Work

Dwarf and Brittle Culm 3, encoding a glycosyltransferase, is required for mechanical strength in rice

Year: 2025

Type: article

Abstract: Plant mechanical strength affects lodging resistance and stress tolerance, highlighting the importance of elucidating the regulatory mechanisms underlying cell wall development. In this study, we identified a novel dwarf and brittle culm mutant, dbc3 , which exhibited reduced culm mechanical strength due to a thinner secondary cell wall, irregular distribution of the sclerenchyma cells under the epidermal layer and vascular bundle cells, as well as a significant reduction in cellulose and lignin content. Map-based cloning revealed that DBC3 encodes a xylan arabinosyltransferase belonging to the GT61 family. GUS staining and qRT-PCR showed that DBC3 was expressed in all tested tissues. Yeast one-hybrid, dual-luciferase assays and EMSA demonstrated that OsMYB63 directly bound to the DBC3 promoter to activate its expression. In the osmyb63 knockout mutant, DBC3 expression was significantly reduced, accompanied by a moderate decrease in stem mechanical strength. Taken together, these findings suggest that DBC3 , as a direct target gene of OsMYB63, plays an important role in regulating plant mechanical strength by modulating cell wall development.

Source: The Crop Journal

DOI: 10.1016/j.cj.2025.11.004