170 research outputs found
4Pipe4-A 454 data analysis pipeline for SNP detection in datasets with no reference sequence or strain information
This work was fully supported by projects SOBREIRO/0036/2009 (under the framework of the Cork Oak ESTs Consortium), PTDC/BIA-BEC/098783/2008 and PTDC/AGR-GPL/119943/2010 from Fundação para a CiĂȘncia e Tecnologia (FCT) â Portugal. F. Pina-Martins was funded by FCT grant SFRH/BD/51411/2011, under the PhD program âBiology and Ecology of Global Changesâ, Univ. Aveiro & Univ. Lisbon, Portugal. D. Batista was funded by FCT grant SFRH/BPD/104629/2014
Ki-67 is strongly prognostic in synovial sarcoma: analysis based on 86 patients from the Scandinavian Sarcoma Group Register
Gene and genon concept: coding versus regulation: A conceptual and information-theoretic analysis of genetic storage and expression in the light of modern molecular biology
We analyse here the definition of the gene in order to distinguish, on the basis of modern insight in molecular biology, what the gene is coding for, namely a specific polypeptide, and how its expression is realized and controlled. Before the coding role of the DNA was discovered, a gene was identified with a specific phenotypic trait, from Mendel through Morgan up to Benzer. Subsequently, however, molecular biologists ventured to define a gene at the level of the DNA sequence in terms of coding. As is becoming ever more evident, the relations between information stored at DNA level and functional products are very intricate, and the regulatory aspects are as important and essential as the information coding for products. This approach led, thus, to a conceptual hybrid that confused coding, regulation and functional aspects. In this essay, we develop a definition of the gene that once again starts from the functional aspect. A cellular function can be represented by a polypeptide or an RNA. In the case of the polypeptide, its biochemical identity is determined by the mRNA prior to translation, and that is where we locate the gene. The steps from specific, but possibly separated sequence fragments at DNA level to that final mRNA then can be analysed in terms of regulation. For that purpose, we coin the new term âgenonâ. In that manner, we can clearly separate product and regulative information while keeping the fundamental relation between coding and function without the need to introduce a conceptual hybrid. In mRNA, the program regulating the expression of a gene is superimposed onto and added to the coding sequence in cis - we call it the genon. The complementary external control of a given mRNA by trans-acting factors is incorporated in its transgenon. A consequence of this definition is that, in eukaryotes, the gene is, in most cases, not yet present at DNA level. Rather, it is assembled by RNA processing, including differential splicing, from various pieces, as steered by the genon. It emerges finally as an uninterrupted nucleic acid sequence at mRNA level just prior to translation, in faithful correspondence with the amino acid sequence to be produced as a polypeptide. After translation, the genon has fulfilled its role and expires. The distinction between the protein coding information as materialised in the final polypeptide and the processing information represented by the genon allows us to set up a new information theoretic scheme. The standard sequence information determined by the genetic code expresses the relation between coding sequence and product. Backward analysis asks from which coding region in the DNA a given polypeptide originates. The (more interesting) forward analysis asks in how many polypeptides of how many different types a given DNA segment is expressed. This concerns the control of the expression process for which we have introduced the genon concept. Thus, the information theoretic analysis can capture the complementary aspects of coding and regulation, of gene and genon
Evidence of Latitudinal Migration in Tri-colored Bats, Perimyotis subflavus
Background: Annual movements of tri-colored bats (Perimyotis subflavus) are poorly understood. While this species has been considered a regional migrant, some evidence suggests that it may undertake annual latitudinal migrations, similar to other long distance North American migratory bat species. Methodology/Principal Findings: We investigated migration in P. subflavus by conducting stable hydrogen isotope analyses of 184 museum specimen fur samples and comparing these results (dDfur) to published interpolated dD values of collection site growing season precipitation (dDprecip). Results suggest that the male molt period occurred between June 23 and October 16 and 33 % of males collected during the presumed non-molt period were south of their location of fur growth. For the same time period, 16 % of females were south of their location of fur growth and in general, had not travelled as far as migratory males. There were strong correlations between dDfur from the presumed molt period and both growing season dD precip (males â r 2 = 0.86; p,0.01; females â r 2 = 0.75; p,0.01), and latitude of collection (males â r 2 = 0.85; p,0.01; females â r 2 = 0.73; p,0.01). Most migrants were collected at the northern (.40uN; males and females) and southern (,35uN; males only) extents of the species â range. Conclusions/Significance: These results indicate a different pattern of migration for this species than previously documented, suggesting that some P. subflavus engage in annual latitudinal migrations and that migratory tendency varie
Sequence comparison of prefrontal cortical brain transcriptome from a tame and an aggressive silver fox (Vulpes vulpes)
<p>Abstract</p> <p>Background</p> <p>Two strains of the silver fox (<it>Vulpes vulpes</it>), with markedly different behavioral phenotypes, have been developed by long-term selection for behavior. Foxes from the tame strain exhibit friendly behavior towards humans, paralleling the sociability of canine puppies, whereas foxes from the aggressive strain are defensive and exhibit aggression to humans. To understand the genetic differences underlying these behavioral phenotypes fox-specific genomic resources are needed.</p> <p>Results</p> <p>cDNA from mRNA from pre-frontal cortex of a tame and an aggressive fox was sequenced using the Roche 454 FLX Titanium platform (> 2.5 million reads & 0.9 Gbase of tame fox sequence; >3.3 million reads & 1.2 Gbase of aggressive fox sequence). Over 80% of the fox reads were assembled into contigs. Mapping fox reads against the fox transcriptome assembly and the dog genome identified over 30,000 high confidence fox-specific SNPs. Fox transcripts for approximately 14,000 genes were identified using SwissProt and the dog RefSeq databases. An at least 2-fold expression difference between the two samples (p < 0.05) was observed for 335 genes, fewer than 3% of the total number of genes identified in the fox transcriptome.</p> <p>Conclusions</p> <p>Transcriptome sequencing significantly expanded genomic resources available for the fox, a species without a sequenced genome. In a very cost efficient manner this yielded a large number of fox-specific SNP markers for genetic studies and provided significant insights into the gene expression profile of the fox pre-frontal cortex; expression differences between the two fox samples; and a catalogue of potentially important gene-specific sequence variants. This result demonstrates the utility of this approach for developing genomic resources in species with limited genomic information.</p
Meta-analysis of the relation between European and American smokeless tobacco and oral cancer
<p>Abstract</p> <p>Background</p> <p>Smokeless tobacco is often referred to as a major contributor to oral cancer. In some regions, especially Southeast Asia, the risk is difficult to quantify due to the variety of products, compositions (including non-tobacco ingredients) and usage practices involved. In Western populations, the evidence of an increased risk in smokeless tobacco users seems unclear, previous reviews having reached somewhat differing conclusions. We report a detailed quantitative review of the evidence in American and European smokeless tobacco users, and compare our findings with previous reviews and meta-analyses.</p> <p>Methods</p> <p>Following literature review a meta-analysis was conducted of 32 epidemiological studies published between 1920 and 2005 including tests for homogeneity and publication bias.</p> <p>Results</p> <p>Based on 38 heterogeneous study-specific estimates of the odds ratio or relative risk for smokeless tobacco use, the random-effects estimate was 1.87 (95% confidence interval 1.40â2.48). The increase was mainly evident in studies conducted before 1980. No increase was seen in studies in Scandinavia. Restricting attention to the seven estimates adjusted for smoking and alcohol eliminated both heterogeneity and excess risk (1.02; 0.82â1.28). Estimates also varied by sex (higher in females) and by study design (higher in case-control studies with hospital controls) but more clearly in studies where estimates were unadjusted, even for age. The pattern of estimates suggests some publication bias. Based on limited data specific to never smokers, the random-effects estimate was 1.94 (0.88â4.28), the eight individual estimates being heterogeneous and based on few exposed cases.</p> <p>Conclusion</p> <p>Smokeless tobacco, as used in America or Europe, carries at most a minor increased risk of oral cancer. However, elevated risks in specific populations or from specific products cannot definitely be excluded.</p
Experimental determination of the complete spin structure for pÂŻpâ ÎÂŻÎ at p{pÂŻ}= 1.637 GeV/c
The reaction p.p â ^^ â .pÏ+pÏâ has been measured with high statistics at a beam momentum of pp. = 1.637 GeV/c. The use of a transversely polarized frozen-spin target combined with the self-analyzing property of ^/^ decay allows access to unprecedented information on the spin structure of the interaction. The most general spin-scattering matrix can be written in terms of 11 real parameters for each bin of scattering angle; each of these parameters is determined with reasonable precision. From these results, all conceivable spin correlations are determined with inherent self-consistency. Good agreement is found with the few previously existing measurements of spin observables in p.p â ^^ near this energy. Existing theoretical models do not give good predictions for those spin observables that had not been previously measured
COLEC10 is mutated in 3MC patients and regulates early craniofacial development
3MC syndrome is an autosomal recessive heterogeneous disorder with features linked to developmental abnormalities. The main features include facial dysmorphism, craniosynostosis and cleft lip/palate; skeletal structures derived from cranial neural crest cells (cNCC). We previously reported that lectin complement pathway genes COLEC11 and MASP1/3 are mutated in 3MC syndrome patients. Here we define a new gene, COLEC10, also mutated in 3MC families and present novel mutations in COLEC11 and MASP1/3 genes in a further five families. The protein products of COLEC11 and COLEC10, CL-K1 and CL-L1 respectively, form heteromeric complexes. We show COLEC10 is expressed in the base membrane of the palate during murine embryo development. We demonstrate how mutations in COLEC10 (c.25C>T; p.Arg9Ter, c.226delA; p.Gly77Glufs*66 and c.528C>G p.Cys176Trp) impair the expression and/or secretion of CL-L1 highlighting their pathogenicity. Together, these findings provide further evidence linking the lectin complement pathway and complement factors COLEC11 and COLEC10 to morphogenesis of craniofacial structures and 3MC etiology.New life Fundation for Disabled Childre
Expression of Metallothioneins in Cutaneous Squamous Cell Carcinoma and Actinic Keratosis
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