Abstract
The phytohormone jasmonate(JA)coordinates stress and growth responses to increase plant survival in unfavorable environments.Although JA can enhance plant UV-B stress tolerance,the mechanisms underlying the interaction of UV-B and JA in this response remain unknown.In this study,we demonstrate that the UV RESISTANCE LOCUS 8-TEOSINTE BRANCHED1,Cycloidea and PCF 4-LIPOXYGENASE2(UVR8-TCP4-LOX2)module regulates UV-B tolerance dependent on JA signaling pathway in Arabidopsis thaliana.We show that the nucleus-localized UVR8 physically interacts with TCP4 to increase the DNA-binding activity of TCP4 and upregulate the JA biosyn-thesis gene LOX2.Furthermore,UVR8 activates the expression of LOX2 in a TCP4-dependent manner.Our genetic analysis also provides evi-dence that TCP4 acts downstream of UVR8 and upstream of LOX2 to mediate plant responses to UV-B stress.Our results illustrate that the UV-B-dependent interaction of UVR8 and TCP4 serves as an important UVR8-TCP4-LOX2 module,which integrates UV-B radiation and JA signaling and represents a new UVR8 signaling mechanism in plants.
基金项目
Second Tibetan Plateau Scientific Expedition and Research(STEP)program(2019QZKK0502)
National Natural Science Foundation of China(32370405)