New insights into the bsr-d1-mediated broad-spectrum resistance to rice blast

Ziwei Zhu#, Junjie Yin#, Mawsheng Chern#, Xiaobo Zhu#, Chao Yang, Kaiwei He, Yuchen Liu, Min He, Jing Wang, Li Song, Long Wang, Yingjie Wei, Jichun Wang, Jiali Liu, Hai Qing, Yu Bi, Mingwu Li, Kun Hu, Tuo Qi, Qingqing Hou, Xuewei Chen, Weitao Li*

Molecular Plant Pathology（IF=4.326,TOP）,  2020  ,  21：951-860

https://bsppjournals.onlinelibrary.wiley.com/doi/full/10.1111/mpp.12941

Abstract

bsr‐d1, an allele encoding a transcription factor identified from the rice cultivar Digu, confers durable, broad‐spectrum resistance to infections by strains of Magnaporthe oryzae. bsr‐d1 was predicted to inhibit M. oryzae‐induced expression of Bsr‐d1 RNA and degradation of hydrogen peroxide to achieve resistance to M. oryzae. However, the global effect of biological process and molecular function on blast resistance mediated by Bsr‐d1 remains unknown. In this study, we compared transcriptomic profiling between Bsr‐d1 knockout (Bsr‐d1KO) lines and the wild type, TP309. Our study revealed that bsr‐d1 mainly regulates the redox state of plant cells, but also affects amino acid and unsaturated fatty acid metabolism. We further found that BSR‐D1 indirectly regulates salicylic acid biosynthesis, metabolism, and signal transduction downstream of the activation of H₂O₂ signalling in the bsr‐d1‐mediated immune response. Furthermore, we identified a novel peroxidase‐encoding gene, Perox3, as a new BSR‐D1 target gene that reduces resistance to M. oryzae when overexpressed in TP309. These results provide new insights into the bsr‐d1‐mediated blast resistance.