Screening of Synthetic Isoxazolone Derivative Role in Alzheimer’s Disease: Computational and Pharmacological Approach

Neurochemical Research - Alzheimer's disease (AD) is age-dependent neurological disorder with progressive loss of cognition and memory. This multifactorial disease is characterized by...     

Subtractive Proteomics and Immuno-informatics Approaches for Multi-peptide Vaccine Prediction Against Klebsiella oxytoca and Validation Through In Silico Expression

International Journal of Peptide Research and Therapeutics - Klebsiella oxytoca is a gram-negative bacterium. It is opportunistic in nature and causes hospital acquired infections....     

Foliar application of ascorbic acid enhances salinity stress tolerance in barley (Hordeum vulgare L.) through modulation of morpho-physio-biochemical attributes,ions uptake,osmo-protectants and stress response genes expression

Barley (Hordeum vulgare L.) is a major cereal grain and is known as a halophyte (a halophyte is a salt-tolerant plant that grows in soil or waters of high salinity). We therefore conducted a pot experiment to explore plant growth and biomass, photosynthetic pigments, gas exchange attributes, stomatal properties, oxidative stress and antioxidant response and their associated gene expression and absorption of ions in H. Vulgare. The soil used for this analysis was artificially spiked at different salinity concentrations (0, 50, 100 and 150 mM) and different levels of ascorbic acid (AsA) were supplied to plants (0, 30 and 60 mM) shortly after germination of the seed. The results of the present study showed that plant growth and biomass, photosynthetic pigments, gas exchange parameters, stomatal properties and ion uptake were significantly (p < 0.05) reduced by salinity stress, whereas oxidative stress was induced in plants by generating the concentration of reactive oxygen species (ROS) in plant cells/tissues compared to plants grown in the control treatment. Initially, the activity of antioxidant enzymes and relative gene expression increased to a saline level of 100 mM, and then decreased significantly (P < 0.05) by increasing the saline level (150 mM) in the soil compared to plants grown at 0 mM of salinity. We also elucidated that negative impact of salt stress in H. vulgare plants can overcome by the exogenous application of AsA, which not only increased morpho-physiological traits but decreased oxidative stress in the plants by increasing activities of enzymatic antioxidants. We have also explained the negative effect of salt stress on H. vulgare can decrease by exogenous application of AsA, which not only improved morpho-physiological characteristics, ions accumulation in the roots and shoots of the plants, but decreased oxidative stress in plants by increasing antioxidant compounds (enzymatic and non-enzymatic). Taken together, recognizing AsA's role in nutrient uptake introduces new possibilities for agricultural use of this compound and provides a valuable basis for improving plant tolerance and adaptability to potential salinity stress adjustment.     

Association of the lipoprotein receptor-related protein 2 gene with gout and non-additive interaction with alcohol consumption

Introduction

The T allele of a single nucleotide polymorphism (SNP: rs2544390) in lipoprotein receptor-related protein 2 (LRP2) is associated with higher serum urate and risk of gout in Japanese individuals. SNP rs2544390 also interacts with alcohol consumption in determining hyperuricemia in this population. We investigated the association of rs2544390 with gout, and interaction with all types of alcohol consumption in European and New Zealand (NZ) Māori and Pacific subjects, and a Māori study cohort from the East Coast region of NZ’s North Island.

Methods

Rs2544390 was genotyped by Taqman®. From NZ a total of 1205 controls and 1431 gout cases clinically ascertained were used. Publicly available genotype and serum urate data were utilized from the Atherosclerosis Risk in Communities (ARIC) study and the Framingham Heart Study (FHS). Alcohol consumption data were obtained by consumption frequency questions in all study cohorts. Multivariate adjusted logistic regression was done using STATA.

Results

The T allele of rs2544390 was associated with increased risk of gout in the combined Māori and Pacific Island cohort (OR = 1.20, P = 0.009), and associated with gout in the European subjects, but with a protective effect (OR = 0.79, P_Unadjusted = 0.02). Alcohol consumption was positively associated with risk of gout in Māori and Pacific subjects (0.2% increased risk/g/week, P = 0.004). There was a non-additive interaction between any alcohol intake and the risk of gout in the combined Māori and Pacific cohorts (P_Interaction = 0.001), where any alcohol intake was associated with a 4.18-fold increased risk in the CC genotype group (P = 6.6x10^-5), compared with a 1.14-fold increased risk in the CT/TT genotype group (P = 0.40). These effects were not observed in European subjects.

Conclusions

Association of the T-allele with gout risk in the Māori and Pacific subjects was consistent with this allele increasing serum urate in Japanese individuals. The non-additive interaction in the Māori and Pacific subjects showed that alcohol consumption over-rides any protective effect conferred by the CC genotype. Further exploration of the mechanism underlying this interaction should generate new understanding of the biological role of alcohol in gout, in addition to strengthening the evidence base for reduction of alcohol consumption in the management of gout.     

Molecular enzymology of the catalytic domains of the Dnmt3a and Dnmt3b DNA methyltransferases

The C-terminal domains of the mammalian DNA methyltransferases Dnmt1, Dnmt3a, and Dnmt3b harbor all the conserved motifs characteristic for cytosine-C5 methyltransferases. Whereas the isolated catalytic domain of Dnmt1 is inactive, we show here that the C-terminal domains of Dnmt3a and Dnmt3b are catalytically active. Neither Dnmt3a nor Dnmt3b shows a significant preference for the satellite 2 sequence, although Dnmt3b is required for methylation of these regions in vivo. However, the catalytic domain of Dnmt3a methylates DNA in a distributive reaction, whereas Dnmt3b is processive, which accelerates methylation of macromolecular DNA in vitro. This property could make Dnmt3b a preferred enzyme for methylation at satellite 2 repeats, since they are highly CG-rich. We have also analyzed the catalytic activities of six different mutations found in ICF (immunodeficiency, centromeric instability, and facial abnormalities) patients in the catalytic domain of Dnmt3b. Five of them display catalytic activities reduced by 10-50-fold; one mutant was inactive in our assay (residual activity <1%). These results confirm that a reduced catalytic activity of Dnm3b causes ICF. However, the mutations in general do not completely abrogate catalytic activity. This finding may explain why ICF patients are viable, whereas nmt3b knock-out mice die during embryogenesis.     

DNA of Drosophila melanogaster contains 5-methylcytosine

It is commonly accepted that the DNA of Drosophila melanogaster does not contain 5-methylcytosine, which is essential in the development of most eukaryotes. We have developed a new, highly specific and sensitive assay to detect the presence of 5-methylcytosine in genomic DNA. The DNA is degraded to nucleosides, 5-methylcytosine purified by HPLC and, for detection by 1D- and 2D-TLC, radiolabeled using deoxynucleoside kinase and [gamma-(32)P]ATP. Using this assay, we show here that 5-methylcytosine occurs in the DNA of D. melanogaster at a level of approximately 1 in 1000-2000 cytosine residues in adult flies. DNA methylation is detectable in all stages of D.melanogaster development.     

Removal of chromium on Polyalthia longifolia leaves biomass

Adsorption is an environmental friendly process for removal and/or recovery of heavy metals from wastewater. In recent years, it has been substantiated as a popular technique to treat industrial waste effluents, with significant advantages. In this work, batchwise removal of chromium (III) ions from water by Polyalthia longifolia leaves was studied as a function of adsorbent dose, pH, contact time, and agitation speed. Surface characteristics of the leaves were evaluated by recording IR spectra. The Langmuir, Freundlich, and Temkin adsorption isotherms were employed to explain the sorption process. It was found that one gram of leaves can remove 1.87 mg of trivalent chromium when working at pH 3.0. It has been concluded that Polyalthia longifolia leaves can be used as cost-effective and benign adsorbents for removal of Cr(III) ions from wastewater.     

De novo methylation of nucleosomal DNA by the mammalian Dnmt1 and Dnmt3A DNA methyltransferases

In the cell, DNA is wrapped on histone octamers, which reduces its accessibility for DNA interacting enzymes. We investigated de novo methylation of nucleosomal DNA in vitro and show that the Dnmt3a and Dnmt1 DNA methyltransferases efficiently methylate nucleosomal DNA without dissociation of the histone octamer from the DNA. In contrast, the prokaryotic SssI DNA methyltransferase and the catalytic domain of Dnmt3a are strongly inhibited by nucleosomes. We also found that full-length Dnmt1 and Dnmt3a bind to nucleosomes much stronger than their isolated catalytic domains, demonstrating that the N-terminal parts of the MTases are required for the interaction with nucleosomes. Variations of the DNA sequence or the histone tails did not significantly influence the methylation activity of Dnmt3a. The observation that mammalian methyltransferases directly modify nucleosomal DNA provides an insight into the mechanisms by which histone tail and DNA methylation patterns can influence each other because the DNA methylation pattern can be established while histones remain associated to the DNA.     

Molecular markers in medicinal plant biotechnology: past and present

Plant based medicines have gained popularity worldwide due to their almost negligible side effects. In India, the three traditional medicinal systems, namely homeopathy, Ayurveda and Siddha rely heavily on plants for medicinal formulations. To prevent the indiscriminate collection of these valuable medicinal plants and for their proper authentication and conservation, it is imperative to go for sustained efforts towards proper germplasm cataloguing and devising conservation strategies. For this purpose, molecular markers have a significant role, as they provide information ranging from diversity at nucleotide level (single nucleotide polymorphisms) to gene and allele frequencies (genotype information), the extent and distribution of genetic diversity, and population structure. Over the past twenty years, the molecular marker field has completely transformed the meaning of conservation genetics which has emerged from a theory-based field of population biology to a full-fledged pragmatic discipline. In this review, we have explored the transition and transformation of molecular marker technologies throughout these years.     

Low Levels of GSTA1 Expression Are Required for Caco-2 Cell Proliferation

The colonic epithelium continuously regenerates with transitions through various cellular phases including proliferation, differentiation and cell death via apoptosis. Human colonic adenocarcinoma (Caco-2) cells in culture undergo spontaneous differentiation into mature enterocytes in association with progressive increases in expression of glutathione S-transferase alpha-1 (GSTA1). We hypothesize that GSTA1 plays a functional role in controlling proliferation, differentiation and apoptosis in Caco-2 cells. We demonstrate increased GSTA1 levels associated with decreased proliferation and increased expression of differentiation markers alkaline phosphatase, villin, dipeptidyl peptidase-4 and E-cadherin in postconfluent Caco-2 cells. Results of MTS assays, BrdU incorporation and flow cytometry indicate that forced expression of GSTA1 significantly reduces cellular proliferation and siRNA-mediated down-regulation of GSTA1 significantly increases cells in S-phase and associated cell proliferation. Sodium butyrate (NaB) at a concentration of 1 mM reduces Caco-2 cell proliferation, increases differentiation and increases GSTA1 activity 4-fold by 72 hours. In contrast, 10 mM NaB causes significant toxicity in preconfluent cells via apoptosis through caspase-3 activation with reduced GSTA1 activity. However, GSTA1 down-regulation by siRNA does not alter NaB-induced differentiation or apoptosis in Caco-2 cells. While 10 mM NaB causes GSTA1-JNK complex dissociation, phosphorylation of JNK is not altered. These findings suggest that GSTA1 levels may play a role in modulating enterocyte proliferation but do not influence differentiation or apoptosis.