细胞分裂是生物体内非常重要的生命活动。近年来的研究发现,硫化叶菌Sulfolobus等古菌中存在三种蛋白CdvA、CdvB和CdvC，参与细胞分裂。其中CdvA为古菌所特有,细胞分裂过程中可能与膜结合, 而CdvB和CdvC则分别为真核生物膜泡转运蛋白复合体III (ESCRT-III)及膜泡蛋白分选蛋白4(Vps4)的同源蛋白,可能在硫化叶菌等古菌中参与细胞分裂、囊泡分离和病毒出芽等过程中膜的切割。真核生物中共有四种ESCRT-III蛋白,它们之间及其与Vps4之间的相互关系仍不十分清楚。有趣的是，硫化叶菌中包括CdvB也有四种ESCRT-III同源蛋白,其功能和作用机制也不明了。本项目将利用遗传学、细胞生物学和生化方法,研究冰岛硫化叶菌CdvB外其它三种ESCRT-III同源蛋白的体内功能,分析它们在细胞分裂中的具体作用,进一步阐明硫化叶菌细胞分裂机制，并为真核生物相关研究提供借鉴。

Cell division is one of the most fundamental processes of life. Recent studies have shown that Sufolobus and other archae have three proteins, CdvA、CdvB and CdvC (cell division protein A,B and C) which are involved in cell division of these archaea. Among them, CdvA is an archaea-specific protein which is able to bind membrane. CdvB and CdvC are the homologues of the eukaryotic ESCRT-III (endosomal sorting complex III required for transport）and vacuolar protein sorting 4 (Vps4), respectively, which are putatively involved in membrane insicion duiring cell division, vacuolar formation, and virus budding in Sulfolobus and other archaea. Eukaryotes have four ESCRT-III proteins and the relationships between them and Vps4 have not been fully elucidated. Intriguingly, Sulfolobus has other three ESCR-TIII homologues besides CdvB, and the roles and mechanisms of them in cell division are obscure. In this project, we will investigate the in vivo roles of the three ESCRT-III protein homologues in S. islandicus by genetic, cell biological and biochmical approaches and dissect their specific roles and mechnisms in archaeal cell division. It is expected that the study would reveal the mechanism of archaea cell division and help for futher understanding of the cell division mechanism in eukaryotes.