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31.
Molecular characterization of the equine AEG1 locus   总被引:2,自引:0,他引:2  
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European ash (Fraxinus excelsior) is currently battling an onslaught of ash dieback, a disease emerging in the greater part of its native area, brought about by the introduction of the ascomycete Hymenoscyphus fraxineus (= Hymenoscyphus pseudoalbidus). The closely-related fungus Hymenoscyphus albidus, which is indigenous to Europe, is non-pathogenic when in contact with F. excelsior, but could pose a potential risk to exotic Fraxinus species. The North American green ash (Fraxinus pennsylvanica) is planted widely throughout Europe and regenerates naturally within this environment but little is known about the susceptibility of this species to ash dieback. We performed wound inoculations with both fungi (nine strains of H. fraxineus and three strains of H. albidus) on rachises and stems of F. excelsior and F. pennsylvanica under field conditions in Southern Poland. Necrosis formation was evaluated after two months on the rachises and after 12 months on the stems. After inoculation of H. albidus, only small lesions (of up to 1.3 cm in length) developed on the F. excelsior and F. pennsylvanica rachises, but with no significant distinction from the controls. Hymenoscyphus albidus did not cause necrotic lesions on the stems of either Fraxinus species. In contrast, H. fraxineus induced necroses on all inoculated rachises of both ash species with mean lengths of 8.4 cm (F. excelsior) and 1.9 cm (F. pennsylvanica). Necroses also developed on all of the inoculated F. excelsior stems (mean length 18.0 cm), whereas on F. pennsylvanica such lesions only occurred on about 5% of the stems (mean length 1.9 cm). The differences between strains were negligible. No necroses were observed on the control plants. Reisolations of H. albidus were only successful in around 8–11% of the cases, while H. fraxineus was reisolated from 50–70% of the inoculated organs showing necrotic lesions. None of the Hymenoscyphus species were isolated from the control plants. Our data confirm H. fraxineus’ high virulence with regards to F. excelsior and demonstrate a low virulence in relation to F. pennsylvanica under field conditions in Poland. Hymenoscyphus albidus did not express any perceivable pathogenicity on both host species.  相似文献   
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Different cytokines are secreted in response to specific microbial molecules referred to as pathogen associated molecular patterns (PAMPs). Interleukin 6 (IL6) and interleukin 10 (IL10), both secreted by macrophages and lymphocytes, play a central role in the immunological response. In this work we obtained the genomic structure and complete DNA sequence of the porcine IL6 and IL10 genes and identified polymorphisms in the genomic sequences of these genes on a panel of ten different pig breeds. Comparative intra- and interbreed sequence analysis revealed a total of eight polymorphisms in the porcine IL6 gene and 21 in the porcine IL10 gene, which include single nucleotide polymorphisms (SNPs) and insertion deletion polymorphisms (indels). Additionally, the chromosomal localization of the IL10 gene was determined by FISH and RH mapping.  相似文献   
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Neanderthal diets are reported to be based mainly on the consumption of large and medium sized herbivores, while the exploitation of other food types including plants has also been demonstrated. Though some studies conclude that early Homo sapiens were active hunters, the analyses of faunal assemblages, stone tool technologies and stable isotopic studies indicate that they exploited broader dietary resources than Neanderthals. Whereas previous studies assume taxon-specific dietary specializations, we suggest here that the diet of both Neanderthals and early Homo sapiens is determined by ecological conditions. We analyzed molar wear patterns using occlusal fingerprint analysis derived from optical 3D topometry. Molar macrowear accumulates during the lifespan of an individual and thus reflects diet over long periods. Neanderthal and early Homo sapiens maxillary molar macrowear indicates strong eco-geographic dietary variation independent of taxonomic affinities. Based on comparisons with modern hunter-gatherer populations with known diets, Neanderthals as well as early Homo sapiens show high dietary variability in Mediterranean evergreen habitats but a more restricted diet in upper latitude steppe/coniferous forest environments, suggesting a significant consumption of high protein meat resources.  相似文献   
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Polledness is a high impact trait in modern milk and beef production to meet the demands of animal welfare and work safety. Previous studies have mapped the polled-locus to the proximal region of the bovine chromosome 1 (BTA1) and narrowed it down to approximately 1 Mb. Sequencing of the positional candidate genes within the 1 Mb polled region and whole genome sequencing of Holsteins revealed a single nucleotide polymorphism (SNP) AC000158: g.1390292G>A within intron 3 of the interferon gamma receptor 2 gene (IFNGR2) in perfect co-segregation with polledness in Holsteins. This complete association was validated in 443 animals of the same breed. This SNP allows reliable genotyping of horned, heterozygous and homozygous polled Holsteins, even in animals that could not be resolved using the previously published haplotype for Holstein.  相似文献   
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Dilated cardiomyopathy (DCM) is a common disease in humans and dogs. Large-breed dogs and especially Irish wolfhounds belong to the frequently affected breeds. Male Irish wolfhounds show a significantly higher prevalence of DCM than females. Therefore, we evaluated X chromosome markers for linkage with DCM as well as a human candidate gene on the X chromosome. A set of X chromosomal microsatellites was genotyped in Irish wolfhound families segregating for DCM. In addition, exon and intron sequences of the tafazzin (TAZ) gene were assayed for polymorphisms segregating in these families. Statistical analysis of the microsatellite markers did not reveal linkage to DCM. Furthermore, all Irish wolfhounds included in this study were monomorphic for TAZ, and only 8 sequence differences to the Dog Genome Assembly 2.1 could be found. The results indicate that due to the lack of mutations, TAZ is unlikely to cause DCM in Irish wolfhounds.  相似文献   
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