Hydraulic flux–responsive hormone redistribution determines root branching

Mehra, Poonam; Pandey, Bipin K.; Melebari, Dalia; Banda, Jason; Leftley, Nicola; Couvreur, Valentin; Rowe, James; Anfang, Moran; De Gernier, Hugues; Morris, Emily; Sturrock, Craig J.; Mooney, Sacha J.; Swarup, Ranjan; Faulkner, Christine; Beeckman, Tom; Bhalerao, Rishikesh P.; Shani, Eilon; Jones, Alexander M.; Dodd, Ian C.; Sharp, Robert E.; Sadanandom, Ari; Draye, Xavier; Bennett, Malcolm J.

Abstract

Plant roots exhibit plasticity in their branching patterns to forage efficiently for heterogeneously distributed resources, such as soil water. The xerobranching response represses lateral root formation when roots lose contact with water. Here, we show that xerobranching is regulated by radial movement of the phloem-derived hormone abscisic acid, which disrupts intercellular communication between inner and outer cell layers through plasmodesmata. Closure of these intercellular pores disrupts the inward movement of the hormone signal auxin, blocking lateral root branching. Once root tips regain contact with moisture, the abscisic acid response rapidly attenuates. Our study reveals how roots adapt their branching pattern to heterogeneous soil water conditions by linking changes in hydraulic flux with dynamic hormone redistribution.

Citation

Mehra, P., Pandey, B. K., Melebari, D., Banda, J., Leftley, N., Couvreur, V., Rowe, J., Anfang, M., De Gernier, H., Morris, E., Sturrock, C. J., Mooney, S. J., Swarup, R., Faulkner, C., Beeckman, T., Bhalerao, R. P., Shani, E., Jones, A. M., Dodd, I. C., Sharp, R. E., …Bennett, M. J. (2022). Hydraulic flux–responsive hormone redistribution determines root branching. Science, 378(6621), 762-768. https://doi.org/10.1126/science.add3771

• Journal Article Type: Article
• Acceptance Date: Oct 24, 2022
• Online Publication Date: Nov 17, 2022
• Publication Date: Nov 18, 2022
• Deposit Date: Apr 3, 2024
• Journal: Science
• Print ISSN: 0036-8075
• Electronic ISSN: 1095-9203
• Publisher: American Association for the Advancement of Science
• Peer Reviewed: Peer Reviewed
• Volume: 378
• Issue: 6621
• Pages: 762-768
• DOI: https://doi.org/10.1126/science.add3771
• Public URL: https://nottingham-repository.worktribe.com/output/13754531
• Publisher URL: https://www.science.org/doi/10.1126/science.add3771