Mineral nutrients affect RALF-pectin condensation and signaling in roots
Paulina Ramirez Miranda (Germany)1 2; Ann-Kathrin Rößling (Germany)1 2; Miriam Kaltwasser (Germany)1; Friederike Göttmann (Germany)1; Jürgen Kleine-Vehn (Germany)1 2; Elke Barbez (Germany)1 2;
1 - Institute of Biology II, Molecular Plant Physiology (MoPP), University of Freiburg, 79104 Freiburg, Germany; 2 - Centre for Integrative Biological Signalling Studies (CIBSS), University of Freiburg, 79104 Freiburg, Germany;
Keywords: mineral nutrients; signaling kinases; pectin;
Abstract Topics: Theme 9: Cell Wall Function and Signaling in plant adaptation to Biotic and Abiotic Stresses
Type of Presentation: Oral Communication

Abstract text: The plant cell wall is characterized by a negative charge which is mainly attributed to pectin, an acidic polysaccharide. Newly synthesized pectin is highly methylated and therefore non-charged. Upon arrival to the cell wall, pectin is processed by enzymes from the PECTIN METHYL ESTERASE (PME), which de-methyl-esterify the pectin making it negatively charged. This results in a tremendous cation binding capacity of the cell walls (Haynes, 1980).

Recent studies demonstrate that cell wall charge is required for RALF-pectin phase separation and subsequent RALF-FERONIA signaling events, which regulate a wide range of cellular processes (Rössling et al., 2024 Elife; Liu et al., 2024).

Our unpublished work reveals that cationic mineral nutrients interact with pectin in the cell wall (Liu et al., unpublished). Here, I present how the environmental availability of mineral nutrients influences RALF-pectin condensate formation and the subsequent RALF/FERONIA signaling outputs.


References:
Haynes RJ. 1980. The Botanical Review 46: 75-99
Rößling A. et al. 2024. eLife 13:RP96943
Liu MJ. et al. 2023. Cell 187(2):312-330.e22.
Liu et al., unpublished