TY - JOUR A1 - Brotman, Yariv A1 - Landau, Udi A1 - Pnini, Smadar A1 - Lisec, Jan A1 - Balazadeh, Salma A1 - Müller-Röber, Bernd A1 - Zilberstein, Aviah A1 - Willmitzer, Lothar A1 - Chet, Ilan A1 - Viterbo, Ada T1 - The LysM Receptor-Like Kinase LysM RLK1 is required to activate defense and abiotic-stress responses induced by overexpression of fungal chitinases in arabidopsis plants JF - Molecular plant N2 - Application of crab shell chitin or pentamer chitin oligosaccharide to Arabidopsis seedlings increased tolerance to salinity in wild-type but not in knockout mutants of the LysM Receptor-Like Kinase1 (CERK1/LysM RLK1) gene, known to play a critical role in signaling defense responses induced by exogenous chitin. Arabidopsis plants overexpressing the endochitinase chit36 and hexoaminidase excy1 genes from the fungus Trichoderma asperelleoides T203 showed increased tolerance to salinity, heavy-metal stresses, and Botrytis cinerea infection. Resistant lines, overexpressing fungal chitinases at different levels, were outcrossed to lysm rlk1 mutants. Independent homozygous hybrids lost resistance to biotic and abiotic stresses, despite enhanced chitinase activity. Expression analysis of 270 stress-related genes, including those induced by reactive oxygen species (ROS) and chitin, revealed constant up-regulation (at least twofold) of 10 genes in the chitinase-overexpressing line and an additional 76 salt-induced genes whose expression was not elevated in the lysm rlk1 knockout mutant or the hybrids harboring the mutation. These findings elucidate that chitin-induced signaling mediated by LysM RLK1 receptor is not limited to biotic stress response but also encompasses abiotic-stress signaling and can be conveyed by ectopic expression of chitinases in plants. KW - abiotic stress KW - chitin-induced signaling KW - chitinases KW - LysM receptor kinase KW - Trichoderma Y1 - 2012 U6 - https://doi.org/10.1093/mp/sss021 SN - 1674-2052 VL - 5 IS - 5 SP - 1113 EP - 1124 PB - Oxford Univ. Press CY - Oxford ER -