STRIGOLACTONES: NEW PLAYERS IN THE NITROGEN-PHOSPHORUS SIGNALING INTERPLAY

MARRO, NICOLÁS; LIDOY, JAVIER; CHICO, MARÍA ÁNGELES; RIAL, CARLOS; MACÍAS, FRANCISCO A.; POZO, MARÍA J.; JANOUKOVÁ, MARTINA; LÓPEZ-RÁEZ, JUAN ANTONIO

Sevilla

Congreso; XVI MEETING OF PLANT MOLECULAR BIOLOGY; 2022

Instituto de Bioquímica Vegetal y Fotosíntesis (IBVF), CSIC-University of Sevilla

Nitrogen (N) and phosphorus (P) are among the most important macronutrients for plant growthand development, and the most widely used as fertilizers. Understanding how plants sense andrespond to N and P defciency is essential to optimize and reduce the use of chemical fertilizers.Strigolactones (SLs) are phytohormones acting as modulators and sensors of plant responses toP defciency. In the present work, we assess the potential role of SLs in N starvation and in theN-P signaling interplay. Physiological, transcriptional and metabolic responses were analyzed inwild-type and SL-defcient tomato plants grown under diferent P and N regimes, and in plantstreated with a short-term pulse of the synthetic SL analogue 2’-epi-GR24. The results evidencethat plants prioritize N over P status by afecting SL biosynthesis. We also show that SLs modulatethe expression of key regulatory genes of phosphate and nitrate signaling pathways, includingthe N-P integrators PHO2 and NIGT1/HHO. The results support a key role for SLs as sensorsduring early plant responses to both N and phosphate starvation and mediating the N-P signalinginterplay, indicating that SLs are involved in more physiological processes than so far proposed.