Although some nucleotide binding, leucine-rich repeat immune receptor (NLR) proteins conferring resistance to specific viruses have been identified in dicot plants, NLR proteins involved in viral resistance have not been described in monocots. We have used map-based cloning to isolate the CC-NB-LRR (CNL) Barley stripe mosaic virus (BSMV) resistance gene barley stripe resistance 1 (BSR1) from Brachypodium distachyon Bd3-1 inbred line. Stable BSR1 transgenic Brachypodium line Bd21-3, barley (Golden Promise) and wheat (Kenong 199) plants developed resistance against BSMV ND18 strain. Allelic variation analyses indicated that BSR1 is present in several Brachypodium accessions collected from countries in the Middle East. Protein domain swaps revealed that the intact LRR domain and the C-terminus of BSR1 are required for resistance. BSR1 interacts with the BSMV ND18 TGB1 protein in planta and shows temperature-sensitive antiviral resistance. The R390 and T392 residues of TGB1ND (ND18 strain) and the G196 and K197 residues within the BSR1 P-loop motif are key amino acids required for immune activation. BSR1 is the first cloned virus resistance gene encoding a typical CNL protein in monocots, highlighting the utility of the Brachypodium model for isolation and analysis of agronomically important genes for crop improvement.
Bibliographical noteFunding Information:
We would like to thank Drs Jialin Yu, Chenggui Han and Xian‐Bing Wang at China Agricultural University for their helpful comments. This work was supported by the National Key Research and Development Program of China (2021YFA1300703 to ZL), the National Natural Science Foundation of China (32122070 and 31872637 to YZ).
© 2022 The Authors. New Phytologist © 2022 New Phytologist Foundation. This article has been contributed to by US Government employees and their work is in the public domain in the USA.
- Barley stripe mosaic virus (BSMV)
- gene-for-gene interaction
- triple gene block 1 (TGB1)
ASJC Scopus subject areas
- Plant Science