Cell cycle control in Arabidopsis

Although the basic mechanism of cell cycle control is conserved among eukaryotes, its regulation differs in each type of organism. Plants have unique developmental Features that distinguish them from other eukaryotes. These include the absence of cell migration, the formation of organs throughout the entire life-span from specialized regions called meristems, and the potency of non-dividing cells to re-enter the cell cycle. The study of plant cell cycle control genes is expected to contribute to the understanding of these unique developmental phenomena. The principal regulators of the eukaryotic cell cycle, the cyclin-dependent kinases (CDKs) and cyclins, are conserved in plants. This review focuses on cell cycle regulation in the plant Arabidopsis thaliana. While expression of one Arabidopsis CDK gene, Cdc2aAt, was positively correlated with the competence of cells to divide, expression of a mitotic-like cyclin, cyclAt, was almost exclusively confined to dividing cells. The expression of the Arabidopsis delta-type cyclins appears to be an early stage in the response of plant cells to external and internal stimuli. (C) 1996 Annals of Botany Company.