In this study, the authors show that leaf epidermal cells acquire pavement cell identity by expressing the cell cycle inhibitory gene SIAMESE-RELATED1 (SMR1). In the absence of SMR1, apparently mature pavement cells lose their cell identity, dedifferentiate, and give rise to stomatal lineage cells. Since fine-tuning the number of stomata and pavement cells in leaves is crucial for leaf physiology under environmental stresses such as drought, the authors propose SMR1 as an exciting target for engineering climate-resilient plants.
See also press release regarding this paper.