On Jun 11-th, 2018, Dr. Sheng Ye Laboratory published a research article on eLIFE entitled “Lateral interactions between protofilaments of the bacterial tubulin homolog FtsZ are essential for cell division”. The atomic details of lateral interactions between FtsZ protofilaments were revealed and their essential roles for cell division were confirmed.
The most common bacterial constriction system is based on the FtsZ protein,a prokaryotic cytoskeletal protein, whose protofilaments will form an essential ring structure during cell division. This structure, called as Z-ring, decreases in diameter and pulls the membrane inwards and causes the cell to constrict. The importance of the Z-ring has long been recognized, however, the precise nature of interactions between FtsZ protofilaments that organize the Z-ring and their physiological significance remain enigmatic. Dr. Ye’s group solved two crystallographic structures of a pair of FtsZ protofilaments, and demonstrated they assemble in an antiparallel manner through the formation of two different inter-protofilament lateral interfaces. Then, in vivo photo-crosslinking studies confirmed that such lateral interactions occur in living cells. The functional studies revealed that disruption of either interface will result in cell aberrant growth and death. Furthermore, all these results suggested that the interactions are weak on a per-subunit basis. So that the additive effect of such interactions along polymerized protofilaments are vital for them to incorporate into the Z-ring. And the inherently weak lateral interactions enable FtsZ protofilaments to self-organize into a dynamicring structure to guide the progressive insertion of new cell wall. These results have fundamental implications for understanding of how the Z-ring is organized and functions. In the long run, this knowledge might enable the design of new classes of antibiotics targeting the cell division process.
Graduate students Fenghui Guan, Jiayu Yu, Jie Yu, Ying Li and postdoc Yang Liu are the co-first authors of this study. Dr. Sheng Ye and Dr. Zengyi Chang from Peking University are the corresponding authors.
Link：https://elifesciences.org/articles/35578
