AUTHOR=Jin Yuli , Liu Hong , Gu Tiantian , Xing Lixian , Han Guohao , Ma Pengtao , Li Xiuquan , Zhou Yilin , Fan Jieru , Li Lihui , An Diaoguo 

TITLE=PM2b, a CC-NBS-LRR protein, interacts with TaWRKY76-D to regulate powdery mildew resistance in common wheat

JOURNAL=Frontiers in Plant Science

VOLUME=Volume 13 - 2022

YEAR=2022

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2022.973065

DOI=10.3389/fpls.2022.973065

ISSN=1664-462X

ABSTRACT=Powdery mildew caused by Blumeria graminis f. sp. tritici (Bgt) is a destructive disease of wheat throughout the world. Utilization of host resistance is considered the most sustainable way to control this disease. Pm2b conferred resistance to powdery mildew in wheat line KM2939. In this study, Pm2b was delimited to a 1.64 Mb physical interval using a large segregating population containing 4354 F2:3 families of KM2939 and susceptible cultivar Shimai 15. In this interval, TraesCS5D03G0111700 encoding the coiled-coil nucleotide-binding site leucine-rich repeat protein (CC-NBS-LRR) was determined as the candidate gene of Pm2b. Silencing by barley stripe mosaic virus-induced gene silencing (BSMV-VIGS) technology and two independent mutants analysis in KM2939 confirmed the candidate gene TraesCS5D03G0111700 was Pm2b. Subcellular localization showed Pm2b was located on the cell nucleus, membrane and cytoplasm. Pm2b had the highest expression level in leaves and was rapidly up-regulated after inoculating Bgt isolate E09. The yeast two-hybrid (Y2H) and luciferase complementation imaging assays (LCI) showed that PM2b could self-associate through the NB domain. Notably, we identified PM2b interacting with the transcription factor TaWRKY76-D, which depended on the NB domain of PM2b and WRKY domain of TaWRKY76-D. TaWRKY76-D negatively regulated the resistance to powdery mildew confirmed by BSMV-VIGS analysis. The specific marker K529 could take the advantage of high-throughput and high-efficiency for detecting Pm2b and be useful in molecular marker assisted-selection breeding. In this study, we map-based cloned Pm2b and revealed its disease resistance mechanism, which provided theoretical basis for wheat disease resistance breeding.