Authors: Li Fan, Katja Fröhlich, Eric Melzer, Rory N. Pruitt, Isabell Albert, Lisha Zhang, Anna Joe, Chenlei Hua, Yanyue Song, Markus Albert, Sang-Tae Kim, Detlef Weigel, Cyril Zipfel, Eunyoung Chae, Andrea A. Gust, Thorsten Nürnberger
Published: 2022-03-11
DOI: 10.1038/s41467-022-28887-4
Source: Full article
AbstractActivation of plant pattern-triggered immunity (PTI) relies on the recognition of microbe-derived structures, termed patterns, through plant-encoded surface-resident pattern recognition receptors (PRRs). We show that proteobacterial translation initiation factor 1 (IF1) triggers PTI inArabidopsis thalianaand related Brassicaceae species. Unlike for most other immunogenic patterns, IF1 elicitor activity cannot be assigned to a small peptide epitope, suggesting that tertiary fold features are required for IF1 receptor activation. We have deployed natural variation in IF1 sensitivity to identifyArabidopsisleucine-rich repeat (LRR) receptor-like protein 32 (RLP32) as IF1 receptor using a restriction site-associated DNA sequencing approach. RLP32 confers IF1 sensitivity torlp32mutants, IF1-insensitiveArabidopsisaccessions and IF1-insensitiveNicotiana benthamiana, binds IF1 specifically and forms complexes with LRR receptor kinases SOBIR1 and BAK1 to mediate signaling. Similar to other PRRs, RLP32 confers resistance toPseudomonas syringae, highlighting an unexpectedly complex array of bacterial pattern sensors within a single plant species.