TY  - JOUR
AU  - Dai, Yongdong
AU  - Jiang, Yudong
AU  - Guo, Xiaoxuan
AU  - Zheng, Yumeng
AU  - Wang, Xiaowen
AU  - Tian, Weijiang
AU  - Li, Yangyang
AU  - Zeng, Zhengming
AU  - He, Guanghua
AU  - Sang, Xianchun
PY  - 2026
TI  - Dwarf and Brittle Culm 3, encoding a glycosyltransferase, is required for mechanical strength in rice
JO  - The Crop Journal
SN  - 2095-5421
SP  - 325
EP  - 335
VL  - 14
IS  - 2
AB  - 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.
UR  - https://doi.org/10.1016/j.cj.2025.11.004
DO  - 10.1016/j.cj.2025.11.004