Diatom cell division in an environmental context

▶ Marine diatoms possess unique cell division features. ▶ Comparative and functional genomic analyses provide the first molecular information about diatom cell division mechanisms. ▶ The diatom cell cycle is finely tuned to inputs derived from both endogenous and environmental signals. Studies of cell division in organisms derived from secondary endosymbiosis such as diatoms have revealed that the mechanisms are far from those found in more conventional model eukaryotes. An atypical acentriolar microtuble-organizing centre, centripetal cytokinesis combined with centrifugal cell wall neosynthesis, and the role of sex in relation to cell size restoration make diatoms an exciting system to re-investigate the evolution, differentiation and regulation of cell division. Such studies are further justified considering the ecological relevance of these microalgae in contemporary oceans and the need to understand the mechanisms controlling their growth and distribution in an environmental context. Recent work derived from genome-wide analyses on representative model diatoms reveals that the cell cycle is finely tuned to inputs derived from both endogenous and environmental signals.