An autoactive NB-LRR gene causes Rht13 dwarfism in wheat.
Philippa BorrillRohit MagoTianyuan XuBrett FordSimon J WilliamsAdinda DerkxWilliam D BovillJessica HylesDhara BhattXiaodi XiaColleen MacMillanRosemary G WhiteWolfram BussIstván MolnárSean WalkowiakOdd-Arne OlsenJaroslav DolezelCurtis J PozniakWolfgang SpielmeyerPublished in: Proceedings of the National Academy of Sciences of the United States of America (2022)
Semidwarfing genes have greatly increased wheat yields globally, yet the widely used gibberellin (GA)-insensitive genes Rht-B1b and Rht-D1b have disadvantages for seedling emergence. Use of the GA-sensitive semidwarfing gene Rht13 avoids this pleiotropic effect. Here, we show that Rht13 encodes a nucleotide-binding site/leucine-rich repeat ( NB-LRR ) gene. A point mutation in the semidwarf Rht-B13b allele autoactivates the NB-LRR gene and causes a height reduction comparable with Rht-B1b and Rht-D1b in diverse genetic backgrounds. The autoactive Rht-B13b allele leads to transcriptional up-regulation of pathogenesis-related genes including class III peroxidases associated with cell wall remodeling. Rht13 represents a new class of reduced height ( Rht ) gene, unlike other Rht genes, which encode components of the GA signaling or metabolic pathways. This discovery opens avenues to use autoactive NB-LRR genes as semidwarfing genes in a range of crop species, and to apply Rht13 in wheat breeding programs using a perfect genetic marker.