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Minias P. Evolutionary variation in gene conversion at the avian MHC is explained by fluctuating selection, gene copy numbers and life history. Mol Ecol 2024; 33:e17453. [PMID: 38953291 DOI: 10.1111/mec.17453] [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: 01/08/2024] [Revised: 06/05/2024] [Accepted: 06/14/2024] [Indexed: 07/03/2024]
Abstract
The major histocompatibility complex (MHC) multigene family encodes key pathogen-recognition molecules of the vertebrate adaptive immune system. Hyper-polymorphism of MHC genes is de novo generated by point mutations, but new haplotypes may also arise by re-shuffling of existing variation through intra- and inter-locus gene conversion. Although the occurrence of gene conversion at the MHC has been known for decades, we still have limited understanding of its functional importance. Here, I took advantage of extensive genetic resources (~9000 sequences) to investigate broad scale macroevolutionary patterns in gene conversion processes at the MHC across nearly 200 avian species. Gene conversion was found to constitute a universal mechanism in birds, as 83% of species showed footprints of gene conversion at either MHC class and 25% of all allelic variants were attributed to gene conversion. Gene conversion processes were stronger at MHC-II than MHC-I, but inter-specific variation at both MHC classes was explained by similar evolutionary scenarios, reflecting fluctuating selection towards different optima and drift. Gene conversion showed uneven phylogenetic distribution across birds and was driven by gene copy number variation, supporting significant role of inter-locus gene conversion processes in the evolution of the avian MHC. Finally, MHC gene conversion was stronger in species with fast life histories (high fecundity) and in long-distance migrants, likely reflecting variation in population sizes and host-pathogen coevolutionary dynamics. The results provide a robust comparative framework for understanding macroevolutionary variation in gene conversion at the avian MHC and reinforce important contribution of this mechanism to functional MHC diversity.
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Affiliation(s)
- Piotr Minias
- Department of Biodiversity Studies and Bioeducation, Faculty of Biology and Environmental Protection, University of Lodz, Lodz, Poland
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2
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Selection and demography drive range-wide patterns of MHC-DRB variation in mule deer. BMC Ecol Evol 2022; 22:42. [PMID: 35387584 PMCID: PMC8988406 DOI: 10.1186/s12862-022-01998-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Accepted: 03/14/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Standing genetic variation is important especially in immune response-related genes because of threats to wild populations like the emergence of novel pathogens. Genetic variation at the major histocompatibility complex (MHC), which is crucial in activating the adaptive immune response, is influenced by both natural selection and historical population demography, and their relative roles can be difficult to disentangle. To provide insight into the influences of natural selection and demography on MHC evolution in large populations, we analyzed geographic patterns of variation at the MHC class II DRB exon 2 locus in mule deer (Odocoileus hemionus) using sequence data collected across their entire broad range. RESULTS We identified 31 new MHC-DRB alleles which were phylogenetically similar to other cervid MHC alleles, and one allele that was shared with white-tailed deer (Odocoileus virginianus). We found evidence for selection on the MHC including high dN/dS ratios, positive neutrality tests, deviations from Hardy-Weinberg Equilibrium (HWE) and a stronger pattern of isolation-by-distance (IBD) than expected under neutrality. Historical demography also shaped variation at the MHC, as indicated by similar spatial patterns of variation between MHC and microsatellite loci and a lack of association between genetic variation at either locus type and environmental variables. CONCLUSIONS Our results show that both natural selection and historical demography are important drivers in the evolution of the MHC in mule deer and work together to shape functional variation and the evolution of the adaptive immune response in large, well-connected populations.
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3
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Baril T, Hayward A. Migrators within migrators: exploring transposable element dynamics in the monarch butterfly, Danaus plexippus. Mob DNA 2022; 13:5. [PMID: 35172896 PMCID: PMC8848866 DOI: 10.1186/s13100-022-00263-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Accepted: 02/06/2022] [Indexed: 01/10/2023] Open
Abstract
BACKGROUND Lepidoptera (butterflies and moths) are an important model system in ecology and evolution. A high-quality chromosomal genome assembly is available for the monarch butterfly (Danaus plexippus), but it lacks an in-depth transposable element (TE) annotation, presenting an opportunity to explore monarch TE dynamics and the impact of TEs on shaping the monarch genome. RESULTS We find 6.21% of the monarch genome is comprised of TEs, a reduction of 6.85% compared to the original TE annotation performed on the draft genome assembly. Monarch TE content is low compared to two closely related species with available genomes, Danaus chrysippus (33.97% TE) and Danaus melanippus (11.87% TE). The biggest TE contributions to genome size in the monarch are LINEs and Penelope-like elements, and three newly identified families, r2-hero_dPle (LINE), penelope-1_dPle (Penelope-like), and hase2-1_dPle (SINE), collectively contribute 34.92% of total TE content. We find evidence of recent TE activity, with two novel Tc1 families rapidly expanding over recent timescales (tc1-1_dPle, tc1-2_dPle). LINE fragments show signatures of genomic deletions indicating a high rate of TE turnover. We investigate associations between TEs and wing colouration and immune genes and identify a three-fold increase in TE content around immune genes compared to other host genes. CONCLUSIONS We provide a detailed TE annotation and analysis for the monarch genome, revealing a considerably smaller TE contribution to genome content compared to two closely related Danaus species with available genome assemblies. We identify highly successful novel DNA TE families rapidly expanding over recent timescales, and ongoing signatures of both TE expansion and removal highlight the dynamic nature of repeat content in the monarch genome. Our findings also suggest that insect immune genes are promising candidates for future interrogation of TE-mediated host adaptation.
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Affiliation(s)
- Tobias Baril
- Centre for Ecology and Conservation, University of Exeter, Penryn Campus, Penryn, Cornwall, TR10 9FE, UK.
| | - Alexander Hayward
- Centre for Ecology and Conservation, University of Exeter, Penryn Campus, Penryn, Cornwall, TR10 9FE, UK.
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4
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Martin KR, Mansfield KL, Savage AE. Adaptive evolution of major histocompatibility complex class I immune genes and disease associations in coastal juvenile sea turtles. ROYAL SOCIETY OPEN SCIENCE 2022; 9:211190. [PMID: 35154791 PMCID: PMC8825991 DOI: 10.1098/rsos.211190] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Accepted: 01/06/2022] [Indexed: 05/12/2023]
Abstract
Characterizing polymorphism at the major histocompatibility complex (MHC) genes is key to understanding the vertebrate immune response to disease. Despite being globally afflicted by the infectious tumour disease fibropapillomatosis (FP), immunogenetic variation in sea turtles is minimally explored. We sequenced the α 1 peptide-binding region of MHC class I genes (162 bp) from 268 juvenile green (Chelonia mydas) and 88 loggerhead (Caretta caretta) sea turtles in Florida, USA. We recovered extensive variation (116 alleles) and trans-species polymorphism. Supertyping analysis uncovered three functional MHC supertypes corresponding to the three well-supported clades in the phylogeny. We found significant evidence of positive selection at seven amino acid sites in the class I exon. Random forest modelling and risk ratio analysis of Ch. mydas alleles uncovered one allele weakly associated with smooth FP tumour texture, which may be associated with disease outcome. Our study represents the first characterization of MHC class I diversity in Ch. mydas and the largest sample of sea turtles used to date in any study of adaptive genetic variation, revealing tremendous genetic variation and high adaptive potential to viral pathogen threats. The novel associations we identified between MHC diversity and FP outcomes in sea turtles further highlight the importance of evaluating genetic predictors of disease, including MHC and other functional markers.
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Affiliation(s)
- Katherine R. Martin
- Department of Biology, University of Central Florida, 4110 Libra Drive, Orlando, FL 32816, USA
| | - Katherine L. Mansfield
- Department of Biology, University of Central Florida, 4110 Libra Drive, Orlando, FL 32816, USA
| | - Anna E. Savage
- Department of Biology, University of Central Florida, 4110 Libra Drive, Orlando, FL 32816, USA
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5
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Minias P, Drzewińska-Chańko J, Włodarczyk R. Evolution of innate and adaptive immune genes in a non-model waterbird, the common tern. INFECTION GENETICS AND EVOLUTION 2021; 95:105069. [PMID: 34487864 DOI: 10.1016/j.meegid.2021.105069] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2021] [Revised: 08/28/2021] [Accepted: 09/01/2021] [Indexed: 11/25/2022]
Abstract
Toll-like receptors (TLRs) and the Major Histocompatibility Complex (MHC) are the key pathogen-recognition genes of vertebrate immune system and they have a crucial role in the initiation of innate and adaptive immune response, respectively. Recent advancements in sequencing technology sparked research on highly duplicated MHC genes in non-model species, but TLR variation in natural vertebrate populations has remained little studied and comparisons of polymorphism across both TLRs and MHC are scarce. Here, we aimed to compare variation across innate (four TLR loci) and adaptive (MHC class I and class II) immune genes in a non-model avian species, the common tern Sterna hirundo. We detected relatively high allelic richness at TLR genes (9-48 alleles per locus), which was similar to or even higher than the estimated per locus allelic richness at the MHC (24-30 alleles at class I and 13-16 alleles at class II under uniform sample sizes). Despite this, the total number of MHC alleles across all duplicated loci (four class I and three class II) was much higher and MHC alleles showed greater sequence divergence than TLRs. Positive selection targeted relatively more sites at the MHC than TLRs, but the strength of selection (dN/dS ratios) at TLRs was higher when compared to MHC class I. There were also differences in the signature of positive selection and recombination (gene conversion) between MHC class I and II (stronger signature at class II), suggesting that mechanisms maintaining variation at the MHC may vary between both classes. Our study indicates that allelic richness of both innate and adaptive immune receptors may be maintained at relatively high levels in viable avian populations and we recommend a transition from the traditional gene-specific to multi-gene approach in studying molecular evolution of vertebrate immune system.
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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.
| | - Joanna Drzewińska-Chańko
- Department of Biodiversity Studies and Bioeducation, Faculty of Biology and Environmental Protection, University of Łódź, Banacha 1/3, 90-237 Łódź, Poland
| | - Radosław Włodarczyk
- Department of Biodiversity Studies and Bioeducation, Faculty of Biology and Environmental Protection, University of Łódź, Banacha 1/3, 90-237 Łódź, Poland
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6
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Qin S, Dunn PO, Yang Y, Liu H, He K. Polymorphism and varying selection within the MHC class I of four Anas species. Immunogenetics 2021; 73:395-404. [PMID: 34195858 DOI: 10.1007/s00251-021-01222-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Accepted: 06/23/2021] [Indexed: 10/21/2022]
Abstract
Ducks (Anatidae) are often vectors for the spread of pathogens because of their long-distance migrations. These migrations also expose ducks to a wide variety of pathogens in their wintering and breeding grounds, and, as a consequence, we might expect strong selection on their immune genes. Here, we studied exons 2 and 3 of the MHC class I in four species of Anas ducks (A. platyrhynchos, A. poecilorhyncha, A. formosa, and A. querquedula) using Illumina-sequencing. Both exons 2 and 3 code for the peptide-binding region of class I molecules; however, most previous studies of birds have only focused on exon 3. Here, we found stronger positive selection on exon 2 than exon 3, as indicated by more species with dN/dS > 1 and higher Wu-Kabat values. There was little evidence that divergence time influenced polymorphism, the numbers of identical alleles (partial α1 or α2 regions) among four Anas, or selection, suggesting that these widespread species might share similar levels of selection from pathogens. The high similarity of allele numbers, positively selected sites (PSS), conserved motifs, and variable protein sites (VPS) supported the persistence of trans-species polymorphism in Anas for at least 10 million years. Our study revealed exon 2 as a relatively unexplored source of variation in avian MHC class I, which should be considered in future studies.
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Affiliation(s)
- Shidi Qin
- College of Animal Science and Technology, College of Veterinary Medicine, Key Laboratory of Applied Technology On Green-Eco-Healthy Animal Husbandry of Zhejiang Province, Zhejiang Agriculture and Forestry University, Zhejiang Provincial Engineering Laboratory for Animal Health Inspection and Internet Technology, Hangzhou, China
| | - Peter O Dunn
- Behavioral and Molecular Ecology Group, Department of Biological Sciences, University of Wisconsin-Milwaukee, Milwaukee, USA
| | - Yang Yang
- College of Animal Science and Technology, College of Veterinary Medicine, Key Laboratory of Applied Technology On Green-Eco-Healthy Animal Husbandry of Zhejiang Province, Zhejiang Agriculture and Forestry University, Zhejiang Provincial Engineering Laboratory for Animal Health Inspection and Internet Technology, Hangzhou, China
| | - Hongyi Liu
- College of Biology and the Environment, Nanjing Forestry University, Nanjing, 210037, China
| | - Ke He
- College of Animal Science and Technology, College of Veterinary Medicine, Key Laboratory of Applied Technology On Green-Eco-Healthy Animal Husbandry of Zhejiang Province, Zhejiang Agriculture and Forestry University, Zhejiang Provincial Engineering Laboratory for Animal Health Inspection and Internet Technology, Hangzhou, China.
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7
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Minias P, Włodarczyk R, Remisiewicz M, Cobzaru I, Janiszewski T. Distinct evolutionary trajectories of MHC class I and class II genes in Old World finches and buntings. Heredity (Edinb) 2021; 126:974-990. [PMID: 33824536 PMCID: PMC8178356 DOI: 10.1038/s41437-021-00427-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 03/08/2021] [Accepted: 03/15/2021] [Indexed: 02/01/2023] Open
Abstract
Major histocompatibility complex (MHC) genes code for key proteins of the adaptive immune system, which present antigens from intra-cellular (MHC class I) and extra-cellular (MHC class II) pathogens. Because of their unprecedented diversity, MHC genes have long been an object of scientific interest, but due to methodological difficulties in genotyping of duplicated loci, our knowledge on the evolution of the MHC across different vertebrate lineages is still limited. Here, we compared the evolution of MHC class I and class II genes in three sister clades of common passerine birds, finches (Fringillinae and Carduelinae) and buntings (Emberizidae) using a uniform methodological (genotyping and data processing) approach and uniform sample sizes. Our analyses revealed contrasting evolutionary trajectories of the two MHC classes. We found a stronger signature of pervasive positive selection and higher allele diversity (allele numbers) at the MHC class I than class II. In contrast, MHC class II genes showed greater allele divergence (in terms of nucleotide diversity) and a much stronger recombination (gene conversion) signal. Gene copy numbers at both MHC class I and class II evolved via fluctuating selection and drift (Brownian Motion evolution), but the evolutionary rate was higher at class I. Our study constitutes one of few existing examples, where evolution of MHC class I and class II genes was directly compared using a multi-species approach. We recommend that re-focusing MHC research from single-species and single-class approaches towards multi-species analyses of both MHC classes can substantially increase our understanding MHC evolution in a broad phylogenetic context.
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Affiliation(s)
- Piotr Minias
- Department of Biodiversity Studies and Bioeducation, Faculty of Biology and Environmental Protection, University of Łódź, Łódź, Poland.
| | - Radosław Włodarczyk
- Department of Biodiversity Studies and Bioeducation, Faculty of Biology and Environmental Protection, University of Łódź, Łódź, Poland
| | - Magdalena Remisiewicz
- Bird Migration Research Station, Faculty of Biology, University of Gdańsk, Gdańsk, Poland
| | - Ioana Cobzaru
- Institute of Biology Bucharest, Romanian Academy, Bucharest, Romania
| | - Tomasz Janiszewski
- Department of Biodiversity Studies and Bioeducation, Faculty of Biology and Environmental Protection, University of Łódź, Łódź, Poland
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8
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Ghani MU, Bo L, Buyang A, Yanchun X, Hussain S, Yasir M. Molecular Characterization of MHC Class I Genes in Four Species of the Turdidae Family to Assess Genetic Diversity and Selection. BIOMED RESEARCH INTERNATIONAL 2021; 2021:5585687. [PMID: 33937397 PMCID: PMC8055405 DOI: 10.1155/2021/5585687] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Revised: 03/09/2021] [Accepted: 03/19/2021] [Indexed: 11/17/2022]
Abstract
In vertebrate animals, the molecules encoded by major histocompatibility complex (MHC) genes play an essential role in the adaptive immunity. MHC class I deals with intracellular pathogens (virus) in birds. MHC class I diversity depends on the consequence of local and global environment selective pressure and gene flow. Here, we evaluated the MHC class I gene in four species of the Turdidae family from a broad geographical area of northeast China. We isolated 77 MHC class I sequences, including 47 putatively functional sequences and 30 pseudosequences from 80 individuals. Using the method based on analysis of cloned amplicons (n = 25) for each species, we found two and seven MHC I sequences per individual indicating more than one MHC I locus identified in all sampled species. Results revealed an overall elevated genetic diversity at MHC class I, evidence of different selection patterns among the domains of PBR and non-PBR. Alleles are found to be divergent with overall polymorphic sites per species ranging between 58 and 70 (out of 291 sites). Moreover, transspecies alleles were evident due to convergent evolution or recent speciation for the genus. Phylogenetic relationships among MHC I show an intermingling of alleles clustering among the Turdidae family rather than between other passerines. Pronounced MHC I gene diversity is essential for the existence of species. Our study signifies a valuable tool for the characterization of evolutionary relevant difference across a population of birds with high conservational concerns.
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Affiliation(s)
- Muhammad Usman Ghani
- College of Wildlife Resources and Protected Area, Northeast Forestry University, Harbin 150040, China
| | - Li Bo
- College of Wildlife Resources and Protected Area, Northeast Forestry University, Harbin 150040, China
| | - An Buyang
- Department of Stem Cell Biology and Medicine, Graduate School of Medical Science, Kyushu University, Fukuoka 810-0000, Japan
| | - Xu Yanchun
- College of Wildlife Resources and Protected Area, Northeast Forestry University, Harbin 150040, China
| | - Shakeel Hussain
- College of Wildlife Resources and Protected Area, Northeast Forestry University, Harbin 150040, China
| | - Muhammad Yasir
- Department of Life Science and Technology, Huazhong Agricultural University, Wuhan, China
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9
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Li X, Liu T, Li A, Zhang L, Dai W, Jin L, Sun K, Feng J. Genetic polymorphisms and the independent evolution of major histocompatibility complex class II‐
DRB
in sibling bat species
Rhinolophus episcopus
and
Rhinolophus siamensis. J ZOOL SYST EVOL RES 2021. [DOI: 10.1111/jzs.12462] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Xiaolin Li
- Jilin Provincial Key Laboratory of Animal Resource Conservation and Utilization Northeast Normal University Changchun China
| | - Tong Liu
- Jilin Provincial Key Laboratory of Animal Resource Conservation and Utilization Northeast Normal University Changchun China
| | - Aoqiang Li
- Jilin Provincial Key Laboratory of Animal Resource Conservation and Utilization Northeast Normal University Changchun China
| | - Lin Zhang
- Jilin Provincial Key Laboratory of Animal Resource Conservation and Utilization Northeast Normal University Changchun China
| | - Wentao Dai
- Jilin Provincial Key Laboratory of Animal Resource Conservation and Utilization Northeast Normal University Changchun China
| | - Longru Jin
- Jilin Provincial Key Laboratory of Animal Resource Conservation and Utilization Northeast Normal University Changchun China
| | - Keping Sun
- Jilin Provincial Key Laboratory of Animal Resource Conservation and Utilization Northeast Normal University Changchun China
- Key Laboratory of Vegetation Ecology Ministry of Education Changchun China
| | - Jiang Feng
- Jilin Provincial Key Laboratory of Animal Resource Conservation and Utilization Northeast Normal University Changchun China
- College of Life Science Jilin Agricultural University Changchun China
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10
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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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11
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Stervander M, Dierickx EG, Thorley J, Brooke MDL, Westerdahl H. High MHC gene copy number maintains diversity despite homozygosity in a Critically Endangered single-island endemic bird, but no evidence of MHC-based mate choice. Mol Ecol 2020; 29:3578-3592. [PMID: 32416000 DOI: 10.1111/mec.15471] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Revised: 04/14/2020] [Accepted: 05/04/2020] [Indexed: 12/30/2022]
Abstract
Small population sizes can, over time, put species at risk due to the loss of genetic variation and the deleterious effects of inbreeding. Losing diversity in the major histocompatibility complex (MHC) could be particularly harmful, given its key role in the immune system. Here, we assess MHC class I (MHC-I) diversity and its effects on mate choice and survival in the Critically Endangered Raso lark Alauda razae, a species restricted to the 7 km2 islet of Raso, Cape Verde, since ~1460, whose population size has dropped as low as 20 pairs. Exhaustively genotyping 122 individuals, we find no effect of MHC-I genotype/diversity on mate choice or survival. However, we demonstrate that MHC-I diversity has been maintained through extreme bottlenecks by retention of a high number of gene copies (at least 14), aided by cosegregation of multiple haplotypes comprising 2-8 linked MHC-I loci. Within-locus homozygosity is high, contributing to low population-wide diversity. Conversely, each individual had comparably many alleles, 6-16 (average 11), and the large and divergent haplotypes occur at high frequency in the population, resulting in high within-individual MHC-I diversity. This functional immune gene diversity will be of critical importance for this highly threatened species' adaptive potential.
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Affiliation(s)
- Martin Stervander
- Department of Biology, Lund University, Lund, Sweden.,Department of Biology and Environmental Science, Faculty of Health and Life Sciences, Linnaeus University, Kalmar, Sweden.,Institute of Ecology and Evolution, University of Oregon, Eugene, OR, USA
| | - Elisa G Dierickx
- Department of Zoology, University of Cambridge, Cambridge, UK.,Fauna & Flora International, Cambridge, UK
| | - Jack Thorley
- Department of Zoology, University of Cambridge, Cambridge, UK
| | - M de L Brooke
- Department of Zoology, University of Cambridge, Cambridge, UK
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12
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Zhao B, Zhang X, Li B, Du P, Shi L, Dong Y, Gao X, Sha W, Zhang H. Evolution of major histocompatibility complex class I genes in the sable Martes zibellina (Carnivora, Mustelidae). Ecol Evol 2020; 10:3439-3449. [PMID: 32274000 PMCID: PMC7141072 DOI: 10.1002/ece3.6140] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Revised: 01/31/2020] [Accepted: 02/04/2020] [Indexed: 11/10/2022] Open
Abstract
The molecules encoded by major histocompatibility complex (MHC) genes play an essential role in the adaptive immune response among vertebrates. We investigated the molecular evolution of MHC class I genes in the sable Martes zibellina. We isolated 26 MHC class I sequences, including 12 putatively functional sequences and 14 pseudogene sequences, from 24 individuals from two geographic areas of northeast China. The number of putatively functional sequences found in a single individual ranged from one to five, which might be at least 1-3 loci. We found that both balancing selection and recombination contribute to evolution of MHC class I genes in M. zibellina. In addition, we identified a candidate nonclassical MHC class I lineage in Carnivora, which may have preceded the divergence (about 52-57 Mya) of Caniformia and Feliformia. This may contribute to further understanding of the origin and evolution of nonclassical MHC class I genes. Our study provides important immune information of MHC for M. zibellina, as well as other carnivores.
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Affiliation(s)
- Baojun Zhao
- College of Life Science Qufu Normal University Qufu China
| | - Xue Zhang
- College of Life Science Qufu Normal University Qufu China
| | - Bo Li
- College of Wildlife and Protected Area Northeast Forestry University Harbin China
| | - Pengfei Du
- College of Life Science Qufu Normal University Qufu China
| | - Lupeng Shi
- College of Life Science Qufu Normal University Qufu China
| | - Yuehuan Dong
- College of Life Science Qufu Normal University Qufu China
| | - Xiaodong Gao
- College of Life Science Qufu Normal University Qufu China
| | - Weilai Sha
- College of Life Science Qufu Normal University Qufu China
| | - Honghai Zhang
- College of Life Science Qufu Normal University Qufu China
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13
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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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14
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Minias P, Pikus E, Whittingham LA, Dunn PO. A global analysis of selection at the avian MHC. Evolution 2018; 72:1278-1293. [PMID: 29665025 DOI: 10.1111/evo.13490] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2017] [Revised: 03/29/2018] [Accepted: 04/09/2018] [Indexed: 12/29/2022]
Abstract
Recent advancements in sequencing technology have resulted in rapid progress in the study of the major histocompatibility complex (MHC) in non-model avian species. Here, we analyze a global dataset of avian MHC class I and class II sequences (ca. 11,000 sequences from over 250 species) to gain insight into the processes that govern macroevolution of MHC genes in birds. Analysis of substitution rates revealed striking differences in the patterns of diversifying selection between passerine and non-passerine birds. Non-passerines showed stronger selection at MHC class II, which is primarily involved in recognition of extracellular pathogens, while passerines showed stronger selection at MHC class I, which is involved in recognition of intracellular pathogens. Positions of positively selected amino-acid residues showed marked discrepancies with peptide-binding residues (PBRs) of human MHC molecules, suggesting that using a human classification of PBRs to assess selection patterns at the avian MHC may be unjustified. Finally, our analysis provided evidence that indel mutations can make a substantial contribution to adaptive variation at the avian MHC.
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Affiliation(s)
- Piotr Minias
- Department of Biodiversity Studies and Bioeducation, Faculty of Biology and Environmental Protection, University of Łódź, Łódź, 90-237, Poland
| | - Ewa Pikus
- Department of Biodiversity Studies and Bioeducation, Faculty of Biology and Environmental Protection, University of Łódź, Łódź, 90-237, Poland
| | - Linda A Whittingham
- Behavioral and Molecular Ecology Group, Department of Biological Sciences, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin, 53211
| | - Peter O Dunn
- Department of Biodiversity Studies and Bioeducation, Faculty of Biology and Environmental Protection, University of Łódź, Łódź, 90-237, Poland.,Behavioral and Molecular Ecology Group, Department of Biological Sciences, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin, 53211
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15
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Minias P, Bateson ZW, Whittingham LA, Johnson JA, Oyler-McCance S, Dunn PO. Extensive shared polymorphism at non-MHC immune genes in recently diverged North American prairie grouse. Immunogenetics 2017; 70:195-204. [PMID: 28770305 PMCID: PMC5818594 DOI: 10.1007/s00251-017-1024-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Accepted: 07/25/2017] [Indexed: 12/23/2022]
Abstract
Gene polymorphisms shared between recently diverged species are thought to be widespread and most commonly reflect introgression from hybridization or retention of ancestral polymorphism through incomplete lineage sorting. Shared genetic diversity resulting from incomplete lineage sorting is usually maintained for a relatively short period of time, but under strong balancing selection it may persist for millions of years beyond species divergence (balanced trans-species polymorphism), as in the case of the major histocompatibility complex (MHC) genes. However, balancing selection is much less likely to act on non-MHC immune genes. The aim of this study was to investigate the patterns of shared polymorphism and selection at non-MHC immune genes in five grouse species from Centrocercus and Tympanuchus genera. For this purpose, we genotyped five non-MHC immune genes that do not interact directly with pathogens, but are involved in signaling and regulate immune cell growth. In contrast to previous studies with MHC, we found no evidence for balancing selection or balanced trans-species polymorphism among the non-MHC immune genes. No haplotypes were shared between genera and in most cases more similar allelic variants sorted by genus. Between species within genera, however, we found extensive shared polymorphism, which was most likely attributable to introgression or incomplete lineage sorting following recent divergence and large ancestral effective population size (i.e., weak genetic drift). Our study suggests that North American prairie grouse may have attained relatively low degree of reciprocal monophyly at nuclear loci and reinforces the rarity of balancing selection in non-MHC immune genes.
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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.
| | - Zachary W Bateson
- Behavioral and Molecular Ecology Group, Department of Biological Sciences, University of Wisconsin-Milwaukee, Milwaukee, WI, USA
| | - Linda A Whittingham
- Behavioral and Molecular Ecology Group, Department of Biological Sciences, University of Wisconsin-Milwaukee, Milwaukee, WI, USA
| | - Jeff A Johnson
- Department of Biological Sciences, Institute of Applied Sciences, University of North Texas, Denton, TX, USA
| | | | - Peter O Dunn
- Behavioral and Molecular Ecology Group, Department of Biological Sciences, University of Wisconsin-Milwaukee, Milwaukee, WI, USA
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16
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Razali H, O'Connor E, Drews A, Burke T, Westerdahl H. A quantitative and qualitative comparison of illumina MiSeq and 454 amplicon sequencing for genotyping the highly polymorphic major histocompatibility complex (MHC) in a non-model species. BMC Res Notes 2017; 10:346. [PMID: 28754172 PMCID: PMC5534077 DOI: 10.1186/s13104-017-2654-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2016] [Accepted: 07/21/2017] [Indexed: 11/24/2022] Open
Abstract
Background High-throughput sequencing enables high-resolution genotyping of extremely duplicated genes. 454 amplicon sequencing (454) has become the standard technique for genotyping the major histocompatibility complex (MHC) genes in non-model organisms. However, illumina MiSeq amplicon sequencing (MiSeq), which offers a much higher read depth, is now superseding 454. The aim of this study was to quantitatively and qualitatively evaluate the performance of MiSeq in relation to 454 for genotyping MHC class I alleles using a house sparrow (Passer domesticus) dataset with pedigree information. House sparrows provide a good study system for this comparison as their MHC class I genes have been studied previously and, consequently, we had prior expectations concerning the number of alleles per individual. Results We found that 454 and MiSeq performed equally well in genotyping amplicons with low diversity, i.e. amplicons from individuals that had fewer than 6 alleles. Although there was a higher rate of failure in the 454 dataset in resolving amplicons with higher diversity (6–9 alleles), the same genotypes were identified by both 454 and MiSeq in 98% of cases. Conclusions We conclude that low diversity amplicons are equally well genotyped using either 454 or MiSeq, but the higher coverage afforded by MiSeq can lead to this approach outperforming 454 in amplicons with higher diversity. Electronic supplementary material The online version of this article (doi:10.1186/s13104-017-2654-1) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Haslina Razali
- Department of Animal and Plant Sciences, University of Sheffield, Sheffield, S10 2TN, UK
| | - Emily O'Connor
- Molecular Ecology and Evolution Lab, Department of Biology, Lund University, Sölvegatan 37, 223 62, Lund, Sweden.
| | - Anna Drews
- Molecular Ecology and Evolution Lab, Department of Biology, Lund University, Sölvegatan 37, 223 62, Lund, Sweden
| | - Terry Burke
- Department of Animal and Plant Sciences, University of Sheffield, Sheffield, S10 2TN, UK
| | - Helena Westerdahl
- Molecular Ecology and Evolution Lab, Department of Biology, Lund University, Sölvegatan 37, 223 62, Lund, Sweden
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17
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Abduriyim S, Nishita Y, Kosintsev PA, Raichev E, Väinölä R, Kryukov AP, Abramov AV, Kaneko Y, Masuda R. Diversity and evolution of MHC class II DRB gene in the Eurasian badger genus Meles (Mammalia: Mustelidae). Biol J Linn Soc Lond 2017. [DOI: 10.1093/biolinnean/blx077] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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18
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Gillingham MAF, Béchet A, Courtiol A, Rendón-Martos M, Amat JA, Samraoui B, Onmuş O, Sommer S, Cézilly F. Very high MHC Class IIB diversity without spatial differentiation in the mediterranean population of greater Flamingos. BMC Evol Biol 2017; 17:56. [PMID: 28219340 PMCID: PMC5319168 DOI: 10.1186/s12862-017-0905-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Accepted: 02/06/2017] [Indexed: 02/07/2023] Open
Abstract
Background Selective pressure from pathogens is thought to shape the allelic diversity of major histocompatibility complex (MHC) genes in vertebrates. In particular, both local adaptation to pathogens and gene flow are thought to explain a large part of the intraspecific variation observed in MHC allelic diversity. To date, however, evidence that adaptation to locally prevalent pathogens maintains MHC variation is limited to species with limited dispersal and, hence, reduced gene flow. On the one hand high gene flow can disrupt local adaptation in species with high dispersal rates, on the other hand such species are much more likely to experience spatial variation in pathogen pressure, suggesting that there may be intense pathogen mediated selection pressure operating across breeding sites in panmictic species. Such pathogen mediated selection pressure operating across breeding sites should therefore be sufficient to maintain high MHC diversity in high dispersing species in the absence of local adaptation mechanisms. We used the Greater Flamingo, Phoenicopterus roseus, a long-lived colonial bird showing a homogeneous genetic structure of neutral markers at the scale of the Mediterranean region, to test the prediction that higher MHC allelic diversity with no population structure should occur in large panmictic populations of long-distance dispersing birds than in other resident species. Results We assessed the level of allelic diversity at the MHC Class IIB exon 2 from 116 individuals born in four different breeding colonies of Greater Flamingo in the Mediterranean region. We found one of the highest allelic diversity (109 alleles, 2 loci) of any non-passerine avian species investigated so far relative to the number of individuals and loci genotyped. There was no evidence of population structure between the four major Mediterranean breeding colonies. Conclusion Our results suggest that local adaptation at MHC Class IIB in Greater Flamingos is constrained by high gene flow and high MHC diversity appears to be maintained by population wide pathogen-mediated selection rather than local pathogen-mediated selection. Further understanding of how pathogens vary across space and time will be crucial to further elucidate the mechanisms maintaining MHC diversity in species with large panmictic populations and high dispersal rates. Electronic supplementary material The online version of this article (doi:10.1186/s12862-017-0905-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Mark A F Gillingham
- University of Ulm, Institute of Evolutionary Ecology and Conservation Genomics, Albert-Einstein Allee 11, D-89069, Ulm, Germany. .,Université de Bourgogne, Equipe Ecologie Evolutive, UMR CNRS 6282 Biogéosciences, 6 bd. Gabriel, 21000, Dijon, France. .,Centre de Recherche de la Tour du Valat, Le Sambuc, 13200, Arles, France. .,Leibniz Institute for Zoo and Wildlife Research, Evolutionary Genetics, Alfred-Kowalke-Str. 17, D-10315, Berlin, Germany.
| | - Arnaud Béchet
- Centre de Recherche de la Tour du Valat, Le Sambuc, 13200, Arles, France
| | - Alexandre Courtiol
- Leibniz Institute for Zoo and Wildlife Research, Evolutionary Genetics, Alfred-Kowalke-Str. 17, D-10315, Berlin, Germany.,Berlin Center for Genomics in Biodiversity Research (BeGenDiv), D-14195, Berlin, Germany
| | - Manuel Rendón-Martos
- R.N. Laguna de Fuente de Piedra, Consejería de Medio Ambiente y Ordenación del Territorio, Junta de Andalucía, Apartado 1, E-29520 Fuente de Piedra, (Málaga), Spain
| | - Juan A Amat
- Department of Wetland Ecology, Estación Biológica de Doñana, (EBD-CSIC), calle Américo Vespucio s/n, E-41092, Sevilla, Spain
| | - Boudjéma Samraoui
- Center of Excellence for Research in Biodiversity, King Saud University, Riyadh, Saudi Arabia.,Laboratoire de recherche et de conservation des zones humides, University of Guelma, Guelma, Algeria
| | - Ortaç Onmuş
- Natural History Museum, Faculty of Sciences, Department of Biology, Ege University, Bornova, İzmir, Turkey
| | - Simone Sommer
- University of Ulm, Institute of Evolutionary Ecology and Conservation Genomics, Albert-Einstein Allee 11, D-89069, Ulm, Germany
| | - Frank Cézilly
- Université de Bourgogne, Equipe Ecologie Evolutive, UMR CNRS 6282 Biogéosciences, 6 bd. Gabriel, 21000, Dijon, France.,Institut Universitaire de France, Paris, France
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19
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Polymorphism at expressed DQ and DR loci in five common equine MHC haplotypes. Immunogenetics 2016; 69:145-156. [PMID: 27889800 DOI: 10.1007/s00251-016-0964-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2016] [Accepted: 11/19/2016] [Indexed: 12/16/2022]
Abstract
The polymorphism of major histocompatibility complex (MHC) class II DQ and DR genes in five common equine leukocyte antigen (ELA) haplotypes was determined through sequencing of mRNA transcripts isolated from lymphocytes of eight ELA homozygous horses. Ten expressed MHC class II genes were detected in horses of the ELA-A3 haplotype carried by the donor horses of the equine bacterial artificial chromosome (BAC) library and the reference genome sequence: four DR genes and six DQ genes. The other four ELA haplotypes contained at least eight expressed polymorphic MHC class II loci. Next generation sequencing (NGS) of genomic DNA of these four MHC haplotypes revealed stop codons in the DQA3 gene in the ELA-A2, ELA-A5, and ELA-A9 haplotypes. Few NGS reads were obtained for the other MHC class II genes that were not amplified in these horses. The amino acid sequences across haplotypes contained locus-specific residues, and the locus clusters produced by phylogenetic analysis were well supported. The MHC class II alleles within the five tested haplotypes were largely non-overlapping between haplotypes. The complement of equine MHC class II DQ and DR genes appears to be well conserved between haplotypes, in contrast to the recently described variation in class I gene loci between equine MHC haplotypes. The identification of allelic series of equine MHC class II loci will aid comparative studies of mammalian MHC conservation and evolution and may also help to interpret associations between the equine MHC class II region and diseases of the horse.
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20
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Bateson ZW, Hammerly SC, Johnson JA, Morrow ME, Whittingham LA, Dunn PO. Specific alleles at immune genes, rather than genome‐wide heterozygosity, are related to immunity and survival in the critically endangered Attwater's prairie‐chicken. Mol Ecol 2016; 25:4730-44. [DOI: 10.1111/mec.13793] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2016] [Revised: 07/17/2016] [Accepted: 07/19/2016] [Indexed: 12/20/2022]
Affiliation(s)
- Zachary W. Bateson
- Behavioral and Molecular Ecology Group Department of Biological Sciences University of Wisconsin‐Milwaukee PO Box 413 Milwaukee WI 53201 USA
| | - Susan C. Hammerly
- Department of Biological Sciences Institute of Applied Sciences University of North Texas 1155 Union Circle Denton TX 76203 USA
| | - Jeff A. Johnson
- Department of Biological Sciences Institute of Applied Sciences University of North Texas 1155 Union Circle Denton TX 76203 USA
| | - Michael E. Morrow
- Attwater Prairie Chicken National Wildlife Refuge PO Box 519 Eagle Lake TX 77434 USA
| | - Linda A. Whittingham
- Behavioral and Molecular Ecology Group Department of Biological Sciences University of Wisconsin‐Milwaukee PO Box 413 Milwaukee WI 53201 USA
| | - Peter O. Dunn
- Behavioral and Molecular Ecology Group Department of Biological Sciences University of Wisconsin‐Milwaukee PO Box 413 Milwaukee WI 53201 USA
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