Comparative analysis of Arabidopsis ecotypes reveals a role for brassinosteroids in root hydrotropism (Plant Physiol.)

Plastic plant growth serves them well, as it ensures efficient exploration of the environment. A plant can direct the growth of its roots towards the water, but the mechanisms behind hydrotropism are still to be fully understood. Miao et al. performed a screen of 30 Arabidopsis accessions for altered root hydrotropic responses. The accessions were screened on agar plates where a low moisture gradient was simulated by adding glycerol and alginate. The transcriptional differences between accessions differing in hydrotropic growth highlighted the importance of proton efflux, calcium influx and hormone signaling. The authors discovered that brassinosteroid signaling is involved in modulating the hydrotropic response, as the bri1 mutants showed hypersensitive hydrotropism response. (Summary by Magdalena Julkowska) Plant Physiol.10.1104/pp.17.01563