Different Evolutionary Histories of the Two Classical Class I Genes BF1 and BF2 Illustrate Drift and Selection within the Stable MHC Haplotypes of Chickens
| العنوان: | Different Evolutionary Histories of the Two Classical Class I Genes BF1 and BF2 Illustrate Drift and Selection within the Stable MHC Haplotypes of Chickens |
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| المؤلفون: | Andy van Hateren, James C. Kaufman, Patricia Riegert, Timothy J. Powell, Michael V. Wiles, Ken Baker, Sarah Milne, Iain Shaw, Denise A. Marston, Stephan Beck |
| المصدر: | The Journal of Immunology. 178:5744-5752 |
| بيانات النشر: | The American Association of Immunologists, 2007. |
| سنة النشر: | 2007 |
| مصطلحات موضوعية: | Pseudogene, Molecular Sequence Data, Immunology, Gene Expression, Genes, MHC Class I, Locus (genetics), Major histocompatibility complex, Evolution, Molecular, Animals, Immunology and Allergy, Promoter Regions, Genetic, Enhancer, Gene, Phylogeny, Genomic organization, Genetics, Base Sequence, biology, Genetic Drift, Histocompatibility Antigens Class I, Haplotype, B vitamins, Haplotypes, Mutation, biology.protein, Chickens |
| الوصف: | Compared with the MHC of typical mammals, the chicken MHC (BF/BL region) of the B12 haplotype is smaller, simpler, and rearranged, with two classical class I genes of which only one is highly expressed. In this study, we describe the development of long-distance PCR to amplify some or all of each class I gene separately, allowing us to make the following points. First, six other haplotypes have the same genomic organization as B12, with a poorly expressed (minor) BF1 gene between DMB2 and TAP2 and a well-expressed (major) BF2 gene between TAP2 and C4. Second, the expression of the BF1 gene is crippled in three different ways in these haplotypes: enhancer A deletion (B12, B19), enhancer A divergence and transcription start site deletion (B2, B4, B21), and insertion/rearrangement leading to pseudogenes (B14, B15). Third, the three kinds of alterations in the BF1 gene correspond to dendrograms of the BF1 and poorly expressed class II B (BLB1) genes reflecting mostly neutral changes, while the dendrograms of the BF2 and well-expressed class II (BLB2) genes each have completely different topologies reflecting selection. The common pattern for the poorly expressed genes reflects the fact the BF/BL region undergoes little recombination and allows us to propose a pattern of descent for these chicken MHC haplotypes from a common ancestor. Taken together, these data explain how stable MHC haplotypes predominantly express a single class I molecule, which in turn leads to striking associations of the chicken MHC with resistance to infectious pathogens and response to vaccines. |
| تدمد: | 1550-6606 0022-1767 |
| URL الوصول: | https://explore.openaire.eu/search/publication?articleId=doi_dedup___::cfbd63489443100a4cae59bd262a8e55 https://doi.org/10.4049/jimmunol.178.9.5744 |
| حقوق: | OPEN |
| رقم الأكسشن: | edsair.doi.dedup.....cfbd63489443100a4cae59bd262a8e55 |
| قاعدة البيانات: | OpenAIRE |
| تدمد: | 15506606 00221767 |
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