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The complementary DNA encoding WAP65 protein was cloned from the liver of two fish species sea bass (Dicentrarchus labrax) and sea bream (Sparus aurata). Full-length cDNA sequences were obtained from reverse transcribed total RNA, followed by 5′ and 3′ rapid amplification of cDNA end (RACE) experiments. The full-length cDNA sequence of D. labrax is 1709 bp and the coding sequence is flanked by a 67 bp 5′-UTR and a 358 bp 3′-UTR. The full-length cDNA sequence of S. aurata is 1599 bp, and the coding sequence is flanked by a 48 bp 5′-UTR and a 273 bp 3′-UTR. The deduced amino acid putative primary sequences are composed of 427 and 425 amino acid residues for D. labrax and S. aurata, respectively. They display high homologies with previously described fish WAP65 and other hemopexin-like proteins from rabbit (Oryctolagus cuniculus). Expression of Wap65 has proved to be a natural physiological adaptive answer of teleost fish to warm temperature acclimation. In all fish species studied to date, Wap65 was found expressed mainly by the liver, although other tissues seem able to express Wap65 in response to a warm temperature acclimation, in a specie specific manner. Here, we investigate the tissue specific expression of Wap65 in D. labrax and S. aurata in response to a warm temperature acclimation, by RT-PCR analysis.  相似文献   

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Nostocacean cyanobacteria are one of the important components of paddy fields due to their ability to fix atmospheric nitrogen and supply phytohormones for crop growth. In this study, 13 Nostoc strains isolated from paddy soils in Vietnam were classified using a polyphasic approach. The results showed a high diversity of the isolated strains that represented seven morphotypes corresponding to five genotypes, with 16S rRNA gene sequence similarity values ranging between 94.97–99.78% compared to the available sequences from GenBank. Bioassay assessment revealed that 11 out of 13 strains possessed antibacterial activities, three of which exhibited cytotoxic activities on MCF7 and HCT116 cells with an IC50 ranging from 47.8 μg mL?1 to 232.0 μg mL?1. Interestingly, strains with identical 16S rRNA gene sequences displayed different antibacterial and cytotoxic activity profiles.  相似文献   

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Ductal lavage (DL) and random periareolar fine needle aspiration (RPFNA) have both been proposed as minimally invasive techniques to sample breast tissue during breast cancer prevention trials. Laser capture microdissection (LCM), linear RNA amplification and quantitative real-time polymerase chain reaction (qPCR) theoretically overcome the limitations of small specimen size obtained with DL and RPFNA. In order to test the yield, relative stability and amplifiability of RNA from fixed and archived RPFNA and DL specimens, breast tissue was sampled from individual high risk women (n = 9) by both DL and RPFNA. RPFNA samples showed good RNA/cDNA yield and amplification while only 2 of 9 of the paired DL specimens had cDNA of adequate quality for subsequent PCR. One and two rounds of linear amplification provided approximately a 200- and 20,000-fold enrichment of RNA, respectively. PCR analysis consistently detected ER and COX-1 mRNA in the majority of RPFNA samples examined while pS2, PCNA, VEGF and survivin expression varied with subject. RNA yield and/or stability was greater for fixed and archived RPFNA than DL specimens of breast tissue. In a subsequent study examining an expanded biomarker gene panel in fixed vs. frozen RPFNA samples, mRNA profiles and ranked relative mRNA abundance were similar (r = 0.89) for frozen and fixed RPFNA specimens. In summary, frozen RPFNA samples may be optimal for RNA endpoints in human breast cancer prevention trials but fixed RPFNA specimens allow similar analyses with greater convenience.  相似文献   

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A 9S poly(A)-RNA preparation isolated from mouse embryos was shown to stimulate the synthesis of histones in an ascites cell free extract. This RNA preparation was used for the synthesis of a highly labelled cDNA probe complementary to histone mRNA. Hybridisation of this cDNA probe to rRNA showed that 52% of the cDNA consisted of sequences complementary to rRNA. The histone mRNA specific cDNA was purified by hybridising the impure cDNA to rRNA followed by removal of the single-stranded histone cDNA by hydroxylapatite chromatography.  相似文献   

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《Mycological Research》2006,110(6):697-704
Double-stranded (ds) RNA banding patterns were determined in 21 wild-type strains of the soilborne plant pathogen Chalara elegans originating from different geographic regions worldwide. Five strains, each with a unique dsRNA pattern, were selected for cDNA cloning, northern blot analysis and dsRNA transmission experiments. Four strains contained multiple (up to 6) dsRNA elements (2.0 kbp to 12 kbp in size) and one strain contained a single 2.8 kbp fragment. These five strains were distinguished from one another by their unique RAPD-PCR patterns. Seven partial cDNA clones were derived from the predominant 2.8, 5.3, and 12 kbp dsRNA elements. Nucleotide sequence analysis and northern blot hybridizations revealed a high degree of genetic dissimilarity among the different molecular-size dsRNA elements, even those found within a single strain. Four clones from the 5.3 kbp dsRNA fragment showed a 23-43 % amino acid identity to either the coat protein or RNA-dependent RNA polymerase regions of viruses in the Totiviridae. One clone from the 2.8 kbp dsRNA fragment had a 55-57 % amino acid identity to the RdRp region of viruses in the Narnaviridae. Two clones from the 12 kbp dsRNA fragment showed no significant homology to any known virus group. Colonies derived from 100 single-conidia isolates of C. elegans strains with the 2.8, 5.3 and 12 kbp elements all contained the corresponding dsRNA element, indicating that dsRNA transmission through conidia was highly efficient, regardless of molecular size. However, transmission of dsRNA between the mycelium of strains of C. elegans could not be achieved in this study. Genetically unique strains carrying diverse dsRNA elements appear to have evolved within populations of C. elegans. Based on our findings, there are at least 3 groups of viruses present in C. elegans.  相似文献   

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Samia cynthia ricini is a commercial silk-producing insect that is now reared year-round in Korea, with the expectation of being utilized for diverse purposes. In this report, we present the complete mitochondrial genome (mitogenome) of S. c. ricini. The 15,384-bp long S. cynthia ricini mitogenome was amplified into 26 short fragments using three long overlapping fragments using primers designed from reported lepidopteran mitogenome sequences. The genome comprises 37 genes (13 protein-coding genes, two rRNA genes, and 22 tRNA genes), and one large non-coding region termed the A + T-rich region. The A/T content of the third codon position was 91.7%, which was 18.8% and 21.6% higher than those of first and second codon positions, respectively. The high A/T content in the genome is reflected in codon usage, accounting for 39.5% of A/T-composed codons (TTA, ATT, TTT, and ATA). Unlike a previous report on the start codon for the COI gene, the S. c. ricini COI gene commences with a typical ATT codon. A total of 221 bp of non-coding sequences are dispersed in 17 regions, ranging in size from 1 to 54 bp, which comprise 1.4% of the total genome. One of the non-coding sequence located between tRNAGln and ND2 (54 bp) has 77% sequence homology with the 5′-sequence of the neighboring ND2 gene, suggesting partial duplication of the sequence during evolution. The 361-bp long A + T-rich region contains an 18 bp-long poly-T stretch, ATAGA motif, ATTTA element, microsatellite-like A/T sequence, poly-A stretch and one tRNA-like sequence, as typically found in Lepidoptera including Bombycoidea.  相似文献   

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《Process Biochemistry》2007,42(2):180-187
In this study, the diversity of planctomycete-like bacteria and the presence of anaerobic ammonia-oxidizing bacteria in the aerobic and anaerobic basins of a full-scale alcohol manufacturing wastewater treatment plant were examined by cloning and sequencing of PCR-amplified partial 16S rRNA genes. Two clone libraries were constructed by using a 16S rRNA-targeted universal reverse primer and a forward PCR primer specific for planctomycetes. Phylogenetic analysis of 63 16S rRNA gene sequences defined 52 operational taxonomic units (OTUs). The majority of these sequences (51.6%) clustered in two separated monophyletic groups distantly within the planctomycete tree. 15.9% sequences were related to some uncultured planctomycetes and branched as a monophyletic cluster from the described four genera (planctomyces, Pirellula, Isosphaera and Gemmata) of Planctomycetales with similarity of 81–89% to the cultured Planctomyces. More interestingly, 17.5% sequences (most retrieved from the anaerobic basin) formed a separated group close to the anammox cluster with similarity of 82–90% to the described anaerobic ammonia-oxidizing species despite of the unsuitable environments for these bacteria in the wastewater treatment plant. However, the following batch experiment results indicated low level of anammox activity (anaerobic ammonia-oxidizing rate of 0.8 mg NH4+-N g−1 dry biomass day−1) existing in the anaerobic biomass of alcohol manufacturing wastewater treatment plant.  相似文献   

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The level of supercoiling in the chromosome can affect gene expression. To clarify the basis of supercoiling sensitivity, we analyzed the structural features of nucleotide sequences in the vicinity of promoters for the genes with expression enhanced and decreased in response to loss of chromosomal supercoiling in Escherichia coli. Fourier analysis of promoter sequences for supercoiling-sensitive genes reveals the tendency in selection of sequences with helical periodicities close to 10 nt for relaxation-induced genes and to 11 nt for relaxation-repressed genes. The helical periodicities in the subsets of promoters recognized by RNA polymerase with different sigma factors were also studied. A special procedure was developed for the study of correlations between the intensities of periodicities in promoter sequences and the expression levels of corresponding genes. Significant correlations of expression with the AT content and with AT periodicities about 10, 11, and 50 nt indicate their role in regulation of supercoiling-sensitive genes.  相似文献   

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《Process Biochemistry》2014,49(12):2313-2319
Acinetobacter calcoaceticus PUCM 1011 efficiently synthesized platinum nanoparticles (PtNP) of size 2–3 nm intracellularly when challenged with hexachloroplatinic acid. Salt concentration (1 mM), temperature (30 °C), pH (7) and incubation period (72 h) influenced the efficiency of monodisperse cuboidal PtNP synthesis. Resolution of ordered lattice fringes with “d” value of 0.23 nm corresponding to (1 1 1) plane and EDAX confirmed presence of metallic platinum. AFM, TEM and HR-TEM confirmed synthesis of PtNP and its effect on cell viability. Total cell protein profile for 120 h with an interval of 24 h after PtNP synthesis revealed prominent four protein bands (97, 66, 43 and 29 kDa) when compared to control. Combinations of three proteins initiated PtNP synthesis within 4 h in range of 1–4 nm and few in picometers under HR-TEM. This is the first report of PtNP synthesis employing whole cell and total cell protein of A. calcoaceticus.  相似文献   

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《Gene》1999,226(2):355-364
The Mpl ligand is a hematopoietic cytokine which exerts its effects through association with the c-Mpl receptor. It regulates the proliferation, polyploidization and maturation of platelet precursors, the megakaryocytes. Using a differential display polymerase chain reaction (PCR) approach, we have identified an mRNA, belonging to a family of nucleosome assembly proteins, whose expression is upregulated in response to Mpl ligand. Multiple size classes of this mRNA (1.7, 2.5 and 4.3 kb) are readily detected in rat primary bone marrow cells and hematopoietic tissues. The size classes are also expressed to different extents in cell lines of all hematopoietic lineages. We isolated the full-length cDNA encoding the rat megakaryocyte 1.7 kb mRNA, referred to as rNAP1. Bacterially expressed recombinant protein encoded by the 1.7 kb cDNA facilitates the formation of nucleosomes on relaxed circular DNA in vitro. Our data indicate that rNAPs, which may facilitate chromatin reorganization, are upregulated by Mpl ligand. It is possible that NAPs contribute to Mpl ligand's induced effects on hematopoietic cells.  相似文献   

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PurposeRadiolabeled oligomers complementary to the 16S rRNA in bacteria were investigated as bacterial infection imaging agents.Methods and resultsIdentical sequences with backbones phosphorodiamidate morpholino (MORF), peptide nucleic acid (PNA), and phosphorothioate DNA (PS-DNA) were 99mTc-labeled and evaluated for binding to bacterial RNA. MORF binding to RNA from Escherichia coli strains SM101 and K12 was 4- and 150-fold higher compared to PNA and PS-DNA, respectively. Subsequently MORF oligomer in fluorescence in situ hybridization showed a stronger signal with study MORF compared to control in fixed preparations of two E. coli strains and Klebsiella pneumoniae. Flow cytometry analysis showed study MORF accumulation to be 8- and 80-fold higher compared to the control in live K. pneumoniae and Staphylococcus aureus, respectively. Further, fluorescence microscopy showed increased accumulation of study MORF over control in live E. coli and K. pneumonia. Binding of 99mTc-study MORF to RNA from E. coli SM101 and K12 was 30.4 and 117.8 pmol, respectively, per 1010 cells. Mice with K. pneumoniae live or heat-killed (sterile inflammation) in one thigh at 90 min for both 99mTc-study MORF and control showed higher accumulation in target thighs than in blood and all other organs expect for kidneys and small intestine. Accumulation of 99mTc-study MORF was significantly higher (p = 0.009) than that of the control in the thigh with sterile inflammation.ConclusionA 99mTc-MORF oligomer complimentary to the bacterial 16S rRNA demonstrated binding to bacterial RNA in vitro with specific accumulation into live bacteria. Radiolabeled MORF oligomers antisense to the bacterial rRNA may be useful to image bacterial infection.  相似文献   

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Polyphenolic composition of alcohol-free red wine concentrates (AFRWC) was determined by LC–MS/MS. The concentration of salicylic acid in non-flavonoid class and malvidin in flavonoid class was the highest among all the polyphenols determined in AFRWC. In the in vitro model using HepG2 cells, AFRWC was found to be more effective for the reduction of total cholesterol than lovastatin. For the in vivo model, animals were provided with AFRWC at ~750 mg of total polyphenols/kg body weight per day by oral administration. The amount of AFRWC was established by extrapolation to be equivalent to 375 ml/day wine consumption, which is ~2–3 glasses of wine per day for a 60 kg human. Despite a high cholesterol diet, a significant reduction in both total cholesterol and LDL-cholesterol was observed when supplemented with AFRWC, but the increase of HDL-cholesterol was not observed. The expression level of mRNA of some hepatic genes participating in cholesterol biosynthesis, cholesterol esterification was found to be influenced by AFRWC supplementation, whereas reverse cholesterol transport involved with HDL-cholesterol was seldom affected showing discrepancy in the expression of associated genes.  相似文献   

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RNA is an extremely important target for the development of chemical probes of function or small molecule therapeutics. Aminoglycosides are the most well studied class of small molecules to target RNA. However, the RNA motifs outside of the bacterial rRNA A-site that are likely to be bound by these compounds in biological systems is largely unknown. If such information were known, it could allow for aminoglycosides to be exploited to target other RNAs and, in addition, could provide invaluable insights into potential bystander targets of these clinically used drugs. We utilized two-dimensional combinatorial screening (2DCS), a library-versus-library screening approach, to select the motifs displayed in a 3 × 3 nucleotide internal loop library and in a 6-nucleotide hairpin library that bind with high affinity and selectivity to six aminoglycoside derivatives. The selected RNA motifs were then analyzed using structure–activity relationships through sequencing (StARTS), a statistical approach that defines the privileged RNA motif space that binds a small molecule. StARTS allowed for the facile annotation of the selected RNA motif–aminoglycoside interactions in terms of affinity and selectivity. The interactions selected by 2DCS generally have nanomolar affinities, which is higher affinity than the binding of aminoglycosides to a mimic of their therapeutic target, the bacterial rRNA A-site.  相似文献   

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