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Rocos NIE, Coulter FJ, Tan TCJ, Kaufman J. The minor chicken class I gene BF1 is deleted between short imperfect direct repeats in the B14 and typical B15 major histocompatibility complex (MHC) haplotypes. Immunogenetics 2023; 75:455-464. [PMID: 37405420 PMCID: PMC10514180 DOI: 10.1007/s00251-023-01313-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2023] [Accepted: 06/10/2023] [Indexed: 07/06/2023]
Abstract
The chicken major histocompatibility complex (MHC, also known as the BF-BL region of the B locus) is notably small and simple with few genes, most of which are involved in antigen processing and presentation. There are two classical class I genes, of which only BF2 is well and systemically expressed as the major ligand for cytotoxic T lymphocytes (CTLs). The other class I gene, BF1, is believed to be primarily a natural killer (NK) cell ligand. Among most standard chicken MHC haplotypes examined in detail, BF1 is expressed tenfold less than BF2 at the RNA level due to defects in the promoter or in a splice site. However, in the B14 and typical B15 haplotypes, BF1 RNA was not detected, and here, we show that a deletion between imperfect 32 nucleotide direct repeats has removed the BF1 gene entirely. The phenotypic effects of not having a BF1 gene (particularly on resistance to infectious pathogens) have not been systematically explored, but such deletions between short direct repeats are also found in some BF1 promoters and in the 5' untranslated region (5'UTR) of some BG genes found in the BG region of the B locus. Despite the opposite transcriptional orientation of homologous genes in the chicken MHC, which might prevent the loss of key genes from a minimal essential MHC, it appears that small direct repeats can still lead to deletion.
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Affiliation(s)
- Nicolas I. E. Rocos
- Institute of Immunology and Infection Research, University of Edinburgh, Charlotte Auerbach Road, Edinburgh, EH9 3FL UK
| | - Felicity J. Coulter
- Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QP UK
- Current Address: Oregon Health and Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239 USA
| | - Thomas C. J. Tan
- Institute of Immunology and Infection Research, University of Edinburgh, Charlotte Auerbach Road, Edinburgh, EH9 3FL UK
- Current Address: Wellcome Centre for Cell Biology, Max Born Crescent, Edinburgh, EH9 3BF UK
| | - Jim Kaufman
- Institute of Immunology and Infection Research, University of Edinburgh, Charlotte Auerbach Road, Edinburgh, EH9 3FL UK
- Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QP UK
- Department of Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge, CB3 0ES UK
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Han L, Wu S, Zhang T, Peng W, Zhao M, Yue C, Wen W, Cai W, Li M, Wallny HJ, Avila DW, Mwangi W, Nair V, Ternette N, Guo Y, Zhao Y, Chai Y, Qi J, Liang H, Gao GF, Kaufman J, Liu WJ. A Wider and Deeper Peptide-Binding Groove for the Class I Molecules from B15 Compared with B19 Chickens Correlates with Relative Resistance to Marek's Disease. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2023; 210:668-680. [PMID: 36695776 PMCID: PMC7614295 DOI: 10.4049/jimmunol.2200211] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Accepted: 12/19/2022] [Indexed: 01/26/2023]
Abstract
The chicken MHC is known to confer decisive resistance or susceptibility to various economically important pathogens, including the iconic oncogenic herpesvirus that causes Marek's disease (MD). Only one classical class I gene, BF2, is expressed at a high level in chickens, so it was relatively easy to discern a hierarchy from well-expressed thermostable fastidious specialist alleles to promiscuous generalist alleles that are less stable and expressed less on the cell surface. The class I molecule BF2*1901 is better expressed and more thermostable than the closely related BF2*1501, but the peptide motif was not simpler as expected. In this study, we confirm for newly developed chicken lines that the chicken MHC haplotype B15 confers resistance to MD compared with B19. Using gas phase sequencing and immunopeptidomics, we find that BF2*1901 binds a greater variety of amino acids in some anchor positions than does BF2*1501. However, by x-ray crystallography, we find that the peptide-binding groove of BF2*1901 is narrower and shallower. Although the self-peptides that bound to BF2*1901 may appear more various than those of BF2*1501, the structures show that the wider and deeper peptide-binding groove of BF2*1501 allows stronger binding and thus more peptides overall, correlating with the expected hierarchies for expression level, thermostability, and MD resistance. Our study provides a reasonable explanation for greater promiscuity for BF2*1501 compared with BF2*1901, corresponding to the difference in resistance to MD.
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Affiliation(s)
- Lingxia Han
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150001, China
- National Poultry Laboratory Animal Resource Center, Harbin 150001, China
- Heilongjiang Provincial Key Laboratory of Laboratory Animal and Comparative Medicine, Harbin 150069, China
| | - Shaolian Wu
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150001, China
- CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
| | - Ting Zhang
- Biosafety Level-3 Laboratory, Life Sciences Institute & Collaborative Innovation Centre of Regenerative Medicine and Medical BioResource Development and Application, Guangxi Medical University, Nanning, Guangxi 530021, China
- NHC Key Laboratory of Biosafety, National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 100052, China
| | - Weiyu Peng
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150001, China
- NHC Key Laboratory of Biosafety, National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 100052, China
| | - Min Zhao
- CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
| | - Can Yue
- NHC Key Laboratory of Biosafety, National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 100052, China
- Research Unit of Adaptive Evolution and Control of Emerging Viruses, Chinese Academy of Medical Sciences, Beijing 100052, China
- Savaid Medical School, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Wanxin Wen
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150001, China
| | - Wenbo Cai
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150001, China
| | - Min Li
- NHC Key Laboratory of Biosafety, National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 100052, China
| | | | - David W. Avila
- The Basel Institute for Immunology, Basel CH4001, Switzerland
| | - William Mwangi
- The Pirbright Institute, Pirbright GU24 0NF, United Kingdom
| | - Venugopal Nair
- The Pirbright Institute, Pirbright GU24 0NF, United Kingdom
- Department of Zoology, University of Oxford, Oxford OX1 3SZ, United Kingdom
| | - Nicola Ternette
- Nuffield Department of Medicine, University of Oxford, Headington OX37BN, United Kingdom
| | - Yaxin Guo
- NHC Key Laboratory of Biosafety, National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 100052, China
- Research Unit of Adaptive Evolution and Control of Emerging Viruses, Chinese Academy of Medical Sciences, Beijing 100052, China
| | - Yingze Zhao
- NHC Key Laboratory of Biosafety, National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 100052, China
- Research Unit of Adaptive Evolution and Control of Emerging Viruses, Chinese Academy of Medical Sciences, Beijing 100052, China
| | - Yan Chai
- CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
| | - Jianxun Qi
- CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
| | - Hao Liang
- Biosafety Level-3 Laboratory, Life Sciences Institute & Collaborative Innovation Centre of Regenerative Medicine and Medical BioResource Development and Application, Guangxi Medical University, Nanning, Guangxi 530021, China
| | - George F. Gao
- CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
- NHC Key Laboratory of Biosafety, National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 100052, China
- Research Unit of Adaptive Evolution and Control of Emerging Viruses, Chinese Academy of Medical Sciences, Beijing 100052, China
| | - Jim Kaufman
- The Basel Institute for Immunology, Basel CH4001, Switzerland
- Department of Pathology, University of Cambridge, Cambridge CB2 1QP, United Kingdom
- Department of Veterinary Science, University of Cambridge, Cambridge CB3 0ES, United Kingdom
- Institute for Immunology and Infection Research, University of Edinburgh, Edinburgh EH9 3FL, United Kingdom
| | - William J. Liu
- Biosafety Level-3 Laboratory, Life Sciences Institute & Collaborative Innovation Centre of Regenerative Medicine and Medical BioResource Development and Application, Guangxi Medical University, Nanning, Guangxi 530021, China
- NHC Key Laboratory of Biosafety, National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 100052, China
- Research Unit of Adaptive Evolution and Control of Emerging Viruses, Chinese Academy of Medical Sciences, Beijing 100052, China
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Card DC, Van Camp AG, Santonastaso T, Jensen-Seaman MI, Anthony NM, Edwards SV. Structure and evolution of the squamate major histocompatibility complex as revealed by two Anolis lizard genomes. Front Genet 2022; 13:979746. [PMID: 36425073 PMCID: PMC9679377 DOI: 10.3389/fgene.2022.979746] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Accepted: 10/20/2022] [Indexed: 11/10/2022] Open
Abstract
The major histocompatibility complex (MHC) is an important genomic region for adaptive immunity and has long been studied in ecological and evolutionary contexts, such as disease resistance and mate and kin selection. The MHC has been investigated extensively in mammals and birds but far less so in squamate reptiles, the third major radiation of amniotes. We localized the core MHC genomic region in two squamate species, the green anole (Anolis carolinensis) and brown anole (A. sagrei), and provide the first detailed characterization of the squamate MHC, including the presence and ordering of known MHC genes in these species and comparative assessments of genomic structure and composition in MHC regions. We find that the Anolis MHC, located on chromosome 2 in both species, contains homologs of many previously-identified mammalian MHC genes in a single core MHC region. The repetitive element composition in anole MHC regions was similar to those observed in mammals but had important distinctions, such as higher proportions of DNA transposons. Moreover, longer introns and intergenic regions result in a much larger squamate MHC region (11.7 Mb and 24.6 Mb in the green and brown anole, respectively). Evolutionary analyses of MHC homologs of anoles and other representative amniotes uncovered generally monophyletic relationships between species-specific homologs and a loss of the peptide-binding domain exon 2 in one of two mhc2β gene homologs of each anole species. Signals of diversifying selection in each anole species was evident across codons of mhc1, many of which appear functionally relevant given known structures of this protein from the green anole, chicken, and human. Altogether, our investigation fills a major gap in understanding of amniote MHC diversity and evolution and provides an important foundation for future squamate-specific or vertebrate-wide investigations of the MHC.
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Affiliation(s)
- Daren C. Card
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, United States
- Museum of Comparative Zoology, Harvard University, Cambridge, MA, United States
- *Correspondence: Daren C. Card,
| | - Andrew G. Van Camp
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, United States
- Museum of Comparative Zoology, Harvard University, Cambridge, MA, United States
| | - Trenten Santonastaso
- Department of Biological Sciences, University of New Orleans, New Orleans, LA, United States
| | | | - Nicola M. Anthony
- Department of Biological Sciences, University of New Orleans, New Orleans, LA, United States
| | - Scott V. Edwards
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, United States
- Museum of Comparative Zoology, Harvard University, Cambridge, MA, United States
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4
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Goto RM, Warden CD, Shiina T, Hosomichi K, Zhang J, Kang TH, Wu X, Glass MC, Delany ME, Miller MM. The Gallus gallus RJF reference genome reveals an MHCY haplotype organized in gene blocks that contain 107 loci including 45 specialized, polymorphic MHC class I loci, 41 C-type lectin-like loci, and other loci amid hundreds of transposable elements. G3 (BETHESDA, MD.) 2022; 12:jkac218. [PMID: 35997588 PMCID: PMC9635633 DOI: 10.1093/g3journal/jkac218] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Accepted: 08/15/2022] [Indexed: 06/15/2023]
Abstract
MHCY is a second major histocompatibility complex-like gene region in chickens originally identified by the presence of major histocompatibility complex class I-like and class II-like gene sequences. Up to now, the MHCY gene region has been poorly represented in genomic sequence data. A high density of repetitive sequence and multiple members of several gene families prevented the accurate assembly of short-read sequence data for MHCY. Identified here by single-molecule real-time sequencing sequencing of BAC clones for the Gallus gallus Red Jungle Fowl reference genome are 107 MHCY region genes (45 major histocompatibility complex class I-like, 41 c-type-lectin-like, 8 major histocompatibility complex class IIβ, 8 LENG9-like, 4 zinc finger protein loci, and a single only zinc finger-like locus) located amid hundreds of retroelements within 4 contigs representing the region. Sequences obtained for nearby ribosomal RNA genes have allowed MHCY to be precisely mapped with respect to the nucleolar organizer region. Gene sequences provide insights into the unusual structure of the MHCY class I molecules. The MHCY class I loci are polymorphic and group into 22 types based on predicted amino acid sequences. Some MHCY class I loci are full-length major histocompatibility complex class I genes. Others with altered gene structure are considered gene candidates. The amino acid side chains at many of the polymorphic positions in MHCY class I are directed away rather than into the antigen-binding groove as is typical of peptide-binding major histocompatibility complex class I molecules. Identical and nearly identical blocks of genomic sequence contribute to the observed multiplicity of identical MHCY genes and the large size (>639 kb) of the Red Jungle Fowl MHCY haplotype. Multiple points of hybridization observed in fluorescence in situ hybridization suggest that the Red Jungle Fowl MHCY haplotype is made up of linked, but physically separated genomic segments. The unusual gene content, the evidence of highly similar duplicated segments, and additional evidence of variation in haplotype size distinguish polymorphic MHCY from classical polymorphic major histocompatibility complex regions.
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Affiliation(s)
| | | | | | | | | | - Tae Hyuk Kang
- Integrative Genomics Core Facility, Beckman Research Institute, City of Hope, Duarte, CA 91010-3000, USA
| | - Xiwei Wu
- Integrative Genomics Core Facility, Beckman Research Institute, City of Hope, Duarte, CA 91010-3000, USA
| | | | | | - Marcia M Miller
- Corresponding author: Center for RNA Biology and Therapeutics, Beckman Research Institute, City of Hope, 1500 E. Duarte Road, Duarte, CA 91010-3000, USA.
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5
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Ediriweera TK, Manjula P, Cho E, Kim M, Lee JH. Application of next-generation sequencing for the high-resolution typing of MHC-B in Korean native chicken. Front Genet 2022; 13:886376. [DOI: 10.3389/fgene.2022.886376] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Accepted: 10/07/2022] [Indexed: 11/13/2022] Open
Abstract
The major histocompatibility complex-B (MHC-B) region of chicken is crucially important in their immunogenesis and highly diverse among different breeds, lines, and even populations. Because it determines the resistance/susceptibility to numerous infectious diseases, it is important to analyze this genomic region, particularly classical class I and II genes, to determine the variation and diversity that ultimately affect antigen presentation. This study investigated five lines of indigenous Korean native chicken (KNC) and the Ogye breed using next-generation sequencing (NGS) data with Geneious Prime-based assembly and variant calling with the Genome Analysis Toolkit (GATK) best practices pipeline. The consensus sequences of MHC-B (BG1-BF2) were obtained for each chicken line/breed and their variants were analyzed. All of the Korean native chicken lines possessed an excessive number of variants, including an ample amount of high-impact variants that provided useful information regarding modified major histocompatibility complex molecules. The study confirmed that next-generation sequencing techniques can effectively be used to detect MHC variabilities and the KNC lines are highly diverse for the MHC-B region, suggesting a substantial divergence from red junglefowl.
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Some thoughts about what non-mammalian jawed vertebrates are telling us about antigen processing and peptide loading of MHC molecules. Curr Opin Immunol 2022; 77:102218. [PMID: 35687979 PMCID: PMC9586880 DOI: 10.1016/j.coi.2022.102218] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Revised: 03/19/2022] [Accepted: 05/10/2022] [Indexed: 12/11/2022]
Abstract
The major histocompatibility complex (MHC) of mammals encodes highly polymorphic classical class I and class II molecules with crucial roles in immune responses, as well as various nonclassical molecules encoded by the MHC and elsewhere in the genome that have a variety of functions. These MHC molecules are supported by antigen processing and peptide loading pathways which are well-understood in mammals. This review considers what has been learned about the MHC, MHC molecules and the supporting pathways in non-mammalian jawed vertebrates. From the initial understanding from work with the chicken MHC, a great deal of diversity in the structure and function has been found. Are there underlying principles? The genomic organisation of the MHC varies enormously across jawed vertebrates. Total numbers of MHC genes vary among vertebrates, with only a few classical MHC genes. Some nonclassical MHC and classical pathway genes appear earlier than others. Obvious co-evolution within MHC pathways occurs in some species, but not others. The promiscuity of interactions may correlate with differences in genomic organisation.
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7
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Otto M, Zheng Y, Wiehe T. Recombination, selection and the evolution of tandem gene arrays. Genetics 2022; 221:6572811. [PMID: 35460227 PMCID: PMC9252282 DOI: 10.1093/genetics/iyac052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Accepted: 03/17/2022] [Indexed: 11/16/2022] Open
Abstract
Multigene families—immunity genes or sensory receptors, for instance—are often subject to diversifying selection. Allelic diversity may be favored not only through balancing or frequency-dependent selection at individual loci but also by associating different alleles in multicopy gene families. Using a combination of analytical calculations and simulations, we explored a population genetic model of epistatic selection and unequal recombination, where a trade-off exists between the benefit of allelic diversity and the cost of copy abundance. Starting from the neutral case, where we showed that gene copy number is Gamma distributed at equilibrium, we derived also the mean and shape of the limiting distribution under selection. Considering a more general model, which includes variable population size and population substructure, we explored by simulations mean fitness and some summary statistics of the copy number distribution. We determined the relative effects of selection, recombination, and demographic parameters in maintaining allelic diversity and shaping the mean fitness of a population. One way to control the variance of copy number is by lowering the rate of unequal recombination. Indeed, when encoding recombination by a rate modifier locus, we observe exactly this prediction. Finally, we analyzed the empirical copy number distribution of 3 genes in human and estimated recombination and selection parameters of our model.
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Affiliation(s)
- Moritz Otto
- Institut für Genetik, Universität zu Köln, Zülpicher Straße 47a, 50674 Köln, Germany
| | - Yichen Zheng
- Institut für Genetik, Universität zu Köln, Zülpicher Straße 47a, 50674 Köln, Germany
| | - Thomas Wiehe
- Institut für Genetik, Universität zu Köln, Zülpicher Straße 47a, 50674 Köln, Germany
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Miyamae J, Okano M, Nishiya K, Katakura F, Kulski JK, Moritomo T, Shiina T. Haplotype structures and polymorphisms of dog leukocyte antigen (DLA) class I loci shaped by intralocus and interlocus recombination events. Immunogenetics 2022; 74:245-259. [PMID: 34993565 DOI: 10.1007/s00251-021-01234-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Accepted: 11/10/2021] [Indexed: 11/26/2022]
Abstract
The dog leukocyte antigen (DLA) class I genomic region is located on chromosome 12, and the class I genomic region is composed of at least two distinct haplotypic gene structures, DLA-88-DLA-12 and DLA-88-DLA-88L. However, detailed information of the genomic differences among DLA-88, DLA-12, and DLA-88L are still lacking at the full-length gene level, and therefore, DLA allelic sequences classified for each of these loci are limited in number so far. In this study, we determined the DNA sequence of a 95-kb DLA class I genomic region including DLA-88, DLA-12/88L, and DLA-64 with three DLA homozygous dogs and of 37 full-length allelic gene sequences for DLA-88 and DLA-12/88L loci in 26 DLA class I homozygous dogs. Nucleotide diversity profiles of the 95-kb regions and sequence identity scores of the allelic sequences suggested that DLA-88L is a hybrid gene generated by interlocus and/or intralocus gene conversion between DLA-88 and DLA-12. The putative minimum conversion tract was estimated to be at least an 850-bp segment in length located from the 5´flanking untranslated region to the end of intron 2. In addition, at least one DLA-12 allele (DLA-12*004:01) was newly generated by interlocus gene conversion. In conclusion, the analysis for the occurrence of gene conversion within the dog DLA class I region revealed intralocus gene conversion tracts in 17 of 27 DLA-88 alleles and two of 10 DLA-12 alleles, suggesting that intralocus gene conversion has played an important role in expanding DLA allelic variations.
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Affiliation(s)
- Jiro Miyamae
- Faculty of Veterinary Medicine, Okayama University of Science, 1-3 Ikoino-oka, Imabari, Ehime, 794-8555, Japan.
| | - Masaharu Okano
- Department of Legal Medicine, Nihon University School of Dentistry, 1-8-13 Kanda-Surugadai, Chiyoda-ku, Tokyo, 101-8310, Japan
| | - Kohei Nishiya
- Department of Veterinary Medicine, College of Bioresource Science, Nihon University, 1866 Kameino, Fujisawa, Kanagawa, 252-0880, Japan
| | - Fumihiko Katakura
- Department of Veterinary Medicine, College of Bioresource Science, Nihon University, 1866 Kameino, Fujisawa, Kanagawa, 252-0880, Japan
| | - Jerzy K Kulski
- Discipline of Psychiatry, Medical School, The University of Western Australia, Crawley, WA, Australia
- Department of Molecular Life Science, Division of Basic Medical Science and Molecular Medicine, Tokai University School of Medicine, 143 Shimokasuya, Isehara, Kanagawa, 259-1143, Japan
| | - Tadaaki Moritomo
- Department of Veterinary Medicine, College of Bioresource Science, Nihon University, 1866 Kameino, Fujisawa, Kanagawa, 252-0880, Japan
| | - Takashi Shiina
- Department of Molecular Life Science, Division of Basic Medical Science and Molecular Medicine, Tokai University School of Medicine, 143 Shimokasuya, Isehara, Kanagawa, 259-1143, Japan
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9
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Jin Y, Wang W, Yu M, Hao M, Zeng G, Chen J, Dai J, Wu Y. Study on the contrast of the MHC–peptide interaction of B2/B21 haplotype and MHC‐related virus resistance in chickens. Immun Inflamm Dis 2021; 9:1670-1677. [PMID: 34473901 PMCID: PMC8589374 DOI: 10.1002/iid3.520] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2021] [Revised: 08/16/2021] [Accepted: 08/18/2021] [Indexed: 01/05/2023] Open
Abstract
Introduction Methods Results Conclusion
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Affiliation(s)
- Yuan‐chang Jin
- College of Biology and Agriculture (College of Food Science and Technology) Zunyi Normal College Zunyi Guizhou China
| | - Wei Wang
- School of Life Science Hunan University of Science and Technology Xiangtan Hunan China
| | - Min‐min Yu
- College of Biology and Agriculture (College of Food Science and Technology) Zunyi Normal College Zunyi Guizhou China
| | - Mei‐lin Hao
- College of Biology and Agriculture (College of Food Science and Technology) Zunyi Normal College Zunyi Guizhou China
| | - Gang Zeng
- College of Biology and Agriculture (College of Food Science and Technology) Zunyi Normal College Zunyi Guizhou China
| | - Jing‐fen Chen
- College of Biology and Agriculture (College of Food Science and Technology) Zunyi Normal College Zunyi Guizhou China
| | - Juan Dai
- College of Biology and Agriculture (College of Food Science and Technology) Zunyi Normal College Zunyi Guizhou China
| | - Yu‐jie Wu
- College of Biology and Agriculture (College of Food Science and Technology) Zunyi Normal College Zunyi Guizhou China
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10
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Almeida T, Ohta Y, Gaigher A, Muñoz-Mérida A, Neves F, Castro LFC, Machado AM, Esteves PJ, Veríssimo A, Flajnik MF. A Highly Complex, MHC-Linked, 350 Million-Year-Old Shark Nonclassical Class I Lineage. THE JOURNAL OF IMMUNOLOGY 2021; 207:824-836. [PMID: 34301841 DOI: 10.4049/jimmunol.2000851] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Accepted: 05/09/2021] [Indexed: 11/19/2022]
Abstract
Cartilaginous fish, or Chondrichthyes, are the oldest extant vertebrates to possess the MHC and the Ig superfamily-based Ag receptors, the defining genes of the gnathostome adaptive immune system. In this work, we have identified a novel MHC lineage, UEA, a complex multigene nonclassical class I family found in sharks (division Selachii) but not detected in chimaeras (subclass Holocephali) or rays (division Batoidea). This new lineage is distantly related to the previously reported nonclassical class I lineage UCA, which appears to be present only in dogfish sharks (order Squaliformes). UEA lacks conservation of the nine invariant residues in the peptide (ligand)-binding regions (PBR) that bind to the N and C termini of bound peptide in most vertebrate classical class I proteins, which are replaced by relatively hydrophobic residues compared with the classical UAA. In fact, UEA and UCA proteins have the most hydrophobic-predicted PBR of all identified chondrichthyan class I molecules. UEA genes detected in the whale shark and bamboo shark genome projects are MHC linked. Consistent with UEA comprising a very large gene family, we detected weak expression in different tissues of the nurse shark via Northern blotting and RNA sequencing. UEA genes fall into three sublineages with unique characteristics in the PBR. UEA shares structural and genetic features with certain nonclassical class I genes in other vertebrates, such as the highly complex XNC nonclassical class I genes in Xenopus, and we anticipate that each shark gene, or at least each sublineage, will have a unique function, perhaps in bacterial defense.
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Affiliation(s)
- Tereza Almeida
- CIBIO-InBIO, Centro de Investigacão em Biodiversidade e Recursos Genéticos, Campus Agrário de Vairão, Universidade do Porto, Vairão, Porto, Portugal.,Departamento de Biologia, Faculdade de Ciências da Universidade do Porto, Porto, Portugal.,Department of Microbiology and Immunology, University of Maryland Baltimore, Baltimore, MD; and
| | - Yuko Ohta
- Department of Microbiology and Immunology, University of Maryland Baltimore, Baltimore, MD; and
| | - Arnaud Gaigher
- CIBIO-InBIO, Centro de Investigacão em Biodiversidade e Recursos Genéticos, Campus Agrário de Vairão, Universidade do Porto, Vairão, Porto, Portugal
| | - Antonio Muñoz-Mérida
- CIBIO-InBIO, Centro de Investigacão em Biodiversidade e Recursos Genéticos, Campus Agrário de Vairão, Universidade do Porto, Vairão, Porto, Portugal
| | - Fabiana Neves
- CIBIO-InBIO, Centro de Investigacão em Biodiversidade e Recursos Genéticos, Campus Agrário de Vairão, Universidade do Porto, Vairão, Porto, Portugal
| | - L Filipe C Castro
- Departamento de Biologia, Faculdade de Ciências da Universidade do Porto, Porto, Portugal.,Interdisciplinary Centre of Marine and Environmental Research, University of Porto, Porto, Portugal
| | - André M Machado
- Interdisciplinary Centre of Marine and Environmental Research, University of Porto, Porto, Portugal
| | - Pedro J Esteves
- CIBIO-InBIO, Centro de Investigacão em Biodiversidade e Recursos Genéticos, Campus Agrário de Vairão, Universidade do Porto, Vairão, Porto, Portugal.,Departamento de Biologia, Faculdade de Ciências da Universidade do Porto, Porto, Portugal
| | - Ana Veríssimo
- CIBIO-InBIO, Centro de Investigacão em Biodiversidade e Recursos Genéticos, Campus Agrário de Vairão, Universidade do Porto, Vairão, Porto, Portugal
| | - Martin F Flajnik
- Department of Microbiology and Immunology, University of Maryland Baltimore, Baltimore, MD; and
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11
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Tregaskes CA, Kaufman J. Chickens as a simple system for scientific discovery: The example of the MHC. Mol Immunol 2021; 135:12-20. [PMID: 33845329 PMCID: PMC7611830 DOI: 10.1016/j.molimm.2021.03.019] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 03/08/2021] [Accepted: 03/17/2021] [Indexed: 01/07/2023]
Abstract
Chickens have played many roles in human societies over thousands of years, most recently as an important model species for scientific discovery, particularly for embryology, virology and immunology. In the last few decades, biomedical models like mice have become the most important model organism for understanding the mechanisms of disease, but for the study of outbred populations, they have many limitations. Research on humans directly addresses many questions about disease, but frank experiments into mechanisms are limited by practicality and ethics. For research into all levels of disease simultaneously, chickens combine many of the advantages of humans and of mice, and could provide an independent, integrated and overarching system to validate and/or challenge the dogmas that have arisen from current biomedical research. Moreover, some important systems are simpler in chickens than in typical mammals. An example is the major histocompatibility complex (MHC) that encodes the classical MHC molecules, which play crucial roles in the innate and adaptive immune systems. Compared to the large and complex MHCs of typical mammals, the chicken MHC is compact and simple, with single dominantly-expressed MHC molecules that can determine the response to infectious pathogens. As a result, some fundamental principles have been easier to discover in chickens, with the importance of generalist and specialist MHC alleles being the latest example.
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Affiliation(s)
- Clive A Tregaskes
- University of Cambridge, Department of Pathology, Tennis Court Road, Cambridge, CB2 1QP, United Kingdom
| | - Jim Kaufman
- University of Cambridge, Department of Pathology, Tennis Court Road, Cambridge, CB2 1QP, United Kingdom; University of Edinburgh, Institute for Immunology and Infection Research, Ashworth Laboratories, Kings Buildings, Edinburgh, EH9 3FL, United Kingdom.
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12
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Manjula P, Kim M, Cho S, Seo D, Lee JH. High Levels of Genetic Variation in MHC-Linked Microsatellite Markers from Native Chicken Breeds. Genes (Basel) 2021; 12:240. [PMID: 33567601 PMCID: PMC7915948 DOI: 10.3390/genes12020240] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Revised: 02/01/2021] [Accepted: 02/04/2021] [Indexed: 12/12/2022] Open
Abstract
The major histocompatibility complex (MHC) is a highly polymorphic gene region that regulates cellular communication in all specific immune responses. In this study, we investigated 11 microsatellite (MS) markers in the MHC-B region of chicken populations from four countries: Sri Lanka, Bangladesh, South Korea, and Nigeria. The MS markers were divided into two sets. Set 1 included five novel MS markers, which we assessed using 192 samples from 21 populations. Set 2 included six previously reported markers, which we assessed using 881 samples from 29 populations. The Set 1 MS markers had lower polymorphism (polymorphic information content (PIC) < 0.5) than the Set 2 markers (PIC = 0.4-0.9). In all populations, the LEI0258 marker was the most polymorphic, with a total of 38 alleles (PIC = 0.912, expected heterozygosity (He) = 0.918). Local populations from Sri Lanka, Bangladesh, and Nigeria had higher allele diversity and more haplotypes for Set 2 MS markers than Korean and commercial populations. The Sri Lankan Karuwalagaswewa village population had the highest MHC diversity (mean allele number = 8.17, He = 0.657), whereas the white leghorn population had the lowest (mean allele number = 2.33, He = 0.342). A total of 409 haplotypes (89 shared and 320 unique), with a range of 4 (Rhode Island red) to 46 (Karuwalagaswewa village (TA)), were identified. Among the shared haplotypes, the B21-like haplotype was identified in 15 populations. The genetic relationship observed in a neighbour-joining tree based on the DA distance agreed with the breeding histories and geographic separations. The results indicated high MHC diversity in the local chicken populations. The difference in the allelic pattern among populations presumably reflects the effects of different genotypes, environments, geographic variation, and breeding policies in each country. The selection of MHC allele in domestic poultry can vary due to intensification of poultry production. Preserved MHC diversity in local chicken provides a great opportunity for future studies that address the relationships between MHC polymorphisms and differential immune responses.
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Affiliation(s)
| | | | | | | | - Jun Heon Lee
- Division of Animal and Dairy Science, Chungnam National University, Daejeon 34134, Korea; (P.M.); (M.K.); (S.C.); (D.S.)
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13
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Three functional mutation sites affect the immune response of pigs through altering the expression pattern and IgV domain of the CD4 protein. BMC Mol Cell Biol 2020; 21:91. [PMID: 33297958 PMCID: PMC7724863 DOI: 10.1186/s12860-020-00333-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Accepted: 11/24/2020] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The CD4 protein is an important surface marker of T lymphocytes, which can mediate the antigen presentation process by interacting with MHC II and TCR molecules in human and mouse. RESULTS In this study, two haplotypes (A and B) of the CD4 gene were found within Chinese indigenous and Western commercial pig breeds. These two haplotypes were defined by 22 fully linked SNPs in the CDS region of the CD4 gene. The expression level and localization of the CD4 protein were significantly different between haplotypes A and B. Transcriptome analysis revealed that the immune response-related genes and signaling pathways were down-regulated in genotype AA. Finally, three linked functional SNPs were identified, which affected the expression level and membrane localization of the CD4 protein in pigs. These three SNPs led to the replacements of two amino acids in the IgV1 domain of the CD4 protein, and related to the function of the CD4 protein in the immune response. CONCLUSION These three linked SNPs were the key functional mutation sites in the CD4 gene, which played important roles in the immune response, and could be utilized as new molecular markers in breeding for disease resistance in pigs.
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14
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Cruz-López M, Fernández G, Hipperson H, Palacios E, Cavitt J, Galindo-Espinosa D, Gómez Del Angel S, Pruner R, Gonzalez O, Burke T, Küpper C. Allelic diversity and patterns of selection at the major histocompatibility complex class I and II loci in a threatened shorebird, the Snowy Plover (Charadrius nivosus). BMC Evol Biol 2020; 20:114. [PMID: 32912143 PMCID: PMC7488298 DOI: 10.1186/s12862-020-01676-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2019] [Accepted: 08/20/2020] [Indexed: 12/02/2022] Open
Abstract
Background Understanding the structure and variability of adaptive loci such as the major histocompatibility complex (MHC) genes is a primary research goal for evolutionary and conservation genetics. Typically, classical MHC genes show high polymorphism and are under strong balancing selection, as their products trigger the adaptive immune response in vertebrates. Here, we assess the allelic diversity and patterns of selection for MHC class I and class II loci in a threatened shorebird with highly flexible mating and parental care behaviour, the Snowy Plover (Charadrius nivosus) across its broad geographic range. Results We determined the allelic and nucleotide diversity for MHC class I and class II genes using samples of 250 individuals from eight breeding population of Snowy Plovers. We found 40 alleles at MHC class I and six alleles at MHC class II, with individuals carrying two to seven different alleles (mean 3.70) at MHC class I and up to two alleles (mean 1.45) at MHC class II. Diversity was higher in the peptide-binding region, which suggests balancing selection. The MHC class I locus showed stronger signatures of both positive and negative selection than the MHC class II locus. Most alleles were present in more than one population. If present, private alleles generally occurred at very low frequencies in each population, except for the private alleles of MHC class I in one island population (Puerto Rico, lineage tenuirostris). Conclusion Snowy Plovers exhibited an intermediate level of diversity at the MHC, similar to that reported in other Charadriiformes. The differences found in the patterns of selection between the class I and II loci are consistent with the hypothesis that different mechanisms shape the sequence evolution of MHC class I and class II genes. The rarity of private alleles across populations is consistent with high natal and breeding dispersal and the low genetic structure previously observed at neutral genetic markers in this species.
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Affiliation(s)
- Medardo Cruz-López
- Posgrado en Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México, Ciudad Universitaria, 04510, Cd. México, Mexico.
| | - Guillermo Fernández
- Unidad Académica Mazatlán, Instituto de Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México, Apartado Postal 811, 82040, Mazatlán, Sinaloa, Mexico
| | - Helen Hipperson
- NERC Biomolecular Analysis Facility, Department of Animal and Plant Sciences, University of Sheffield, Sheffield, S10 2TN, UK
| | - Eduardo Palacios
- Centro de Investigación Científica y de Educación Superior de Ensenada, Unidad La Paz, Miraflores 334, Col. Bellavista, 23050, La Paz, Baja California Sur, Mexico
| | - John Cavitt
- Avian Ecology Laboratory Department of Zoology, Weber State University, Ogden, UT, 84408, USA
| | - Daniel Galindo-Espinosa
- Departamento Académico de Ciencias Marinas y Costeras, Universidad Autónoma de Baja California Sur, Carretera al Sur km 5.5, A.P. 19-B, 23080, La Paz, B.C.S., Mexico
| | - Salvador Gómez Del Angel
- Posgrado en Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México, Ciudad Universitaria, 04510, Cd. México, Mexico
| | - Raya Pruner
- Florida Fish and Wildlife Conservation Commission, Fish and Wildlife Research Institute, Panama City, FL, USA
| | - Oscar Gonzalez
- Grupo Aves del Perú, Gómez del Carpio 135, Barrio Medico, 34, Lima, Peru.,Department of Natural Sciences, Emmanuel College, Franklin Springs, GA, 30369, USA
| | - Terry Burke
- NERC Biomolecular Analysis Facility, Department of Animal and Plant Sciences, University of Sheffield, Sheffield, S10 2TN, UK
| | - Clemens Küpper
- Max Planck Institute for Ornithology, Eberhard-Gwinner-Strasse, 82319, Seewiesen, Germany.
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15
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Manjula P, Bed'Hom B, Hoque MR, Cho S, Seo D, Chazara O, Lee SH, Lee JH. Genetic diversity of MHC-B in 12 chicken populations in Korea revealed by single-nucleotide polymorphisms. Immunogenetics 2020; 72:367-379. [PMID: 32839847 DOI: 10.1007/s00251-020-01176-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Accepted: 08/17/2020] [Indexed: 01/07/2023]
Abstract
This study used a single-nucleotide polymorphism (SNP) panel to characterise the diversity in the major histocompatibility complex B region (MHC-B) in 12 chicken populations in Korea. Samples were genotyped for 96 MHC-B SNPs using an Illumina GoldenGate genotyping assay. The MHC-B SNP haplotypes were predicted using 58 informative SNPs and a coalescence-based Bayesian algorithm implemented by the PHASE program and a manual curation process. In total, 117 haplotypes, including 24 shared and 93 unique haplotypes, were identified. The unique haplotype numbers ranged from 0 in Rhode Island Red to 32 in the Korean native commercial chicken population 2 ("Hanhyup-3ho"). Population and haplotype principal component analysis (PCA) indicated no clear population structure based on the MHC haplotypes. Three haplotype clusters (A, B, C) segregated in these populations highlighted the relationship between the haplotypes in each cluster. The sequences from two clusters (B and C) overlapped, whereas the sequences from the third cluster (A) were very different. Overall, native breeds had high genetic diversity in the MHC-B region compared with the commercial breeds. This highlights their immune capabilities and genetic potential for resistance to many different pathogens.
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Affiliation(s)
- Prabuddha Manjula
- Division of Animal and Dairy Science, College of Agriculture and Life Sciences, Chungnam National University, Daejeon, 34134, Republic of Korea
| | - Bertrand Bed'Hom
- GABI, INRA, AgroParisTech, Université Paris-Saclay, 78350, Jouy-en-Josas, France
- Institut de Systématique, Evolution, Biodiversité (ISYEB), Muséum National d'Histoire Naturelle, CNRS, Sorbonne Université, EPHE, Université des Antilles, 75005, Paris, France
| | | | - Sunghyun Cho
- Division of Animal and Dairy Science, College of Agriculture and Life Sciences, Chungnam National University, Daejeon, 34134, Republic of Korea
| | - Dongwon Seo
- Division of Animal and Dairy Science, College of Agriculture and Life Sciences, Chungnam National University, Daejeon, 34134, Republic of Korea
| | - Olympe Chazara
- GABI, INRA, AgroParisTech, Université Paris-Saclay, 78350, Jouy-en-Josas, France
- Department of Pathology and Centre for Trophoblast Research, University of Cambridge, Cambridge, UK
| | - Seung Hwan Lee
- Division of Animal and Dairy Science, College of Agriculture and Life Sciences, Chungnam National University, Daejeon, 34134, Republic of Korea
| | - Jun Heon Lee
- Division of Animal and Dairy Science, College of Agriculture and Life Sciences, Chungnam National University, Daejeon, 34134, Republic of Korea.
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16
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Fulton JE. Advances in methodologies for detecting MHC-B variability in chickens. Poult Sci 2020; 99:1267-1274. [PMID: 32111304 PMCID: PMC7587895 DOI: 10.1016/j.psj.2019.11.029] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2019] [Revised: 11/08/2019] [Accepted: 11/08/2019] [Indexed: 11/19/2022] Open
Abstract
The chicken major histocompatibility B complex (MHC-B) region is of great interest owing to its very strong association with resistance to many diseases. Variation in the MHC-B was initially identified by hemagglutination of red blood cells with specific alloantisera. New technologies, developed to identify variation in biological materials, have been applied to the chicken MHC. Protein variation encoded by the MHC genes was examined by immunoprecipitation and 2-dimensional gel electrophoresis. Increased availability of DNA probes, PCR, and sequencing resulted in the application of DNA-based methods for MHC detection. The chicken reference genome, completed in 2004, allowed further refinements in DNA methods that enabled more rapid examination of MHC variation and extended such analyses to include very diverse chicken populations. This review progresses from the inception of MHC-B identification to the present, describing multiple methods, plus their advantages and disadvantages.
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Affiliation(s)
- J E Fulton
- Research and Development, Hy-Line International, Dallas Center, IA 50063, USA.
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17
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Potts ND, Bichet C, Merat L, Guitton E, Krupa AP, Burke TA, Kennedy LJ, Sorci G, Kaufman J. Development and optimization of a hybridization technique to type the classical class I and class II B genes of the chicken MHC. Immunogenetics 2019; 71:647-663. [PMID: 31761978 PMCID: PMC6900278 DOI: 10.1007/s00251-019-01149-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2019] [Accepted: 11/17/2019] [Indexed: 01/02/2023]
Abstract
The classical class I and class II molecules of the major histocompatibility complex (MHC) play crucial roles in immune responses to infectious pathogens and vaccines as well as being important for autoimmunity, allergy, cancer and reproduction. These classical MHC genes are the most polymorphic known, with roughly 10,000 alleles in humans. In chickens, the MHC (also known as the BF-BL region) determines decisive resistance and susceptibility to infectious pathogens, but relatively few MHC alleles and haplotypes have been described in any detail. We describe a typing protocol for classical chicken class I (BF) and class II B (BLB) genes based on a hybridization method called reference strand-mediated conformational analysis (RSCA). We optimize the various steps, validate the analysis using well-characterized chicken MHC haplotypes, apply the system to type some experimental lines and discover a new chicken class I allele. This work establishes a basis for typing the MHC genes of chickens worldwide and provides an opportunity to correlate with microsatellite and with single nucleotide polymorphism (SNP) typing for approaches involving imputation.
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Affiliation(s)
- Nicola D Potts
- Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QP, UK.,LGC Ltd., Newmarket Road, Fordham, Ely, CB7 5WW, UK
| | - Coraline Bichet
- BioGéoSciences, CNRS UMR 5561, Université de Bourgogne Franche-Comté, 6 Boulevard Gabriel, 21000, Dijon, France.,Institute of Avian Research, An der Vogelwarte 21, 26386, Wilhelmshaven, Germany
| | - Laurence Merat
- Plate-Forme d'Infectiologie Expérimentale (PFIE), UE-1277, INRA Centre Val de Loire, 37380, Nouzilly, France
| | - Edouard Guitton
- Plate-Forme d'Infectiologie Expérimentale (PFIE), UE-1277, INRA Centre Val de Loire, 37380, Nouzilly, France
| | - Andrew P Krupa
- Department of Animal and Plant Sciences, University of Sheffield, Western Bank, S10 2TN, Sheffield, UK
| | - Terry A Burke
- Department of Animal and Plant Sciences, University of Sheffield, Western Bank, S10 2TN, Sheffield, UK
| | - Lorna J Kennedy
- Division of Population Health, Health Services Research & Primary Care, University of Manchester, Oxford Road, M13 9PL, Manchester, UK
| | - Gabriele Sorci
- BioGéoSciences, CNRS UMR 5561, Université de Bourgogne Franche-Comté, 6 Boulevard Gabriel, 21000, Dijon, France
| | - Jim Kaufman
- Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QP, UK. .,Department of Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge, CB3 0ES, UK.
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18
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Afrache H, Tregaskes CA, Kaufman J. A potential nomenclature for the Immuno Polymorphism Database (IPD) of chicken MHC genes: progress and problems. Immunogenetics 2019; 72:9-24. [PMID: 31741010 PMCID: PMC6971145 DOI: 10.1007/s00251-019-01145-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2019] [Accepted: 10/20/2019] [Indexed: 12/25/2022]
Abstract
Among the genes with the highest allelic polymorphism and sequence diversity are those encoding the classical class I and class II molecules of the major histocompatibility complex (MHC). Although many thousands of MHC sequences have been deposited in general sequence databases like GenBank, the availability of curated MHC sequences with agreed nomenclature has been enormously beneficial. Along with the Immuno Polymorphism Database-IMunoGeneTics/human leukocyte antigen (IPD-IMGT/HLA) database, a collection of databases for curated sequences of immune importance has been developed. A recent addition is an IPD-MHC database for chickens. For many years, the nomenclature system for chicken MHC genes has been based on a list of standard, presumed to be stable, haplotypes. However, these standard haplotypes give different names to identical sequences. Moreover, the discovery of new recombinants between haplotypes and a rapid increase in newly discovered alleles leaves the old system untenable. In this review, a new nomenclature is considered, for which alleles of different loci are given names based on the system used for other MHCs, and then haplotypes are named according to the alleles present. The new nomenclature system is trialled, first with standard haplotypes and then with validated sequences from the scientific literature. In the trial, some class II B sequences were found in both class II loci, presumably by gene conversion or inversion, so that identical sequences would receive different names. This situation prompts further suggestions to the new nomenclature system. In summary, there has been progress, but also problems, with the new IPD-MHC system for chickens.
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Affiliation(s)
- Hassnae Afrache
- Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QP, UK
| | - Clive A Tregaskes
- Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QP, UK
| | - Jim Kaufman
- Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QP, UK. .,Department of Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge, CB2 0ES, UK.
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19
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20
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Qurkhuli T, Schwensow N, Brändel SD, Tschapka M, Sommer S. Can extreme MHC class I diversity be a feature of a wide geographic range? The example of Seba's short-tailed bat (Carollia perspicillata). Immunogenetics 2019; 71:575-587. [PMID: 31520134 PMCID: PMC7079943 DOI: 10.1007/s00251-019-01128-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Accepted: 08/14/2019] [Indexed: 12/19/2022]
Abstract
The major histocompatibility complex (MHC) is one of the most diverse genetic regions under pathogen-driven selection because of its central role in antigen binding and immunity. The highest MHC variability, both in terms of the number of individual alleles and gene copies, has so far been found in passerine birds; this is probably attributable to passerine adaptation to both a wide geographic range and a diverse array of habitats. If extraordinary high MHC variation and duplication rates are adaptive features under selection during the evolution of ecologically and taxonomically diverse species, then similarly diverse MHC architectures should be found in bats. Bats are an extremely species-rich mammalian group that is globally widely distributed. Many bat species roost in multitudinous groups and have high contact rates with pathogens, conspecifics, and allospecifics. We have characterized the MHC class I diversity in 116 Panamanian Seba's short-tailed bats (Carollia perspicillata), a widely distributed, generalist, neotropical species. We have detected a remarkable individual and population-level diversity of MHC class I genes, with between seven and 22 alleles and a unique genotype in each individual. This diversity is comparable with that reported in passerine birds and, in both taxonomic groups, further variability has evolved through length polymorphisms. Our findings support the hypothesis that, for species with a geographically broader range, high MHC class I variability is particularly adaptive. Investigation of the details of the underlying adaptive processes and the role of the high MHC diversity in pathogen resistance are important next steps for a better understanding of the role of bats in viral evolution and as carriers of several deadly zoonotic viruses.
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Affiliation(s)
- Tamar Qurkhuli
- Institute for Evolutionary Ecology and Conservation Genomics, University of Ulm, Albert-Einstein Allee 11, 89081, Ulm, Germany
| | - Nina Schwensow
- Institute for Evolutionary Ecology and Conservation Genomics, University of Ulm, Albert-Einstein Allee 11, 89081, Ulm, Germany
| | - Stefan Dominik Brändel
- Institute for Evolutionary Ecology and Conservation Genomics, University of Ulm, Albert-Einstein Allee 11, 89081, Ulm, Germany
- Smithsonian Tropical Research Institute, Apartado, 0843-03092, Panamá, República de Panamá
| | - Marco Tschapka
- Institute for Evolutionary Ecology and Conservation Genomics, University of Ulm, Albert-Einstein Allee 11, 89081, Ulm, Germany
- Smithsonian Tropical Research Institute, Apartado, 0843-03092, Panamá, República de Panamá
| | - Simone Sommer
- Institute for Evolutionary Ecology and Conservation Genomics, University of Ulm, Albert-Einstein Allee 11, 89081, Ulm, Germany.
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21
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Gao C, Xin C, Wang X, Quan J, Li C, Wang J, Chen H. Molecular genetic characterization and haplotype diversity of swine leukocyte antigen in Chinese Rongshui miniature pigs. Mol Immunol 2019; 112:215-222. [PMID: 31177058 DOI: 10.1016/j.molimm.2019.05.009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2018] [Revised: 01/30/2019] [Accepted: 05/28/2019] [Indexed: 10/26/2022]
Abstract
The Rongshui miniature pig is an important model animal for studying livestock disease prevention and control in China. The highly polymorphic swine leukocyte antigen (SLA) has been the focus of considerable interest because of the strong, reproducible associations between particular SLA haplotypes and infectious diseases. In this study, we identified 42 alleles at eight polymorphic SLA loci (SLA-1, SLA-3, SLA-2, SLA-6, DRA, DRB1, DQA, and DQB1) representing seven class I and six class II haplotypes using reverse transcription-polymerase chain reaction (RT-PCR) sequence-based typing and PCR-sequence specific primers in Rongshui miniature pigs. The official names were designated by the SLA Nomenclature Committee of the International Society for Animal Genetics. Seven class I haplotypes, Hp-5b.0, 86.0, 87.0, 88.0, 89.0, 90.0 and 91.0, and four class II haplotypes, Hp-0.18b, 0.19c, 0.41 and 0.47, had not previously been reported in other pig breeds. We also comprehensively analyzed the molecular genetic characterization and phylogenies of the identified alleles and the SLA haplotype diversity in Rongshui miniature pigs. SLA-1 and SLA-6 genes were under positive selection, while SLA-2 was under neutral selection, and the other five genes were under purifying selection. The highly polymorphic new alleles may be derived by nucleotide mutations, insertions and deletions, and fragment recombination, and alleles segregated based on sequence differences and peptide-binding motifs, rather than on pig breed. SLA haplotype diversity was generated by allele/gene conversion and recombination. These results will be helpful for elucidating the molecular genetic mechanisms influencing differential disease resistance among pigs with different SLA haplotypes.
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Affiliation(s)
- Caixia Gao
- State Key Laboratory of Veterinary Biotechnology, Heilongjiang Provincial Key Laboratory of Laboratory Animal and Comparative Medicine, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Harbin, 150069, China
| | - Chang Xin
- State Key Laboratory of Veterinary Biotechnology, Heilongjiang Provincial Key Laboratory of Laboratory Animal and Comparative Medicine, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Harbin, 150069, China
| | - Xiuying Wang
- State Key Laboratory of Veterinary Biotechnology, Heilongjiang Provincial Key Laboratory of Laboratory Animal and Comparative Medicine, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Harbin, 150069, China
| | - Jinqiang Quan
- State Key Laboratory of Veterinary Biotechnology, Heilongjiang Provincial Key Laboratory of Laboratory Animal and Comparative Medicine, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Harbin, 150069, China
| | - Changwen Li
- State Key Laboratory of Veterinary Biotechnology, Heilongjiang Provincial Key Laboratory of Laboratory Animal and Comparative Medicine, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Harbin, 150069, China
| | - Jingyu Wang
- Laboratory Animal Center, Dalian Medical University, Dalian, 116027, China
| | - Hongyan Chen
- State Key Laboratory of Veterinary Biotechnology, Heilongjiang Provincial Key Laboratory of Laboratory Animal and Comparative Medicine, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Harbin, 150069, China.
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22
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Minias P, Pikus E, Anderwald D. Allelic diversity and selection at the MHC class I and class II in a bottlenecked bird of prey, the White-tailed Eagle. BMC Evol Biol 2019; 19:2. [PMID: 30611206 PMCID: PMC6321662 DOI: 10.1186/s12862-018-1338-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Accepted: 12/17/2018] [Indexed: 01/07/2023] Open
Abstract
Background Genes of the Major Histocompatibility Complex (MHC) are essential for adaptive immune response in vertebrates, as they encode receptors that recognize peptides derived from the processing of intracellular (MHC class I) and extracellular (MHC class II) pathogens. High MHC diversity in natural populations is primarily generated and maintained by pathogen-mediated diversifying and balancing selection. It is, however, debated whether selection at the MHC can counterbalance the effects of drift in bottlenecked populations. The aim of this study was to assess allelic diversity of MHC genes in a recently bottlenecked bird of prey, the White-tailed Eagle Haliaeetus albicilla, as well as to compare mechanisms that shaped the evolution of MHC class I and class II in this species. Results We showed that significant levels of MHC diversity were retained in the core Central European (Polish) population of White-tailed Eagles. Ten MHC class I and 17 MHC class II alleles were recovered in total and individual birds showed high average MHC diversity (3.80 and 6.48 MHC class I and class II alleles per individual, respectively). Distribution of alleles within individuals provided evidence for the presence of at least three class I and five class II loci the White-tailed Eagle, which suggests recent duplication events. MHC class II showed greater sequence polymorphism than MHC class I and there was much stronger signature of diversifying selection acting on MHC class II than class I. Phylogenetic analysis provided evidence for trans-species similarity of class II, but not class I, sequences, which is likely consistent with stronger balancing selection at MHC class II. Conclusions Relatively high MHC diversity retained in the White-tailed Eagles from northern Poland reinforces high conservation value of local eagle populations. At the same time, our study is the first to demonstrate contrasting patterns of allelic diversity and selection at MHC class I and class II in an accipitrid species, supporting the hypothesis that different mechanisms can shape evolutionary trajectories of MHC class I and class II genes. Electronic supplementary material The online version of this article (10.1186/s12862-018-1338-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Piotr Minias
- Department of Biodiversity Studies and Bioeducation, Faculty of Biology and Environmental Protection, University of Łódź, Banacha 1/3, 90-237, Łódź, Poland.
| | - Ewa Pikus
- Department of Biodiversity Studies and Bioeducation, Faculty of Biology and Environmental Protection, University of Łódź, Banacha 1/3, 90-237, Łódź, Poland
| | - Dariusz Anderwald
- Eagle Conservation Committee, Niepodległości 53/55, 10-044, Olsztyn, Poland
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23
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Ballingall KT, Bontrop RE, Ellis SA, Grimholt U, Hammond JA, Ho CS, Kaufman J, Kennedy LJ, Maccari G, Miller D, Robinson J, Marsh SGE. Comparative MHC nomenclature: report from the ISAG/IUIS-VIC committee 2018. Immunogenetics 2018; 70:625-632. [PMID: 30039257 DOI: 10.1007/s00251-018-1073-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2018] [Accepted: 07/13/2018] [Indexed: 12/24/2022]
Abstract
Significant progress has been made over the last decade in defining major histocompatibility complex (MHC) diversity at the nucleotide, allele, haplotype, diplotype, and population levels in many non-human species. Much of this progress has been driven by the increased availability and reduced costs associated with nucleotide sequencing technologies. This report provides an update on the activities of the comparative MHC nomenclature committee which is a standing committee of both the International Society for Animal Genetics (ISAG) and the International Union of Immunological Societies (IUIS) where it operates under the umbrella of the Veterinary Immunology Committee (VIC). A previous report from this committee in 2006 defined the role of the committee in providing guidance in the development of a standardized nomenclature for genes and alleles at MHC loci in non-human species. It described the establishment of the Immuno Polymorphism Database, IPD-MHC, which continues to provide public access to high quality MHC sequence data across a range of species. In this report, guidelines for the continued development of a universal MHC nomenclature framework are described, summarizing the continued development of each species section within the IPD-MHC project.
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Affiliation(s)
- Keith T Ballingall
- Moredun Research Institute, Midlothian, UK and Chair of the Comparative MHC Nomenclature Committee, Edinburgh, Scotland, UK.
| | | | | | | | | | | | | | - Lorna J Kennedy
- Centre for Integrated Genomic Medical Research, Manchester, UK
| | - Giuseppe Maccari
- The Pirbright Institute, Pirbright, Surrey, UK.,Anthony Nolan Research Institute, London, UK
| | - Donald Miller
- Baker Institute for Animal Health, College of Veterinary Medicine, Cornell University, Ithaca, NY, USA
| | - James Robinson
- Anthony Nolan Research Institute, London, UK.,UCL Cancer Institute, Royal Free Campus, London, UK
| | - Steven G E Marsh
- Anthony Nolan Research Institute, London, UK.,UCL Cancer Institute, Royal Free Campus, London, UK
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24
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Athrey G, Faust N, Hieke ASC, Brisbin IL. Effective population sizes and adaptive genetic variation in a captive bird population. PeerJ 2018; 6:e5803. [PMID: 30356989 PMCID: PMC6196071 DOI: 10.7717/peerj.5803] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Accepted: 09/21/2018] [Indexed: 12/31/2022] Open
Abstract
Captive populations are considered a key component of ex situ conservation programs. Research on multiple taxa has shown the differential success of maintaining demographic versus genetic stability and viability in captive populations. In typical captive populations, usually founded by few or related individuals, genetic diversity can be lost and inbreeding can accumulate rapidly, calling into question their ultimate utility for release into the wild. Furthermore, domestication selection for survival in captive conditions is another concern. Therefore, it is crucial to understand the dynamics of population sizes, particularly the effective population size, and genetic diversity at non-neutral and adaptive loci in captive populations. In this study, we assessed effective population sizes and genetic variation at both neutral microsatellite markers, as well as SNP variants from the MHC-B locus of a captive Red Junglefowl population. This population represents a rare instance of a population with a well-documented history in captivity, following a realistic scenario of chain-of-custody, unlike many captive lab populations. Our analyses, which included 27 individuals comprising the entirety of one captive population show very low neutral and adaptive genetic variation, as well as low effective sizes, which correspond with the known demographic history. Finally, our study also shows the divergent impacts of small effective size and inbreeding in captive populations on microsatellite versus adaptive genetic variation in the MHC-B locus. Our study provides insights into the difficulties of maintaining adaptive genetic variation in small captive populations.
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Affiliation(s)
- Giridhar Athrey
- Department of Poultry Science, Texas A&M University, College Station, TX, United States of America.,Faculty of Ecology and Evolutionary Biology, Texas A&M University, College Station, TX, United States of America
| | - Nikolas Faust
- Department of Poultry Science, Texas A&M University, College Station, TX, United States of America
| | | | - I Lehr Brisbin
- Savannah River Ecology Lab, Aiken, SC, United States of America
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25
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Kaufman J. Generalists and Specialists: A New View of How MHC Class I Molecules Fight Infectious Pathogens. Trends Immunol 2018; 39:367-379. [PMID: 29396014 PMCID: PMC5929564 DOI: 10.1016/j.it.2018.01.001] [Citation(s) in RCA: 74] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Revised: 12/22/2017] [Accepted: 01/03/2018] [Indexed: 12/24/2022]
Abstract
In comparison with the major histocompatibility complexes (MHCs) of typical mammals, the chicken MHC is simple and compact with a single dominantly expressed class I molecule that can determine the immune response. In addition to providing useful information for the poultry industry and allowing insights into the evolution of the adaptive immune system, the simplicity of the chicken MHC has allowed the discovery of phenomena that are more difficult to discern in the more complicated mammalian systems. This review discusses the new concept that poorly expressed promiscuous class I alleles act as generalists to protect against a wide variety of infectious pathogens, while highly expressed fastidious class I alleles can act as specialists to protect against new and dangerous pathogens. A broad overview of classical MHC I expression and bound peptides reveals an inverse correlation between repertoire breadth and cell-surface expression in some chicken and human alleles. Several chicken class I alleles with wide peptide-binding repertoires (promiscuity) are associated with resistance to a variety of common diseases. Conversely, a narrow peptide-binding repertoire (fastidiousness) in some human HLA-B alleles is associated with resistance to HIV progression. Cell-surface expression of some classical class I alleles depends on the regulation of translocation to the cell surface rather than of transcription or translation. MHC translocation is influenced by peptide translocation in chickens and by tapasin interaction in humans.
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Affiliation(s)
- Jim Kaufman
- University of Cambridge, Department of Pathology, Tennis Court Road, Cambridge CB2 1QP, UK; University of Cambridge, Department of Veterinary Medicine, Madingley Road, Cambridge CB2 0ES, UK.
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26
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Identification of novel polymorphisms and two distinct haplotype structures in dog leukocyte antigen class I genes: DLA-88, DLA-12 and DLA-64. Immunogenetics 2017; 70:237-255. [DOI: 10.1007/s00251-017-1031-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2016] [Accepted: 09/19/2017] [Indexed: 12/14/2022]
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27
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Characterisation of MHC class I genes in the koala. Immunogenetics 2017; 70:125-133. [PMID: 28669101 DOI: 10.1007/s00251-017-1018-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2017] [Accepted: 06/20/2017] [Indexed: 10/19/2022]
Abstract
Koala (Phascolarctos cinereus) populations are on the decline across the majority of Australia's mainland. Two major diseases threatening the long-term survival of affected koala populations are caused by obligate intracellular pathogens: Chlamydia and koala retrovirus (KoRV). To improve our understanding of the koala immune system, we characterised their major histocompatibility complex (MHC) class I genes, which are centrally involved in presenting foreign peptides derived from intracellular pathogens to cytotoxic T cells. A total of 11 class I genes were identified in the koala genome. Three genes, Phci-UA, UB and UC, showed relatively high genetic variability and were expressed in all 12 examined tissues, whereas the other eight genes had tissue-specific expression and limited polymorphism. Evidence of diversifying selection was detected in Phci-UA and UC, while gene conversion may have played a role in creating new alleles at Phci-UB. We propose that Phci-UA, UB and UC are likely classical MHC genes of koalas, and further research is needed to understand their role in koala chlamydial and KoRV infections.
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28
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Chattaway J, Ramirez-Valdez RA, Chappell PE, Caesar JJE, Lea SM, Kaufman J. Different modes of variation for each BG lineage suggest different functions. Open Biol 2017; 6:rsob.160188. [PMID: 27628321 PMCID: PMC5043582 DOI: 10.1098/rsob.160188] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2016] [Accepted: 08/17/2016] [Indexed: 01/14/2023] Open
Abstract
Mammalian butyrophilins have various important functions, one for lipid binding but others as ligands for co-inhibition of αβ T cells or for stimulation of γδ T cells in the immune system. The chicken BG homologues are dimers, with extracellular immunoglobulin variable (V) domains joined by cysteines in the loop equivalent to complementarity-determining region 1 (CDR1). BG genes are found in three genomic locations: BG0 on chromosome 2, BG1 in the classical MHC (the BF-BL region) and many BG genes in the BG region just outside the MHC. Here, we show that BG0 is virtually monomorphic, suggesting housekeeping function(s) consonant with the ubiquitous tissue distribution. BG1 has allelic polymorphism but minimal sequence diversity, with the few polymorphic residues at the interface of the two V domains, suggesting that BG1 is recognized by receptors in a conserved fashion. Any phenotypic variation should be due to the intracellular region, with differential exon usage between alleles. BG genes in the BG region can generate diversity by exchange of sequence cassettes located in loops equivalent to CDR1 and CDR2, consonant with recognition of many ligands or antigens for immune defence. Unlike the mammalian butyrophilins, there are at least three modes by which BG genes evolve.
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Affiliation(s)
- John Chattaway
- Department of Pathology, University of Cambridge, Cambridge CB2 1QP, UK
| | | | - Paul E Chappell
- Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, UK
| | - Joseph J E Caesar
- Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, UK
| | - Susan M Lea
- Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, UK
| | - Jim Kaufman
- Department of Pathology, University of Cambridge, Cambridge CB2 1QP, UK Department of Veterinary Medicine, University of Cambridge, Cambridge CB3 0ES, UK
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29
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Parker A, Kaufman J. What chickens might tell us about the MHC class II system. Curr Opin Immunol 2017; 46:23-29. [PMID: 28433952 DOI: 10.1016/j.coi.2017.03.013] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2017] [Accepted: 03/24/2017] [Indexed: 11/15/2022]
Abstract
Almost all knowledge about the structure and function of MHC class II molecules outside of mammals comes from work with chickens. Most of the genes implicated in the class II system are present in chickens, so it is likely that the machinery of antigen processing and peptide-loading is similar to mammals. However, there is only one isotype (lineage) of classical class II genes, with one monomorphic DR-like BLA gene and two polymorphic BLB genes, located near one DMA and two DMB genes. The DMB2 and BLB2 genes are widely expressed at high levels, whereas the DMB1 and BLB1 genes are only expressed at highest levels in spleen and intestine, suggesting the possibility of two class II systems in chickens.
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Affiliation(s)
- Aimée Parker
- Institute of Food Research, Norwich Research Park, Norwich NR4 7UA, United Kingdom
| | - Jim Kaufman
- University of Cambridge, Department of Pathology, Cambridge CB2 1QP, United Kingdom; University of Cambridge, Department of Veterinary Medicine, Cambridge CB3 0ES, United Kingdom.
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30
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Fleming-Canepa X, Jensen SM, Mesa CM, Diaz-Satizabal L, Roth AJ, Parks-Dely JA, Moon DA, Wong JP, Evseev D, Gossen DA, Tetrault DG, Magor KE. Extensive Allelic Diversity of MHC Class I in Wild Mallard Ducks. THE JOURNAL OF IMMUNOLOGY 2016; 197:783-94. [PMID: 27342841 DOI: 10.4049/jimmunol.1502450] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2015] [Accepted: 05/31/2016] [Indexed: 11/19/2022]
Abstract
MHC class I is critically involved in defense against viruses, and diversity from polygeny and polymorphism contributes to the breadth of the immune response and health of the population. In this article, we examine MHC class I diversity in wild mallard ducks, the natural host and reservoir of influenza A viruses. We previously showed domestic ducks predominantly use UAA, one of five MHC class I genes, but whether biased expression is also true for wild mallards is unknown. Using RT-PCR from blood, we examined expressed MHC class I alleles from 38 wild mallards (Anas platyrhynchos) and identified 61 unique alleles, typically 1 or 2 expressed alleles in each individual. To determine whether expressed alleles correspond to UAA adjacent to TAP2 as in domestic ducks, we cloned and sequenced genomic UAA-TAP2 fragments from all mallards, which matched transcripts recovered and allowed us to assign most alleles as UAA Allelic differences are primarily located in α1 and α2 domains in the residues known to interact with peptide in mammalian MHC class I, suggesting the diversity is functional. Most UAA alleles have unique residues in the cleft predicting distinct specificity; however, six alleles have an unusual conserved cleft with two cysteine residues. Residues that influence peptide-loading properties and tapasin involvement in chicken are fixed in duck alleles and suggest tapasin independence. Biased expression of one MHC class I gene may make viral escape within an individual easy, but high diversity in the population places continual pressure on the virus in the reservoir species.
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Affiliation(s)
- Ximena Fleming-Canepa
- Department of Biological Sciences and the Li Ka Shing Institute of Virology, University of Alberta, Edmonton, Alberta T6G 2E9, Canada
| | - Shawna M Jensen
- Department of Biological Sciences and the Li Ka Shing Institute of Virology, University of Alberta, Edmonton, Alberta T6G 2E9, Canada
| | - Christine M Mesa
- Department of Biological Sciences and the Li Ka Shing Institute of Virology, University of Alberta, Edmonton, Alberta T6G 2E9, Canada
| | - Laura Diaz-Satizabal
- Department of Biological Sciences and the Li Ka Shing Institute of Virology, University of Alberta, Edmonton, Alberta T6G 2E9, Canada
| | - Alexa J Roth
- Department of Biological Sciences and the Li Ka Shing Institute of Virology, University of Alberta, Edmonton, Alberta T6G 2E9, Canada
| | - Julie A Parks-Dely
- Department of Biological Sciences and the Li Ka Shing Institute of Virology, University of Alberta, Edmonton, Alberta T6G 2E9, Canada
| | - Debra A Moon
- Department of Biological Sciences and the Li Ka Shing Institute of Virology, University of Alberta, Edmonton, Alberta T6G 2E9, Canada
| | - Janet P Wong
- Department of Biological Sciences and the Li Ka Shing Institute of Virology, University of Alberta, Edmonton, Alberta T6G 2E9, Canada
| | - Danyel Evseev
- Department of Biological Sciences and the Li Ka Shing Institute of Virology, University of Alberta, Edmonton, Alberta T6G 2E9, Canada
| | - Desolie A Gossen
- Department of Biological Sciences and the Li Ka Shing Institute of Virology, University of Alberta, Edmonton, Alberta T6G 2E9, Canada
| | - David G Tetrault
- Department of Biological Sciences and the Li Ka Shing Institute of Virology, University of Alberta, Edmonton, Alberta T6G 2E9, Canada
| | - Katharine E Magor
- Department of Biological Sciences and the Li Ka Shing Institute of Virology, University of Alberta, Edmonton, Alberta T6G 2E9, Canada
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31
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Pathogenicity of Genetically Similar, H5N1 Highly Pathogenic Avian Influenza Virus Strains in Chicken and the Differences in Sensitivity among Different Chicken Breeds. PLoS One 2016; 11:e0153649. [PMID: 27078641 PMCID: PMC4841636 DOI: 10.1371/journal.pone.0153649] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2015] [Accepted: 03/03/2016] [Indexed: 12/18/2022] Open
Abstract
Differences in the pathogenicity of genetically closely related H5N1 highly pathogenic avian influenza viruses (HPAIVs) were evaluated in White Leghorn chickens. These viruses varied in the clinical symptoms they induced, including lethality, virus shedding, and replication in host tissues. A comparison of the host responses in the lung, brain, and spleen suggested that the differences in viral replication efficiency were related to the host cytokine response at the early phase of infection, especially variations in the proinflammatory cytokine IL-6. Based on these findings, we inoculated the virus that showed the mildest pathogenicity among the five tested, A/pigeon/Thailand/VSMU-7-NPT/2004, into four breeds of Thai indigenous chicken, Phadu-Hung-Dang (PHD), Chee, Dang, and Luang-Hung-Khao (LHK), to explore effects of genetic background on host response. Among these breeds, Chee, Dang, and LHK showed significantly longer survival times than White Leghorns. Virus shedding from dead Thai indigenous chickens was significantly lower than that from White Leghorns. Although polymorphisms were observed in the Mx and MHC class I genes, there was no significant association between the polymorphisms in these loci and resistance to HPAIV.
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32
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Minias P, Bateson ZW, Whittingham LA, Johnson JA, Oyler-McCance S, Dunn PO. Contrasting evolutionary histories of MHC class I and class II loci in grouse--effects of selection and gene conversion. Heredity (Edinb) 2016; 116:466-76. [PMID: 26860199 DOI: 10.1038/hdy.2016.6] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2015] [Accepted: 12/18/2015] [Indexed: 11/09/2022] Open
Abstract
Genes of the major histocompatibility complex (MHC) encode receptor molecules that are responsible for recognition of intracellular and extracellular pathogens (class I and class II genes, respectively) in vertebrates. Given the different roles of class I and II MHC genes, one might expect the strength of selection to differ between these two classes. Different selective pressures may also promote different rates of gene conversion at each class. Despite these predictions, surprisingly few studies have looked at differences between class I and II genes in terms of both selection and gene conversion. Here, we investigated the molecular evolution of MHC class I and II genes in five closely related species of prairie grouse (Centrocercus and Tympanuchus) that possess one class I and two class II loci. We found striking differences in the strength of balancing selection acting on MHC class I versus class II genes. More than half of the putative antigen-binding sites (ABS) of class II were under positive or episodic diversifying selection, compared with only 10% at class I. We also found that gene conversion had a stronger role in shaping the evolution of MHC class II than class I. Overall, the combination of strong positive (balancing) selection and frequent gene conversion has maintained higher diversity of MHC class II than class I in prairie grouse. This is one of the first studies clearly demonstrating that macroevolutionary mechanisms can act differently on genes involved in the immune response against intracellular and extracellular pathogens.
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Affiliation(s)
- P Minias
- Department of Teacher Training and Biodiversity Studies, University of Łódź, Łódź, Poland.,Behavioral and Molecular Ecology Group, Department of Biological Sciences, University of Wisconsin-Milwaukee, Milwaukee, WI, USA
| | - Z W Bateson
- Behavioral and Molecular Ecology Group, Department of Biological Sciences, University of Wisconsin-Milwaukee, Milwaukee, WI, USA
| | - L A Whittingham
- Behavioral and Molecular Ecology Group, Department of Biological Sciences, University of Wisconsin-Milwaukee, Milwaukee, WI, USA
| | - J A Johnson
- Department of Biological Sciences, Institute of Applied Sciences, University of North Texas, Denton, TX, USA
| | - S Oyler-McCance
- Fort Collins Science Center, US Geological Survey, Fort Collins, CO, USA
| | - P O Dunn
- Behavioral and Molecular Ecology Group, Department of Biological Sciences, University of Wisconsin-Milwaukee, Milwaukee, WI, USA
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Fulton JE, McCarron AM, Lund AR, Pinegar KN, Wolc A, Chazara O, Bed'Hom B, Berres M, Miller MM. A high-density SNP panel reveals extensive diversity, frequent recombination and multiple recombination hotspots within the chicken major histocompatibility complex B region between BG2 and CD1A1. Genet Sel Evol 2016; 48:1. [PMID: 26743767 PMCID: PMC4705597 DOI: 10.1186/s12711-015-0181-x] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2015] [Accepted: 12/23/2015] [Indexed: 11/22/2022] Open
Abstract
BACKGROUND The major histocompatibility complex (MHC) is present within the genomes of all jawed vertebrates. MHC genes are especially important in regulating immune responses, but even after over 80 years of research on the MHC, much remains to be learned about how it influences adaptive and innate immune responses. In most species, the MHC is highly polymorphic and polygenic. Strong and highly reproducible associations are established for chicken MHC-B haplotypes in a number of infectious diseases. Here, we report (1) the development of a high-density SNP (single nucleotide polymorphism) panel for MHC-B typing that encompasses a 209,296 bp region in which 45 MHC-B genes are located, (2) how this panel was used to define chicken MHC-B haplotypes within a large number of lines/breeds and (3) the detection of recombinants which contributes to the observed diversity. METHODS A SNP panel was developed for the MHC-B region between the BG2 and CD1A1 genes. To construct this panel, each SNP was tested in end-point read assays on more than 7500 DNA samples obtained from inbred and commercially used egg-layer lines that carry known and novel MHC-B haplotypes. One hundred and one SNPs were selected for the panel. Additional breeds and experimentally-derived lines, including lines that carry MHC-B recombinant haplotypes, were then genotyped. RESULTS MHC-B haplotypes based on SNP genotyping were consistent with the MHC-B haplotypes that were assigned previously in experimental lines that carry B2, B5, B12, B13, B15, B19, B21, and B24 haplotypes. SNP genotyping resulted in the identification of 122 MHC-B haplotypes including a number of recombinant haplotypes, which indicate that crossing-over events at multiple locations within the region lead to the production of new MHC-B haplotypes. Furthermore, evidence of gene duplication and deletion was found. CONCLUSIONS The chicken MHC-B region is highly polymorphic across the surveyed 209-kb region that contains 45 genes. Our results expand the number of identified haplotypes and provide insights into the contribution of recombination events to MHC-B diversity including the identification of recombination hotspots and an estimation of recombination frequency.
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Affiliation(s)
| | | | | | | | - Anna Wolc
- Hy-Line International, Dallas Center, IA, USA.
- Iowa State University, 239C Kildee, Ames, IA, 50011, USA.
| | - Olympe Chazara
- Department of Pathology and Centre for Trophoblast Research, University of Cambridge, Cambridge, UK.
- Génétique Animale et Biologie Intégrative, INRA, AgroParisTech, Université Paris-Saclay, 78350, Jouy-en-Josas, France.
| | - Bertrand Bed'Hom
- Génétique Animale et Biologie Intégrative, INRA, AgroParisTech, Université Paris-Saclay, 78350, Jouy-en-Josas, France.
| | - Mark Berres
- Department of Animal Sciences, University of Wisconsin, Madison, USA.
| | - Marcia M Miller
- Department of Molecular and Cellular Biology, Beckman Research Institute, City of Hope, Duarte, CA, USA.
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Miller MM, Taylor RL. Brief review of the chicken Major Histocompatibility Complex: the genes, their distribution on chromosome 16, and their contributions to disease resistance. Poult Sci 2016; 95:375-92. [PMID: 26740135 PMCID: PMC4988538 DOI: 10.3382/ps/pev379] [Citation(s) in RCA: 94] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2015] [Accepted: 11/11/2015] [Indexed: 12/25/2022] Open
Abstract
Nearly all genes presently mapped to chicken chromosome 16 (GGA 16) have either a demonstrated role in immune responses or are considered to serve in immunity by reason of sequence homology with immune system genes defined in other species. The genes are best described in regional units. Among these, the best known is the polymorphic major histocompatibility complex-B (MHC-B) region containing genes for classical peptide antigen presentation. Nearby MHC-B is a small region containing two CD1 genes, which encode molecules known to bind lipid antigens and which will likely be found in chickens to present lipids to specialized T cells, as occurs with CD1 molecules in other species. Another region is the MHC-Y region, separated from MHC-B by an intervening region of tandem repeats. Like MHC-B, MHC-Y is polymorphic. It contains specialized class I and class II genes and c-type lectin-like genes. Yet another region, separated from MHC-Y by the single nucleolar organizing region (NOR) in the chicken genome, contains olfactory receptor genes and scavenger receptor genes, which are also thought to contribute to immunity. The structure, distribution, linkages and patterns of polymorphism in these regions, suggest GGA 16 evolves as a microchromosome devoted to immune defense. Many GGA 16 genes are polymorphic and polygenic. At the moment most disease associations are at the haplotype level. Roles of individual MHC genes in disease resistance are documented in only a very few instances. Provided suitable experimental stocks persist, the availability of increasingly detailed maps of GGA 16 genes combined with new means for detecting genetic variability will lead to investigations defining the contributions of individual loci and more applications for immunogenetics in breeding healthy poultry.
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Affiliation(s)
- Marcia M Miller
- Beckman Research Institute, City of Hope, Department of Molecular and Cellular Biology, Duarte, CA 91010
| | - Robert L Taylor
- Division of Animal and Nutritional Sciences, West Virginia University, Morgantown, WV 26506
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35
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Reed KM, Mendoza KM, Settlage RE. Targeted capture enrichment and sequencing identifies extensive nucleotide variation in the turkey MHC-B. Immunogenetics 2016; 68:219-29. [DOI: 10.1007/s00251-015-0893-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2015] [Accepted: 12/16/2015] [Indexed: 02/08/2023]
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What chickens would tell you about the evolution of antigen processing and presentation. Curr Opin Immunol 2015; 34:35-42. [DOI: 10.1016/j.coi.2015.01.001] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2014] [Revised: 12/30/2014] [Accepted: 01/02/2015] [Indexed: 01/04/2023]
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Gao C, Han L, Han J, Liu J, Jiang Q, Guo D, Qu L. Establishment of six homozygous MHC-B haplotype populations associated with susceptibility to Marek's disease in Chinese specific pathogen-free BWEL chickens. INFECTION GENETICS AND EVOLUTION 2014; 29:15-25. [PMID: 25445653 DOI: 10.1016/j.meegid.2014.10.031] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2014] [Revised: 10/23/2014] [Accepted: 10/29/2014] [Indexed: 10/24/2022]
Abstract
The highly polymorphic chicken major histocompatibility complex (MHC) is associated with different levels of immunologic responses to certain avian pathogens. MHC-B haplotype chickens are an important genetic resource for studying the genetic determination of pathogen resistance and susceptibility. The BWEL chicken population is the only specific pathogen-free (SPF) chickens bred and developed by the State Center of Poultry Genetic Resources of Laboratory Animals in China. In this study, we successfully established six homozygous MHC-B haplotype populations from the BWEL chickens using microsatellite marker technology, named as BW/G(1, 2, 3, 5, 6, 7) lines, and their molecular genotypes were matched to six serologically defined MHC-B haplotypes, B13, B15, B2, B5, B21 and B19, respectively. The sequences of BF genes exons 2 and 3 from four successive generations (F1-F4) of the BW/G(n) lines were completely consistent with those of serologically defined MHC-B haplotypes. Subsequently, six BW/G(n) line specific allo-antisera were prepared by immunization with red blood cells (RBCs) and hemagglutination tests results showed the BW/G(n) SPF chickens could be serologically differentiated. Additionally, susceptibility to Marek's disease (MD) in the BW/G3 (B2 haplotype) and BW/G7 (B19 haplotype) lines were determined by comparing mortality, macroscopic and histopathological lesions, and viral loads in feather pulp. The BW/G7 line showed greater genetic susceptibility to the very virulent MD virus (MDV) strain than the BW/G3 line. The establishment of MHC-B haplotype chicken populations associated with susceptibility to MD will be helpful for studying host immune responses and further developing the more effective vaccines in the context of MHC specificities, and they are also very useful for an understanding of MHC genes architecture and function.
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Affiliation(s)
- Caixia Gao
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Harbin 150001, China
| | - Lingxia Han
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Harbin 150001, China.
| | - Jianlin Han
- CAAS-ILRI Joint Laboratory on Livestock and Forage Genetic Resources, Institute of Animal Science, Chinese Academy of Agricultural Sciences (CAAS), Beijing 100193, China
| | - Jiasen Liu
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Harbin 150001, China
| | - Qian Jiang
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Harbin 150001, China
| | - Dongchun Guo
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Harbin 150001, China
| | - Liandong Qu
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Harbin 150001, China.
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Sequence of a complete chicken BG haplotype shows dynamic expansion and contraction of two gene lineages with particular expression patterns. PLoS Genet 2014; 10:e1004417. [PMID: 24901252 PMCID: PMC4046983 DOI: 10.1371/journal.pgen.1004417] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2013] [Accepted: 04/14/2014] [Indexed: 11/19/2022] Open
Abstract
Many genes important in immunity are found as multigene families. The butyrophilin genes are members of the B7 family, playing diverse roles in co-regulation and perhaps in antigen presentation. In humans, a fixed number of butyrophilin genes are found in and around the major histocompatibility complex (MHC), and show striking association with particular autoimmune diseases. In chickens, BG genes encode homologues with somewhat different domain organisation. Only a few BG genes have been characterised, one involved in actin-myosin interaction in the intestinal brush border, and another implicated in resistance to viral diseases. We characterise all BG genes in B12 chickens, finding a multigene family organised as tandem repeats in the BG region outside the MHC, a single gene in the MHC (the BF-BL region), and another single gene on a different chromosome. There is a precise cell and tissue expression for each gene, but overall there are two kinds, those expressed by haemopoietic cells and those expressed in tissues (presumably non-haemopoietic cells), correlating with two different kinds of promoters and 5′ untranslated regions (5′UTR). However, the multigene family in the BG region contains many hybrid genes, suggesting recombination and/or deletion as major evolutionary forces. We identify BG genes in the chicken whole genome shotgun sequence, as well as by comparison to other haplotypes by fibre fluorescence in situ hybridisation, confirming dynamic expansion and contraction within the BG region. Thus, the BG genes in chickens are undergoing much more rapid evolution compared to their homologues in mammals, for reasons yet to be understood. Many immune genes are multigene families, presumably in response to pathogen variation. Some multigene families undergo expansion and contraction, leading to copy number variation (CNV), presumably due to more intense selection. Recently, the butyrophilin family in humans and other mammals has come under scrutiny, due to genetic associations with autoimmune diseases as well as roles in immune co-regulation and antigen presentation. Butyrophilin genes exhibit allelic polymorphism, but gene number appears stable within a species. We found that the BG homologues in chickens are very different, with great changes between haplotypes. We characterised one haplotype in detail, showing that there are two single BG genes, one on chromosome 2 and the other in the major histocompatibility complex (BF-BL region) on chromosome 16, and a family of BG genes in a tandem array in the BG region nearby. These genes have specific expression in cells and tissues, but overall are expressed in either haemopoietic cells or tissues. The two singletons have relatively stable evolutionary histories, but the BG region undergoes dynamic expansion and contraction, with the production of hybrid genes. Thus, chicken BG genes appear to evolve much more quickly than their closest homologs in mammals, presumably due to increased pressure from pathogens.
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Dawes ME, Griggs LM, Collisson EW, Briles WE, Drechsler Y. Dramatic differences in the response of macrophages from B2 and B19 MHC-defined haplotypes to interferon gamma and polyinosinic:polycytidylic acid stimulation. Poult Sci 2014; 93:830-8. [PMID: 24706959 PMCID: PMC7107093 DOI: 10.3382/ps.2013-03511] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
The chicken MHC has been associated with disease resistance, though the mechanisms are not understood. The functions of macrophages, critical to both innate and acquired immunity, were compared between the more infectious bronchitis virus-resistant B2 and the more infectious bronchitis virus-susceptible B19 lines. In vivo peripheral blood concentrations of monocytes were similar in B2 or B19 homozygous haplotypes. Peripheral blood-derived macrophages were stimulated with poly I:C, simulating an RNA virus, or IFNγ, a cytokine at the interface of innate and adaptive immunity. Not only did B2-derived peripheral monocytes differentiate into macrophages more readily than the B19 monocytes, but as determined by NO production, macrophages from B2 and B2 on B19 genetic background chicks were also significantly more responsive to either stimulant. In conclusion, the correlation with resistance to illness following viral infection may be directly linked to a more vigorous innate immune response.
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Affiliation(s)
- Maisie E Dawes
- College of Veterinary Medicine, Western University of Health Sciences, 309 E. Second St., Pomona, CA 91766-1854
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Abernathy J, Li X, Jia X, Chou W, Lamont SJ, Crooijmans R, Zhou H. Copy number variation in Fayoumi and Leghorn chickens analyzed using array comparative genomic hybridization. Anim Genet 2014; 45:400-11. [DOI: 10.1111/age.12141] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/16/2014] [Indexed: 12/25/2022]
Affiliation(s)
- J. Abernathy
- Department of Animal Science; University of California; Davis CA 95616 USA
| | - X. Li
- College of Animal Science and Technology; Shandong Agricultural University; Taian Shandong 271018 China
- Department of Poultry Science; Texas A&M University; College Station TX 77843 USA
| | - X. Jia
- Department of Animal Science; University of California; Davis CA 95616 USA
- College of Animal Science and Technology; China Agricultural University; Beijing 100193 China
| | - W. Chou
- Department of Poultry Science; Texas A&M University; College Station TX 77843 USA
| | - S. J. Lamont
- Department of Animal Science; Iowa State University; Ames IA 50011 USA
| | - R. Crooijmans
- Animal Breeding and Genomics Centre; Wageningen University; Wageningen the Netherlands
| | - H. Zhou
- Department of Animal Science; University of California; Davis CA 95616 USA
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Alcaide M, Muñoz J, Martínez-de la Puente J, Soriguer R, Figuerola J. Extraordinary MHC class II B diversity in a non-passerine, wild bird: the Eurasian Coot Fulica atra (Aves: Rallidae). Ecol Evol 2014; 4:688-98. [PMID: 24683452 PMCID: PMC3967895 DOI: 10.1002/ece3.974] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2013] [Revised: 12/30/2013] [Accepted: 01/07/2014] [Indexed: 11/25/2022] Open
Abstract
The major histocompatibility complex (MHC) hosts the most polymorphic genes ever described in vertebrates. The MHC triggers the adaptive branch of the immune response, and its extraordinary variability is considered an evolutionary consequence of pathogen pressure. The last few years have witnessed the characterization of the MHC multigene family in a large diversity of bird species, unraveling important differences in its polymorphism, complexity, and evolution. Here, we characterize the first MHC class II B sequences isolated from a Rallidae species, the Eurasian Coot Fulica atra. A next-generation sequencing approach revealed up to 265 alleles that translated into 251 different amino acid sequences (β chain, exon 2) in 902 individuals. Bayesian inference identified up to 19 codons within the presumptive peptide-binding region showing pervasive evidence of positive, diversifying selection. Our analyses also detected a significant excess of high-frequency segregating sites (average Tajima's D = 2.36, P < 0.05), indicative of balancing selection. We found one to six different alleles per individual, consistent with the occurrence of at least three MHC class II B gene duplicates. However, the genotypes comprised of three alleles were by far the most abundant in the population investigated (49.4%), followed by those with two (29.6%) and four (17.5%) alleles. We suggest that these proportions are in agreement with the segregation of MHC haplotypes differing in gene copy number. The most widespread segregating haplotypes, according to our findings, would contain one single gene or two genes. The MHC class II of the Eurasian Coot is a valuable system to investigate the evolutionary implications of gene copy variation and extensive variability, the greatest ever found, to the best of our knowledge, in a wild population of a non-passerine bird.
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Affiliation(s)
- Miguel Alcaide
- Estación Biológica de Doñana – CSICAvda. Américo Vespucio s/n, 41092, Sevilla, Spain
| | - Joaquin Muñoz
- Estación Biológica de Doñana – CSICAvda. Américo Vespucio s/n, 41092, Sevilla, Spain
- The University of Oklahoma Biological Station15389 Station Road, Kingston, Oklahoma, 73439
| | | | - Ramón Soriguer
- Estación Biológica de Doñana – CSICAvda. Américo Vespucio s/n, 41092, Sevilla, Spain
| | - Jordi Figuerola
- Estación Biológica de Doñana – CSICAvda. Américo Vespucio s/n, 41092, Sevilla, Spain
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Bauer MM, Miller MM, Briles WE, Reed KM. Genetic variation at the MHC in a population of introduced wild turkeys. Anim Biotechnol 2013; 24:210-28. [PMID: 23777350 DOI: 10.1080/10495398.2013.767267] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Genetic variation in the major histocompatibility complex (MHC) is known to affect disease resistance in many species. Investigations of MHC diversity in populations of wild species have focused on the antigen presenting class IIβ molecules due to the known polymorphic nature of these genes and the role these molecules play in pathogen recognition. Studies of MHC haplotype variation in the turkey ( Meleagris gallopavo ) are limited. This study was designed to examine MHC diversity in a group of Eastern wild turkeys ( Meleagris gallopavo silvestris ) collected during population expansion following reintroduction of the species in southern Wisconsin, USA. Southern blotting with BG and class IIβ probes and single nucleotide polymorphism (SNP) genotyping was used to measure MHC variation. SNP analysis focused on single copy MHC genes flanking the highly polymorphic class IIβ genes. Southern blotting identified 27 class IIβ phenotypes, whereas SNP analysis identified 13 SNP haplotypes occurring in 28 combined genotypes. Results show that genetic diversity estimates based on RFLP (Southern blot) analysis underestimate the level of variation detected by SNP analysis. Sequence analysis of the mitochondrial D-loop identified 7 mitochondrial haplotypes (mitotypes) in the sampled birds. Results show that wild turkeys located in southern Wisconsin have a genetically diverse MHC and originate from several maternal lineages.
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Affiliation(s)
- Miranda M Bauer
- Department of Veterinary and Biomedical Sciences, College of Veterinary Medicine, University of Minnesota, St. Paul, MN, USA
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43
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Evolution of MHC class I in the order Crocodylia. Immunogenetics 2013; 66:53-65. [PMID: 24253731 DOI: 10.1007/s00251-013-0746-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2013] [Accepted: 11/01/2013] [Indexed: 10/26/2022]
Abstract
The major histocompatibility complex (MHC) is a dynamic genomic region with an essential role in the adaptive immunity of jawed vertebrates. The evolution of the MHC has been dominated by gene duplication and gene loss, commonly known as the birth-and-death process. Evolutionary studies of the MHC have mostly focused on model species. However, the investigation of this region in non-avian reptiles is still in its infancy. To provide insights into the evolutionary mechanisms that have shaped the diversity of this region in the Order Crocodylia, we investigated MHC class I exon 3, intron 3, and exon 4 across 20 species of the families Alligatoridae and Crocodilidae. We generated 124 DNA sequences and identified 31 putative functional variants as well as 14 null variants. Phylogenetic analyses revealed three gene groups, all of which were present in Crocodilidae but only one in Alligatoridae. Within these groups, variants generally appear to cluster at the genus or family level rather than in species-specific groups. In addition, we found variation in gene copy number and some indication of interlocus recombination. These results suggest that MHC class I in Crocodylia underwent independent events of gene duplication, particularly in Crocodilidae. These findings enhance our understanding of MHC class I evolution and provide a preliminary framework for comparative studies of other non-avian reptiles as well as diversity assessment within Crocodylia.
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Characteristics of MHC class I genes in house sparrows Passer domesticus as revealed by long cDNA transcripts and amplicon sequencing. J Mol Evol 2013; 77:8-21. [PMID: 23877344 DOI: 10.1007/s00239-013-9575-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2013] [Accepted: 07/10/2013] [Indexed: 10/26/2022]
Abstract
In birds the major histocompatibility complex (MHC) organization differs both among and within orders; chickens Gallus gallus of the order Galliformes have a simple arrangement, while many songbirds of the order Passeriformes have a more complex arrangement with larger numbers of MHC class I and II genes. Chicken MHC genes are found at two independent loci, classical MHC-B and non-classical MHC-Y, whereas non-classical MHC genes are yet to be verified in passerines. Here we characterize MHC class I transcripts (α1 to α3 domain) and perform amplicon sequencing using a next-generation sequencing technique on exon 3 from house sparrow Passer domesticus (a passerine) families. Then we use phylogenetic, selection, and segregation analyses to gain a better understanding of the MHC class I organization. Trees based on the α1 and α2 domain revealed a distinct cluster with short terminal branches for transcripts with a 6-bp deletion. Interestingly, this cluster was not seen in the tree based on the α3 domain. 21 exon 3 sequences were verified in a single individual and the average numbers within an individual were nine and five for sequences with and without a 6-bp deletion, respectively. All individuals had exon 3 sequences with and without a 6-bp deletion. The sequences with a 6-bp deletion have many characteristics in common with non-classical MHC, e.g., highly conserved amino acid positions were substituted compared with the other alleles, low nucleotide diversity and just a single site was subject to positive selection. However, these alleles also have characteristics that suggest they could be classical, e.g., complete linkage and absence of a distinct cluster in a tree based on the α3 domain. Thus, we cannot determine for certain whether or not the alleles with a 6-bp deletion are non-classical based on our present data. Further analyses on segregation patterns of these alleles in combination with dating the 6-bp deletion through MHC characterization across the genus Passer may solve this matter in the future.
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Alcaide M, Liu M, Edwards SV. Major histocompatibility complex class I evolution in songbirds: universal primers, rapid evolution and base compositional shifts in exon 3. PeerJ 2013; 1:e86. [PMID: 23781408 PMCID: PMC3685324 DOI: 10.7717/peerj.86] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2013] [Accepted: 05/23/2013] [Indexed: 01/04/2023] Open
Abstract
Genes of the Major Histocompatibility Complex (MHC) have become an important marker for the investigation of adaptive genetic variation in vertebrates because of their critical role in pathogen resistance. However, despite significant advances in the last few years the characterization of MHC variation in non-model species still remains a challenging task due to the redundancy and high variation of this gene complex. Here we report the utility of a single pair of primers for the cross-amplification of the third exon of MHC class I genes, which encodes the more polymorphic half of the peptide-binding region (PBR), in oscine passerines (songbirds; Aves: Passeriformes), a group especially challenging for MHC characterization due to the presence of large and complex MHC multigene families. In our survey, although the primers failed to amplify exon 3 from two suboscine passerine birds, they amplified exon 3 of multiple MHC class I genes in all 16 species of oscine songbirds tested, yielding a total of 120 sequences. The 16 songbird species belong to 14 different families, primarily within the Passerida, but also in the Corvida. Using a conservative approach based on the analysis of cloned amplicons (n = 16) from each species, we found between 3 and 10 MHC sequences per individual. Each allele repertoire was highly divergent, with the overall number of polymorphic sites per species ranging from 33 to 108 (out of 264 sites) and the average number of nucleotide differences between alleles ranging from 14.67 to 43.67. Our survey in songbirds allowed us to compare macroevolutionary dynamics of exon 3 between songbirds and non-passerine birds. We found compelling evidence of positive selection acting specifically upon peptide-binding codons across birds, and we estimate the strength of diversifying selection in songbirds to be about twice that in non-passerines. Analysis using comparative methods suggest weaker evidence for a higher GC content in the 3rd codon position of exon 3 in non-passerine birds, a pattern that contrasts with among-clade GC patterns found in other avian studies and may suggests different mutational mechanisms. Our primers represent a useful tool for the characterization of functional and evolutionarily relevant MHC variation across the hyperdiverse songbirds.
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Affiliation(s)
- Miguel Alcaide
- Department of Organismic and Evolutionary Biology and Museum of Comparative Zoology, Harvard University, Cambridge, MA, USA
| | - Mark Liu
- Department of Organismic and Evolutionary Biology and Museum of Comparative Zoology, Harvard University, Cambridge, MA, USA
| | - Scott V. Edwards
- Department of Organismic and Evolutionary Biology and Museum of Comparative Zoology, Harvard University, Cambridge, MA, USA
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Strand T, Wang B, Meyer-Lucht Y, Höglund J. Evolutionary history of black grouse major histocompatibility complex class IIB genes revealed through single locus sequence-based genotyping. BMC Genet 2013; 14:29. [PMID: 23617616 PMCID: PMC3652749 DOI: 10.1186/1471-2156-14-29] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2012] [Accepted: 04/12/2013] [Indexed: 11/10/2022] Open
Abstract
Background Gene duplications are frequently observed in the Major Histocompatibility Complex (MHC) of many species, and as a consequence loci belonging to the same MHC class are often too similar to tell apart. In birds, single locus genotyping of MHC genes has proven difficult due to concerted evolution homogenizing sequences at different loci. But studies on evolutionary history, mode of selection and heterozygosity correlations on the MHC cannot be performed before it is possible to analyse duplicated genes separately. In this study we investigate the architecture and evolution of the MHC class IIB genes in black grouse. We developed a sequence-based genotyping method for separate amplification of the two black grouse MHC class IIB genes BLB1 and BLB2. Based on this approach we are able to study differences in structure and selection between the two genes in black grouse and relate these results to the chicken MHC structure and organization. Results Sequences were obtained from 12 individuals and separated into alleles using the software PHASE. We compared nucleotide diversity measures and employed selection tests for BLB1 and BLB2 to explore their modes of selection. Both BLB1 and BLB2 are transcribed and display classic characteristics of balancing selection as predicted for expressed MHC class IIB genes. We found evidence for both intra- and interlocus recombination or gene conversion, as well as indication for positive but differential selection at both loci. Moreover, the two loci appear to be linked. Phylogenetic analyses revealed orthology of the black grouse MHC class IIB genes to the respective BLB loci in chicken. Conclusions The results indicate that the duplication of the BLB gene occurred before the species divergence into black grouse, chicken and pheasant. Further, we conclude that BLB1 and BLB2 in black grouse are subjected to homogenizing concerted evolution due to interlocus genetic exchange after species divergence. The loci are in linkage disequilibrium, which is in line with the theory of tightly coevolving genes within the MHC under the minimal essential MHC hypothesis. Our results support the conclusion that MHC form and function in birds derived from studies on the domesticated chicken are not artefacts of the domestication process.
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Affiliation(s)
- Tanja Strand
- Population Biology and Conservation Biology, Department of Ecology and Genetics, Evolutionary Biology Center, Uppsala University, Norbyvägen 18D, Uppsala, SE-752 36, Sweden
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Banat GR, Tkalcic S, Dzielawa JA, Jackwood MW, Saggese MD, Yates L, Kopulos R, Briles W, Collisson EW. Association of the chicken MHC B haplotypes with resistance to avian coronavirus. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2013; 39:430-437. [PMID: 23178407 PMCID: PMC7103219 DOI: 10.1016/j.dci.2012.10.006] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2012] [Revised: 10/18/2012] [Accepted: 10/19/2012] [Indexed: 06/01/2023]
Abstract
Clinical respiratory illness was compared in five homozygous chicken lines, originating from homozygous B2, B8, B12 and B19, and heterozygous B2/B12 birds after infection with either of two strains of the infectious bronchitis virus (IBV). All chickens used in these studies originated from White Leghorn and Ancona linages. IBV Gray strain infection of MHC homozygous B12 and B19 haplotype chicks resulted in severe respiratory disease compared to chicks with B2/B2 and B5/B5 haplotypes. Demonstrating a dominant B2 phenotype, B2/B12 birds were also more resistant to IBV. Respiratory clinical illness in B8/B8 chicks was severe early after infection, while illness resolved similar to the B5 and B2 homozygous birds. Following M41 strain infection, birds with B2/B2 and B8/B8 haplotypes were again more resistant to clinical illness than B19/B19 birds. Real time RT-PCR indicated that infection was cleared more efficiently in trachea, lungs and kidneys of B2/B2 and B8/B8 birds compared with B19/B19 birds. Furthermore, M41 infected B2/B2 and B8/B8 chicks performed better in terms of body weight gain than B19/B19 chicks. These studies suggest that genetics of B defined haplotypes might be exploited to produce chicks resistant to respiratory pathogens or with more effective immune responses.
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Key Words
- ibv, infectious bronchitis virus
- mhc, major histocompatibility complex
- m41, massachusetts 41
- rt-pcr, reverse transcription polymerase chain reaction
- sars, severe acute respiratory syndrome
- rsv, rous sarcoma virus
- mdv, marek’s disease virus
- spf, specific pathogen free
- pi, post infection
- eid50/ml, embryo infectious dose 50 per ml
- niu, northern illinois university
- pbs, phosphate buffer saline
- rna, ribonucleic acid
- 5′ utr, 5′ untranslated region
- bp, base pairs
- anova, analysis of variance
- ark, arkansas
- ctl, cytotoxic t lymphocyte
- aiv, avian influenza virus
- ifnγ, interferon gamma
- poly i:c, polyinosinic polycytidylic acid
- usda, united states department of agriculture
- nifa, national institute of food and agriculture
- infectious bronchitis virus
- chicken mhc b haplotype
- clinical illness
- infection of trachea
- lungs and kidneys
- resistant
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Affiliation(s)
- Ghida R. Banat
- College of Veterinary Medicine, Western University of Health Sciences, 309 E. 2nd St., Pomona, CA 91766-1854, USA
| | - Suzana Tkalcic
- College of Veterinary Medicine, Western University of Health Sciences, 309 E. 2nd St., Pomona, CA 91766-1854, USA
| | - Jennifer A. Dzielawa
- College of Veterinary Medicine, Texas A&M University, College Station, TX 77845, USA
| | - Mark W. Jackwood
- Poultry Diagnostic Research Center, Department of Population Health, College of Veterinary Medicine, University of Georgia, 953 College Station Road, Athens, GA 30602-4875, USA
| | - Miguel D. Saggese
- College of Veterinary Medicine, Western University of Health Sciences, 309 E. 2nd St., Pomona, CA 91766-1854, USA
| | - Linda Yates
- Department of Biological Sciences, Northern Illinois University, 415 Montgomery Hall, DeKalb, IL 60115-2861, USA
| | - Renee Kopulos
- Department of Biological Sciences, Northern Illinois University, 415 Montgomery Hall, DeKalb, IL 60115-2861, USA
| | - W.E. Briles
- Department of Biological Sciences, Northern Illinois University, 415 Montgomery Hall, DeKalb, IL 60115-2861, USA
| | - Ellen W. Collisson
- College of Veterinary Medicine, Western University of Health Sciences, 309 E. 2nd St., Pomona, CA 91766-1854, USA
- College of Veterinary Medicine, Texas A&M University, College Station, TX 77845, USA
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SUZUKI S, HOSOMICHI K, YOKOYAMA K, TSUDA K, HARA H, YOSHIDA Y, FUJIWARA A, MIZUTANI M, SHIINA T, KONO T, HANZAWA K. Primary analysis of DNA polymorphisms in theTRIMregion (MHCsubregion) of the Japanese quail,Coturnix japonica. Anim Sci J 2012; 84:90-6. [DOI: 10.1111/j.1740-0929.2012.01062.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2012] [Accepted: 07/24/2012] [Indexed: 11/29/2022]
Affiliation(s)
- Shingo SUZUKI
- Department of Molecular Life Science; Tokai University School of Medicine; Isehara
| | | | - Kana YOKOYAMA
- Department of Animal Science; Tokyo University of Agriculture; Atsugi
| | - Kaoru TSUDA
- Genome Research Center; Tokyo University of Agriculture; Tokyo
| | - Hiromi HARA
- Department of Animal Science; Tokyo University of Agriculture; Atsugi
| | - Yutaka YOSHIDA
- Department of Animal Science; Tokyo University of Agriculture; Atsugi
| | | | - Makoto MIZUTANI
- Avian Bioscience Research Center; Nagoya University of Graduate School of Bioagricultural Sciences; Nagoya
| | - Takashi SHIINA
- Department of Molecular Life Science; Tokai University School of Medicine; Isehara
| | | | - Kei HANZAWA
- Department of Animal Science; Tokyo University of Agriculture; Atsugi
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Gloria-Soria A, Moreno MA, Yund PO, Lakkis FG, Dellaporta SL, Buss LW. Evolutionary genetics of the hydroid allodeterminant alr2. Mol Biol Evol 2012; 29:3921-32. [PMID: 22855537 DOI: 10.1093/molbev/mss197] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
We surveyed genetic variation in alr2, an allodeterminant of the colonial hydroid Hydractinia symbiolongicarpus. We generated cDNA from a sample of 239 Hydractinia colonies collected at Lighthouse Point, Connecticut, and identified 473 alr2 alleles, 198 of which were unique. Rarefaction analysis suggested that the sample was near saturation. Most alleles were rare, with 86% occurring at frequencies of 1% or less. Alleles were highly variable, diverging on average by 18% of the amino acids in a predicted extracellular domain of the molecule. Analysis of 152 full-length alleles confirmed the existence of two structural types, defined by exons 4-8 of the gene. Several residues of the predicted immunoglobulin superfamily-like domains display signatures of positive selection. We also identified 77 unique alr2 pseudogene sequences from 85 colonies. Twenty-seven of these sequences matched expressed alr2 sequences from other colonies. This observation is consistent with pseudogenes contributing to alr2 diversification through sequence donation. A more limited collection of animals was made from a distant, relict population of H. symbiolongicarpus. Sixty percent of the unique sequences identified in this sample were found to match sequences from the Lighthouse Point population. The large number of alr2 alleles, their degree of divergence, the predominance of rare alleles in the population, their persistence over broad spatial and temporal scales, and the signatures of positive selection in multiple residues of the putative recognition domain paint a consistent picture of negative-frequency-dependent selection operating in this system. The genetic diversity observed at alr2 is comparable to that of the most highly polymorphic genetic systems known to date.
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Zhang L, Katselis GS, Moore RE, Lekpor K, Goto RM, Hunt HD, Lee TD, Miller MM. MHC class I target recognition, immunophenotypes and proteomic profiles of natural killer cells within the spleens of day-14 chick embryos. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2012; 37:446-456. [PMID: 22446732 DOI: 10.1016/j.dci.2012.03.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2012] [Revised: 03/08/2012] [Accepted: 03/11/2012] [Indexed: 05/31/2023]
Abstract
Chicken natural killer (NK) cells are not well defined, so little is known about the molecular interactions controlling their activity. At day 14 of embryonic development, chick spleens are a rich source of T-cell-free CD8αα(+), CD3(-) cells with natural killing activity. Cell-mediated cytotoxicity assays revealed complex NK cell discrimination of MHC class I, suggesting the presence of multiple NK cell receptors. Immunophenotyping of freshly isolated and recombinant chicken interleukin-2-stimulated d14E CD8αα(+) CD3(-) splenocytes provided further evidence for population heterogeneity. Complex patterns of expression were found for CD8α, chB6 (Bu-1), CD1-1, CD56 (NCAM), KUL01, CD5, and CD44. Mass spectrometry-based proteomics revealed an array of NK cell proteins, including the NKR2B4 receptor. DAVID and KEGG analyses and additional immunophenotyping revealed NK cell activation pathways and evidence for monocytes within the splenocyte cultures. This study provides an underpinning for further investigation into the specificity and function of NK cells in birds.
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Affiliation(s)
- Lei Zhang
- Department of Molecular and Cellular Biology, Beckman Research Institute, City of Hope, Duarte, CA 91010-3000, USA
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