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991.
In the present study Dof1 gene of finger millet was cloned and sequenced. In silico analysis reveals 61% identity with the
Sorghum bicolor and 57% identity with the Oryza sativa Dof1 sequence. A comparative analysis of gene sequences from different crops and three finger millet genotypes {Brown (PRM-1),
Golden (PRM-701) and White (PRM-801)} differing in grain colour, yield and photosynthetic efficiency showed a high degree
of sequence identity of Dof1 sequence gene ranging from 22 to 70% as evident from distance matrix of the built phylogenetic
tree showing two major clusters. A total of five conserved motifs were observed in Dof1 sequences of different cereals. Motif
1 with multilevel consensus sequence CKNCRRYWTKGGAMRNVPVG contains zinc finger Dof domain. Motif 3 and motif 5 contains protein
kinase phosphorylation site. Motif 2 contains Dof domain and zinc finger N-glycosylation site while motif 4 is involved in Zinc finger type profiling. Further, we studied the spatial distribution
of Dof1 gene in three vegetative tissues (root, stem and flag leaf) as well as four stages of developing spikes (S1, S2, S3
and S4) of the three finger millet genotypes using qualitative and quantitative PCR based approaches. Physiological parameters
(plant height, leaf area, chlorophyll content, SPAD value and photosynthetic efficiency) at the time of flowering was found
to be highest in white (PRM-801) genotype followed by golden (PRM-701) and brown (PRM-1) genotype. Semi-quantitative RT-PCR
and quantitative real-time PCR analysis revealed that the expression of Dof1 is highest in leaves and lowest in roots, which
suggests its role in regulation of photosynthesis-related genes and carbon skeleton synthesis. Also at grain maturity stage,
expression of Dof1 was higher in white (PRM-801) genotype followed by golden (PRM-701) and brown (PRM-1) genotype. The result
is suggestive of Dof1 role in the accumulation of grain protein and yield attribute through regulation of key enzymes involved
in source to sink relationship during grain filling stage. 相似文献
992.
Shukla D Kesari R Mishra S Dwivedi S Tripathi RD Nath P Trivedi PK 《Plant cell reports》2012,31(9):1687-1699
Phytochelatin synthase (PCS), the key enzyme involved in heavy metal detoxification and accumulation has been used from various sources to develop transgenic plants for the purpose of phytoremediation. However, some of the earlier studies provided contradictory results. Most of the PCS genes were isolated from plants that are not potential metal accumulators. In this study, we have isolated PCS gene from Ceratophyllum demersum cv. L. (CdPCS1), a submerged rootless aquatic macrophyte, which is considered as potential accumulator of heavy metals. The CdPCS1 cDNA of 1,757?bp encodes a polypeptide of 501 amino acid residues and differs from other known PCS with respect to the presence of a number of cysteine residues known for their interaction with heavy metals. Complementation of cad1-3 mutant of Arabidopsis deficient in PC (phytochelatin) biosynthesis by CdPCS1 suggests its role in the synthesis of PCs. Transgenic tobacco plants expressing CdPCS1 showed several-fold increased PC content and precursor non-protein thiols with enhanced accumulation of cadmium (Cd) and arsenic (As) without significant decrease in plant growth. We conclude that CdPCS1 encodes functional PCS and may be part of metal detoxification mechanism of the heavy metal accumulating plant C. demersum. KEY MESSAGE: Heterologous expression of PCS gene from C. demersum complements Arabidopsis cad1-3 mutant and leads to enhanced accumulation of Cd and As in transgenic tobacco. 相似文献
993.
Tiwari VK Tewari N Katiyar D Tripathi RP Arora K Gupta S Ahmad R Srivastava AK Khan MA Murthy PK Walter RD 《Bioorganic & medicinal chemistry》2003,11(8):1789-1800
A series of N(1),N(n)-xylofuranosylated diaminoalkanes (3-9 and 11-18) has been synthesized either by reductive amination of deoxy xylouloses (2a, 2b) with amines followed by one pot reduction with NaBH(4) or NaCNBH(3); or by 1,4-conjugate addition of amines to glycosyl olefinic esters (10a, 10b). The compounds were screened for their interference with filarial worms' glutathione metabolism, a potential target for chemotherapeutic attack. Interestingly, these compounds affected intracellular glutathione, gamma-glutamyl cysteine synthetase, glutathione reductase and glutathione-S-transferase(s) of bovine filarial worms to varying degrees. Some of the compounds though effected the motility and MTT reduction potential of filarial worms Brugia malayi, however, little microfilaricidal and macrofilaricidal were noted with compounds at 50mg/kg oral dose. Compounds 6, 16 and 17 were evaluated also for in vivo activity. 相似文献
994.
Ireson CR Parish D Purohit A Woo LW Potter BV Chander SK Reed MJ 《The Journal of steroid biochemistry and molecular biology》2003,84(2-3):337-342
Steroid sulphatase inhibitors which decrease or prevent the biosynthesis of oestrogens, potentially have an important role in the treatment of breast cancer in postmenopausal women. The non-steroidal sulphatase inhibitor 667 COUMATE has been shown to be active both in vitro and in vivo. The pharmacokinetics of this drug have not been investigated. In preparation for the clinical evaluation of this agent, a sensitive and robust reversed phase high-performance liquid chromatography (HPLC) method was developed for the detection of 667 COUMATE in biological fluids. The sulphatase inhibitor was extracted from plasma with diethyl ether and separated from putative metabolites and endogenous plasma components with a C3-phenyl column. Using this method an extraction efficiency of 76+/-5% and a limit of detection of less than 0.1 ng/ml was achieved. The stability of this agent was investigated under different pH conditions and during storage in plasma at room temperature or -20 degrees C. 667 COUMATE was found to be stable when stored in acidified plasma (pH 4.5) at -20 degrees C. In conclusion, the HPLC method developed is a reproducible and sensitive assay that will enable quantitation of the potent non-steroidal sulphatase inhibitor 667 COUMATE in biological fluids in the forthcoming Phase I clinical trial. 相似文献
995.
996.
Shinagare AB Ramaiya NH Bellizzi AM Mayer RJ 《Pancreatology : official journal of the International Association of Pancreatology (IAP) ... [et al.]》2012,12(1):35-38
Anaplastic pancreatic carcinoma (APC) is a rare, aggressive variant of pancreatic ductal adenocarcinoma. Surgery is the preferred treatment whenever possible, however APC is often unresectable at presentation and prognosis remains poor. We present a case of APC which showed a marked initial response to FOLFIRINOX with decreased size and increased cystic change, however then rapidly progressed with innumerable hepatic metastases after five months of FOLFIRINOX treatment. Although there is limited data on use of FOLFIRINOX in locally advanced pancreatic adenocarcinoma, it remains an attractive option in comparison to radiotherapy and 5-fluorouracil. 相似文献
997.
Roderick H Tripathi L Babirye A Wang D Tripathi J Urwin PE Atkinson HJ 《Molecular Plant Pathology》2012,13(8):842-851
Plant parasitic nematodes impose a severe constraint on plantain and banana productivity; however, the sterile nature of many cultivars precludes conventional breeding for resistance. Transgenic plantain cv. Gonja manjaya (Musa AAB) plants, expressing a maize cystatin that inhibits nematode digestive cysteine proteinases and a synthetic peptide that disrupts nematode chemoreception, were assessed for their ability to resist nematode infection. Lines were generated that expressed each gene singly or both together in a stacked defence. Nematode challenge with a single species or a mixed population identified 10 lines with significant resistance. The best level of resistance achieved against the major pest species Radopholus similis was 84% ± 8% for the cystatin, 66% ± 14% for the peptide and 70% ± 6% for the dual defence. In the mixed population, trial resistance was also demonstrated to Helicotylenchus multicinctus. A fluorescently labelled form of the chemodisruptive peptide underwent retrograde transport along certain sensory dendrites of R. similis as required to disrupt chemoreception. The peptide was degraded after 30 min in simulated intestinal fluid or boiling water and after 1 h in nonsterile soil. In silico sequence analysis suggests that the peptide is not a mammalian antigen. This work establishes the mode of action of a novel nematode defence, develops the evidence for its safe and effective deployment against multiple nematode species and identifies transgenic plantain lines with a high level of resistance for a proposed field trial. 相似文献
998.
Lam HY Clark MJ Chen R Chen R Natsoulis G O'Huallachain M Dewey FE Habegger L Ashley EA Gerstein MB Butte AJ Ji HP Snyder M 《Nature biotechnology》2012,30(1):78-82
Whole-genome sequencing is becoming commonplace, but the accuracy and completeness of variant calling by the most widely used platforms from Illumina and Complete Genomics have not been reported. Here we sequenced the genome of an individual with both technologies to a high average coverage of ~76×, and compared their performance with respect to sequence coverage and calling of single-nucleotide variants (SNVs), insertions and deletions (indels). Although 88.1% of the ~3.7 million unique SNVs were concordant between platforms, there were tens of thousands of platform-specific calls located in genes and other genomic regions. In contrast, 26.5% of indels were concordant between platforms. Target enrichment validated 92.7% of the concordant SNVs, whereas validation by genotyping array revealed a sensitivity of 99.3%. The validation experiments also suggested that >60% of the platform-specific variants were indeed present in the genome. Our results have important implications for understanding the accuracy and completeness of the genome sequencing platforms. 相似文献
999.
R Gupta A Ratan C Rajesh R Chen HL Kim R Burhans W Miller S Santhosh RV Davuluri A Butte SC Schuster S Seshagiri G Thomas 《BMC genomics》2012,13(1):440
ABSTRACT: BACKGROUND: With over 1.3 billion people, India is estimated to contain three times more genetic diversity than does Europe. Next-generation sequencing technologies have facilitated the understanding of diversity by enabling whole genome sequencing at greater speed and lower cost. While genomes from people of European and Asian descent have been sequenced, only recently has a single male genome from the Indian subcontinent been published at sufficient depth and coverage. In this study we have sequenced and analyzed the genome of a South Asian Indian female (SAIF) from the Indian state of Kerala. RESULTS: We identified over 3.4 million SNPs in this genome including over 89,873 private variations. Comparison of the SAIF genome with several published personal genomes revealed that this individual shared ~50% of the SNPs with each of these genomes. Analysis of the SAIF mitochondrial genome showed that it is closely related to the U1 haplogroup which has been previously observed in Kerala. We assessed the SAIF genome for SNPs with health and disease consequences and found that the individual was at a higher risk for multiple sclerosis and a few other diseases. In analyzing SNPs that modulate drug response we found a variation that predicts a favorable response to metformin, a drug used to treat diabetes. SNPs predictive of adverse reaction to warfarin indicated that the SAIF individual is not at risk for bleeding if treated with typical doses of warfarin. In addition, we report the presence of several additional SNPs of medical relevance. CONCLUSIONS: This is the first study to report the complete whole genome sequence of a female from the state of Kerala in India. The availability of this complete genome and variant will further aid studies aimed at understanding genetic diversity, identifying clinically relevant changes and accessing disease burden in the Indian population. 相似文献
1000.
Prinja S Bahuguna P Pinto AD Sharma A Bharaj G Kumar V Tripathy JP Kaur M Kumar R 《PloS one》2012,7(1):e30362