Insights into microRNA-mediated interaction and regulation of metabolites in tomato.

microRNAs direct regulation of various metabolic pathways in plants and animals. miRNAs may be useful in developing novel/elite genotypes, with enhanced metabolites and disease resistance. We examined miRNAs in tomato. In tomato, miRNAs in the carotenoid pathway have not been fully elucidated. We examined the potential role of miRNAs in biosynthesis of carotenoids, transcript profiling of miRNAs and their possible targets (genes and transcription factors) at different development stages of tomato using stem-loop PCR and RT-qPCR. We also identified miRNAs targeting key flavonoid genes, such as chalcone isomerase (CHI), and dihydroflavonol-4-reductase (DFR). Distinct expression profiles of miRNAs and their targets were found in fruits of three tomato accessions, suggesting carotenoid regulation by miRNAs at various stages of fruit development. This was also confirmed using HPLC of the carotenoids. The present study may help in understanding possible regulation of carotenoid biosynthesis. The identified miRNAs can be exploited to enhance biosynthesis of different carotenoids in plants.

A comprehensive review of the pharmacological potential of Crocus sativus and its bioactive apocarotenoids.

Crocus sativus is an herbaceous plant that belongs to family Iridaceae. It is commonly known as saffron and has been used for medicinal purposes since many centuries in India and other parts of the world. Saffron of commercial importance comprises of dried stigmas of the plant and is rich in flavonoids, vitamins, and carotenoids. Carotenoids represent the main components of saffron and their cleavage results in the formation of apocarotenoids such as crocin, picrocrocin, and safranal. Studies conducted during the past two decades have revealed the immense therapeutic potential of saffron. Most of the therapeutic properties are due to the presence of unique apocarotenoids having strong free radical scavenging activity. The mode of action of these apocarotenoids could be: modulatory effects on detoxifying enzymes involved in combating oxidative stress, decreasing telomerase activity, increased the proapoptotic effect, inhibition of DNA, RNA and protein synthesis, and by a strong binding capacity of crocetin with tRNA. The present review focuses on the therapeutic role of saffron and its bio oxidative cleavage products and also highlights the possible molecular mechanism of action. The findings reported in this review describes the wide range of applications of saffron and attributes its free radical scavenging nature the main property which makes this spice a potent chemotherapeutic agent for the treatment of various diseases.

Cellulolytic Activity of Thermophilic Bacilli Isolated from Tattapani Hot Spring Sediment in North West Himalayas.

Eight thermophilic bacterial strains were isolated from Tattapani Hot spring and screened for various hydrolytic enzymes including cellulases. The isolated bacterial strains were identified as Geobacillus thermodenitrificans IP_WH1(KP842609), Bacillus licheniformis IP_WH2(KP842610), B. aerius IP_WH3(KP842611), B. licheniformis IP_WH4(KP842612), B. licheniformis IP_60Y(KP842613), G. thermodenitrificans IP_60A1(KP842614), Geobacillus sp. IP_60A2(KP842615) and Geobacillus sp. IP_80TP(KP842616) after 16S ribotying. Out of the eight isolates Geobacillus sp. IP_80TP grew best at 80 °C whereas rest of the isolates showed optimal growth at 60 °C. G. thermodenitrificans IP_WH1 produced a thermotolerant cellulase with maximum activity at 60 °C.

Mechanism of gene amplification via yeast autonomously replicating sequences.

The present investigation was aimed at understanding the molecular mechanism of gene amplification. Interplay of fragile sites in promoting gene amplification was also elucidated. The amplification promoting sequences were chosen from the Saccharomyces cerevisiae ARS, 5S rRNA regions of Plantago ovata and P. lagopus, proposed sites of replication pausing at Ste20 gene locus of S. cerevisiae, and the bend DNA sequences within fragile site FRA11A in humans. The gene amplification assays showed that plasmid bearing APS from yeast and human beings led to enhanced protein concentration as compared to the wild type. Both the in silico and in vitro analyses were pointed out at the strong bending potential of these APS. In addition, high mitotic stability and presence of TTTT repeats and SAR amongst these sequences encourage gene amplification. Phylogenetic analysis of S. cerevisiae ARS was also conducted. The combinatorial power of different aspects of APS analyzed in the present investigation was harnessed to reach a consensus about the factors which stimulate gene expression, in presence of these sequences. It was concluded that the mechanism of gene amplification was that AT rich tracts present in fragile sites of yeast serve as binding sites for MAR/SAR and DNA unwinding elements. The DNA protein interactions necessary for ORC activation are facilitated by DNA bending. These specific bindings at ORC promote repeated rounds of DNA replication leading to gene amplification.

Molecular characterization of repetitive DNA sequences from B chromosome in Plantago lagopus L.

In Plantagolagopus the B chromosome has been reported by our laboratory to be the result of massive amplification of ribosomal DNA sequences. However, the presence of transposable elements and other repetitive DNA sequences together with rDNA could not be ruled out. The present study clearly demonstrated the presence of transposable elements in the B chromosomes. These transposable elements were characterized and their nature assessed. Physical mapping using double fluorescent in situ hybridization was performed using DNA probes for 5S and copia elements. The results clearly proved that the B chromosome is a mix of 5S, 45S rDNA and transposable elements. Based on the FISH and Fiber-FISH patterns, it can be concluded that while 45S rDNA sequences are restricted to the subtelomeric regions, the 5S rDNA sequences are interspersed with transposons in the body of the B chromosome. These results have further enhanced our understanding of the organization and evolution of B chromosomes.

Risk factors and survival analysis of the esophageal cancer in the population of Jammu, India.

OBJECTIVE: To identify the risk factors of esophageal cancer and study their effect on the survival rates patients of Jammu region, India. MATERIALS AND METHODS: Detailed information was collected on socio-demographic, dietary and clinico-pathological parameters for 200 case control pairs. Discrete (categorical) data of 2 independent groups (control and cases) were summarized in frequency (%) and compared by using Chi-square (χ2 ) test. The mean age of two independent groups was compared by independent Student's t-test. To find out potential risk factor (s), the variable (s) found significant in univariate analysis were further subjected to multivariate logistic regression analysis. The association of potential risk factors with patients survival (3-year overall survival) was done by Kaplan-Meier survival curve analysis using Log-rank test. A 2-tailed (a = 2) P < 0.05 was considered statistically significant. RESULTS: Out of the 63 response parameters, seven were found highly significant on multivariate analysis. The mean (± SD) age was 56.74 ± 10.76 years, the proportions of males were higher than females, mostly illiterate and lower income group. Among dietary characteristics, snuff was highest (OR = 3.86, 95% CI = 2.46-6.08) followed by salt tea (OR = 2.53, 95% CI = 1.49-4.29), smoking (OR = 1.97, 95% CI = 1.18-3.30), sundried food (OR = 1.77, 95% CI = 1.10-2.85) and red chilly (OR = 1.76, 95% CI = 1.07-2.89). Probability of survival lowered significantly (P < 0.05 or P < 0.01 or P < 0.001) in those consuming tobacco in the form of snuff (Log-rank c 2 = 24.62, P = 0.000) and smoking (Log-rank c 2 = 5.20, P = 0.023) as compared to those who did not take these. CONCLUSIONS: The analysis finally established snuff (smokeless tobacco) as the most powerful risk factor of esophageal cancer in Jammu region, followed by the salt tea, smoking and the sundried food.

Distribution of eu- and heterochromatin in Plantago ovata.

Plantago ovata (2n = 8) is the only cultivated species in the monotypic genus Plantago. The seed husk of the plant constitutes the psyllium (Isabgol) which has many medicinal properties. The 1C DNA content was determined to be 0.635 pg (621 Mb) with an AT content of 59.7%. Applying Giemsa C-banding and fluorescence in situ hybridization (FISH) using the Cot-1 fraction of DNA on prometaphase and metaphase chromosomes we investigated the chromosomal distribution of eu- and heterochromatin. All applied techniques revealed that the euchromatin is located at the distal ends of all chromosome arms, besides the NOR-bearing ones. Interestingly, in addition one arm of chromosome 1 seems to be entirely euchromatic. Furthermore, we have analysed the correlation between the global distribution of histone H3 mono-, di- or trimethylated at either lysine 4, 9 or 27 and the microscopically detectable eu- and heterochromatin. Methylated H3K4 was found to be enriched exclusively within euchromatin. From the other tested methylation marks only H3K9me1, H3K9me2 and H3K27me1 showed, in addition to a more or less disperse labelling, an enrichment within the heterochromatic chromocentres. The cell cycle dependent phosphorylation of histone H3 at serine 10 and threonine 11 was enriched in all pericentromeric regions.

PGC-1alpha Thr394Thr and Gly482Ser variants are significantly associated with T2DM in two North Indian populations: a replicate case-control study.

The recent observations that Peroxisome proliferator activated receptor gamma coactivator 1 alpha (PGC1A) is responsible for the induction of reactive oxygen species (ROS) detoxifying agents and that ROS triggers insulin resistance, support the role that this gene could play in the onset of Type 2 diabetes mellitus (T2DM). Two PGC1A variants Thr394Thr (rs2970847) and Gly482Ser (rs8192673) were genotyped in 822 subjects (351 T2DM cases and 471 controls) from two North Indian populations, represented as Group 1 (Kashmir population) and Group 2 (Punjab and Jammu population). Both Groups 1 and 2 showed a significant association of Thr394Thr variant with T2DM after applying Bonferroni corrections (P=0.001 and 0.012, respectively). Logistic regression analysis for Thr394Thr susceptible genotypes together (rs2970847 G/A and A/A) conferred a 1.89-(95%CI 1.25-2.85) fold higher risk for T2DM in Group 1 and 1.81-(95%CI 1.19-2.78) fold risk in Group 2. The susceptible, Ser482 (rs8192673 G/A and A/A) genotypes, gave a 2.04 (95%CI 1.47-3.03) fold higher risk for T2DM in Group 1. Mitochondrial genotype backgrounds observed in association with T2DM (Bhat et al. 2007), when studied in combination with PGC1A variants, showed an increased prevalence in controls with mt10398G and 16189T along with G/G genotype background at the two polymorphic loci of PGC1A. These observations suggest that the two genotype backgrounds together could provide protection against T2DM.

The possible role of 10398A and 16189C mtDNA variants in providing susceptibility to T2DM in two North Indian populations: a replicative study.

The role of mitochondria in causing diseases is becoming evident as more and more studies are focusing on this organelle of the cell. This is largely attributed to its reactive oxygen species (ROS) production property. In the context of diabetes, ROS is suggested to trigger different forms of insulin resistance involving different mechanisms. The suggestive role of a mtDNA variant G10398A in increasing ROS production and the impaired response to oxidative stress due to T16189C variant is worth addressing as genetic susceptibility factors in type 2 diabetes mellitus (T2DM). A case control study on 312 T2DM cases and ethnically matched 466 controls involving two North Indian populations, referred as cohort 1 and cohort 2 (in a replicative study), was undertaken to test such a genetic association. A statistically significant association was observed for 10398A allele in both the cohorts [cohort1 (OR = 2.67 95% CI 1.77-4.00); cohort2 (OR = 1.76 95%CI 1.12-2.77)]. The analysis of G10398A/T16189C haplotypic combinations revealed that 10398A/16189C haplotype provides a risk in both the cohorts. To sum up the study suggests that 10398A and 16189C alleles provide susceptiblity to T2DM independently as well as together.

Genetic diversity among Plantagos : 17. A novel trisomic in Plantago lagopus.

In the progenies of the crosses between disomics and trisomies, two plants were isolated which carried an extra chromosome that was unlike any in the standard complement. The plants were not alike; while one carried a metacentric, the other had a telocentric extra chromosome. Their detailed structure and possible modes of origin are discussed.

Renal function after long term treatment with lithium.

Renal functions of 30 patients of manic depressive psychosis on long term lithium prophylaxis have been studied and compared with 15 age and sex matched patients receiving psychotropic drugs other than lithium. The urine output more than 2.5 L/day was seen in 12 patients (4(1% ) while impaired capacity to show urinary osmolality more than 500 m Osm/L after overnight fluid deprivation was seen in 6 patients. Creatinine clearance ranged between 70-106 ml/min (mean 89 ml/mt). Creatinine clearance less than 70 ml/nun was seen in 3 patients. The ratio of urinary and serum creatinine showed statistically significant (p< .001) low value in lithium treated group. There was also significant increase in mean uric acid excretion in patients on lithium therapy. It is recommended that inspite of serum lithium levels being in normal range, renal functions should be assessed regularly in order to avoid progressive impairment of renal functions.