Search results for "Chain reaction"
showing 10 items of 1862 documents
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 …
Ecological role of mycotoxins produced by Fusarium graminearum : consequences of the presence of deoxynivalenol (DON) in crop residues on the soil mi…
2012
Fusarium graminearum is a plant pathogenic fungus, causing devastating disease “Fusarium head blight” (FHB) in cereals including wheat and maize. It also contaminates the grains with mycotoxins including deoxynivalenol (DON) which are toxic to human and animals. This disease has resulted in the serious losses in grain yield and quality. We established through a first bibliographic review that during off season fungus survives saprophytically on the crop residues (ecological habitat) and serves as primary inoculum for the next season crop. However, we noticed also that the literature was poor about the role mycotoxins could play in the establishment of F. graminearum in such a habitat. The m…
High-throughput sequencing of amplicons for monitoring yeast biodiversity in must and during alcoholic fermentation
2014
Abstract We compared pyrosequencing technology with the PCR-ITS-RFLP analysis of yeast isolates and denaturing gradient gel electrophoresis (DGGE). These methods gave divergent findings for the yeast population. DGGE was unsuitable for the quantification of biodiversity and its use for species detection was limited by the initial abundance of each species. The isolates identified by PCR-ITS-RFLP were not fully representative of the true population. For population dynamics, high-throughput sequencing technology yielded results differing in some respects from those obtained with other approaches. This study demonstrates that 454 pyrosequencing of amplicons is more relevant than other methods …
Impact of a new bio-pesticide produced by Paenibacillus sp. strain B2 on the genetic structure and density of soil bacterial communities
2007
The effect of paenimyxin, a new biopesticide produced by Paenibacillus sp. strain B2, on the density of soil bacterial communities was assessed by colony counting and by 16S rDNA and nirK quantitative polymerase chain reaction (PCR). Paenimyxin had a negative effect on the bacterial colony-forming unit (CFU) number, which was significantly reduced 2 and 4 days after treatment. The effect of paenimyxin on cultivatable bacteria was negligible 7 days after treatment. Approximately 107 16S rDNA sequences per gram of soil (dry weight) were detected by quantitative PCR in all samples. Paenimyxin did not affect the quantification of 16S rDNA or of the denitrifying bacterial community. In addition,…
The Largest Subunit of RNA Polymerase II as a New Marker Gene to Study Assemblages of Arbuscular Mycorrhizal Fungi in the Field
2014
Due to the potential of arbuscular mycorrhizal fungi (AMF, Glomeromycota) to improve plant growth and soil quality, the influence of agricultural practice on their diversity continues to be an important research question. Up to now studies of community diversity in AMF have exclusively been based on nuclear ribosomal gene regions, which in AMF show high intra-organism polymorphism, seriously complicating interpretation of these data. We designed specific PCR primers for 454 sequencing of a region of the largest subunit of RNA polymerase II gene, and established a new reference dataset comprising all major AMF lineages. This gene is known to be monomorphic within fungal isolates but shows an…
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…
Molecular mechanisms of primary and secondary mucosal immunity using avian infectious bronchitis virus as a model system
2007
Although mucosal immune responses are critical for protection of hosts from clinical illness and even mortality caused by mucosal pathogens, the molecular mechanism of mucosal immunity, which is independent of systemic immunity, remains elusive. To explore the mechanistic basis of mucosal protective immunity, gene transcriptional profiling in mucosal tissues was evaluated after the primary and secondary immunization of animals with an attenuated avian infectious bronchitis virus (IBV), a prototype of Coronavirus and a well-characterized mucosal pathogen. Results showed that a number of innate immune factors including toll-like receptors (TLRs), retinoic-acid-inducible gene-1 (RIG-1), type I…
PCR survey ofXenoturbella bockiHox genes
2007
Xenoturbella bocki has recently been identified as one of the most basal deuterostomes, although an even more basal phylogenetic position cannot be ruled out. Here we report on a polymerase chain reaction survey of partial Hox homeobox sequences of X. bocki. Surprisingly, we did not find evidence for more than five Hox genes, one clear labial/PG1 ortholog, one posterior gene most similar to the PG9/10 genes of Ambulacraria, and three central group genes whose precise assignment to a specific paralog group remains open. We furthermore report on a re-evaluation of the available published evidence of Hox genes in other basal deuterostomes.
An improved high yield method to obtain microsatellite genotypes from red deer antlers up to 200 years old.
2013
Analysis of DNA from older samples, such as museum specimen, is a promising approach to studying genetics of populations and ecological processes across several generations. Here, we present a method for extracting high quality nuclear DNA for microsatellite analysis from antlers of red deer (Cervus elaphus). The genotyping of individuals was based on nine microsatellite loci. Because the amount of DNA found in antlers was high, we could reduce the amount of sample and chemicals used and shorten the decalcification time in comparison to other methods. Using these methods, we obtained genotypes from antlers up to 200 years old.
The Sea Urchin sns Insulator Blocks CMV Enhancer following Integration in Human Cells
2001
Insulators are a new class of genetic elements that attenuate enhancer function directionally. Previously, we characterized in sea urchin a 265-bp-long insulator, termed sns. To test insulator activity following stable integration in human cells, we placed sns between the CMV enhancer and a tk promoter up-stream of a GFP transgene of plasmid or retroviral vectors. In contrast to controls, cells transfected or transduced with insulated constructs displayed a barely detectable fluorescence. Southern blot and PCR ruled out vector rearrangement following integration into host DNA; RNase protection confirmed the enhancer blocking activity. Finally, we demonstrate that two cis-acting sequences, p…