Fig. 6. A model for KIN10-promoted stomatal development through phosphorylation and stabilization of SPCH.

When plants were grown under conditions that are likely associated with mild energy starvation of plants, such as short photoperiod or liquid cultures, sucrose supply induced the KIN10 protein accumulation by increasing its translation. KIN10 displayed the cell-type-specific subcellular location pattern in the epidermal cells of leaves. The nuclear-localized KIN10 in stomatal-lineage cells phosphorylated and stabilized SPCH to promote stomatal development. Thus, the combination of multiple regulatory mechanisms controls the activity of KIN10 and thereby optimizes stomatal development.