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Yan J, Song C, Liang J, La Y, Lai J, Pan R, Huang Z, Li B, Zhang P. Moderate Genetic Diversity of MHC Genes in an Isolated Small Population of Black-and-White Snub-Nosed Monkeys ( Rhinopithecus bieti). Animals (Basel) 2024; 14:2276. [PMID: 39123802 PMCID: PMC11310952 DOI: 10.3390/ani14152276] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2024] [Revised: 08/01/2024] [Accepted: 08/01/2024] [Indexed: 08/12/2024] Open
Abstract
Genetic diversity is an essential indicator that echoes the natural selection and environmental adaptation of a species. Isolated small populations are vulnerable to genetic drift, inbreeding, and limited gene flow; thus, assessing their genetic diversity is critical in conservation. In this study, we studied the genetic diversity of black-and-white snub-nosed monkeys (Rhinopithecus bieti) using neutral microsatellites and five adaptive major histocompatibility complex (MHC) genes. Two DQA1 alleles, two DQB1 alleles, two DRB1 alleles, two DRB5 alleles, and three DPB1 alleles were isolated from a population. The results indicate that neutral microsatellites demonstrate a high degree of heterozygosity and polymorphism, while adaptive MHC genes display a high degree of heterozygosity and moderate polymorphism. The results also show that balancing selection has prominently influenced the MHC diversity of the species during evolution: (1) significant positive selection is identified at several amino acid sites (primarily at and near antigen-binding sites) of the DRB1, DRB5, and DQB1 genes; (2) phylogenetic analyses display the patterns of trans-species evolution for all MHC loci. This study provides valuable genetic diversity insights into black-and-white snub-nosed monkeys, which dwell at the highest altitude and have experienced the harshest environmental selection of all primates globally since the Pleistocene. Such results provide valuable scientific evidence and a reference for making or amending conservation strategies for this endangered primate species.
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Affiliation(s)
- Jibing Yan
- Shaanxi Key Laboratory of Animal Conservation, College of Life Sciences, Northwest University, Xi’an 710069, China; (J.Y.); (C.S.); (J.L.); (Y.L.); (R.P.)
| | - Chunmei Song
- Shaanxi Key Laboratory of Animal Conservation, College of Life Sciences, Northwest University, Xi’an 710069, China; (J.Y.); (C.S.); (J.L.); (Y.L.); (R.P.)
| | - Jiaqi Liang
- Shaanxi Key Laboratory of Animal Conservation, College of Life Sciences, Northwest University, Xi’an 710069, China; (J.Y.); (C.S.); (J.L.); (Y.L.); (R.P.)
| | - Yanni La
- Shaanxi Key Laboratory of Animal Conservation, College of Life Sciences, Northwest University, Xi’an 710069, China; (J.Y.); (C.S.); (J.L.); (Y.L.); (R.P.)
| | - Jiandong Lai
- Baima Snow Mountain National Nature Reserve Administrative Bureau, Diqing 674500, China;
| | - Ruliang Pan
- Shaanxi Key Laboratory of Animal Conservation, College of Life Sciences, Northwest University, Xi’an 710069, China; (J.Y.); (C.S.); (J.L.); (Y.L.); (R.P.)
- International Center of Biodiversity and Primat Conservation, Dali University, Dali 671003, China
- School of Human Sciences, The University of Western Australia, Perth, WA 6009, Australia
| | - Zhipang Huang
- Institute of Eastern-Himalaya Biodiversity Research, Dali University, Dali 671003, China;
| | - Baoguo Li
- Shaanxi Key Laboratory of Animal Conservation, College of Life Sciences, Northwest University, Xi’an 710069, China; (J.Y.); (C.S.); (J.L.); (Y.L.); (R.P.)
- Shaanxi Institute of Zoology, Xi’an 710032, China
- College of Life Science, Yanan University, Yanan 710032, China
| | - Pei Zhang
- Shaanxi Key Laboratory of Animal Conservation, College of Life Sciences, Northwest University, Xi’an 710069, China; (J.Y.); (C.S.); (J.L.); (Y.L.); (R.P.)
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Minias P, Pap PL, Vincze O, Vágási CI. Correlated evolution of oxidative physiology and MHC-based immunosurveillance in birds. Proc Biol Sci 2024; 291:20240686. [PMID: 38889785 DOI: 10.1098/rspb.2024.0686] [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: 01/12/2024] [Accepted: 05/06/2024] [Indexed: 06/20/2024] Open
Abstract
Maintenance and activation of the immune system incur costs, not only in terms of substrates and energy but also via collateral oxidative damage to host cells or tissues during immune response. So far, associations between immune function and oxidative damage have been primarily investigated at intra-specific scales. Here, we hypothesized that pathogen-driven selection should favour the evolution of effective immunosurveillance mechanisms (e.g. major histocompatibility complex, MHC) and antioxidant defences to mitigate oxidative damage resulting from immune function. Using phylogenetically informed comparative approaches, we provided evidence for the correlated evolution of host oxidative physiology and MHC-based immunosurveillance in birds. Species selected for more robust MHC-based immunosurveillance (higher gene copy numbers and allele diversity) showed stronger antioxidant defences, although selection for MHC diversity still showed a positive evolutionary association with oxidative damage to lipids. Our results indicate that historical pathogen-driven selection for highly duplicated and diverse MHC could have promoted the evolution of efficient antioxidant mechanisms, but these evolutionary solutions may be insufficient to keep oxidative stress at bounds. Although the precise nature of mechanistic links between the MHC and oxidative stress remains unclear, our study suggests that a general evolutionary investment in immune function may require co-adaptations at the level of host oxidative metabolism.
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Affiliation(s)
- Piotr Minias
- Department of Biodiversity Studies and Bioeducation, University of Lodz, Faculty of Biology and Environmental Protection, Banacha 1/3, 90-237 Lodz, Poland
| | - Péter L Pap
- Evolutionary Ecology Group, Hungarian Department of Biology and Ecology, Babeş-Bolyai University, Cluj-Napoca, Romania
| | - Orsolya Vincze
- Evolutionary Ecology Group, Hungarian Department of Biology and Ecology, Babeş-Bolyai University, Cluj-Napoca, Romania
- Wetland Ecology Research Group, HUN-REN Centre for Ecological Research, Institute of Aquatic Ecology, Debrecen, Hungary
- ImmunoConcEpT, University of Bordeaux, CNRS UMR 5164, Bordeaux, France
| | - Csongor I Vágási
- Evolutionary Ecology Group, Hungarian Department of Biology and Ecology, Babeş-Bolyai University, Cluj-Napoca, Romania
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He K, Liang C, Ma S, Liu H, Zhu Y. Copy number and selection of MHC genes in ruminants are related to habitat, average life span and diet. Gene 2024; 904:148179. [PMID: 38242373 DOI: 10.1016/j.gene.2024.148179] [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: 09/18/2023] [Revised: 12/26/2023] [Accepted: 01/16/2024] [Indexed: 01/21/2024]
Abstract
The ruminants, as the main group of livestock, have been extensively studied in terms of their physiology, endocrinology, biochemistry, genetics, and nutrition. Despite the wide geographic distribution and habitat diversity of animals in this group, their ecology and evolution remain poorly understood. In this study, we analyzed the gene copy number, selection, and ecological and evolutionary processes that have affected the evolution of major histocompatibility complex (MHC) genes across ruminant lineages based on available genomic data. The 51 species analyzed represented all six families of ruminants. Our finding indicated that the architecture of the MHC region is conserved in ruminants, but with variable copy numbers of MHC-I, MHC-IIA, and MHC-IIB genes. No lineage-specific gene duplication was observed in the MHC genes. The phylogenetic generalized least squares regression (PGLS) model revealed association between ecological and biological factors (habitat and lifespan) and gene duplication in DQA and DQB, but not in DRB. The selection pressure of DQA and DQB were related with lifespan, diet, and the ratio of genetic repeat elements. These results suggest that the MHC evolution in ruminants, including copy number and selection, has been influenced by genetic repeat elements, pathogen exposure risk, and intrinsic cost of possessing multiple MHC genes.
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Affiliation(s)
- Ke He
- College of Animal Science and Technology, College of Veterinary Medicine, Zhejiang Agriculture and Forestry University, Key Laboratory of Applied Technology on Green-Eco-Healthy Animal Husbandry of Zhejiang Province, Hangzhou, China
| | - Chunhong Liang
- College of Animal Science and Technology, College of Veterinary Medicine, Zhejiang Agriculture and Forestry University, Key Laboratory of Applied Technology on Green-Eco-Healthy Animal Husbandry of Zhejiang Province, Hangzhou, China
| | - Shujuan Ma
- Institute of Qinghai-Tibetan Plateau, Southwest Minzu University, Chengdu, China
| | - Hongyi Liu
- College of Biology and the Environment, Nanjing Forestry University, Nanjing, China
| | - Ying Zhu
- Institute of Qinghai-Tibetan Plateau, Southwest Minzu University, Chengdu, China.
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Day G, Robb K, Oxley A, Telonis-Scott M, Ujvari B. Organisation and evolution of the major histocompatibility complex class I genes in cetaceans. iScience 2024; 27:109590. [PMID: 38632986 PMCID: PMC11022044 DOI: 10.1016/j.isci.2024.109590] [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: 04/26/2023] [Revised: 09/30/2023] [Accepted: 03/25/2024] [Indexed: 04/19/2024] Open
Abstract
A quarter of marine mammals are at risk of extinction, with disease and poor habitat quality contributing to population decline. Investigation of the Major Histocompatibility Complex (MHC) provides insight into species' capacity to respond to immune and environmental challenges. The eighteen available cetacean chromosome level genomes were used to annotate MHC Class I loci, and to reconstruct the phylogenetic relationship of the described loci. The highest number of loci was observed in the striped dolphin (Stenella coeruleoalba), while the least was observed in the pygmy sperm whale (Kogia breviceps) and rough toothed dolphin (Steno bredanensis). Of the species studied, Mysticetes had the most pseudogenes. Evolutionarily, MHC Class I diverged before the speciation of cetaceans. Yet, locus one was genomically and phylogenetically similar in many species, persisting over evolutionary time. This characterisation of MHC Class I in cetaceans lays the groundwork for future population genetics and MHC expression studies.
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Affiliation(s)
- Grace Day
- School of Life and Environmental Sciences, Deakin University, Geelong 3216, VIC, Australia
- Marine Mammal Foundation, Melbourne 3194, VIC, Australia
| | - Kate Robb
- Marine Mammal Foundation, Melbourne 3194, VIC, Australia
| | - Andrew Oxley
- School of Life and Environmental Sciences, Deakin University, Geelong 3216, VIC, Australia
| | - Marina Telonis-Scott
- School of Life and Environmental Sciences, Deakin University, Melbourne 3125, VIC, Australia
| | - Beata Ujvari
- School of Life and Environmental Sciences, Deakin University, Geelong 3216, VIC, Australia
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Cortazar-Chinarro M, Richter-Boix A, Rödin-Mörch P, Halvarsson P, Logue JB, Laurila A, Höglund J. Association between the skin microbiome and MHC class II diversity in an amphibian. Mol Ecol 2024; 33:e17198. [PMID: 37933583 DOI: 10.1111/mec.17198] [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: 04/03/2023] [Revised: 10/20/2023] [Accepted: 10/26/2023] [Indexed: 11/08/2023]
Abstract
Microbiomes play an important role in determining the ecology and behaviour of their hosts. However, questions remain pertaining to how host genetics shape microbiomes, and how microbiome composition influences host fitness. We explored the effects of geography, evolutionary history and host genetics on the skin microbiome diversity and structure in a widespread amphibian. More specifically, we examined the association between bacterial diversity and composition and the major histocompatibility complex class II exon 2 diversity in 12 moor frog (Rana arvalis) populations belonging to two geographical clusters that show signatures of past and ongoing differential selection. We found that while bacterial alpha diversity did not differ between the two clusters, MHC alleles/supertypes and genetic diversity varied considerably depending on geography and evolutionary history. Bacterial alpha diversity was positively correlated with expected MHC heterozygosity and negatively with MHC nucleotide diversity. Furthermore, bacterial community composition showed significant variation between the two geographical clusters and between specific MHC alleles/supertypes. Our findings emphasize the importance of historical demographic events on hologenomic variation and provide new insights into how immunogenetic host variability and microbial diversity may jointly influence host fitness with consequences for disease susceptibility and population persistence.
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Affiliation(s)
- M Cortazar-Chinarro
- Animal Ecology/Department of Ecology and Genetics, Uppsala University, Uppsala, Sweden
- MEMEG/Department of Biology, Lund University, Lund, Sweden
- Department of Earth Ocean and Atmospheric Sciences, Faculty of Science 2020-2207, University of British Columbia, Vancouver, British Columbia, Canada
| | - A Richter-Boix
- Department of Political and Social Science, Pompeu Fabra University, Barcelona, Spain
| | - P Rödin-Mörch
- Animal Ecology/Department of Ecology and Genetics, Uppsala University, Uppsala, Sweden
| | - P Halvarsson
- Parasitology/Department of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - J B Logue
- Aquatic Ecology/Department of Biology, Lund University, Lund, Sweden
- SLU University Library, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - A Laurila
- Animal Ecology/Department of Ecology and Genetics, Uppsala University, Uppsala, Sweden
| | - J Höglund
- Animal Ecology/Department of Ecology and Genetics, Uppsala University, Uppsala, Sweden
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Minias P, Peng WXVH, Matson KD. Evolutionary trade-off between innate and acquired immune defences in birds. Front Zool 2023; 20:32. [PMID: 37684615 PMCID: PMC10486109 DOI: 10.1186/s12983-023-00511-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Accepted: 09/01/2023] [Indexed: 09/10/2023] Open
Abstract
BACKGROUND The development, maintenance, and use of immune defences are costly. Therefore, animals face trade-offs in terms of resource allocation within their immune system and between their immune system and other physiological processes. To maximize fitness, evolution may favour investment in one immunological defence or subsystem over another in a way that matches a species broader life history strategy. Here, we used phylogenetically-informed comparative analyses to test for relationships between two immunological components. Natural antibodies and complement were used as proxies for the innate branch; structural complexity of the major histocompatibility complex (MHC) region was used for the acquired branch. RESULTS We found a negative association between the levels of natural antibodies (i.e., haemagglutination titre) and the total MHC gene copy number across the avian phylogeny, both at the species and family level. The family-level analysis indicated that this association was apparent for both MHC-I and MHC-II, when copy numbers within these two MHC regions were analysed separately. The association remained significant after controlling for basic life history components and for ecological traits commonly linked to pathogen exposure. CONCLUSION Our results provide the first phylogenetically robust evidence for an evolutionary trade-off within the avian immune system, with a more developed acquired immune system (i.e., more complex MHC architecture) in more derived bird lineages (e.g., passerines) being accompanied by an apparent downregulation of the innate 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.
| | - Wei-Xuan V-H Peng
- Wildlife Ecology and Conservation Group, Wageningen University & Research, Droevendaalsesteeg 3a, 6708PB, Wageningen, Netherlands
| | - Kevin D Matson
- Wildlife Ecology and Conservation Group, Wageningen University & Research, Droevendaalsesteeg 3a, 6708PB, Wageningen, Netherlands
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Włodarczyk R, Těšický M, Vinkler M, Novotný M, Remisiewicz M, Janiszewski T, Minias P. Divergent evolution drives high diversity of toll-like receptors (TLRs) in passerine birds: Buntings and finches. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2023; 144:104704. [PMID: 37019350 DOI: 10.1016/j.dci.2023.104704] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Revised: 03/29/2023] [Accepted: 03/29/2023] [Indexed: 06/05/2023]
Abstract
Toll-like receptors (TLRs) form a key component of animal innate immunity, being responsible for recognition of conserved microbial structures. As such, TLRs may be subject to diversifying and balancing selection, which maintains allelic variation both within and between populations. However, most research on TLRs in non-model avian species is focused on bottlenecked populations with depleted genetic variation. Here, we assessed variation at the extracellular domains of three TLR genes (TLR1LA, TLR3, TLR4) across eleven species from two passerine families of buntings (Emberizidae) and finches (Fringillidae), all having large breeding population sizes (millions of individuals). We found extraordinary TLR polymorphism in our study taxa, with >100 alleles detected at TLR1LA and TLR4 across species and high haplotype diversity (>0.75) in several species. Despite recent species divergence, no nucleotide allelic variants were shared between species, suggesting rapid TLR evolution. Higher variation at TLR1LA and TLR4 than TLR3 was associated with a stronger signal of diversifying selection, as measured with nucleotide substitutions rates and the number of positively selected sites (PSS). Structural protein modelling of TLRs showed that some PSS detected within TLR1LA and TLR4 were previously recognized as functionally important sites or were located in their proximity, possibly affecting ligand recognition. Furthermore, we identified PSS responsible for major surface electrostatic charge clustering, which may indicate their adaptive importance. Our study provides compelling evidence for the divergent evolution of TLR genes in buntings and finches and indicates that high TLR variation may be adaptively maintained via diversifying selection acting on functional ligand binding sites.
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Affiliation(s)
- Radosław Włodarczyk
- Department of Biodiversity Studies and Bioeducation, Faculty of Biology and Environmental Protection, University of Łódź, Banacha 1/3, 90-237, Łódź, Poland.
| | - Martin Těšický
- Charles University, Faculty of Science, Department of Zoology, Viničná 7, 128 43, Prague, Czech Republic
| | - Michal Vinkler
- Charles University, Faculty of Science, Department of Zoology, Viničná 7, 128 43, Prague, Czech Republic
| | - Marian Novotný
- Charles University, Faculty of Science, Department of Cell Biology, Viničná 7, 128 43, Prague, Czech Republic
| | - Magdalena Remisiewicz
- Bird Migration Research Station, Faculty of Biology, University of Gdańsk, Wita Stwosza 59, 80-308, Gdańsk, Poland
| | - Tomasz Janiszewski
- Department of Biodiversity Studies and Bioeducation, Faculty of Biology and Environmental Protection, University of Łódź, Banacha 1/3, 90-237, Łódź, Poland
| | - Piotr Minias
- 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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Winternitz J, Chakarov N, Rinaud T, Ottensmann M, Krüger O. High functional allelic diversity and copy number in both MHC classes in the common buzzard. BMC Ecol Evol 2023; 23:24. [PMID: 37355591 PMCID: PMC10290333 DOI: 10.1186/s12862-023-02135-9] [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: 11/11/2021] [Accepted: 06/12/2023] [Indexed: 06/26/2023] Open
Abstract
BACKGROUND The major histocompatibility complex (MHC), which encodes molecules that recognize various pathogens and parasites and initiates the adaptive immune response in vertebrates, is renowned for its exceptional polymorphism and is a model of adaptive gene evolution. In birds, the number of MHC genes and sequence diversity varies greatly among taxa, believed due to evolutionary history and differential selection pressures. Earlier characterization studies and recent comparative studies suggest that non-passerine species have relatively few MHC gene copies compared to passerines. Additionally, comparative studies that have looked at partial MHC sequences have speculated that non-passerines have opposite patterns of selection on MHC class I (MHC-I) and class II (MHC-II) loci than passerines: namely, greater sequence diversity and signals of selection on MHC-II than MHC-I. However, new sequencing technology is revealing much greater MHC variation than previously expected while also facilitating full sequence variant detection directly from genomic data. Our study aims to take advantage of high-throughput sequencing methods to fully characterize both classes and domains of MHC of a non-passerine bird of prey, the common buzzard (Buteo buteo), to test predictions of MHC variation and differential selection on MHC classes. RESULTS Using genetic, genomic, and transcriptomic high-throughput sequencing data, we established common buzzards have at least three loci that produce functional alleles at both MHC classes. In total, we characterize 91 alleles from 113 common buzzard chicks for MHC-I exon 3 and 41 alleles from 125 chicks for MHC-IIB exon 2. Among these alleles, we found greater sequence polymorphism and stronger diversifying selection at MHC-IIB exon 2 than MHC-I exon 3, suggesting differential selection pressures on MHC classes. However, upon further investigation of the entire peptide-binding groove by including genomic data from MHC-I exon 2 and MHC-IIA exon 2, this turned out to be false. MHC-I exon 2 was as polymorphic as MHC-IIB exon 2 and MHC-IIA exon 2 was essentially invariant. Thus, comparisons between MHC-I and MHC-II that included both domains of the peptide-binding groove showed no differences in polymorphism nor diversifying selection between the classes. Nevertheless, selection analysis indicates balancing selection has been acting on common buzzard MHC and phylogenetic inference revealed that trans-species polymorphism is present between common buzzards and species separated for over 33 million years for class I and class II. CONCLUSIONS We characterize and confirm the functionality of unexpectedly high copy number and allelic diversity in both MHC classes of a bird of prey. While balancing selection is acting on both classes, there is no evidence of differential selection pressure on MHC classes in common buzzards and this result may hold more generally once more data for understudied MHC exons becomes available.
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Affiliation(s)
- Jamie Winternitz
- Department of Animal Behaviour, Bielefeld University, Morgenbreede 45, 33615 Bielefeld, Germany
| | - Nayden Chakarov
- Department of Animal Behaviour, Bielefeld University, Morgenbreede 45, 33615 Bielefeld, Germany
| | - Tony Rinaud
- Department of Animal Behaviour, Bielefeld University, Morgenbreede 45, 33615 Bielefeld, Germany
| | - Meinolf Ottensmann
- Department of Animal Behaviour, Bielefeld University, Morgenbreede 45, 33615 Bielefeld, Germany
| | - Oliver Krüger
- Department of Animal Behaviour, Bielefeld University, Morgenbreede 45, 33615 Bielefeld, Germany
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Jia Y, Fu Q, Li B, Xu Y, Tariq A. Polymorphism analysis of major histocompatibility complex (MHC) DQB gene in the Asiatic black bear (Ursus thibetanus). MAMMAL RES 2023. [DOI: 10.1007/s13364-023-00685-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/31/2023]
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10
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Minias P, Palomar G, Dudek K, Babik W. Salamanders reveal novel trajectories of amphibian MHC evolution. Evolution 2022; 76:2436-2449. [PMID: 36000494 DOI: 10.1111/evo.14601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Revised: 07/06/2022] [Accepted: 07/29/2022] [Indexed: 01/22/2023]
Abstract
Genes of the major histocompatibility complex (MHC) code for immune proteins that are crucial for pathogen recognition in vertebrates. MHC research in nonmodel taxa has long been hampered by its genomic complexity that makes the locus-specific genotyping challenging. The recent progress in sequencing and genotyping methodologies allows an extensive phylogenetic coverage in studies of MHC evolution. Here, we analyzed the peptide-binding region of MHC class I (MHC-I) in 30 species of salamanders from six families representative of Urodela phylogeny. This extensive dataset revealed an extreme diversity of MHC-I in salamanders, both in terms of sequence diversity (about 3000 variants) and architecture (2-22 gene copies per species). The signal of positive selection was moderate and consistent between both peptide-binding domains, but varied greatly between genera. Positions of positively selected sites mostly coincided with human peptide-binding sites, suggesting similar structural properties of MHC-I molecules across distant vertebrate lineages. Finally, we provided evidence for the common intraexonic recombination at MHC-I and for the role of life history traits in the processes of MHC-I expansion/contraction. Our study revealed novel evolutionary trajectories of amphibian MHC and it contributes to the understanding of the mechanisms that generated extraordinary MHC diversity throughout vertebrate evolution.
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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
| | - Gemma Palomar
- Institute of Environmental Sciences, Faculty of Biology, Jagiellonian University, Kraków, 30-387, Poland.,Parasitology Unit, Department of Biomedicine and Biotechnology, Faculty of Pharmacy, Universidad de Alcalá (UAH), Alcalá de Henares, Madrid, 28805, Spain
| | - Katarzyna Dudek
- Institute of Environmental Sciences, Faculty of Biology, Jagiellonian University, Kraków, 30-387, Poland
| | - Wiesław Babik
- Institute of Environmental Sciences, Faculty of Biology, Jagiellonian University, Kraków, 30-387, Poland
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11
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Soper DM, Ekroth AKE, Martins MJF. Direct evidence for increased disease resistance in polyandrous broods exists only in eusocial Hymenoptera. BMC Ecol Evol 2021; 21:189. [PMID: 34670487 PMCID: PMC8527725 DOI: 10.1186/s12862-021-01925-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Accepted: 09/24/2021] [Indexed: 11/25/2022] Open
Abstract
Background The ‘genetic diversity’ hypothesis posits that polyandry evolved as a mechanism to increase genetic diversity within broods. One extension of this hypothesis is the ‘genetic diversity for disease resistance’ hypothesis (GDDRH). Originally designed for eusocial Hymenoptera, GDDRH states that polyandry will evolve as an effect of lower parasite prevalence in genetically variable broods. However, this hypothesis has been broadly applied to several other taxa. It is unclear how much empirical evidence supports GDDRH specifically, especially outside eusocial Hymenoptera. Results This question was addressed by conducting a literature review and posteriorly conducting meta-analyses on the data available using Hedges’s g. The literature review found 10 direct and 32 indirect studies with both having a strong publication bias towards Hymenoptera. Two meta-analyses were conducted and both found increased polyandry (direct tests; n = 8, g = 0.2283, p = < 0.0001) and genetic diversity generated by other mechanisms (indirect tests; n = 10, g = 0.21, p = < 0.0001) reduced parasite load. A subsequent moderator analysis revealed that there were no differences among Orders, indicating there may be applicability outside of Hymenoptera. However, due to publication bias and low sample size we must exercise caution with these results. Conclusion Despite the fact that the GDDRH was developed for Hymenoptera, it is frequently applied to other taxa. This study highlights the low amount of direct evidence supporting GDDRH, particularly outside of eusocial Hymenoptera. It calls for future research to address species that have high dispersal rates and contain mixes of solitary and communal nesting. Supplementary Information The online version contains supplementary material available at 10.1186/s12862-021-01925-3.
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Affiliation(s)
- D M Soper
- Department of Biology, University of Dallas, 1845 E. Northgate Dr., Irving, TX, 75062, USA.
| | - A K E Ekroth
- Department of Zoology, University of Oxford, 11a Mansfield Road, Oxford, OX1 3SZ, UK
| | - M J F Martins
- Interdisciplinary Center for Archaeology and Evolution of Human Behaviour (ICArEHB), Faculdade de Ciências Humanas e Sociais, Universidade do Algarve, Campus de Gambelas, 8005-139, Faro, Portugal.,Department of Paleobiology, National Museum of Natural History, Smithsonian Institution, Washington, DC, 20013-7012, USA
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12
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Vincze O, Loiseau C, Giraudeau M. Avian blood parasite richness decreases with major histocompatibility complex class I loci number. Biol Lett 2021; 17:20210253. [PMID: 34343440 DOI: 10.1098/rsbl.2021.0253] [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] [Indexed: 12/16/2022] Open
Abstract
Major histocompatibility complex (MHC) genes are among the most polymorphic in the vertebrate genome. The high allele diversity is believed to be maintained primarily by sexual and pathogen-mediated balancing selection. The number of MHC loci also varies greatly across vertebrates, most notably across birds. MHC proteins play key roles in presenting antigens on the cell surface for recognition by T cells, with class I proteins specifically targeting intracellular pathogens. Here, we explore the hypothesis that MHC class I diversity (measured as loci number) coevolves with haemosporidian parasite burden of the host. Using data on 54 bird species, we demonstrate that high-MHC class I diversity is associated with significantly lower richness of Plasmodium, Haemoproteus as well as overall haemosporidian parasite lineages, the former thus indicating more efficient protection against intracellular pathogens. Nonetheless, the latter associations were only detected when MHC diversity was assessed using cloning and not 454 pyrosequencing-based studies, nor across all genotyping methods combined. Our results indicate that high-MHC class I diversity might play a key role in providing qualitative resistance against diverse haemosporidian parasites in birds, but further clarification is needed for the origin of contrasting results when using different genotyping methods for MHC loci quantification.
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Affiliation(s)
- Orsolya Vincze
- CREEC, MIVEGEC, UMR IRD 224-CNRS 5290-Université de Montpellier, Montpellier, France.,CREES Centre for Research on the Ecology and Evolution of Disease, Montpellier, France.,Littoral, Environnement et Sociétés (LIENSs), UMR 7266 CNRS-La Rochelle Université, 2 Rue Olympe de Gouges, FR-17000 La Rochelle, France.,Institute of Aquatic Ecology, Centre for Ecological Research, 4026 Debrecen, Hungary.,Evolutionary Ecology Group, Hungarian Department of Biology and Ecology, Babeş-Bolyai University, Clinicilor Street 5-7, RO-400006 Cluj-Napoca, Romania
| | - Claire Loiseau
- CIBIO-InBIO - Research Center in Biodiversity and Genetic Resources, InBIO Associate Laboratory, Campus de Vairão, 7 Rua Padre Armando Quintas, 4485-661 Vairão, Portugal.,CEFE, Université de Montpellier, CNRS, Montpellier, France
| | - Mathieu Giraudeau
- CREEC, MIVEGEC, UMR IRD 224-CNRS 5290-Université de Montpellier, Montpellier, France.,CREES Centre for Research on the Ecology and Evolution of Disease, Montpellier, France
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13
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Cornelius Ruhs E, Becker DJ, Oakey SJ, Ogunsina O, Fenton MB, Simmons NB, Martin LB, Downs CJ. Body size affects immune cell proportions in birds and non-volant mammals, but not bats. J Exp Biol 2021; 224:269058. [PMID: 34104965 DOI: 10.1242/jeb.241109] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Accepted: 06/02/2021] [Indexed: 01/02/2023]
Abstract
Powered flight has evolved several times in vertebrates and constrains morphology and physiology in ways that likely have shaped how organisms cope with infections. Some of these constraints probably have impacts on aspects of immunology, such that larger fliers might prioritize risk reduction and safety. Addressing how the evolution of flight may have driven relationships between body size and immunity could be particularly informative for understanding the propensity of some taxa to harbor many virulent and sometimes zoonotic pathogens without showing clinical disease. Here, we used a comparative framework to quantify scaling relationships between body mass and the proportions of two types of white blood cells - lymphocytes and granulocytes (neutrophils/heterophils) - across 63 bat species, 400 bird species and 251 non-volant mammal species. By using phylogenetically informed statistical models on field-collected data from wild Neotropical bats and from captive bats, non-volant mammals and birds, we show that lymphocyte and neutrophil proportions do not vary systematically with body mass among bats. In contrast, larger birds and non-volant mammals have disproportionately higher granulocyte proportions than expected for their body size. Our inability to distinguish bat lymphocyte scaling from birds and bat granulocyte scaling from all other taxa suggests there may be other ecological explanations (i.e. not flight related) for the cell proportion scaling patterns. Future comparative studies of wild bats, birds and non-volant mammals of similar body mass should aim to further differentiate evolutionary effects and other aspects of life history on immune defense and its role in the tolerance of (zoonotic) infections.
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Affiliation(s)
- Emily Cornelius Ruhs
- Global Health and Infectious Disease Research, University of South Florida, Tampa, FL 33612, USA
| | - Daniel J Becker
- Department of Biology, University of Oklahoma, Norman, OK 73019, USA
| | - Samantha J Oakey
- Global Health and Infectious Disease Research, University of South Florida, Tampa, FL 33612, USA
| | - Ololade Ogunsina
- Global Health and Infectious Disease Research, University of South Florida, Tampa, FL 33612, USA
| | - M Brock Fenton
- Department of Biology, Western University, London, ON, Canada, N6A 5B7
| | - Nancy B Simmons
- Department of Mammalogy, Division of Vertebrate Zoology, American Museum of Natural History, New York, NY 10024-5102, USA
| | - Lynn B Martin
- Global Health and Infectious Disease Research, University of South Florida, Tampa, FL 33612, USA
| | - Cynthia J Downs
- Department of Environmental and Forest Biology, SUNY College of Environmental Science and Forestry, Syracuse, NY 13210, USA
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14
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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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15
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Relaxation of selective constraints shapes variation of toll-like receptors in a colonial waterbird, the black-headed gull. Immunogenetics 2020; 72:251-262. [PMID: 31996941 PMCID: PMC7182547 DOI: 10.1007/s00251-020-01156-8] [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: 11/11/2019] [Accepted: 01/14/2020] [Indexed: 11/01/2022]
Abstract
Nonspecific innate immune response is activated by toll-like receptors (TLRs), which recognize conserved molecular motifs characteristic for a broad spectrum of pathogens. In this study, we examined nucleotide substitution patterns and allelic diversity at five TLR genes in a wild nonpasserine bird, the black-headed gull Chroicocephalus ridibundus. We hypothesized that balancing selection can maintain high allelic diversity of TLR genes in the black-headed gull because of its ecological characteristics, coloniality, and migratoriness, which are associated with increased exposure and transmission of pathogens. Although we found moderately high levels of sequence polymorphism (8-49 haplotypes retrieved per locus within a sample of 60 individuals), most of these haplotypes were recorded at low frequencies within our study population. At the same time, we found no convincing evidence for the role of balancing selection in the maintenance of this variation (Tajima's D < 0.5), and sites with a significant excess of nonsynonymous mutations (dN/dS > 1) were recorded only at two loci (TLR5 and TLR7). This pattern is consistent with relaxation of selective constraints, where most mutations are slightly deleterious and usually removed by purifying selection. No differences in the diversity and nucleotide substitution rates were found between endosomal loci responsible for viral RNA sensing and loci responsible for the recognition of extracellular pathogens. Our study provides the first information on evolutionary mechanisms shaping polymorphism of TLRs in a species from Lari suborder (gulls and allies) and suggests that TLR genes may be poorly responsive to ecological and life-history characteristics of hosts.
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16
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O'Connor EA, Westerdahl H, Burri R, Edwards SV. Avian MHC Evolution in the Era of Genomics: Phase 1.0. Cells 2019; 8:E1152. [PMID: 31561531 PMCID: PMC6829271 DOI: 10.3390/cells8101152] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Revised: 09/16/2019] [Accepted: 09/20/2019] [Indexed: 12/14/2022] Open
Abstract
Birds are a wonderfully diverse and accessible clade with an exceptional range of ecologies and behaviors, making the study of the avian major histocompatibility complex (MHC) of great interest. In the last 20 years, particularly with the advent of high-throughput sequencing, the avian MHC has been explored in great depth in several dimensions: its ability to explain ecological patterns in nature, such as mating preferences; its correlation with parasite resistance; and its structural evolution across the avian tree of life. Here, we review the latest pulse of avian MHC studies spurred by high-throughput sequencing. Despite high-throughput approaches to MHC studies, substantial areas remain in need of improvement with regard to our understanding of MHC structure, diversity, and evolution. Recent studies of the avian MHC have nonetheless revealed intriguing connections between MHC structure and life history traits, and highlight the advantages of long-term ecological studies for understanding the patterns of MHC variation in the wild. Given the exceptional diversity of birds, their accessibility, and the ease of sequencing their genomes, studies of avian MHC promise to improve our understanding of the many dimensions and consequences of MHC variation in nature. However, significant improvements in assembling complete MHC regions with long-read sequencing will be required for truly transformative studies.
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Affiliation(s)
| | | | - Reto Burri
- Department of Population Ecology, Institute of Ecology & Evolution, Friedrich Schiller University Jena, 07737 Jena, Germany.
| | - Scott V Edwards
- Department of Organismic and Evolutionary Biology and Museum of Comparative Zoology, Harvard University, Cambridge, MA 02138, USA.
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17
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Multiplicative fitness, rapid haplotype discovery, and fitness decay explain evolution of human MHC. Proc Natl Acad Sci U S A 2019; 116:14098-14104. [PMID: 31227609 DOI: 10.1073/pnas.1714436116] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The major histocompatibility complex (MHC) is a central component of the vertebrate immune system and hence evolves in the regime of a host-pathogen evolutionary race. The MHC is associated with quantitative traits which directly affect fitness and are subject to selection pressure. The evolution of haplotypes at the MHC HLA (HLA) locus is generally thought to be governed by selection for increased diversity that is manifested in overdominance and/or negative frequency-dependent selection (FDS). However, recently, a model combining purifying selection on haplotypes and balancing selection on alleles has been proposed. We compare the predictions of several population dynamics models of haplotype frequency evolution to the distributions derived from 6.59-million-donor HLA typings from the National Marrow Donor Program registry. We show that models that combine a multiplicative fitness function, extremely high haplotype discovery rates, and exponential fitness decay over time produce the best fit to the data for most of the analyzed populations. In contrast, overdominance is not supported, and population substructure does not explain the observed haplotype frequencies. Furthermore, there is no evidence of negative FDS. Thus, multiplicative fitness, rapid haplotype discovery, and rapid fitness decay appear to be the major factors shaping the HLA haplotype frequency distribution in the human population.
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18
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Minias P. Evolution of heterophil/lymphocyte ratios in response to ecological and life‐history traits: A comparative analysis across the avian tree of life. J Anim Ecol 2019; 88:554-565. [DOI: 10.1111/1365-2656.12941] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Accepted: 11/13/2018] [Indexed: 01/25/2023]
Affiliation(s)
- Piotr Minias
- Department of Biodiversity Studies and BioeducationFaculty of Biology and Environmental ProtectionUniversity of Łódź Łódź Poland
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19
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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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20
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Minias P, Pikus E, Whittingham LA, Dunn PO. Evolution of Copy Number at the MHC Varies across the Avian Tree of Life. Genome Biol Evol 2019; 11:17-28. [PMID: 30476037 PMCID: PMC6319602 DOI: 10.1093/gbe/evy253] [Citation(s) in RCA: 55] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/20/2018] [Indexed: 12/24/2022] Open
Abstract
The evolution of the major histocompatibility complex (MHC) is shaped by frequent gene duplications and deletions, which generate extensive variation in the number of loci (gene copies) between different taxa. Here, we collected estimates of copy number at the MHC for over 250 bird species from 68 families. We found contrasting patterns of copy number evolution between MHC class I and class IIB, which encode receptors for intra- and extracellular pathogens, respectively. Across the avian evolutionary tree, there was evidence of accelerated evolution and stabilizing selection acting on copy number at class I, while copy number at class IIB was primarily influenced by fluctuating selection and drift. Reconstruction of MHC copy number variation showed ancestrally low numbers of MHC loci in nonpasserines and evolution toward larger numbers of loci in passerines. Different passerine lineages had the highest duplication rates for MHC class I (Sylvioidea) and class IIB (Muscicapoidea and Passeroidea). We also found support for the correlated evolution of MHC copy number and life-history traits such as lifespan and migratory behavior. These results suggest that MHC copy number evolution in birds has been driven by life histories and differences in exposure to intra- and extracellular pathogens.
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Affiliation(s)
- Piotr Minias
- Department of Biodiversity Studies and Bioeducation, Faculty of Biology and Environmental Protection, University of Lódz, Poland
| | - Ewa Pikus
- Department of Biodiversity Studies and Bioeducation, Faculty of Biology and Environmental Protection, University of Lódz, Poland
| | - Linda A Whittingham
- Behavioral and Molecular Ecology Group, Department of Biological Sciences, University of Wisconsin-Milwaukee
| | - Peter O Dunn
- Department of Biodiversity Studies and Bioeducation, Faculty of Biology and Environmental Protection, University of Łódź, Poland.,Behavioral and Molecular Ecology Group, Department of Biological Sciences, University of Wisconsin-Milwaukee
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21
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Dornburg A, Su Z, Townsend JP. Optimal Rates for Phylogenetic Inference and Experimental Design in the Era of Genome-Scale Data Sets. Syst Biol 2018; 68:145-156. [PMID: 29939341 DOI: 10.1093/sysbio/syy047] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2018] [Accepted: 06/13/2018] [Indexed: 02/02/2023] Open
Abstract
With the rise of genome-scale data sets, there has been a call for increased data scrutiny and careful selection of loci that are appropriate to use in an attempt to resolve a phylogenetic problem. Such loci should maximize phylogenetic information content while minimizing the risk of homoplasy. Theory posits the existence of characters that evolve at an optimum rate, and efforts to determine optimal rates of inference have been a cornerstone of phylogenetic experimental design for over two decades. However, both theoretical and empirical investigations of optimal rates have varied dramatically in their conclusions: spanning no relationship to a tight relationship between the rate of change and phylogenetic utility. Herein, we synthesize these apparently contradictory views, demonstrating both empirical and theoretical conditions under which each is correct. We find that optimal rates of characters-not genes-are generally robust to most experimental design decisions. Moreover, consideration of site rate heterogeneity within a given locus is critical to accurate predictions of utility. Factors such as taxon sampling or the targeted number of characters providing support for a topology are additionally critical to the predictions of phylogenetic utility based on the rate of character change. Further, optimality of rates and predictions of phylogenetic utility are not equivalent, demonstrating the need for further development of comprehensive theory of phylogenetic experimental design. [Divergence time; GC bias; homoplasy; incongruence; information content; internode length; optimal rates; phylogenetic informativeness; phylogenetic theory; phylogenetic utility; phylogenomics; signal and noise; subtending branch length; state space; taxon and character sampling.].
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Affiliation(s)
- Alex Dornburg
- North Carolina Museum of Natural Sciences, Raleigh, 1671 Goldstar Drive, NC 27601, USA
| | - Zhuo Su
- Department of Ecology and Evolutionary Biology, Yale University, New Haven, 165 Prospect Street, CT 06525, USA
| | - Jeffrey P Townsend
- Department of Ecology and Evolutionary Biology, Yale University, New Haven, 165 Prospect Street, CT 06525, USA
- Department of Biostatistics, Yale University, New Haven, 60 College Street, CT 06510, USA
- Program in Computational Biology and Bioinformatics, Yale University, New Haven, 300 George Street, CT 06511, USA
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22
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Whittingham LA, Dunn PO, Freeman-Gallant CR, Taff CC, Johnson JA. Major histocompatibility complex variation and blood parasites in resident and migratory populations of the common yellowthroat. J Evol Biol 2018; 31:1544-1557. [DOI: 10.1111/jeb.13349] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2018] [Revised: 06/12/2018] [Accepted: 06/25/2018] [Indexed: 01/13/2023]
Affiliation(s)
- Linda A. Whittingham
- Behavioral and Molecular Ecology Group; Department of Biological Sciences; University of Wisconsin-Milwaukee; Milwaukee WI USA
| | - Peter O. Dunn
- Behavioral and Molecular Ecology Group; Department of Biological Sciences; University of Wisconsin-Milwaukee; Milwaukee WI USA
| | | | - Conor C. Taff
- Cornell Laboratory of Ornithology; Cornell University; Ithaca NY USA
| | - Jeff A. Johnson
- Department of Biological Sciences; Institute of Applied Sciences; University of North Texas; Denton TX USA
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23
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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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24
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O’Connor EA, Cornwallis CK, Hasselquist D, Nilsson JÅ, Westerdahl H. The evolution of immunity in relation to colonization and migration. Nat Ecol Evol 2018; 2:841-849. [DOI: 10.1038/s41559-018-0509-3] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2017] [Accepted: 02/19/2018] [Indexed: 12/12/2022]
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25
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Raven N, Lisovski S, Klaassen M, Lo N, Madsen T, Ho SYW, Ujvari B. Purifying selection and concerted evolution of RNA-sensing toll-like receptors in migratory waders. INFECTION GENETICS AND EVOLUTION 2017; 53:135-145. [PMID: 28528860 DOI: 10.1016/j.meegid.2017.05.012] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2016] [Revised: 05/15/2017] [Accepted: 05/17/2017] [Indexed: 01/05/2023]
Abstract
Migratory birds encounter a broad range of pathogens during their journeys, making them ideal models for studying immune gene evolution. Despite the potential value of these species to immunoecology and disease epidemiology, previous studies have typically focused on their adaptive immune gene repertoires. In this study, we examined the evolution of innate immune genes in three long-distance migratory waders (order Charadriiformes). We analysed two parts of the extracellular domains of two Toll-like receptors (TLR3 and TLR7) involved in virus recognition in the Sanderling (Calidris alba), Red-necked Stint (Calidris ruficollis), and Ruddy Turnstone (Arenaria interpres). Our analysis was extended to 50 avian species for which whole-genome sequences were available, including two additional waders. We found that the inferred relationships among avian TLR3 and TLR7 do not match the whole-genome phylogeny of birds. Further analyses showed that although both loci are predominantly under purifying selection, the evolution of the extracellular domain of avian TLR3 has also been driven by episodic diversifying selection. TLR7 was found to be duplicated in all five wader species and in two other orders of birds, Cuculiformes and Passeriformes. The duplication is likely to have occurred in the ancestor of each order, and the duplicated copies appear to be undergoing concerted evolution. The phylogenetic relationships of wader TLR7 matched those of the five wader species, but that of TLR3 did not. Instead, the tree inferred from TLR3 showed potential associations with the species' ecology, including migratory behaviour and exposure to pathogens. Our study demonstrates the importance of combining immunological and ecological knowledge to understand the impact of immune gene polymorphism on the evolutionary ecology of infectious diseases.
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Affiliation(s)
- Nynke Raven
- Centre for Integrative Ecology, School of Life and Environmental Sciences, Deakin University, Waurn Ponds, VIC 3216, Australia
| | - Simeon Lisovski
- Centre for Integrative Ecology, School of Life and Environmental Sciences, Deakin University, Waurn Ponds, VIC 3216, Australia
| | - Marcel Klaassen
- Centre for Integrative Ecology, School of Life and Environmental Sciences, Deakin University, Waurn Ponds, VIC 3216, Australia
| | - Nathan Lo
- School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW 2006, Australia
| | - Thomas Madsen
- Centre for Integrative Ecology, School of Life and Environmental Sciences, Deakin University, Waurn Ponds, VIC 3216, Australia
| | - Simon Y W Ho
- School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW 2006, Australia
| | - Beata Ujvari
- Centre for Integrative Ecology, School of Life and Environmental Sciences, Deakin University, Waurn Ponds, VIC 3216, Australia.
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26
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Wang Z, Zhou X, Lin Q, Fang W, Chen X. Diversity and selection of MHC class I genes in the vulnerable Chinese egret (Egretta eulophotes). PLoS One 2017; 12:e0176671. [PMID: 28467494 PMCID: PMC5415105 DOI: 10.1371/journal.pone.0176671] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2016] [Accepted: 04/16/2017] [Indexed: 11/19/2022] Open
Abstract
The genes of major histocompatibility complex (MHC) are important to vertebrate immune system. In this study, two new MHC class I genes, designated as Egeu-UAA and Egeu-UBA, were discovered in the vulnerable Chinese egret (Egretta eulophotes). Using a full length DNA and cDNA produced by PCR and RACE methods, these two MHC class I loci were characterized in the genome of the Chinese egret and were also found to be expressed in liver and blood. Both new genes showed the expected eight exons and were similar to two copies of the minimal essential MHC complex of chicken. In genetic diversity, 14 alleles (8 for UAA and 6 for UBA) in the MHC class I gene exon 3 were found in 60 individuals using locus-specific primers and showed little polymorphism. Only three potential amino acid residues were detected under positive selection in potential peptide-binding regions (PBRs) by Bayesian analysis. These new results provide the fundamental basis for further studies to elucidate the molecular mechanisms and significance of MHC molecular adaptation in vulnerable Chinese egret and other ardeids, finding that have not been previously reported.
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Affiliation(s)
- Zeng Wang
- Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, College of the Environment and Ecology, Xiamen University, Xiamen, Fujian, People's Republic of China
| | - Xiaoping Zhou
- Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, College of the Environment and Ecology, Xiamen University, Xiamen, Fujian, People's Republic of China
| | - Qingxian Lin
- Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, College of the Environment and Ecology, Xiamen University, Xiamen, Fujian, People's Republic of China
| | - Wenzhen Fang
- Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, College of the Environment and Ecology, Xiamen University, Xiamen, Fujian, People's Republic of China
- * E-mail: (WF); (XC)
| | - Xiaolin Chen
- Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, College of the Environment and Ecology, Xiamen University, Xiamen, Fujian, People's Republic of China
- * E-mail: (WF); (XC)
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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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