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Brassinosteroids (BRs) are a class of plant hormones having great potential in improvement of plant performance under either normal or adverse conditions.However, the molecular mechanisms underlying their diverse functions were not fully understood, especially in crop plant.In rice, BRs have significant functions in regulating plant height, lamina inclination and grain size by mainly promoting cell elongation.We have identified a GRAS family protein named DLT, and demonstrated that DLT acts as a direct downstream target of GSK2, a GSK3/SHAGGY-like kinase, to mediate BR regulation of plant architecture in rice.By extensively analyses of a number of BR-related mutants, we further revealed that physiological BR stimulates cell elongation by promoting gibberellin (GA) biosynthesis,whereas exogenous high BR would lead to GA inactivation resulting in inhibition of cell elongation and plant growth.Moreover, we identified a quantitative trait locus named GL2 which controls grain length by activation of BR responses.Here, we presented our latest progress regarding how BR regulates stress response, focusing on the salt stress.We showed that DLT plays a crucial role in plant tolerance to salt stress and identified a DLT-interacting protein (DIP1) involved in this process.We demonstrated that DIP1 antagonizes DLT to modulate expression of a number of genes to regulate BR and salt stress responses.Our results suggested a novel role of DIP1 in regulating gene expression and revealed the molecular mechanism underlying the BR regulation of salt stress response.