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In Arabidopsis thaliana and Oryza sativa, the cytochrome P450 (CYP) 714 protein family represents a unique group of CYP monooxygenase, which functions as a shoot-specific regulator in plant development through gibberellin deactivation. Here, we report the functional characterizations of PtCYP714A3, an OsCYP714D1/Eui homologue from Populus trichocarpa. PtCYP714A3 was ubiquitously expressed with the highest transcript level in cambium-phloem tissues, and was greatly induced by salt and osmotic stress in poplar. Subcellular localization analyses indicated that PtCYP714A3-YFP fusion protein was targeted to endoplasmic reticulum (ER). Expression of PtCYP714A3 in the rice eui mutant could rescue its excessive-shoot-growth phenotype. Ectopic expression of PtCYP714A3 in rice led to semi-dwarfed phenotype with promoted tillering and reduced seed size. Transgenic lines which showed significant expression of PtCYP714A3 also accumulated lower GA level than did the wild-type (WT) plants. The expression of some GA biosynthesis genes was significantly suppressed in these transgenic plants. Furthermore, transgenic rice plants exhibited enhanced tolerance to salt and maintained more Na+ in both shoot and root tissues under salinity stress. All these results not only suggest a crucial role of PtCYP714A3 in shoot responses to salt toxicity in rice, but also provide a molecular basis for genetic engineering of salt-tolerant crops. [ABSTRACT FROM AUTHOR]

Abstract: Slip casting is a significant method and it is widely used in ceramic manufacturing. In order to investigate the influence of water processing in slurry fabrication on microstructure and oxygen permeation of Ba1.0Co0.7Fe0.2Nb0.1O3−δ (BCFN) membrane, disk-shaped membranes are made from powders with/without water processing and these membranes are checked by XRD, SEM and oxygen permeation measurement. We find barium of material dissolves into water during slurry fabrication through ICP-OES method and the A-site stoichiometric ratio is 0.986 because of the water processing, and the oxygen permeation flux of water-treated membrane is 25.2% lower than that of original membrane after sintered at 1110°C. With the increase of sintering temperature, the oxygen permeation of water-treated membrane almost recovers and is only 7% lower than the original membrane while sintered at 1150°C. A composition segregation and homogenization mechanism is proposed through microstructure and properties analysis. [Copyright &y& Elsevier]

Grain filling in maize (Zea mays) is regulated by a group of spatiotemporally synchronized transcription factors (TFs), but the factors that coordinate their expression remain unknown. We used the promoter of the grain filling-specific TF gene Opaque2 (O2) to screen upstream regulatory factors and identified a B3 domain TF, ZmABI19, that directly binds to the O2 promoter for transactivation. zmabi19 mutants displayed developmental defects in the endosperm and embryo, and mature kernels were opaque and reduced in size. The accumulation of zeins, starch and lipids dramatically decreased in zmabi19 mutants. RNA sequencing revealed an alteration of the nutrient reservoir activity and starch and sucrose metabolism in zmabi19 endosperms, and plant phytohormone signal transduction and lipid metabolism in zmabi19 embryos. Chromatin immunoprecipitation followed by sequencing coupled with differential expression analysis identified 106 high-confidence direct ZmABI19 targets. ZmABI19 directly regulates multiple key grain filling TFs including O2, Prolamine-box binding factor 1, ZmbZIP22, NAC130, and Opaque11 in the endosperm and Viviparous1 in the embryo. A number of phytohormone-related genes were also bound and regulated by ZmABI19. Our results demonstrate that ZmABI19 functions as a grain filling initiation regulator. ZmABI19 roles in coupling early endosperm and embryo development are also discussed., (© American Society of Plant Biologists 2020. All rights reserved. For permissions, please email: journals.permissions@oup.com.)