Hydrogen bonding of nitroxide spin labels in membrane proteins

On the basis of experiments at 275 GHz, we reconsider the dependence of the continuous-wave EPR spectra of nitroxide spin-labeled protein sites in sensory- and bacteriorhodopsin on the micro-environment. The high magnetic field provides the resolution necessary to disentangle the effects of hydrogen bonding and polarity. In the gxx region of the 275 GHz EPR spectrum, bands are resolved that derive from spin-label populations carrying no, one or two hydrogen bonds. The gxx value of each population varies hardly from site to site, significantly less than deduced previously from studies at lower microwave frequencies. The fractions of the populations vary strongly, which provides a consistent description of the variation of the average gxx and the average nitrogen-hyperfine interaction Azz from site to site. These variations reflect the difference in the proticity of the micro-environment, and differences in polarity contribute marginally. Concomitant W-band ELDOR- detected NMR experiments on the corresponding nitroxide in perdeuterated water resolve population-specific nitrogen-hyperfine bands, which underlies the interpretation for the proteins

Integration of GWAS, CNV and sele ction signature reveals candidate genes for abdominal fat regulation in chickens.

Abstract: Carcass fat content is an economically important trait in commercial chickens. The use of genome-wide high density SNPs may improve the power and resolution to identify QTLs, putative candidate genes and copy number variations (CNVs), for selection programs. The main goal of this study was to identify genomic windows and putative candidate genes for carcass fat content. We checked the overlap of QTL with regions demonstrating signatures of selection and inherited CNVs identified in the same population. A total of 497 42 day-old chickens from the EMBRAPA F2 Chicken Resource Population developed for QTL studies were genotyped with the 600K SNP genotyping array (Affymetrix®), and phenotyped for carcass fat content weight (CFCW) and carcass fat content on a dry matter basis (CFCDM). After quality control, a total of 480 samples and 371,557 SNPs annotated in autosomal chromosomes (GGA1-28) based on Gallus_gallus-5.0 (NCBI) were kept for further analysis. GWAS analyses were performed with GenSel software using BayesB method (π=0.9988) to identify genomic windows associated with CFCW or CFC%. We identified 15 genomic windows associated with CFC% on GGA1, 7, 15, 20 and 28, and from those, we identified two adjacent windows on GGA7 considered as the same QTL explaining 1.31 and 2.18% of the genetic variance for CFCW and CFC%, respectively. This QTL overlapped with one regions previsiouly know to regulate abdominal fat in chickens and the QTL region encompassed two putative candidate genes overlapping with signatures of selection and inherited CNVs. Our findings are helpful to better understand the genetic regulation of fatness in chickens. Resumo: O teor de gordura na carcaça é uma característica economicamente importante em frangos comerciais. O uso de SNPs de alta densidade em todo o genoma pode melhorar o poder e a resolução para identificar QTLs, genes candidatos putativos e variações no número de cópias (CNVs), para programas de seleção. O principal objetivo deste estudo foi identificar janelas genômicas e possíveis genes candidatos para o conteúdo de gordura na carcaça. Verificamos a sobreposição de QTL com regiões demonstrando assinaturas de seleção e CNVs herdadas identificadas na mesma população. Um total de 497 galinhas com 42 dias de idade da EMBRAPA F2 Chicken Resource Population desenvolvidas para estudos QTL foram genotipadas com o arranjo de genótipos SNP 600K (Affymetrix®) e fenotipadas para peso de gordura na carcaça (CFCW) e teor de gordura na carcaça seca. matéria básica (CFCDM). Após o controle de qualidade, um total de 480 amostras e 371.557 SNPs anotados em cromossomos autossômicos (GGA1-28) baseados em Gallus_gallus-5.0 (NCBI) foram mantidos para análise posterior. As análises de GWAS foram realizadas com o software GenSel usando o método de BayesB (π = 0,9988) para identificar janelas genômicas associadas ao CFCW ou CFC%. Foram identificadas 15 janelas genômicas associadas a% CFC em GGA1, 7, 15, 20 e 28 e, a partir delas, identificamos duas janelas adjacentes em GGA7 consideradas como os mesmos QTLs explicando 1,31 e 2,18% da variância genética para CFCW e CFC% , respectivamente. Este QTL se sobrepunha a uma das regiões previsamente conhecidas para regular a gordura abdominal em frangos e a região QTL englobava dois supostos genes candidatos que se sobrepunham com assinaturas de seleção e CNVs herdadas. Nossas descobertas são úteis para entender melhor a regulação genética da gordura em frangos

Strong signatures of selection in the domestic pig genome

Domestication of wild boar (Sus scrofa) and subsequent selection have resulted in dramatic phenotypic changes in domestic pigs for a number of traits, including behavior, body composition, reproduction, and coat color. Here we have used whole-genome resequencing to reveal some of the loci that underlie phenotypic evolution in European domestic pigs. Selective sweep analyses revealed strong signatures of selection at three loci harboring quantitative trait loci that explain a considerable part of one of the most characteristic morphological changes in the domestic pig—the elongation of the back and an increased number of vertebrae. The three loci were associated with the NR6A1, PLAG1, and LCORL genes. The latter two have repeatedly been associated with loci controlling stature in other domestic animals and in humans. Most European domestic pigs are homozygous for the same haplotype at these three loci. We found an excess of derived nonsynonymous substitutions in domestic pigs, most likely reflecting both positive selection and relaxed purifying selection after domestication. Our analysis of structural variation revealed four duplications at the KIT locus that were exclusively present in white or white-spotted pigs, carrying the Dominant white, Patch, or Belt alleles. This discovery illustrates how structural changes have contributed to rapid phenotypic evolution in domestic animals and how alleles in domestic animals may evolve by the accumulation of multiple causative mutations as a response to strong directional selection

Task Force 7: Training Guidelines for Research in Pediatric Cardiology

Aim of the study. The aim of the study was to analyze the benefit from adjuvant radiotherapy in patients with vulvar cancer and a single positive node without extra capsular spread. Materials and methods. The Study population comprised data of 75 patients with vulvar cancer and one lymph node metastasis. The patients were treated in three different university centers in Amsterdam, Groningen and Rotterdam between 1984 and 2005. Results. Out of 75 patients, 31 (41%) were treated with adjuvant radiotherapy. Both disease-free survival (DFS) and disease-specific survival (DSS) were comparable between the groups who did and who did not receive adjuvant radiotherapy (HR 0.98, 95% CI 0.45-2.14, p=0.97 and HR = 1.02, 95% CI 0.42-2.47, p = 0.96). Conclusion. We could not demonstrate any beneficial effect of adjuvant radiotherapy in the group Of patients with one intra capsular metastasis. (C) 2009 Elsevier Inc. All rights reserved

A high-density SNP chip for genotyping great tit (Parus major) populations and its application to studying the genetic architecture of exploration behaviour

High‐density SNP microarrays (“SNP chips”) are a rapid, accurate and efficient method for genotyping several hundred thousand polymorphisms in large numbers of individuals. While SNP chips are routinely used in human genetics and in animal and plant breeding, they are less widely used in evolutionary and ecological research. In this article, we describe the development and application of a high‐density Affymetrix Axiom chip with around 500,000 SNP s, designed to perform genomics studies of great tit (Parus major ) populations. We demonstrate that the per‐SNP genotype error rate is well below 1% and that the chip can also be used to identify structural or copy number variation. The chip is used to explore the genetic architecture of exploration behaviour (EB ), a personality trait that has been widely studied in great tits and other species. No SNP s reached genomewide significance, including at DRD 4 , a candidate gene. However, EB is heritable and appears to have a polygenic architecture. Researchers developing similar SNP chips may note: (i) SNP s previously typed on alternative platforms are more likely to be converted to working assays; (ii) detecting SNP s by more than one pipeline, and in independent data sets, ensures a high proportion of working assays; (iii) allele frequency ascertainment bias is minimized by performing SNP discovery in individuals from multiple populations; and (iv) samples with the lowest call rates tend to also have the greatest genotyping error rates

Methods for interpreting lists of affected genes obstained in a DNA microarray experiment

Background - The aim of this paper was to describe and compare the methods used and the results obtained by the participants in a joint EADGENE (European Animal Disease Genomic Network of Excellence) and SABRE (Cutting Edge Genomics for Sustainable Animal Breeding) workshop focusing on post analysis of microarray data. The participating groups were provided with identical lists of microarray probes, including test statistics for three different contrasts, and the normalised log-ratios for each array, to be used as the starting point for interpreting the affected probes. The data originated from a microarray experiment conducted to study the host reactions in broilers occurring shortly after a secondary challenge with either a homologous or heterologous species of Eimeria. Results - Several conceptually different analytical approaches, using both commercial and public available software, were applied by the participating groups. The following tools were used: Ingenuity Pathway Analysis, MAPPFinder, LIMMA, GOstats, GOEAST, GOTM, Globaltest, TopGO, ArrayUnlock, Pathway Studio, GIST and AnnotationDbi. The main focus of the approaches was to utilise the relation between probes/genes and their gene ontology and pathways to interpret the affected probes/genes. The lack of a well-annotated chicken genome did though limit the possibilities to fully explore the tools. The main results from these analyses showed that the biological interpretation is highly dependent on the statistical method used but that some common biological conclusions could be reached. Conclusion - It is highly recommended to test different analytical methods on the same data set and compare the results to obtain a reliable biological interpretation of the affected genes in a DNA microarray experimen

The de novo FAIRification process of a registry for vascular anomalies

Contains fulltext : 237199.pdf (Publisher’s version ) (Open Access

Comparison of linkage disequilibrium and haplotype diversity on macro- and microchromosomes in chicken

<p>Abstract</p> <p>Background</p> <p>The chicken (<it>Gallus gallus</it>), like most avian species, has a very distinct karyotype consisting of many micro- and a few macrochromosomes. While it is known that recombination frequencies are much higher for micro- as compared to macrochromosomes, there is limited information on differences in linkage disequilibrium (LD) and haplotype diversity between these two classes of chromosomes. In this study, LD and haplotype diversity were systematically characterized in 371 birds from eight chicken populations (commercial lines, fancy breeds, and red jungle fowl) across macro- and microchromosomes. To this end we sampled four regions of ~1 cM each on macrochromosomes (GGA1 and GGA2), and four 1.5 -2 cM regions on microchromosomes (GGA26 and GGA27) at a high density of 1 SNP every 2 kb (total of 889 SNPs).</p> <p>Results</p> <p>At a similar physical distance, LD, haplotype homozygosity, haploblock structure, and haplotype sharing were all lower for the micro- as compared to the macrochromosomes. These differences were consistent across populations. Heterozygosity, genetic differentiation, and derived allele frequencies were also higher for the microchromosomes. Differences in LD, haplotype variation, and haplotype sharing between populations were largely in line with known demographic history of the commercial chicken. Despite very low levels of LD, as measured by r²for most populations, some haploblock structure was observed, particularly in the macrochromosomes, but the haploblock sizes were typically less than 10 kb.</p> <p>Conclusion</p> <p>Differences in LD between micro- and macrochromosomes were almost completely explained by differences in recombination rate. Differences in haplotype diversity and haplotype sharing between micro- and macrochromosomes were explained by differences in recombination rate and genotype variation. Haploblock structure was consistent with demography of the chicken populations, and differences in recombination rates between micro- and macrochromosomes. The limited haploblock structure and LD suggests that future whole-genome marker assays will need 100+K SNPs to exploit haplotype information. Interpretation and transferability of genetic parameters will need to take into account the size of chromosomes in chicken, and, since most birds have microchromosomes, in other avian species as well.</p