Genome-wide and expression analysis of protein phosphatase 2C in rice and Arabidopsis

<p>Abstract</p> <p>Background</p> <p>The protein phosphatase 2Cs (PP2Cs) from various organisms have been implicated to act as negative modulators of protein kinase pathways involved in diverse environmental stress responses and developmental processes. A genome-wide overview of the PP2C gene family in plants is not yet available.</p> <p>Results</p> <p>A comprehensive computational analysis identified 80 and 78 PP2C genes in <it>Arabidopsis thaliana </it>(AtPP2Cs) and <it>Oryza sativa </it>(OsPP2Cs), respectively, which denotes the PP2C gene family as one of the largest families identified in plants. Phylogenic analysis divided PP2Cs in Arabidopsis and rice into 13 and 11 subfamilies, respectively, which are supported by the analyses of gene structures and protein motifs. Comparative analysis between the PP2C genes in Arabidopsis and rice identified common and lineage-specific subfamilies and potential 'gene birth-and-death' events. Gene duplication analysis reveals that whole genome and chromosomal segment duplications mainly contributed to the expansion of both OsPP2Cs and AtPP2Cs, but tandem or local duplication occurred less frequently in Arabidopsis than rice. Some protein motifs are widespread among the PP2C proteins, whereas some other motifs are specific to only one or two subfamilies. Expression pattern analysis suggests that 1) most PP2C genes play functional roles in multiple tissues in both species, 2) the induced expression of most genes in subfamily A by diverse stimuli indicates their primary role in stress tolerance, especially ABA response, and 3) the expression pattern of subfamily D members suggests that they may constitute positive regulators in ABA-mediated signaling pathways. The analyses of putative upstream regulatory elements by two approaches further support the functions of subfamily A in ABA signaling, and provide insights into the shared and different transcriptional regulation machineries in dicots and monocots.</p> <p>Conclusion</p> <p>This comparative genome-wide overview of the PP2C family in Arabidopsis and rice provides insights into the functions and regulatory mechanisms, as well as the evolution and divergence of the PP2C genes in dicots and monocots. Bioinformatics analyses suggest that plant PP2C proteins from different subfamilies participate in distinct signaling pathways. Our results have established a solid foundation for future studies on the functional divergence in different PP2C subfamilies.</p

Low Cost, Robust, Environmentally Friendly Geopolymer–Mesoporous Carbon Composites for Efficient Solar Powered Steam Generation

High-efficiency, environment friendly, renewable energy-based methods of desalination represent attractive and potentially very powerful solutions to the long-standing problem of global water shortage. Many new laboratory-scale materials have been developed for photothermal desalination but the development of low-cost, easy-to-manufacture, and scalable materials and systems that can convert solar irradiation into exploitable thermal energy in this context is still a significant challenge. This paper presents work on a geopolymer–biomass mesoporous carbon composite (GBMCC) device with mesoporous and macroporous structures for harvesting solar energy, which is then used in a device to generate water vapor with high efficiency using negative pressure, wind-driven, steam generation. The GBMCC device gives water evaporation rates of 1.58 and 2.71 kg m−2 h−1 under 1 and 3 suns illumination, with the solar thermal conversion efficiency up to 84.95% and 67.6%, respectively. A remarkable, record high water vapor generation rate of 7.55 kg m−2 h−1 is achieved under 1 sun solar intensity at the wind speed of 3 m s−1. This is a key step forward todays efficient, sustainable and economical production of clean water from seawater or common wastewater with free solar energy

5,5′-Bis(diethyl­amino)-2,2′-[butane-1,4-diyldioxy­bis(nitrilo­methyl­idyne)]­diphenol

The title complex, C26H38N4O4, was synthesized by the reaction of 4-diethyl­amino-2-hydroxy­benzaldehyde with 1,4-bis­(amino­oxy)butane in ethanol. It crystallizes as discrete centrosymmetric molecules adopting an extended conformation where the two salicylaldoxime groups are separated from each other. Intra­molecular O—H⋯N hydrogen bonding is observed between the hydr­oxy groups and oxime N atoms. Inter­molecular π–π stacking inter­actions [3.979 (2) Å] between aromatic rings are apparent in the crystal structure. Each ethyl group is disordered over two positions; in one the site occupancy factors are 0.55 and 0.45, in the other 0.53 and 0.47