The tomato leaf as a model system for organogenesis

Abstract

Compound tomato leaves are composed of multiple lea fl ets that are generated gradually during leaf development, and each resembles a simple leaf. The elaboration of a compound leaf form requires the maintenance of transient organogenic activity at the leaf margin. The developmental window of organogenic activity is de fi ned by the antagonistic activities of factors that promote maturation, such as TCP transcription factors, SFT and gibberellin, and factors that delay maturation, such as KNOX transcription factors and cytokinin. Lea fl et initiation sites are speci fi ed spatially and temporally by spaced and speci fi c activities of CUCs, auxin and ENTIRE, as well as additional factors. The partially indeterminate growth of the compound tomato leaf makes it a useful model to understand the balance between determinate and indeterminate growth, and the mechanisms of organogenesis, some of which are common to many developmental processes in plants. © Springer Science+Business Media New York 2013.