文档介绍：Regulation of Plant Disease Resistance, Stress Responses,
Cell Death, and Ethylene Signaling in Arabidopsis
by the EDR1 Protein Kinase1
Dingzhong Tang, Katy M. Christiansen, and Roger W. Innes*
Department of Biology, Indiana University, Bloomington, Indiana 47405–7107
ENHANCED DISEASE RESISTANCE 1 (EDR1) encodes a CTR1-like kinase and was previously reported to function as
a negative regulator of disease resistance and ethylene-induced senescence. Here, we report that the edr1 mutant displays
enhanced stress responses and spontaneous necrotic lesions under drought conditions in the absence of pathogen, suggesting
that EDR1 is also involved in stress response signaling and cell death regulation. Double mutant analysis revealed that these
drought-induced phenotypes require salicylic acid but not ethylene signaling pathways. In addition, the edr1-mediated
ethylene-induced senescence phenotype was suppressed by mutations in EIN2, but not by mutations in SID2, PAD4, EDS1,or
NPR1, suggesting that EDR1 functions at a point of cross talk between ethylene and salicylic acid signaling that impinges on
senescence and cell death. Two edr1-associated phenotypes, drought-induced growth inhibition and ethylene-induced
senescence, were suppressed by mutations in ORE9, implicating ubiquitin-mediated protein degradation in the regulation
of these phenotypes. However, the ore9 mutat