Plant D-type (CycD) cyclins and the regulation of the plant cell cycle

Progression through the eukaryotic cell cycle is driven by the sequential activation and destruction of kinase complexes, consisting of a serine/threonine cyclin-dependent kinase (cdk) bound to a regulatory cyclin. The cdk is dependent on binding the cyclin for activity, and the cyclin determines the substrate specificity and subcellular localisation of the complex. In animals multiple cdks and cyclins are involved in the control of cell cycle progression. Cyclins are classified as being mitotic (A or B-type) or G1 (D or E-type) cyclins based on sequence criteria and the region of the cell cycle they regulate.