Poster
Leon Pierdzig
Department of Plant Cell Biology, Georg-August-University Göttingen
Göttingen, Niedersachsen, Germany
Christine Seinsche
University-Göttingen
Göttingen, Niedersachsen, Germany
Samantha Armiento
Università di Napoli Federico II
Napoli, Campania, Italy
Lisa Schulz
University Goettingen
Goettingen, Niedersachsen, Germany
Jeanine Rismondo
University Goettingen
Goettingen, Niedersachsen, Germany
Cristina De Castro
Università di Napoli Federico II
Napoli, Campania, Italy
Antonio Molinaro
Università di Napoli Federico II
Napoli, Campania, Italy
Elena Petutschnig
University Goettingen
Goettingen, Niedersachsen, Germany
Volker Lipka
Department of Plant Cell Biology, Georg-August-University Göttingen
Göttingen, Niedersachsen, Germany
Plants employ a diverse array of cell-surface receptors to detect microbe-associated molecular patterns (MAMPs), which have been extensively studied in gram-negative bacteria. However, our understanding of MAMPs from gram-positive bacteria remains limited. Wall teichoic acids (WTAs) are large, anionic glycopolymers unique to the cell wall of gram-positive bacteria. Here, we demonstrate that glycosylated WTAs from various gram-positive bacteria function as a gram-positive-specific MAMP, triggering salicylic acid signaling and a non-canonical programmed cell death response in Arabidopsis. Genetic evidence reveals that plant recognition of WTAs relies on Cysteine-rich Receptor-like Kinase 7 (CRK7). WTA pretreatment activates priming, alters defense gene expression and systemically boosts the plant's immune system leading to increased resistance against the gram-negative model pathogen Pseudomonas syringae. FLIM/FRET analysis further shows that in the presence of WTA, CRK7 dimerizes, suggesting that CRK7 is a bona fide receptor for WTA. In conclusion, we identified the first MAMP specific to gram-positive bacteria and thus the first carbohydrate ligand of plant cysteine-rich receptor-like kinases.