Plants are highly sensitive to temperature and can perceive a difference of as little as 1°C. How temperature is sensed and integrated in development is unknown. In a forward genetic screen in
...Arabidopsis, we have found that nucleosomes containing the alternative histone H2A.Z are essential to perceiving ambient temperature correctly. Genotypes deficient in incorporating H2A.Z into nucleosomes phenocopy warm grown plants, and show a striking constitutive warm temperature transcriptome. We show that nucleosomes containing H2A.Z display distinct responses to temperature in vivo, independently of transcription. Using purified nucleosomes, we are able to show that H2A.Z confers distinct DNA-unwrapping properties on nucleosomes, indicating a direct mechanism for the perception of temperature through DNA-nucleosome fluctuations. Our results show that H2A.Z-containing nucleosomes provide thermosensory information that is used to coordinate the ambient temperature transcriptome. We observe the same effect in budding yeast, indicating that this is an evolutionarily conserved mechanism.
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► In
Arabidopsis, developmental responses to temperature are mediated by histone H2A.Z ► H2A.Z nucleosome occupancy decreases with increasing temperature ► H2A.Z regulates gene expression via effects on DNA accessibility ► Regulation of the temperature transcriptome by H2A.Z is conserved in budding yeast
Seed birth to death Kumar, S. P. Jeevan; Prasad, S. Rajendra; Banerjee, Rintu ...
Annals of botany,
09/2015, Letnik:
116, Številka:
4
Journal Article
Recenzirano
Odprti dostop
Reactive oxygen species (ROS) are considered to be detrimental to seed viability. However, recent studies have demonstrated that ROS have key roles in seed germination particularly in the release of ...seed dormancy and embryogenesis, as well as in protection from pathogens.
This review considers the functions of ROS in seed physiology. ROS are present in all cells and at all phases of the seed life cycle. ROS accumulation is important in breaking seed dormancy, and stimulating seed germination and protection from pathogens. However, excessive ROS accumulation can be detrimental. Therefore, knowledge of the mechanisms by which ROS influence seed physiology will provide insights that may not only allow the development of seed quality markers but also help us understand how dormancy can be broken in several recalcitrant species.
Reactive oxygen species have a dual role in seed physiology. Understanding the relative importance of beneficial and detrimental effects of ROS provides great scope for the improvement and maintenance of seed vigour and quality, factors that may ultimately increase crop yields.
Perceiving and detecting a sustainable source of energy is very critical issue for current modern society. Hydrogen on combustion releases energy and water as a byproduct and has been considered as ...an environmental pollution free energy carrier. From the last decade, most of the researchers have recommended hydrogen as one of the cleanest fuels and its demand is rising ever since. Hydrogen having the highest energy density is more advantageous than any other fuel. Hydrogen obtained from the fossil fuels produces carbon dioxide as a byproduct and creates environment negative effect. Therefore, biohydrogen production from green algae and cyanobacteria is an attractive option that generates a benign renewable energy carrier. Microalgal feedstocks show a high potential for the generation of fuel such as biohydrogen, bioethanol and biodiesel. This article has reviewed the different methods of biohydrogen production while also trying to find out the most economical and ecofriendly method for its production. A thorough review process has been carried out to study the methods, enzymes involved, factors affecting the rate of hydrogen production, dual nature of algae, challenges and commercialization potential of algal biohydrogen.
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•Microalgae are a third-generation biofuel feedstock.•Hydrogenases and nitrogenases produce biohydrogen in microalgae.•Biohydrogen biorefinery can be useful for reducing cost for its production.•Challenges and improvements of hydrogen production have also been discussed.
Wireless Sensor Networks (WSNs) are applicable in numerous domains, including industrial automation where WSNs may be used for monitoring and control of industrial plants and equipment. However, the ...requirements in the industrial systems differ from the general WSN requirements. In recent years, standards have been defined by several industrial alliances. These standards are specified as frameworks with modifiable parts that can be defined based on the particular application of WSN. However, limited work has been done on defining industry-specific protocols that could be used as a part of these standards. In this survey, we discuss representative protocols that meet some of the requirements of the industrial applications. Since the industrial applications domain in itself is a vast area, we divide them into classes with similar requirements. We discuss these industrial classes, set of common requirements and various state-of-the-art WSN standards proposed to satisfy these requirements. We then present a broader view towards the WSN solution by discussing important functions like medium access control, routing, and transport in detail to give some insight into specific requirements and the classification of protocols based on certain factors. We list and discuss representative protocols for each of these functions that address requirements defined in the industrial classes. Security function is discussed in brief, mainly in relation to industrial standards. Finally, we identify unsolved challenges that are encountered during design of protocols and standards. In addition some new challenges are introduced and discussed.
Plant growth and development are strongly affected by small differences in temperature. Current climate change has already altered global plant phenology and distribution, and projected increases in ...temperature pose a significant challenge to agriculture. Despite the important role of temperature on plant development, the underlying pathways are unknown. It has previously been shown that thermal acceleration of flowering is dependent on the florigen, FLOWERING LOCUS T (FT). How this occurs is, however, not understood, because the major pathway known to upregulate FT, the photoperiod pathway, is not required for thermal acceleration of flowering. Here we demonstrate a direct mechanism by which increasing temperature causes the bHLH transcription factor PHYTOCHROME INTERACTING FACTOR4 (PIF4) to activate FT. Our findings provide a new understanding of how plants control their timing of reproduction in response to temperature. Flowering time is an important trait in crops as well as affecting the life cycles of pollinator species. A molecular understanding of how temperature affects flowering will be important for mitigating the effects of climate change.
The objective of the current study is to synthesize a library consisting of four sets of phenothiazine incorporated 1,2,3-triazole compounds using molecular hybridization approach. In total, 36 new ...hybrid molecules were synthesized and screened for in vitro growth inhibition activity against Mycobacterium tuberculosis H37Rv strain (ATCC-27294). Among the tested compounds, nineteen compounds exhibited significant activity with MIC value 1.6 μg/mL, which is twofold higher than the MIC value of standard first-line TB drug Pyrazinamide. In addition, all these compounds are proved to be non-toxic (with selective index > 40) against VERO cell lines. However, these compounds did not inhibit significantly the growth of Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa strains: the activity profile is similar to that observed for standard anti-TB drugs (isoniazid and pyrazinamide), indicating the specificity of these compounds towards the Mycobacterium tuberculosis strain. Also, we report the molecular docking studies against two target enzymes (Inh A and CYP121) to further validate the antitubercular potency of these molecules. Furthermore, prediction of in silico-ADME and pharmacokinetic parameters indicated that these compounds have good oral bioavailability. The results suggest that these phenothiazine incorporated 1,2,3-triazole compounds are a promising class of molecular entities for the development of new antitubercular leads.
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•36 New Phenothiazine incorporated 1,2,3-triazole hybrids are synthesized.•Click chemistry protocol is followed for the synthesis.•19 Compounds exhibit potent antiTB activity (MIC = 1.6 μg/mL).•Compounds are non-toxic to normal cells.•Compounds exhibit strong binding interactions with target enzymes, InhA and CYP121.
•Photocatalytic applications of WO3 and Bi2WO6 based nanomaterial are reviewed.•Modifications to improve their performance are highlighted.•Charge carrier generation–separation–recombination is ...discussed.•Challenges and future prospects in this area are addressed.
Heterogeneous photocatalysis is an ideal green energy technology for the purification of wastewater. Although titania dominates as the reference photocatalyst, its wide band gap is a bottleneck for extended utility. Thus, search for non-TiO2 based nanomaterials has become an active area of research in recent years. In this regard, visible light absorbing polycrystalline WO3 (2.4–2.8eV) and Bi2WO6 (2.8eV) with versatile structure-electronic properties has gained considerable interest to promote the photocatalytic reactions. These materials are also explored in selective functional group transformation in organic reactions, because of low reduction and oxidation potential of WO3 CB and Bi2WO6 VB, respectively. In this focused review, various strategies such as foreign ion doping, noble metal deposition and heterostructuring with other semiconductors designed for efficient photocatalysis is discussed. These modifications not only extend the optical response to longer wavelengths, but also prolong the life-time of the charge carriers and strengthen the photocatalyst stability. The changes in the surface-bulk properties and the charge carrier transfer dynamics associated with each modification correlating to the high activity are emphasized. The presence of oxidizing agents, surface modification with Cu2+ ions and synthesis of exposed facets to promote the degradation rate is highlighted. In depth study on these nanomaterials is likely to sustain interest in wastewater remediation and envisaged to signify in various green energy applications.
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•UAE had higher lipid content 43 ± 0.33% (w/w) than Soxhlet (30 ± 0.28) and BS (36 ± 0.38).•Lipid content of 43 ± 0.33% (w/w) obtained in 20 min at 30 °C, 50 Hz frequency and ...2800 W.•UAE maintained quality of lipids on par with conventional lipid extraction.•UAE is a greener technique, which reduced time, energy and solvent consumption.
Soaring demand for alternative fuels has been gaining wide interest due to depletion of conventional fuel, increasing petroleum prices and greenhouse gas emissions. Biodiesel, an alternative fuel, derived from oleaginous microbes has been promising because of short incubation time and easy to scale up. Oleaginous yeast Trichosporon sp. is capable of utilizing glycerol and agro-residues for enhanced lipid synthesis. Lipid extraction from Trichosporon sp. biomass showed highest lipid content with ultrasonic assisted extraction (43 ± 0.33%, w/w) coupled with process parameters than the conventional Soxhlet (30 ± 0.28%, w/w) and Binary solvent choloroform:methanol, (2:1, v/v) methods (36 ± 0.38%, w/w), respectively. The standardized process parameters of ultrasonic assisted extraction coupled with chloroform/methanol solvent system resulted 95–97% of conversion efficiency in 20 min at 30 °C with a frequency of 50 Hz and 2800 W power, respectively. Enzymatic transesterification of yeast biomass lipid obtained 85% of fatty acid methyl esters that are predominant with oleic acid methyl ester followed by palmitic and stearic acid methyl esters, respectively. These results substantiate that the ultrasonic assisted extraction is a potential green extraction technique that had reduced time, energy and solvent consumption without compromising on lipid quality. Deploying this green extraction technique could make the biodiesel production process inexpensive and eco-friendly.
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