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1.
Thippeswamy T Haddley K Corness JD Howard MR McKay JS Beaucourt SM Pope MD Murphy D Morris R Hökfelt T Quinn JP 《Journal of neurochemistry》2007,100(3):790-801
Leukaemia inhibitory factor (LIF) and nerve growth factor (NGF) are well characterized regulators of galanin expression. However, LIF knockout mice containing the rat galanin 5' proximal promoter fragment (- 2546 to + 15 bp) driving luciferase responded to axotomy in the same way as control mice. Also, LIF had no effect on reporter gene expression in vitro, neither in the presence or absence of NGF, suggesting that other factors mediate an axotomy response from the galanin promoter. We then addressed the role of nitric oxide (NO) using NGF-deprived rat dorsal root ganglion (DRG) neuron cultures infected with viral vectors containing the above-mentioned construct, and also studied endogenous galanin expression in axotomized DRG in vivo. Blocking endogenous NO in NGF-deprived DRG cultures suppressed galanin promoter activity. Consistent with this, axotomized/NGF-deprived DRG neurons expressed high levels of neuronal NO synthase (nNOS) and galanin. Further, using pharmacological NOS blockers, or adenoviral vectors expressing dominant-negative either for nNOS or soluble guanylate cyclase in vivo and in vitro, we show that the NO-cGMP pathway induces endogenous galanin in DRG neurons. We propose that both LIF and NO, acting at different promoter regions, are important for the up-regulation of galanin, and for DRG neuron survival and regeneration after axotomy. 相似文献
2.
BACKGROUND AND AIMS: Species of the Nepenthaceae family are under-represented in studies of leaf traits and the consequent view of mineral nutrition and limitation in carnivorous plants. This study is aimed to complement existing data on leaf traits of carnivorous plants. METHODS: Physico-chemical properties, including construction costs (CC), of the assimilatory organs (leaf and pitcher) of a guild of lowland Nepenthes species inhabiting heath and/or peat swamp forests of Brunei, Northern Borneo were determined. KEY RESULTS: Stoichiometry analyses indicate that Nepenthes species are nitrogen limited. Most traits vary appreciably across species, but greater variations exist between the assimilatory organs. Organ mass per unit area, dry matter tissue concentration (density), nitrogen (N), phosphorus (P), carbon, heat of combustion (H(c)) and CC values were higher in the leaf relative to the pitcher, while organ thickness, potassium (K) and ash showed the opposite trend. Cross-species correlations indicate that joint rather than individual consideration of the leaf and the pitcher give better predictive relationships between variables, signalling tight coupling and functional interdependence of the two assimilatory organs. Across species, mass-based CC did not vary with N or P, but increases significantly with tissue density, carbon and H(c), and decreases with K and ash contents. Area-based CC gave the same trends (though weaker in strength) in addition to a significant positive correlation with tissue mass per unit area. CONCLUSIONS: The lower CC value for the pitcher is in agreement with the concept of low marginal cost for carnivory relative to conventional autotrophy. The poor explanatory power of N, P or N : P ratio with CC suggests that factors other than production of expensive photosynthetic machinery (which calls for a high N input), including concentrations of lignin, wax/lipids or osmoregulatory ions like K(+), may give a better explanation of the CC variation across Nepenthes species. 相似文献
3.
P. Chandra Obul Reddy G. Sairanganayakulu M. Thippeswamy P. Sudhakar Reddy M.K. Reddy Chinta Sudhakar 《Plant science》2008,175(3):372-384
Abiotic stresses adversely affect the agricultural productivity worldwide. Horsegram (Macrotyloma uniflorum (Lam.) Verdc.) is a legume crop that can tolerate severe adverse environmental conditions such as drought, salinity and heavy metal contamination. As a first step towards characterization of genes that contribute to combating abiotic stresses, construction and analysis of subtracted cDNA library is reported here. Using this strategy a total of 1050 ESTs were isolated, sequenced, 959 high quality ESTs were obtained and clustered. Further, our analysis revealed that of these 531 sequences are unique and 30% of these have no homology to known proteins in the database. This observation has great relevance since horsegram is a stress-adapted legume crop. Further, to validate the identified differentially expressed genes, expression profiles of selected clones were analyzed using reverse-northern, northern blot analysis and we show that indeed these clones are differentially expressed under various abiotic stress conditions. The implications of the analyzed genes in abiotic stress tolerance also discussed. 相似文献
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Sureshkumar Kempahanumakkagari Vanish Kumar Pallabi Samaddar Pawan Kumar Thippeswamy Ramakrishnappa Ki-Hyun Kim 《Biotechnology advances》2018,36(2):467-481
Technological advancements combined with materials research have led to the generation of enormous types of novel substrates and materials for use in various biological/medical, energy, and environmental applications. Lately, the embedding of biomolecules in novel and/or advanced materials (e.g., metal-organic frameworks (MOFs), nanoparticles, hydrogels, graphene, and their hybrid composites) has become a vital research area in the construction of an innovative platform for various applications including sensors (or biosensors), biofuel cells, and bioelectronic devices. Due to the intriguing properties of MOFs (e.g., framework architecture, topology, and optical properties), they have contributed considerably to recent progresses in enzymatic catalysis, antibody-antigen interactions, or many other related approaches. Here, we aim to describe the different strategies for the design and synthesis of diverse biomolecule-embedded MOFs for various sensing (e.g., optical, electrochemical, biological, and miscellaneous) techniques. Additionally, the benefits and future prospective of MOFs-based biomolecular immobilization as an innovative sensing platform are discussed along with the evaluation on their performance to seek for further development in this emerging research area. 相似文献
6.
Replication slippage may cause parallel evolution in the secondary structures of mitochondrial transfer RNAs 总被引:9,自引:4,他引:5
Presence of the dihydrouridine (D) stem in the mitochondrial cysteine tRNA
is unusually variable among lepidosaurian reptiles. Phylogenetic and
comparative analyses of cysteine tRNA gene sequences identify eight
parallel losses of the D-stem, resulting in D-arm replacement loops.
Sampling within the monophyletic Acrodonta provides no evidence for
reversal. Slipped-strand mispairing of noncontiguous repeated sequences
during replication or direct replication slippage can explain repeats
observed within cysteine tRNAs that contain a D-arm replacement loop. These
two mechanisms involving replication slippage can account for the loss of
the cysteine tRNA D-stem in several lepidosaurian lineages, and may
represent general mechanisms by which the secondary structures of
mitochondrial tRNAs are altered.
相似文献
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8.
G. Jyothsnakumari M. Thippeswamy G. Veeranagamallaiah C. Sudhakar 《Biologia Plantarum》2009,53(1):145-150
The relative water content (RWC), cell membrane integrity, protein pattern and the expression of late embryogenesis abundant
proteins (LEA; group 1, 2, 3 and 4) under different levels of salt stress (0, 1.0, 1.5 and 2.0 % NaCl) were investigated in
mulberry (Morus alba L.) cultivars (S1 and ATP) with contrasting salt tolerance. RWC and membrane integrity decreased with increase in NaCl concentration
more in cv. ATP than in cv. S1. SDS-PAGE protein profile of mulberry leaves after the NaCl treatments showed a significant
increase in 35, 41, 45 and 70 kDa proteins and significant decrease in 14.3, 18, 23, 28, 30, 42, 47 and 65 kDa proteins. Exposure
of plants to NaCl resulted in higher accumulation of LEA proteins in S1 than ATP. The maximum content of LEA (group 3 and
4) was detected in S1 at 2.0 % NaCl, which correlates with its salt tolerance. 相似文献
9.
Screening was done for the isolation of effective lignin degraders from the forest soil samples, by providing lignin as a carbon source through the enrichment method, which leads to the isolation of 8 effective fungal isolates among 14 isolates. Submerged fermentation was done for the production of ligninolytic enzymes with the effective microorganisms by providing Guiaicol as a carbon source. The assay of laccase, lignin peroxidise activity and specific activity was done after the incubation intervals of 2, 4, 6, 7, 8, 10 and 12 days at 27±2℃ under shake culture condition. Partially purified protein content was estimated by using Lowry's method. Pleurotus sp. and Phanerochaetae chrysosporium are more effective at the 2nd and 7th days of incubation for the production of laccase and lignin peroxidases among the effective isolates. 相似文献
10.
The complete cDNA sequence and protein reading frame of a developmentally
regulated hemocyanin subunit in the Dungeness crab (Cancer magister) is
presented. The protein sequence is aligned with 18 potentially homologous
hemocyanin-type proteins displaying apparent sequence similarities.
Functional domains are identified, and a comparison of predicted
hydrophilicities, surface probabilities, and regional backbone
flexibilities provides evidence for a remarkable degree of structural
conservation among the proteins surveyed. Parsimony analysis of the protein
sequence alignment identifies four monophyletic groups on the arthropodan
branch of the hemocyanin gene tree: crustacean hemocyanins, insect
hexamerins, chelicerate hemocyanins, and arthropodan prophenoloxidases.
They form a monophyletic group relative to molluscan hemocyanins and
nonarthropodan tyrosinases. Arthropodan prophenoloxidases, although
functionally similar to tyrosinases, appear to belong to the arthropodan
hexamer- type hemolymph proteins as opposed to molluscan hemocyanins and
tyrosinases.
相似文献