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Soybean ( Glycine max) is a globally important crop, and its growth and yield are severely reduced by abiotic stresses, such as drought, heat, and cold. The cis-acting element DRE (dehydration-responsive element)/ CRT plays an important role in activating gene expression in response to these stresses. The Arabidopsis DREB1/ CBF genes that encode DRE-binding proteins function as transcriptional activators in the cold stress responsive gene expression. In this study, we identified 14 DREB1-type transcription factors (Gm DREB1s) from a soybean genome database. The expression of most Gm DREB1 genes in soybean was strongly induced by a variety of abiotic stresses, such as cold, drought, high salt, and heat. The Gm DREB1 proteins activated transcription via DREs (dehydration-responsive element) in Arabidopsis and soybean protoplasts. Transcriptome analyses using transgenic Arabidopsis plants overexpressing Gm DREB1s indicated that many of the downstream genes are cold-inducible and overlap with those of Arabidopsis DREB1A. We then comprehensively analyzed the downstream genes of Gm DREB1B;1, which is closely related to DREB1A, using a transient expression system in soybean protoplasts. The expression of numerous genes induced by various abiotic stresses were increased by overexpressing Gm DREB1B;1 in soybean, and DREs were the most conserved element in the promoters of these genes. The downstream genes of Gm DREB1B;1 included numerous soybean-specific stress-inducible genes that encode an ABA receptor family protein, Gm PYL21, and translation-related genes, such as ribosomal proteins. We confirmed that Gm DREB1B;1 directly activates Gm PYL21 expression and enhances ABRE-mediated gene expression in an ABA-independent manner. These results suggest that Gm DREB1 proteins activate the expression of numerous soybean-specific stress-responsive genes under diverse abiotic stress conditions. [ABSTRACT FROM AUTHOR]

Pulsed cathodic arc-plasma deposition was employed to create a few nanometre-thick Pt overlayer on a 50 μm-thick Fe-Cr-Al metal (SUS) foil, resulting in an effective NH 3 oxidation catalyst fabrication. This catalyst exhibited a turnover frequency (TOF) exceeding 100 times that of Pt nanoparticles. In this study, Pt overlayer catalysts with varying degrees of surface roughness were fabricated using different metal foil substrates: mirror-polished (Pt/p-SUS), unpolished (Pt/SUS) and roughened by the formation of a surface oxide layer (Pt/Al 2 O 3 /SUS). The nanoscale roughness was comprehensively analysed using electron microscopy, laser scanning confocal microscopy and chemisorption techniques. NH 3 oxidation activity, measured at 200 °C, followed an increasing trend in the order of Pt/Al 2 O 3 /SUS < Pt/SUS < Pt/p-SUS, despite a decrease in the apparent Pt surface area in the same order. Consequently, the calculated TOF was markedly higher for Pt/p-SUS (267 min -1 ) compared to Pt/SUS (107 min -1 ) and Pt/Al 2 O 3 /SUS (≤22 min -1 ). The smooth Pt overlayer surface also favoured N 2 yield over N 2 O at this temperature. This discovery enhances our fundamental understanding of high-TOF NH 3 oxidation over Pt overlayer catalysts, which holds significance for the advancement and industrial implementation of selective NH 3 oxidation processes.