Anti-ELF3 (aa 292-312) polyclonal antibody

Based on diel and circadian leaf transcriptomes in barley wild-type and clock mutant lines we predicted a structure of the barley circadian oscillator and interactions of its individual components with day/night cues. The circadian clock is a complex transcriptional network that regulates gene expression in anticipation of the day/night cycle and controls agronomic traits in plants. However, in crops, how the internal clock and day/night cues affect the transcriptome remains poorly understood. We analyzed thedieland circadian leaf transcriptomes in the barley (Hordeum vulgare) cultivar 'Bowman' and derived introgression lines harboring mutations inEARLY FLOWERING3(ELF3),LUX ARRHYTHMO1(LUX1), andEARLY MATURITY7(EAM7). Theelf3andlux1mutants exhibited abolished circadian transcriptome oscillations under constant conditions, whereaseam7maintained oscillations of approximate to 30% of the circadian transcriptome. However, day/night cues fully restored transcript oscillations in all three mutants and thus compensated for a disrupted oscillator in the arrhythmic barley clock mutantself3andlux1. Nevertheless,elf3, but notlux1, affected the phase of thedieloscillating transcriptome and thus the integration of external cues into the clock. Using dynamical modeling, we predicted a structure of the barley circadian oscillator and interactions of its individual components with day/night cues. Our findings provide a valuable resource for exploring the function and output targets of the circadian clock and for further investigations into thedieland circadian control of the barley transcriptome.

Arabidopsis adapts to elevated temperature by promoting stem elongation and hyponastic growth through a temperature-responsive transcription factor PIF4. Here we show that the evening-expressed clock component TOC1 interacts with and inactivates PIF4, thereby suppressing thermoresponsive growth in the evening. We find that the expression of PIF4 target genes show circadian rhythms of thermosensitivity, with minimum responsiveness in the evening when TOC1 level is high. Loss of function of TOC1 and its close homologue PRR5 restores thermosensitivity in the evening, whereas TOC1 overexpression causes thermo insensitivity, demonstrating that TOC1 mediates the evening-specific inhibition of thermoresponses. We further show that PIF4 is required for thermoadaptation mediated by moderately elevated temperature. Our results demonstrate that the interaction between TOC1 and PIF4 mediates the circadian gating of thermoresponsive growth, which may serve to increase fitness by matching thermoresponsiveness with the day-night cycles of fluctuating temperature and light conditions.