Global warming profoundly affects plant communities,but the mechanisms and the identity of sensors con-trolling plant thermosensing remain poorly understood.In this study,we identify the heat-shock factor A1b(HsFA1b)t...Global warming profoundly affects plant communities,but the mechanisms and the identity of sensors con-trolling plant thermosensing remain poorly understood.In this study,we identify the heat-shock factor A1b(HsFA1b)transcription factoras a heat sensor that regulates stomatal responses by inhibiting open sto-mata 1(OsT1)kinase activity in Arabidopsis.OsT1 induces stomatal closure under heat stress indepen-dently of abscisic acid,and its activity is inhibited in the cytosol by the C-terminus of HSFA1b through intrinsic adenylate cyclase(AC)activity.Arabidopsis HSFA1b could complement an AC-deficient bacte-rium,andthe cyclic AMP produced by HSFA1b could bind to and inhibit OST1kinase activity.This inhibition is relieved under heat stress by HSFA1b translocation into the nucleus,coupling OST1 inhibition with the activation of heat-shock protein genes involved in the perception and signaling of high temperature.Collectively,our study demonstrates that HsFA1b functions as a heat sensor,inhibiting heat stress-induced andOsT1-mediated stomatalclosurethrough itsAC activity.展开更多
基金supported by the National Natural Science Foundation of China(U21A20206 and 32322010)the Education Department of Hainan Province(Hnjg2025ZD-90)the Natural Science Foundation of Henan Province(252300421075).
文摘Global warming profoundly affects plant communities,but the mechanisms and the identity of sensors con-trolling plant thermosensing remain poorly understood.In this study,we identify the heat-shock factor A1b(HsFA1b)transcription factoras a heat sensor that regulates stomatal responses by inhibiting open sto-mata 1(OsT1)kinase activity in Arabidopsis.OsT1 induces stomatal closure under heat stress indepen-dently of abscisic acid,and its activity is inhibited in the cytosol by the C-terminus of HSFA1b through intrinsic adenylate cyclase(AC)activity.Arabidopsis HSFA1b could complement an AC-deficient bacte-rium,andthe cyclic AMP produced by HSFA1b could bind to and inhibit OST1kinase activity.This inhibition is relieved under heat stress by HSFA1b translocation into the nucleus,coupling OST1 inhibition with the activation of heat-shock protein genes involved in the perception and signaling of high temperature.Collectively,our study demonstrates that HsFA1b functions as a heat sensor,inhibiting heat stress-induced andOsT1-mediated stomatalclosurethrough itsAC activity.
