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61.
Thangaraj K Chaubey G Kivisild T Selvi Rani D Singh VK Ismail T Carvalho-Silva D Metspalu M Bhaskar LV Reddy AG Chandra S Pande V Prathap Naidu B Adarsh N Verma A Jyothi IA Mallick CB Shrivastava N Devasena R Kumari B Singh AK Dwivedi SK Singh S Rao G Gupta P Sonvane V Kumari K Basha A Bhargavi KR Lalremruata A Gupta AK Kaur G Reddy KK Rao AP Villems R Tyler-Smith C Singh L 《Human heredity》2008,66(1):1-9
We have analyzed 7,137 samples from 125 different caste, tribal and religious groups of India and 99 samples from three populations of Nepal for the length variation in the COII/tRNA(Lys) region of mtDNA. Samples showing length variation were subjected to detailed phylogenetic analysis based on HVS-I and informative coding region sequence variation. The overall frequencies of the 9-bp deletion and insertion variants in South Asia were 1.9 and 0.6%, respectively. We have also defined a novel deep-rooting haplogroup M43 and identified the rare haplogroup H14 in Indian populations carrying the 9-bp deletion by complete mtDNA sequencing. Moreover, we redefined haplogroup M6 and dissected it into two well-defined subclades. The presence of haplogroups F1 and B5a in Uttar Pradesh suggests minor maternal contribution from Southeast Asia to Northern India. The occurrence of haplogroup F1 in the Nepalese sample implies that Nepal might have served as a bridge for the flow of eastern lineages to India. The presence of R6 in the Nepalese, on the other hand, suggests that the gene flow between India and Nepal has been reciprocal. 相似文献
62.
Inactivation of isocitrate lyase (native and EDTA-dialysed) by excess tetranitromethane (TNM) exhibits, biphasic kinetics, in which half of the initial activity is lost in a fast and the remaining half in a slow phase each following the pseudo-first order kinetics. Rate constants of the two phases are proportional to the TNM concentration. High succinate concentration protects the enzyme against TNM inactivation only in the slow phase without any effect on the fast phase. With the EDTA-dialysed enzyme, no such protection (against inactivation by TNM) is observed in the presence of succinate or Mg2+ ions. Addition of both these ligands together brings about protection against the slow phase (as with the native enzyme). It has been proposed that the site-site heterogeneity of isocitrate lyase is a consequence of its quaternary structure constraints. 相似文献
63.
64.
A Kalinski D L Melroy R S Dwivedi E M Herman 《The Journal of biological chemistry》1992,267(17):12068-12076
We have examined the synthesis, posttranslational processing, and localization of soybean P34, a member of the papain superfamily. P34 has been identified as a constituent of oil storage organelles or oil bodies isolated from seed lysates and has been assumed to be one of the oil body proteins. Electron microscopic immunocytochemistry with a monoclonal antibody demonstrated that P34 is localized in the protein storage vacuoles but not in the oil bodies. Immunocytochemical observations of partially disrupted seed cells showed that the association of P34 with oil bodies appears to occur as a consequence of cell lysis. In vitro synthesis of P34 results in the formation of a 46-kDa polypeptide that increases to 47 kDa due to core glycosylation by canine microsomes. In vivo synthesis studies in the presence and absence of tunicamycin, an inhibitor of N-linked glycosylation, indicate that pro-P34 is 47 kDa. Since the cDNA sequence of prepro-P34 contains a single putative glycosylation site in the precursor domain, we conclude that P34, like a few other vacuolar proteins, is synthesized as a glycoprotein precursor. Pulse-chase experiments showed that the processing of pro-P34 to mature P34 occurs in a single step and that this posttranslational cleavage occurs on the carboxyl side of an Asn, which is typical of seed vacuolar proteins. Pro-P34 (47 kDa) is detected in immunoblots of maturing seeds. Analysis of RNA indicates that the P34 genes are expressed only during seed maturation and that the P34 mRNA is related to other thiol protease mRNAs detectable in other organs and plants. Unlike other seed thiol proteases that are synthesized only after seed germination, P34 accumulates during seed maturation. 相似文献
65.
V. K. Dwivedi M. Chandra P. C. Misra Aparna Misra M. K. Misra 《Journal of enzyme inhibition and medicinal chemistry》2013,28(1):43-46
Pro-oxidant and anti-oxidant systems and their levels have significant roles in occlusive vascular diseases. In the present communication, we have measured the levels of some representative anti-oxidant enzymes in the blood of the patients of myocardial infarction after reperfusion and compared them to age and sex matched healthy persons. Our findings show that the activities of anti-oxidant enzymes (viz. SOD, catalase and glutathione reductase) are significantly decreased whereas there is significant increase in the levels of malonaldialdehyde (a marker of free radical-mediated damage) in the patients. The findings point out that ischemic myocardial disorders are associated with excessive free radical generation and free radical-mediated damage of lipids. 相似文献
66.
Gaurav Dwivedi Margaret A. Gran Pritha Bagchi Melissa L. Kemp 《PLoS computational biology》2015,11(11)
Quantifying the magnitude and dynamics of protein oxidation during cell signaling is technically challenging. Computational modeling provides tractable, quantitative methods to test hypotheses of redox mechanisms that may be simultaneously operative during signal transduction. The interleukin-4 (IL-4) pathway, which has previously been reported to induce reactive oxygen species and oxidation of PTP1B, may be controlled by several other putative mechanisms of redox regulation; widespread proteomic thiol oxidation observed via 2D redox differential gel electrophoresis upon IL-4 treatment suggests more than one redox-sensitive protein implicated in this pathway. Through computational modeling and a model selection strategy that relied on characteristic STAT6 phosphorylation dynamics of IL-4 signaling, we identified reversible protein tyrosine phosphatase (PTP) oxidation as the primary redox regulatory mechanism in the pathway. A systems-level model of IL-4 signaling was developed that integrates synchronous pan-PTP oxidation with ROS-independent mechanisms. The model quantitatively predicts the dynamics of IL-4 signaling over a broad range of new redox conditions, offers novel hypotheses about regulation of JAK/STAT signaling, and provides a framework for interrogating putative mechanisms involving receptor-initiated oxidation. 相似文献
67.
Ankit Verma Dhirendra Kumar Sharma Rituparna Sarma Hasnahana Chetia Juri Saikia 《Bioinformation》2013,9(15):755-758
BDNF (Brain derived neurotrophic factor) is a secretion protein and a member of the neurotrophin family of growth factors.
Structural and functional characterization of BDNF Varanus komodoensis is of interest while its structure remains unknown. Thus, a
homology molecular model of BDNF was constructed for gleaning possible structural insights. The model was compared with the
structure of the homologous NGF (Nerve growth factor, another member of neuro-trophin family) from Naja atra. Comparative
structural analysis of the models showed structural similarities with their predicted cavities for the interpretation of potential
functional analogy. 相似文献
68.
Poonam Piplani Ankit Jain Dhiksha Devi Anuradha Sharma Pragati Silakari 《Bioorganic & medicinal chemistry》2018,26(1):215-224
The present study reports the effect of indanone derivatives on scopolamine induced deficit cholinergic neurotransmission serving as promising leads for the therapeutics of cognitive dysfunction. Eleven compounds 54–64 have been designed, synthesised and evaluated against behavioural alterations using step down passive avoidance protocol at a dose of 0.5?mg/kg with Donepezil (1) as the reference standard. All the synthesised compounds were evaluated for their in vitro acetylcholinesterase (AChE) inhibition at five different concentrations using mice brain homogenate as the source of the enzyme. Compounds 54, 56, 59 and 64 displayed appreciable activity with an IC50 value of 14.06?µM, 12.30?µM, 14.06?µM and 12.01?µM, respectively towards acetylcholinesterase inhibition. The molecular docking study performed to predict the binding mode of the compounds suggested that these compounds could bind appreciably to the amino acids present at the active site of recombinant human acetylcholinesterase (rhAChE). The behavioural, biochemical and in silico pharmacokinetic studies were in concordance with each other. 相似文献
69.
Sthitapranjya Pati Ankit Sood Sourish Mukhopadhyay Vidita A Vaidya 《Journal of biosciences》2018,43(1):85-95
The medial prefrontal cortex (mPFC) is implicated in anxiety-like behaviour. In rodent models, perturbations of mPFC neuronal activity through pharmacological manipulations, optogenetic activation of mPFC neurons or cell-type specific pharmacogenetic inhibition of somatostatin interneurons indicate conflicting effects on anxiety-like behaviour. In the present study we examined the effects of pharmacogenetic activation of Ca2+/calmodulin-dependent protein kinase α (CamKIIα)-positive excitatory neurons on anxiety-like behaviour. We used clozapine-N-oxide (CNO) to pharmacogenetically activate virally delivered CamKIIα-hM3Dq-DREADD in mPFC excitatory neurons. The effects of acute CNO or vehicle treatment on anxiety-like behaviour in the open field and elevated plus maze tests were examined in rats virally infected with either CamKIIα-hM3Dq-DREADD or CamKIIα-GFP. In addition, the effects of acute CNO treatment on the expression of the neuronal activity marker c-Fos were examined in the mPFC as well as downstream target neuronal circuits using immunohistochemistry. Acute pharmacogenetic activation of mPFC excitatory neurons evoked a significant decrease in anxiety-like behaviour selectively on the elevated plus maze task, but not the open field test. Acute CNO treatment resulted in enhanced c-Fos-immunopositive cell number in the infralimbic, prelimbic and cingulate subdivisions of the mPFC. This was also accompanied by enhanced c-Fos-immunopositive cell number in multiple downstream circuits of the mPFC in CNO-treated hM3Dq animals. Acute pharmacogenetic activation of mPFC excitatory neurons reduces anxiety-like behaviour in a task-specific fashion accompanied by enhanced c-Fos expression in the mPFC and multiple target circuits implicated in the regulation of anxiety-like behaviour. 相似文献
70.
Sandhya Dwivedi Surendra Singh U.K. Chauhan Mahendra Kumar Tiwari 《Journal of Genetic Engineering and Biotechnology》2018,16(1):133-141
In present study seven RAPD primers were used to access the diversity within and among twelve populations of three mushroom species Ganoderma lucidum, leucoagaricus sp. and Lentinus sp. Total of 111 bands were scored by 7 RAPD primers in 30 accessions of three mushroom species collected from different sampling sites of central India. Total 111 bands were generated using seven primers which were F-1, OPG-06, OPC-07, OPD-08, OPA-02, OPD-02, OPB-10. All 111 bands were polymorphic in nature (100%). Therefore, it revealed that the used primers had sufficient potency for population studies and 30 accessions had higher genetic differences among each other. In best of the knowledge, this is the first report, which accesses the genetic diversity between three mushroom species (Gd Ganoderma lucidum, Lg Leucoagaricus sp., Ls Lentinus). The polymorphic percentage ranged from 3.60 to 23% within twelve populations, while polymorphic percentage among group was 40.56, among population within groups was 41.12 and within population was 18.32. This indicated that the genetic diversity within the population was very low, but slightly higher in the populations of three species. Among three groups representing Gd., Lg and Ls, Among populations within groups shown highest percentage of variation (Pv?=?41.12) while within populations, the lowest percentage of variation (18.32) was observed. This result also support that the highest genetic variation was present among groups in comparison to among the population within a species and lowest genetic variation was observed within the population. 相似文献