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Intron exon boundary junctions in human genome have in-built unique structural and energetic signals
Akhilesh Mishra Priyanka Siwach Pallavi Misra Simran Dhiman Ashutosh
Kumar Pandey Parul Srivastava B Jayaram 《Nucleic acids research》2021,49(5):2674
Precise identification of correct exon–intron boundaries is a prerequisite to analyze the location and structure of genes. The existing framework for genomic signals, delineating exon and introns in a genomic segment, seems insufficient, predominantly due to poor sequence consensus as well as limitations of training on available experimental data sets. We present here a novel concept for characterizing exon–intron boundaries in genomic segments on the basis of structural and energetic properties. We analyzed boundary junctions on both sides of all the exons (3 28 368) of protein coding genes from human genome (GENCODE database) using 28 structural and three energy parameters. Study of sequence conservation at these sites shows very poor consensus. It is observed that DNA adopts a unique structural and energy state at the boundary junctions. Also, signals are somewhat different for housekeeping and tissue specific genes. Clustering of 31 parameters into four derived vectors gives some additional insights into the physical mechanisms involved in this biological process. Sites of structural and energy signals correlate well to the positions playing important roles in pre-mRNA splicing. 相似文献
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Nitika Arora Renu Bhardwaj Priyanka Sharma Hardesh Kumar Arora 《Acta Physiologiae Plantarum》2008,30(6):833-839
The effects of 28-homobrassinolide (28-homoBL) on seedling growth, lipid peroxidation and antioxidative enzyme activities
in the seedlings of Zea mays L. (var. Partap-1) under salt (NaCl) stress were studied. The surface-sterilized seeds were germinated in petriplates containing
different concentrations of NaCl (25, 50, 75 and 100 mM) only, 28-homoBL (10−7, 10−9 and 10−11 M) only and NaCl supplemented with 28-homoBL for 7 days. The activities of superoxide dismutase (SOD, EC 1.15.1.1), guaiacol
peroxidase (POD, EC 1.11.1.7), catalase (CAT, EC 1.11.1.6), ascorbate peroxidase (APOX, EC 1.11.1.11) and glutathione reductase
(EC 1.6.4.2) were analysed in 7 day-old seedlings. It was observed that 28-homoBL treatments reduced the toxicity of salt
on seedling growth considerably. Lipid peroxidation level was significantly increased under saline stress, but lowered with
28-homoBL applications revealing less oxidative damage. Further 28-homoBL treatments to the seedlings showed an enhancement
in activities of SOD, POD, CAT and APOX. The activities of all antioxidative enzymes were further increased in seedlings treated
with solution containing 28-homoBL and salt together as compared to seedlings treated with different concentration of salt
solution only. 相似文献
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Priyanka Saha Subhendu Bandyopadhyay Sarmistha Sen Raychaudhuri 《Biological trace element research》2011,140(2):225-243
A nutrient medium has been formulated by altering the macro- and micro-elemental concentration in the culture medium for in
vitro somatic embryo induction of economically important medicinal plant Plantago ovata Forsk .A comparison was made between induced embryos with normal embryos (produced in Murashige and Skoog (MS) medium) to
observe frequency of embryo induction and also to determine regeneration efficiency. In the present investigation, three different
media have been formulated. Among them, FM3 (formulated media, treatment 3) was the most suitable for increasing the frequency
of somatic embryo production and regeneration of P. ovata Forsk. Better result was obtained using formulated medium than with MS medium. 相似文献
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Sunil K. Agarwal Anoop Misra Priyanka Aggarwal Amit Bardia Ruchika Goel Naval K. Vikram Jasjeet S. Wasir Nazia Hussain Krithika Ramachandran Ravindra M. Pandey 《Obesity (Silver Spring, Md.)》2009,17(5):1056-1061
Waist circumference (WC) has been advocated as a simple, reliable, and cost‐effective measure to understand an individual's cardio‐metabolic risk. Although several protocols exist for measuring WC, the variation induced by a few factors has not been investigated. We compared several established and experimental WC measurement protocols to identify factors that may cause variations in WC measurement. In this cross‐sectional study, we examined the variations in the measurement of waist circumference (WC) measures carried out in 11 ways differing by anatomical site, posture, respiratory phase, and time since last meal, using repeated measure analysis of variance (using mixed models) after Tukey‐Kramer adjustment. We estimated the proportion of variance in percentage of body fat (%BF) and fat‐free mass (FFM) explained by each of the WC measures. We studied 123 apparently healthy Asian Indians (75 females), with mean (s.d.) age of 34 (8.7) years and BMI of 23.9 (4.8) kg/m2. Overall, the mean of WCs measured using the 11 protocols were statistically different. Further, post hoc analysis showed statistically significant, yet mostly small, differences between most of the pairs. No single WC measure explained highest variance in %BF or FFM for both genders. Although, the National Institute of Health (NIH), USA, protocol was convenient and may be less prone to errors, at present it does not control for many variables tested in this study. Measures of WC measured using different protocols were statistically different. We suggest that the site of measurement, posture, phase of respiration, and time since last meal should be standardized for the development of a protocol for measurement of WC for worldwide use. 相似文献
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Taxus wallichiana Zucc. is a high valued medicinal plant and has been mainly studied for its anti-cancer properties. However, research on its other important biological activities, such as its antimicrobial potential, still needs attention. The focus of the present study is to investigate the antimicrobial activity of secondary metabolites of T. wallichiana needles against 3 different groups of microorganisms, i. e., bacteria, actinobacteria, and fungi. Bioactive compounds from T. wallichiana needles were separated through column chromatography, and, TLC-bioautography. Mobile phases were optimized using Snyder's selectivity triangle. Antimicrobial spots were fractionated and compounds were identified by gas chromatography-mass spectroscopy (GC/MS) and liquid chromatography-mass spectrometry (LC/MS). Functional groups were characterized using Fourier transform infrared spectrometry (FTIR) and nuclear magnetic resonance (NMR) was used to identify the molecular structures. GC/MS and LC/MS data analysis confirm the presence of fatty acids (arachidic acid, behenic acid, palmitic acid, and stearic acid), vitamins (nicotinamide), and alkaloids (cinchonine, timolol), aminobenzamides (procainamide), carbocyclic sugar (myoinositol), and alkane hydrocarbon (hexadecane), having antimicrobial activity in the needles of T. wallichiana. To the best of our knowledge, this is the first report on the isolation and characterization of antimicrobial compounds from the needles of Taxus wallichiana (Himalayan yew). The data obtained from the present study will be supportive to the new drug discoveries in modern medicine with various combinations of medicinal plant's active constituents that can be used for curing many diseases. 相似文献