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61.
N. Dhirendra Singh Ram R. Yadav N. Venugopal Vikram Singh Akhilesh K. Yadava Krishna G. Misra Thingbaijam B. Singh Chongtham Sanjita 《Trees - Structure and Function》2016,30(5):1711-1721
Key message
Growth ring study of Pinus kesiya (khasi pine) growing in sub-tropical forest in Manipur, northeast India was performed to understand climate signatures in ring widths and intra-annual density fluctuations.Abstract
The growth rings in khasi pine (Pinus kesiya Royle ex Gordon) growing in sub-tropical Reserve Forest in Imphal, Manipur, northeast India were analysed to understand environmental signals present in ring-width series and intra-annual density fluctuations (IADFs). For this the growth ring sequences in increment core samples collected from 28 trees were precisely dated and a ring-width chronology spanning AD 1958–2014 developed. The correlation analyses between ring-width chronology and weather data of Imphal revealed that a cool April–May–June favour tree growth. The wood anatomical features of growth rings revealed the occurrence of IADFs in early- and latewoods. The IADFs in earlywood were found to be associated with reduced precipitation in months from April to July. However, the wetter conditions in late growing season, especially August/September triggered the formation of IADFs in latewood. Our findings endorse that the IADF chronologies of khasi pine could emerge as an important proxy of summer monsoon rainfall in long-term perspective in data scarce region of northeast India.62.
The delta-endotoxin of Bacillus thuringiensis subspecies kurstaki is an intracellular crystalline proteinaceous inclusion which, upon ingestion, is toxic to lepidopteran insects. Upon dissolution at pH > 9 it yields a protein subunit called protoxin. Under appropriate conditions, protoxin is hydrolyzed to a toxin molecule, which is responsible for killing the insect. It is known that this toxic activity decreases considerably above pH 10. In this study, circular dichroism spectroscopy has been used to examine the secondary structures of the protoxin and toxin molecules at different pH values to determine if there are detectable conformational changes associated with their pH-dependent functional properties. At pH 10, where toxic activity is approximately maximal, both the protoxin and toxin molecules were found to assume a conformation that is on an average approx. 26% alpha-helix and approx. 45% beta-structure. As the pH was increased above 10, where the insecticidal activity decreases, the magnitude of the CD spectrum at 222 nm decreased for protoxin and the calculated alpha-helix contents of both protoxin and toxin molecules decreased. The net secondary structure did not change significantly at pH values below 10. Significant conformational differences are observed between the secondary structure of the protoxin and toxin molecules at different pH values. The pH-dependent changes in secondary structure of the protoxin and toxin can be correlated with the effects of pH on the insecticidal activity of these proteins. 相似文献
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The interrelationship between phenological events, climatic factors, periodicity of cambial activity and seasonal production
of xylem was examined in Dillenia indica L. (Dilleniaceae) growing in sub-tropical wet forest of Meghalaya state, India. The reactivation of cambial activity was
seen in the first week of May, 15 days after sprouting of new leaves and buds. The activity of cambium and xylem production
gradually declined toward December and ceased from January to April end. There was correlation between leaf fall and cambial
dormancy. It was evident from the correlation and regression analysis, the relationship between cambial activity, xylem production
with climatic factors, the monthly mean minimum temperature plays an important role for the cambial activity and xylem production
rather than influence by rainfall and relative humidity in D. indica L. The data were discussed in the light of cambial activity, xylem production and phenological events. 相似文献
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Genome sequencing projects has led to an explosion of large amount of gene products in which many are of hypothetical proteins
with unknown function. Analyzing and annotating the functions of hypothetical proteins is important in Staphylococcus aureus
which is a pathogenic bacterium that cause multiple types of diseases by infecting various sites in humans and animals. In this
study, ten hypothetical proteins of Staphylococcus aureus were retrieved from NCBI and analyzed for their structural and functional
characteristics by using various bioinformatics tools and databases. The analysis revealed that some of them possessed functionally
important domains and families and protein-protein interacting partners which were ABC transporter ATP-binding protein,
Multiple Antibiotic Resistance (MAR) family, export proteins, Helix-Turn-helix domains, arsenate reductase, elongation factor,
ribosomal proteins, Cysteine protease precursor, Type-I restriction endonuclease enzyme and plasmid recombination enzyme
which might have the same functions in hypothetical proteins. The structural prediction of those proteins and binding sites
prediction have been done which would be useful in docking studies for aiding in the drug discovery. 相似文献
69.
Zhao Y Yao Y Xu H Lambeth L Smith LP Kgosana L Wang X Nair V 《Journal of virology》2009,83(1):489-492
Kaposi's sarcoma-associated herpesvirus-encoded microRNA (miRNA) MiR-K12-11 was recently shown to be a functional ortholog of miR-155, a miRNA that plays a major role in lymphoid malignancies and the modulation of immune responses. Here we show that miR-M4, encoded by the highly oncogenic Marek's disease virus of chickens, shares common targets with miR-155 and thus is also a functional ortholog of miR-155, the first one identified in an alphaherpesvirus. The observation that two distinct oncogenic herpesviruses associated with distinct types of lymphomas in different species encode functional miR-155 orthologs suggested the importance of this miRNA in regulatory pathways and the biology of lymphomagenesis. 相似文献
70.
The 5′ Leader of the mRNA Encoding the Marek's Disease Virus Serotype 1 pp14 Protein Contains an Intronic Internal Ribosome Entry Site with Allosteric Properties
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