A suberized exodermis is required for tomato drought tolerance

• Published in: Nature plants Vol. 10; no. 1; pp. 118 - 130
• Main Authors: Cantó-Pastor, Alex, Kajala, Kaisa, Shaar-Moshe, Lidor, Manzano, Concepción, Timilsena, Prakash, De Bellis, Damien, Gray, Sharon, Holbein, Julia, Yang, He, Mohammad, Sana, Nirmal, Niba, Suresh, Kiran, Ursache, Robertas, Mason, G. Alex, Gouran, Mona, West, Donnelly A., Borowsky, Alexander T., Shackel, Kenneth A., Sinha, Neelima, Bailey-Serres, Julia, Geldner, Niko, Li, Song, Franke, Rochus Benni, Brady, Siobhan M.
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 01-01-2024; Nature Publishing Group
• Subjects: 14/19; 14/28; 38/39; 38/91; 631/208/212/2019; 631/449/2653/1974; 631/449/2661/2146; 631/449/448/1365; Alcohol; BASIC BIOLOGICAL SCIENCES; Biomedical and Life Sciences; Biosynthesis; Cell wall; Diffusion barriers; Drought; Drought resistance; Enzymes; Fatty acids; Genes; Genetic analysis; Glycerol; Hypotheses; Life Sciences; Microscopy; Plant biology; Plant roots; Plant Sciences; Root apical meristem; Roots; Solutes; Tomatoes; Transcription factors; Transcriptomics; Water shortages
• ISSN: 2055-0278; 2055-0278
• DOI: 10.1038/s41477-023-01567-x

Plant roots integrate environmental signals with development using exquisite spatiotemporal control. This is apparent in the deposition of suberin, an apoplastic diffusion barrier, which regulates flow of water, solutes and gases, and is environmentally plastic. Suberin is considered a hallmark of endodermal differentiation but is absent in the tomato endodermis. Instead, suberin is present in the exodermis, a cell type that is absent in the model organism
Arabidopsis thaliana
. Here we demonstrate that the suberin regulatory network has the same parts driving suberin production in the tomato exodermis and the
Arabidopsis
endodermis. Despite this co-option of network components, the network has undergone rewiring to drive distinct spatial expression and with distinct contributions of specific genes. Functional genetic analyses of the tomato MYB92 transcription factor and ASFT enzyme demonstrate the importance of exodermal suberin for a plant water-deficit response and that the exodermal barrier serves an equivalent function to that of the endodermis and can act in its place.
Plant roots can respond to the environment by modifying cell type development. Here, the molecular pathways controlling root exodermal suberin are defined, as is its role in drought response. Modulating exodermal suberin levels can be a target for improved plant environmental resilience.