Root growth and branching are enabled by brassinosteroid-regulated growth anisotropy and carbon allocation.

ABSTRACT: Plants function as an integrated system of interconnected organs, with shoots and roots mutually influencing each other. Brassinosteroid (BR) signaling is essential for whole-plant growth, yet the relative importance of shoot versus root BR function in shaping root system architecture (RSA) remains unclear. Here, we directly tackle this question using micro-grafts between wild-type and BR-null mutants in both Arabidopsis and tomato, assisted by phenotyping, transcriptomics, metabolic profiling, transmission electron microscopy, and modeling approaches. These analyses demonstrate that shoot BR, by determining root carbon availability, allows for a full rescue of mutant root biomass, while loss of shoot BR attenuates root growth. In parallel, root BR dictates the spatial distribution of carb

SUBMITTER: Khandal H 

PROVIDER: S-EPMC12037908 | biostudies-literature | 2025 Apr

REPOSITORIES: biostudies-literature