Samson Rachel Y, Obita Takayuki, Freund Stefan M, Williams Roger L, Bell Stephen D
Medical Research Council (MRC) Cancer Cell Unit, Hills Road, Cambridge CB2 0XZ, UK.
Science. 2008 Dec 12;322(5908):1710-3. doi: 10.1126/science.1165322. Epub 2008 Nov 13.
Archaea are prokaryotic organisms that lack endomembrane structures. However, a number of hyperthermophilic members of the Kingdom Crenarchaea, including members of the Sulfolobus genus, encode homologs of the eukaryotic endosomal sorting system components Vps4 and ESCRT-III (endosomal sorting complex required for transport-III). We found that Sulfolobus ESCRT-III and Vps4 homologs underwent regulation of their expression during the cell cycle. The proteins interacted and we established the structural basis of this interaction. Furthermore, these proteins specifically localized to the mid-cell during cell division. Overexpression of a catalytically inactive mutant Vps4 in Sulfolobus resulted in the accumulation of enlarged cells, indicative of failed cell division. Thus, the archaeal ESCRT system plays a key role in cell division.
古菌是缺乏内膜结构的原核生物。然而，泉古菌界的一些嗜热成员，包括硫化叶菌属的成员，编码真核细胞内体分选系统组分Vps4和ESCRT-III（运输所需的内体分选复合物III）的同源物。我们发现硫化叶菌的ESCRT-III和Vps4同源物在细胞周期中经历表达调控。这些蛋白质相互作用，我们确定了这种相互作用的结构基础。此外，这些蛋白质在细胞分裂期间特异性定位于细胞中部。在硫化叶菌中过表达催化失活的突变体Vps4导致细胞增大并积累，这表明细胞分裂失败。因此，古菌的ESCRT系统在细胞分裂中起关键作用。
