Recognition of Microbe- or Host Damage-associated Pattern Triggers Salt Stress Tolerance in Arabidopsis thaliana

Eliza Loo ¹ Kohji Yamada ² Yuri Tajima ¹ Taishi Hirase ¹ Hirotaka Ariga ³ Tadashi Fujiwara ¹ Teruaki Taji ³ Yusuke Saijo ^1,4

¹Graduate School of Biological Science, Nara Institute of Science and Technology, Japan
²Department of Plant Microbe Interaction, Max Planck Institute for Plant Breeding Research, Germany
³Department of Bioscience, Tokyo University of Agriculture, Japan
⁴Japan Science and Technology Agency (JST), Precursory Research for Embryonic Science and Technology (PRESTO), Japan

Plants cope with biotic and abiotic factors in the environment via a process that remains elusive. Here, we report that recognition of microbe- and damage-associated molecular patterns (MAMPs/DAMPs) via pattern recognition receptors (PRRs) triggers salt stress tolerance in Arabidopsis thaliana, designated pattern-triggered salt tolerance (PTST). Seedlings pre-treated with the bacterial MAMPs flagellin (flg22) and EF-Tu (elf18) or the DAMPs Pep peptides exhibit enhanced salt tolerance. PEP Receptor1 (PEPR1) and PEPR2 overexpression also confers salt tolerance without exogenous MAMP/DAMP application. Transcriptome and genetic analyses point to a critical role for the transcription factors WRKY18/WRKY40 in PTST. Moreover, non-pathogenic bacteria also enhance salt tolerance through PRRs, pointing to the physiological relevance of PTST. Our findings indicate that PRRs facilitate plant adaptation to both biotic and abiotic stresses.