A growth-based framework for leaf shape development and diversity (Cell)

The leaf shape is one of the features defining the diversity in the plant kingdom. However, it is still not understood how action of individual genes is linked to this morphological diversity. Kierzkowski et al. developed an imaging protocol to study the leaf primodium development to understand the cellular growth patterning in two related species showing contrasting leaf morphology – A.thaliana and C.hirsuta. By combining time-lapse imaging, modeling and molecular biology, Kierzkowki et al. identified that the complex leaf shape of C. hirsuta is a result of two processes. The slow and extended growth throughout the primodium and delayed differentiation is regulated by the KNOX gene SHOOTMERISTEMLESS, while local growth inhibition, which emphasizes the marginal serrations, is orchestrated by the REDUCED COMPLEXITY (RCO) gene, which is absent in the A. thaliana genome.   (Summary by Magdalena Julkowska) Cell 10.1016/j.cell.2019.05.011