Plant growth and development are highly coordinated by hormones, including brassinosteroid (BR) and gibberellin (GA). Although much progress has been made in understanding the fundamental signaling transduction in BR and GA, their relationship remains elusive in rice. Here, we show that BR suppresses the level of OsmiR159d, which cleaves the target OsGAMYBL2 gene. The OsmiR159d-OsGAMYBL2 pair functions as an early BR-responsive module regulating the expression of BU1, a BR-regulated gene involved in BR signaling, and CPS1 and GA3ox2, two genes in GA biosynthesis, by binding to the promoters of these genes. Furthermore, OsGSK2, a key negative player in BR signaling, interacts with OsGAMYBL2 and prevents it from being degraded under 24-epibrassinolide treatment, whereas SLR1, a rice DELLA protein negatively regulating GA signaling, interacts with OsGAMYBL2 and prevents OsGAMYBL2 from binding to the target gene promoter. GA signaling induces degradation of OsGAMYBL2 and, consequently, enhances BR signaling. These results demonstrate that a BR-responsive module acts as a common component functioning in both BR and GA pathways, which connects BR signaling and GA biosynthesis, and thus coordinates the regulation of BR and GA in plant growth and development.

Epoxides of soybean oil methyl esters (SMEs) are biodegradable, non-toxic, and renewable epoxy plasticizers. The objective of the present work was to investigate the effects of free fatty acids on the enzymatic epoxidation of SMEs. The results showed that the epoxidation of SMEs depended on the type of the added free fatty acid. For saturated ( C 18:0 ) and monounsaturated free fatty acids, the epoxy oxygen group content (EOC) of SMEs increased with increasing carbon chain length of free fatty acids; for branched-chain unsaturated free fatty acids, the EOC of SMEs decreased in the presence of hydroxyl group (OH) and hydroperoxide (OOH) of free fatty acids; the EOC of SMEs decreased with increasing number of double bonds of free fatty acids. The maximum EOC and the initial epoxidization rate (V 0 ) linearly decreased with increasing peroxide value of SMEs. The highest EOC (6.87 AE 0.3%) of SMEs was obtained using behenic acid as reaction material, which was similar with that of stearic acid (EOC 6.75 AE 0.2%).

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Chromium oxide coatings are chemically inert, have high mechanical strength, hardness and good optical characteristics; therefore, they have been widely used in many applications including corrosion protection, [1] wear resistance, [2] electronics, [3] and optics. [4] Cr 2 O 3 is well suited for wear resistance applications, as it is one of the hardest oxides with 29.5 GPa hardness. [5] Several deposition techniques have been tried for making these coatings. Cr 2 O 3 coating hardness can vary substantially due to compositional and microstructural variations, depending on the deposition method. Hardness of a plasma-sprayed Cr 2 O 3 coating, 50 lm thick was about 14.7 GPa, while a 200 nm thick RF-sputtered chromium oxide coating, stoichiometrically close to Cr 2 O 3 , exhibited 30 GPa hardness combined with good scratch resistance. [6] Even for the bulk Cr 2 O 3 , hardness values reported were from 9 GPa to 29.5 GPa. [5,7,8] Hones et al. investigated a correlation between the hardness and the sputtering deposition parameters, [2] i.e. oxygen partial pressure and substrate temperature, and found favorable deposition conditions with an oxygen partial pressure of about 15-20 % of the total sputtering gas pressure at substrate temperatures exceeding 500 K.Good coating adhesion is required for wear and corrosion resistance applications. Premature failure can occur for many reasons including coating delamination, cracking and plastic deformation. In addition to this, thin ceramic PVD coatings usually have columnar grain structure with micro cracks, pinholes, transient grain boundaries and often high throughcoating porosity, which all lead to accelerated pitting corrosion and failure at the coating/substrate interface, especially in hostile environments. [9][10][11][12] On the other hand, several studies showed that coating thickness plays an important role in enhancing both PVD-coated tool cutting performance and resistance to abrasive and erosive wear. [13] Graded systems have been employed to obtain thicker coatings without losing performance in terms of coating adhesion and toughness. [14] It is likely that thicker coatings will improve corrosion resistance in aqueous environments by eliminating through-thickness pin-hole defects.Coating mechanical, adhesion and wear properties are strongly affected by microstructure. Interfaces with high adhesion are known to ensure prolonged coating life and good wear resistance. [15] Sputtered coating microstructure and physical characteristics depend on the deposition parameters. [15][16][17] Also, substrate surface conditions prior to deposition, characterized by surface roughness, stress and oxidation state, play an important role in controlling coating properties. [16,17] In this paper SEM and TEM techniques were used to characterize thicker chromium oxide coating interfacial microstructure as a step towards developing a unique method for depositing thicker coatings with small grains, smooth surface and low residual stress. ExperimentalChromium oxide coatings were deposited on ...

Odd-numbered primary alcohols are components of plant cuticular wax, but their biosynthesis remains unknown.We isolated a rice wax crystal-sparse leaf 5 (WSL5) gene using a map-based cloning strategy. The function of WSL5 was illustrated by overexpression and knockout in rice, heterologous expression in Arabidopsis and transient expression in tobacco leaves.WSL5 is predicted to encode a cytochrome P450 family member CYP96B5. The wsl5 mutant lacked crystalloid platelets on the surface of cuticle membrane, and its cuticle membrane was thicker than that of the wild-type. The wsl5 mutant is more tolerant to drought stress. The load of C 23 -C 33 alkanes increased, whereas the C 29 primary alcohol reduced significantly in wsl5 mutant and WSL5 knockout transgenic plants. Overexpression of WSL5 increased the C 29 primary alcohol and decreased alkanes in rice leaves. Heterologous expression of WSL5 increased the C 29 primary alcohol and decreased alkanes, secondary alcohol, and ketone in Arabidopsis stem wax. Transient expression of WSL5 in tobacco leaves also increased the production C 29 primary alcohol.WSL5 catalyzes the terminal hydroxylation of alkanes, yielding odd-numbered primary alcohols, and is involved in the formation of epidermal wax crystals on rice leaf, affecting drought sensitivity.

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