FtsZ in chloroplast division: structure, function and evolution.

FtsZ is a key cytoskeletal component of the chloroplast division machinery that arose from the related cell division FtsZ in the cyanobacterial ancestor of chloroplasts. FtsZ is widely conserved in photosynthetic eukaryotes, where it forms a ring inside the organelle at the chloroplast division site. A distinctive feature of chloroplast division systems is the evolution of two phylogenetically and structurally distinct FtsZ families by independent gene duplications in different photosynthetic lineages. While many functional aspects of these proteins remain unknown, recent studies on the biochemical and dynamic properties of FtsZs from land plants, in combination with ongoing research on bacterial FtsZs, have begun to suggest mechanisms by which two functionally distinct FtsZ proteins may cooperate to drive chloroplast division.