted protein involved in chloroplast division, which suggests that MinD has been transferred to the nucleus in higher land plants. Yet the lateral gene transfer （LGT） of MinD from plastid to nucleus during plastid evolution remains poorly understood. Here, we identified a nucleus-encoded MinD homologue from unicellular green alga Chlamydomonas reinhardtii, a basal species in the green plant lineage. Overexpression of CrMinD in wild type E. coil inhibited cell division and resulted in the filamentous cell formation, clearly demonstrated the conservation of the MinD protein during the evolution of photosynthetic eukaryotes. The transient expression of CrMinD-egfp confirmed the role of CrMinD protein in the regulation of plastid division. Searching all the published plastid genomic sequences of land plants, no MinD homologues were found, which suggests that the transfer of MinD from plastid to nucleus might have occurred before the evolution of land plants.

关 键 词：衣藻 叶绿体 CrMinD基因 基因转移 植物进化 

分 类 号：Q943.2[生物学—植物学]