摘要
The shoot apical meristem(SAM)is responsible for overall shoot growth by generating all aboveground structures.Recent research has revealed that the SAM displays an autonomous heat stress(HS)memory of a previous non-lethal HS event.Considering the importance of the SAM for plant growth,it is essential to determine how its thermomemory is mechanistically controlled.Here,we report that HEAT SHOCK TRAN-SCRIPTION FACTOR A7b(HSFA7b)plays a crucial role in this process in Arabidopsis,as the absence of functional HSFA7b results in the temporal suppression of SAM activity after thermopriming.We found that HSFA7b directly regulates ethylene response at the SAM by binding to the promoter of the key ethylene signaling gene ETHYLENE-INSENSITIVE 3 to establish thermotolerance.Moreover,we demonstrated that HSFA7b regulates the expression of ETHYLENE OVERPRODUCER 1(ETO1)and ETO1-LIKE 1,both of which encode ethylene biosynthesis repressors,thereby ensuring ethylene homeostasis at the SAM.Taken together,these results reveal a crucial and tissue-specic role for HSFA7b in thermomemory at the Arabidopsis SAM.
基金
funding Collaborative Research Centre 973"Priming and Memory of Organismic Responses to Stress" (www.sfb973.de)
the European Union’s Horizon 2020 Research and Innovation Programme for funding project PlantaSYST (SGA-CSA No.739582 under FPA No.664620)
the European Regional Development Fund for funding project BG05M2OP001-1.003-001-C01 through the Bulgarian"Science and Education for Smart Growth"Operational Programme,and the MPI-MP and the University of Potsdam for financial support.B.M.-R.and S.J.thank the International Max Planck Research School"Primary Metabolism and Plant Growth" (IMPRS-PMPG)for support.J.J.O.thanks the DFG (OL 767/1-1)
Leibniz Institute of Vegetable and Ornamental Crops for funding.
