An Emerging Picture of Plastid Division in Higher Plants

Plastids are derived from endosymbiotic photosynthetic bacteria, so the division of plastids is controlled by a combination of prokaryote- and host eukaryote-derived proteins. Because of their prokaryotic origin, bacterial cell division has been successfully used as a paradigm for plastid division. This paradigm has resulted in the identification of the key plastid division components FtsZ, MinD, and MinE. However, most bacterial division factors are absent from chloroplasts, and the eukaryotic host has added several new components. Current research explores how these plastid division-related proteins interact with each other. FtsZ initiates plastid division, whereas the coordinated action of MinD and MinE ensures correct FtsZ (Z)-ring placement. Although the classical FtsZ antagonist MinC does not exist in plants , ARC3 can fulfill this role in Arabidopsis. Together with eukaryotic-derived proteins such as ARC5, ARTEMIS, PD rings and FZL and other prokaryotic-derived proteins such as ARC6 and GC1, these proteins make up a sophisticated division machinery in higher plants.