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151.
Bilachi S Ravindranath Venkatappa Krishnamurthy Venkatarangaiah Krishna Kahale Bommaiah Lingaiah Vasudevanayaka 《Bioinformation》2013,9(12):605-609
Chlamydophila pneumoniae, the causative agent of chronic obstructive pulmonary disease (COPD), is presently the fifth mortality
causing chronic disease in the world. The understanding of disease and treatment options are limited represents a severe concern
and a need for better therapeutics. With the advancements in the field of complete genome sequencing and computational
approaches development have lead to metabolic pathway analysis and protein-protein interaction network which provides vital
evidence to the protein function and has been appropriate to the fields such as systems biology and drug discovery. Protein
interaction network analysis allows us to predict the most potential drug targets among large number of the non-homologous
proteins involved in the unique metabolic pathway. A computational comparative metabolic pathway analysis of the host H.
sapiens and the pathogen C pneumoniae AR39 has been carried out at three level analyses. Firstly, metabolic pathway analysis was
performed to identify unique metabolic pathways and non-homologous proteins were identified. Secondly, essentiality of the
proteins was checked, where these proteins contribute to the growth and survival of the organism. Finally these proteins were
further subjected to predict protein interaction networks. Among the total 65 pathways in the C pneumoniae AR39 genome 10 were
identified as the unique metabolic pathways which were not found in the human host, 32 enzymes were predicted as essential and
these proteins were considered for protein interaction analysis, later using various criteria''s we have narrowed down to prioritize
ribonucleotide-diphosphate reductase subunit beta as a potential drug target which facilitate for the successful entry into drug
designing. 相似文献
152.
Summary The cation exchange capacity (C.E.C.) in sett roots (30 days) and shoot roots (95 days and 135 days) in six high yielding and five low-yielding hybrid sugarcane varieties was determined and the results are presented. A high positive correlation (r+0.87) was found to exist between sett root C.E.C. and yield of cane in tons/acre. There was no significant difference between the occasions of sampling. The useful role of C.E.C. as an yield index in large scale progeny testing in economic breeding programmes in this crop is indicated. 相似文献
153.
154.
Jesse Tack Rakesh K. Singh Lawton L. Nalley Basavaraj C. Viraktamath Saraswathipura L. Krishnamurthy Nate Lyman Krishna S. V. Jagadish 《Global Change Biology》2015,21(4):1668-1678
Flooded rice is grown across wide geographic boundaries from as far north as Manchuria and as far south as Uruguay and New South Wales, primarily because of its adaptability across diverse agronomic and climatic conditions. Salt‐stress damage, a common occurrence in delta and coastal rice production zones, could be heightened by the interactions between high temperature and relative humidity (vapor pressure deficit – VPD). Using temporal and spatial observations spanning 107 seasons and 19 rice‐growing locations throughout India with varying electrical conductivity (EC), including coastal saline, inland saline, and alkaline soils, we quantified the proportion of VPD inducing salinity damage in rice. While controlling for time‐invariant factors such as trial locations, rice cultivars, and soil types, our regression analysis indicates that EC has a nonlinear detrimental effect on paddy rice yield. Our estimates suggest these yield reductions become larger at higher VPD. A one standard deviation (SD) increase in EC from its mean value is associated with 1.68% and 4.13% yield reductions at median and maximum observed VPD levels, respectively. Yield reductions increase roughly sixfold when the one SD increase is taken from the 75th percentile of EC. In combination, high EC and VPD generate near catastrophic crop loss as predicted yield approaches zero. If higher VPD levels driven by global warming materialize in conjunction with rising sea levels or salinity incursion in groundwater, this interaction becomes an important and necessary predictor of expected yield losses and global food security. 相似文献
155.
Construction of a genetic linkage map and mapping of drought tolerance trait in Indian beveragial tea 总被引:1,自引:0,他引:1
156.
157.
Mohammad Adnan Siddiqui Krishnamurthy Malathi 《The Journal of biological chemistry》2012,287(52):43651-43664
Autophagy is a tightly regulated mechanism that mediates sequestration, degradation, and recycling of cellular proteins, organelles, and pathogens. Several proteins associated with autophagy regulate host responses to viral infections. Ribonuclease L (RNase L) is activated during viral infections and cleaves cellular and viral single-stranded RNAs, including rRNAs in ribosomes. Here we demonstrate that direct activation of RNase L coordinates the activation of c-Jun N-terminal kinase (JNK) and double-stranded RNA-dependent protein kinase (PKR) to induce autophagy with hallmarks as accumulation of autophagic vacuoles, p62(SQSTM1) degradation and conversion of Microtubule-associated Protein Light Chain 3-I (LC3-I) to LC3-II. Accordingly, treatment of cells with pharmacological inhibitors of JNK or PKR and mouse embryonic fibroblasts (MEFs) lacking JNK1/2 or PKR showed reduced autophagy levels. Furthermore, RNase L-induced JNK activity promoted Bcl-2 phosphorylation, disrupted the Beclin1-Bcl-2 complex and stimulated autophagy. Viral infection with Encephalomyocarditis virus (EMCV) or Sendai virus led to higher levels of autophagy in wild-type (WT) MEFs compared with RNase L knock out (KO) MEFs. Inhibition of RNase L-induced autophagy using Bafilomycin A1 or 3-methyladenine suppressed viral growth in initial stages; in later stages autophagy promoted viral replication dampening the antiviral effect. Induction of autophagy by activated RNase L is independent of the paracrine effects of interferon (IFN). Our findings suggest a novel role of RNase L in inducing autophagy affecting the outcomes of viral pathogenesis. 相似文献
158.
A molecular machine biosensor: construction, predictive models and experimental studies 总被引:1,自引:0,他引:1
This paper describes the construction, operation and predictive modeling of a molecular machine, functioning as a high sensitivity biosensor. Embedded gramicidin A (gA) ionchannels in a self-assembled tethered lipid bilayer act as biological switches in response to target molecules and provide a signal amplification mechanism that results in high sensitivity molecular detection. The biosensor can be used as a rapid and sensitive point of care diagnostic device in different media such as human serum, plasma and whole blood without the need for pre and post processing steps required in an enzyme-linked immunosorbent assay. The electrical reader of the device provides the added advantage of objective measurement. Novel ideas in the construction of the molecular machine, including fabrication of biochip arrays, and experimental studies of its ability to detect analyte molecules over a wide range of concentrations are presented. Remarkably, despite the complexity of the device, it is shown that the response can be predicted by modeling the analyte fluid flow and surface chemical reactions. The derived predictive models for the sensing dynamics also facilitate determining important variables in the design of a molecular machine such as the ion channel lifetime and diffusion dynamics within the bilayer lipid membrane as well as the bio-molecular interaction rate constants. 相似文献
159.
Exposure of Bacillus subtilis to a shear rate of 1,482/s leads to a rapid loss of cell viability after 10 h of growth. Biochemical and molecular evidences provided below strongly suggest that cell death under high shear results from an apoptosis-like process similar to that described in eukaryotes, with activation of a caspase-3-like protease (C(3)LP) followed by DNA fragmentation. Shear stress leads to an increase in specific intracellular reactive oxygen species (siROS), possibly through activation of NADH oxidase (NOX). The formation of siROS precedes the activation of C(3)LP and DNA fragmentation, thus establishing siROS as the molecular link between shear stress and apoptosis-like cell death. A model is proposed in which NOX is viewed as being strategically placed on the plasma membrane of B. subtilis that senses and converts a mechanical force arising from shear stress into a chemical signal leading to activation of C(3)LP, DNA fragmentation, and thus, apoptosis-like cell death. 相似文献
160.
Molinaro RJ Jha BK Malathi K Varambally S Chinnaiyan AM Silverman RH 《Nucleic acids research》2006,34(22):6684-6695
The antiviral and antitumor functions of RNase L are enabled by binding to the allosteric effectors 5′-phosphorylated, 2′,5′-linked oligoadenylates (2-5A). 2-5A is produced by interferon-inducible 2′,5′-oligoadenylate synthetases (OAS) upon activation by viral double-stranded RNA (dsRNA). Because mutations in RNase L have been implicated as risk factors for prostate cancer, we sought to determine if OAS activators are present in prostate cancer cells. We show that prostate cancer cell lines (PC3, LNCaP and DU145), but not normal prostate epithelial cells (PrEC), contain RNA fractions capable of binding to and activating OAS. To identify the RNA activators, we developed a cDNA cloning strategy based on stringent affinity of RNAs for OAS. We thus identified mRNAs for Raf kinase inhibitor protein (RKIP) and poly(rC)-binding protein 2 (PCBP2) that bind and potently activate OAS. In addition, human endogenous retrovirus (hERV) envelope RNAs were present in PC3 cells that bind and activate OAS. Analysis of several gene expression profiling studies indicated that PCBP2 RNA was consistently elevated in metastatic prostate cancer. Results suggest that OAS activation may occur in prostate cancer cells in vivo stimulated by cellular mRNAs for RKIP and PCBP2. 相似文献