Nitrate modulates stem cell dynamics in Arabidopsis meristems through cytokinins ($) (PNAS)

The SAM (Shoot Apical Meristem) generates the cells that make up the shoot. In this paper, Landrein et al. studied how nutrient availability shapes SAM architecture. They showed that SAM size is positively correlated with both pTCSn::GFP (a cytokinin reporter) and pWUS::GFP (a major regulator for stem cell homeostasis) at various soil conditions. Additionally, they found that SAM size correlates with nitrate availability; nitrate modulates SAM homeostasis through IPTs (ISOPENTENYL TRANSFERASE) by modulating the expression of WUSCHEL. This mechanistic explanation from this study can be applied to crop plants to increase food production. (Summary by Arif Ashraf) PNAS: 10.1073/pnas.1718670115