Search results for "PRIMERS"
showing 10 items of 332 documents
Medicago species affect the community composition of arbuscular mycorrhizal fungi associated with roots
2007
National audience; The symbiosis between plants and arbuscular mycorrhizal fungi (AMF) is ancient and involves 80% of terrestrial plant families. The symbiotic association between AMF and plants was described to be non specific. However, AMF were reported to influence plant community diversity and productivity. On the other way, the effect of plant genotypes belonging to closely related species on AMF diversity has not been explored so far. The aim of this work was to assess the impact of four different Medicago species, M. laciniata, M. murex, M. polymorpha and M. truncatula cv. Jemalong J5, on the composition of AM fungal community, when cultivated in a silty-thin clay soil (Mas d’Imbert,…
Molecular characterization of cyclic and obligate parthenogens in the aphid Rhopalosiphum padi (L.)
1996
Holocyclic clones of the aphid Rhopalosiphum padi (L.) reproduce by cyclic parthenogenesis, whereas anholocyclic individuals are obligate parthenogens. Mitochondrial DNA (mtDNA) and random amplified polymorphic DNA markers in R . padi as well as plasmid DNA markers of its bacterial endosymbiont, Buchnera aphidicola , were examined to determine the extent of genetic divergence between clones with these differing breeding systems. These analyses revealed that cyclically parthenogenetic lineages possessed differing mtDNA and plasmid haplotypes than most obligately asexual clones. The extent of sequence divergence between these maternally inherited molecules suggests a relatively ancient origin…
Characterization of a novel selenium methyltransferase from freshwater bacteria showing strong similarities with the calicheamicin methyltransferase
2004
A novel group of Se-methyltransferases is presented. The genetic determinant, named mmtA, which revealed this group was isolated from selenite and selenate-resistant freshwater bacteria. E. coli expressing mmtA and grown with a Se supplement emitted dimethyl selenide (DMSe) and dimethyl diselenide (DMDSe). Phylogenetic analysis divided MmtA-like bacterial sequences into two clusters, one grouping MmtA with S- and O-methyltransferases, and one grouping UbiE C-methyltransferases. Se methylation by some of these MmtA phyletic neighbours was investigated.
Structure-function analysis of peroxisomal ATP-binding cassette transporters using chimeric dimers
2014
Background: Peroxisomal ABC transporters are predicted to function as homodimers in mammals. [br/] Results: ABCD1 interacts with ABCD2. Chimeric proteins mimicking full-length dimers represent novel tools for functional study. Artificial homodimers and heterodimers are functional. [br/] Conclusion: Interchangeability between ABCD1 and ABCD2 is confirmed, but PUFA transport depends on ABCD2. [br/] Significance: For the first time, heterodimers in mammals are proven to be functional.[br/] ABCD1 and ABCD2 are two closely related ATP-binding cassette half-transporters predicted to homodimerize and form peroxisomal importers for fatty acyl-CoAs. Available evidence has shown that ABCD1 and ABCD2 …
Failure to differentiate Cryptosporidium parvum from C. meleagridis based on PCR amplification of eight DNA sequences.
1998
ABSTRACT In order to determine the specificities of PCR-based assays used for detecting Cryptosporidium parvum DNA, eight pairs of previously described PCR primers targeting six distinct regions of the Cryptosporidium genome were evaluated for the detection of C. parvum , the agent of human cryptosporidiosis, and C. muris , C. baileyi , and C. meleagridis , three Cryptosporidium species that infect birds or mammals but are not considered to be human pathogens. The four Cryptosporidium species were divided into two groups: C. parvum and C. meleagridis , which gave the same-sized fragments with all the reactions, and C. muris and C. baileyi , which gave positive results with primer pairs targ…
Stearoyl-CoA desaturase 1 coding sequences abd antisense RNA affect lipid secretion in transfected chicken LMH hepatoma cells
2000
Hepatic stearoyl CoA desaturase (SCD) activity in chickens from a fat line is higher than that of chickens from a lean line and correlates with plasma triacylglycerol concentrations. Furthermore, in these lines, the hepatic SCD1 mRNA level is positively correlated with the adipose tissue weight. To analyze the contribution of the SCD1 gene in the regulation of adiposity in the early stages of triacylglycerol secretion, SCD1 coding sequence and antisense RNA expression vectors were transfected in LMH cells. After selection, these cells were analyzed with regard to SCD1 expression and lipid secretion. The amounts of secreted triacylglycerols and phospholipids were shown to be higher in LMH ce…
Insecticidal Activity of Strains of Bacillus thuringiensis on Larvae and Adults of Bactrocera oleae Gmelin (Dipt. Tephritidae)
1999
The olive fly, Bactrocera oleae, is the key pest on olives in the Mediterranean area. The pest can destroy, in some cases, up to 70% of the olive production. Its control relies mainly on chemical treatments, sometimes applied by aircraft over vast areas, with their subsequent ecological and toxicological side effects. Bacillus thuringiensis is a spore-forming soil bacterium which produces a protein crystal toxic to some insects, including the orders of Lepidoptera, Diptera, and Coleoptera and other invertebrates. The aim of this study was to search for isolates toxic to B. oleae. Several hundred B. thuringiensis isolates were obtained from olive groves and olive presses in different areas o…
Identification ofCandida albicansclinical isolates by PCR amplification of anEFB1gene fragment containing an intron-interrupted open reading frame
2000
The use of a single pair of primers, deduced from the intron and exon nucleotide sequences of the Candida albicans EFB1 gene, in polymerase chain reaction (PCR) assays performed with whole cells of both laboratory strains and clinical isolates of Candida species, resulted in the species-specific amplification of a 785 bp DNA fragment in C. albicans strains. Clinical C. albicans isolates were tested, and 85 out of 86 generated the expected PCR-amplified product; other Candida species, both laboratory strains and clinical isolates, as well as laboratory strains belonging to other fungal genera, including medically relevant taxa, failed to amplify any DNA fragment. In addition, unusual C. albi…
Effects of anti-miR-182 on TSP-1 expression in human colon cancer cells: there is a sense in antisense?
2013
Abstract: Objective: miRNAs are attractive molecules for cancer treatment, including colon rectal cancer (CRC). We investigate on the molecular mechanism by which miR-182 could regulate thrombospondin-1 (TSP-1) expression, a protein down-regulated in CRC and inversely correlated with tumor vascularity and metastasis. Background: MicroRNAs are small non-coding RNAs that regulate the expression of different genes, involved in cancer progression, angiogenesis and metastasis. miR-182, over-expressed in colorectal cancer (CRC), has like predictive target thrombospondin-1 (TSP-1), a protein inversely correlated with tumor vascularity and metastasis that results downregulated in different types of…
Validation and application of a PCR primer set to quantify fungal communities in the soil environment by real-time quantitative PCR
2011
Fungi constitute an important group in soil biological diversity and functioning. However, characterization and knowledge of fungal communities is hampered because few primer sets are available to quantify fungal abundance by real-time quantitative PCR (real-time Q-PCR). The aim in this study was to quantify fungal abundance in soils by incorporating, into a real-time Q-PCR using the SYBRGreen (R) method, a primer set already used to study the genetic structure of soil fungal communities. To satisfy the real-time Q-PCR requirements to enhance the accuracy and reproducibility of the detection technique, this study focused on the 18S rRNA gene conserved regions. These regions are little affec…