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Drought is one of the most critical environmental stresses limiting plant growth and crop productivity. The synthesis and signaling of abscisic acid (ABA), a key phytohormone in the drought stress response, is under photoperiodic control. GIGANTEA (GI), a key regulator of photoperiod-dependent flowering and the circadian rhythm, is also involved in the signaling pathways for various abiotic stresses. In this study, we isolated ENHANCED EM LEVEL (EEL)/basic Leu zipper 12, a transcription factor involved in ABA signal responses, as a GI interactor in Arabidopsis (Arabidopsis thaliana). The diurnal expression of 9-CIS-EPOXYCAROTENOID DIOXYGENASE 3 (NCED3), a rate-limiting ABA biosynthetic enzyme, was reduced in the eel, gi-1, and eel gi-1 mutants under normal growth conditions. Chromatin immunoprecipitation and electrophoretic mobility shift assays revealed that EEL and GI bind directly to the ABA-responsive element motif in the NCED3 promoter. Furthermore, the eel, gi-1, and eel gi-1 mutants were hypersensitive to drought stress due to uncontrolled water loss. The transcript of NCED3, endogenous ABA levels, and stomatal closure were all reduced in the eel, gi-1, and eel gi-1 mutants under drought stress. Our results suggest that the EEL-GI complex positively regulates diurnal ABA synthesis by affecting the expression of NCED3, and contributes to the drought tolerance of Arabidopsis.

Void growth in ductile materials is an important problem from the fundamental and technological viewpoint. Most of the models developed to quantify and understand the void growth process did not take into account two important factors: the anisotropic nature of plastic flow in single crystals and the size effects that appear when plastic flow is confined into very small regions.

Miscanthus is one of the promising bioenergy plants, consisting of 42% cellulose and 25% hemicellulose. To use Miscanthus for bioenergy production pretreatment method should be determined and optimized. In this study, the factors for dilute acid pretreatment of Miscanthus were optimized by response surface method (RSM). Optimization experiments were performed within the scope of 133~168 oC, 0.63~2.4% sulfuric acid, and 1.34 ~19 min of reaction time. The optimal conditions were determined as 152 oC, 1% sulfuric acid, and 12 min reaction time. The predicted xylose yield at the optimal conditions and experimental yield were 89% and 91%, respectively. Acid¬pretreated Miscanthus was more efficiently hydrolyzed with a commercial cellulase than untreated NREL/TP¬510¬42618. The hydrolysate analysis was 60 one. Conversion rate was approximately 70%., Proceedings of the 20th European Biomass Conference and Exhibition, 18-22 June 2012, Milan, Italy, pp. 1685-1688