Nitrate-regulated growth processes involve activation of gibberellin pathway

Lucie Camut (1) , Barbora Gallova (2) , Lucas Jilli (1) , Mathilde Sirlin-Josserand (1) , Esther Carrera (3) , Lali Sakvarelidze-Achard (1) , Julie Zumsteg (1) , Dimitri Heintz (1) , Sandrine Ruffel (4) , Gabriel Krouk (4) , Stephen G Thomas (2) , Peter Hedden (2, 5) , Andrew L Phillips (2) , Jean-Michel Davière (1) , Patrick Achard (1)

1 IBMP - Institut de Biologie Moléculaire des Plantes
2 Rothamsted Research
3 IBMCP - Instituto de Biologia Molecular y Celular de Plantas
4 IPSIM - Institut des Sciences des Plantes de Montpellier
5 LGR - Laboratory of Growth Regulators [Univ Palacký]

Nitrate, one of the main nitrogen (N) sources for crops, acts as a nutrient and key signaling molecule coordinating gene expression, metabolism and various growth processes throughout the plant life cycle. It is widely accepted that nitrate-triggered developmental programs cooperate with hormone synthesis and transport, to finely adapt plant architecture to N availability. Here, we report that nitrate, acting through its signaling pathway, promotes growth in Arabidopsis and wheat, in part by modulating the accumulation of gibberellin (GA)-regulated DELLA growth repressors. We show that nitrate reduces the abundance of DELLAs by increasing GA contents through activation of GA metabolism gene expression. Consistently, the growth restraint conferred by nitrate deficiency is partially rescued in global-DELLA mutant that lacks all DELLAs. At the cellular level, we show that nitrate enhances both cell proliferation and elongation in a DELLA-dependent and-independent manner, respectively. Our findings establish a connection between nitrate and GA signaling pathways that allow plants to adapt their growth to nitrate availability.

Domaines: Biologie végétale; Sciences du Vivant [q-bio]

Lucie Camut, Barbora Gallova, Lucas Jilli, Mathilde Sirlin-Josserand, Esther Carrera, et al.. Nitrate-regulated growth processes involve activation of gibberellin pathway. 2022. ⟨hal-03858033⟩