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Mao Y, Peng T, Shao F, Zhao Q, Peng Z. Molecular evolution of the hemoglobin gene family across vertebrates. Genetica 2023:10.1007/s10709-023-00187-9. [PMID: 37069365 DOI: 10.1007/s10709-023-00187-9] [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: 09/02/2022] [Accepted: 04/11/2023] [Indexed: 04/19/2023]
Abstract
Adaptation to various altitudes and oxygen levels is a major aspect of vertebrate evolution. Hemoglobin is an erythrocyte protein belonging to the globin superfamily, and the α-, β-globin genes of jawed vertebrates encode tetrameric ((α2β2) hemoglobin, which contributes to aerobic metabolism by delivering oxygen from the respiratory exchange surfaces into cells. However, there are various gaps in knowledge regarding hemoglobin gene evolution, including patterns in cartilaginous fish and the roles of gene conversion in various taxa. Hence, we evaluated the evolutionary history of the vertebrate hemoglobin gene family by analyses of 97 species representing all classes of vertebrates. By genome-wide analyses, we extracted 879 hemoglobin sequences. Members of the hemoglobin gene family were conserved in birds and reptiles but variable in mammals, amphibians, and teleosts. Gene motifs, structures, and synteny were relatively well-conserved among vertebrates. Our results revealed that purifying selection contributed substantially to the evolution of all vertebrate hemoglobin genes, with mean dN/dS (ω) values ranging from 0.057 in teleosts to 0.359 in reptiles. In general, after the fish-specific genome duplication, the teleost hemoglobin genes showed variation in rates of evolution, and the β-globin genes showed relatively high ω values after a gene transposition event in amniotes. We also observed that the frequency of gene conversion was high in amniotes, with fewer hemoglobin genes and higher rates of evolution. Collectively, our findings provide detail insight into complex evolutionary processes shaping the vertebrate hemoglobin gene family, involving gene duplication, gene loss, purifying selection, and gene conversion.
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Affiliation(s)
- Yang Mao
- Key Laboratory of Freshwater Fish Reproduction and Development (Ministry of Education), Southwest University School of Life Sciences, Chongqing, 400715, China
- Clinical Research Center, The Second Affiliated Hospital, Army Medical University, Chongqing, 400037, China
| | - Taotao Peng
- Department of Anesthesiology, Second Affiliated Hospital, Army Medical University, Chongqing, 400037, China
| | - Feng Shao
- Key Laboratory of Freshwater Fish Reproduction and Development (Ministry of Education), Southwest University School of Life Sciences, Chongqing, 400715, China
| | - Qingyuan Zhao
- Key Laboratory of Freshwater Fish Reproduction and Development (Ministry of Education), Southwest University School of Life Sciences, Chongqing, 400715, China
| | - Zuogang Peng
- Key Laboratory of Freshwater Fish Reproduction and Development (Ministry of Education), Southwest University School of Life Sciences, Chongqing, 400715, China.
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2
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Signore AV, Paijmans JLA, Hofreiter M, Fago A, Weber RE, Springer MS, Campbell KL. Emergence of a Chimeric Globin Pseudogene and Increased Hemoglobin Oxygen Affinity Underlie the Evolution of Aquatic Specializations in Sirenia. Mol Biol Evol 2019; 36:1134-1147. [PMID: 30828717 PMCID: PMC6526914 DOI: 10.1093/molbev/msz044] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2018] [Revised: 02/13/2019] [Accepted: 02/27/2019] [Indexed: 12/13/2022] Open
Abstract
As limits on O2 availability during submergence impose severe constraints on aerobic respiration, the oxygen binding globin proteins of marine mammals are expected to have evolved under strong evolutionary pressures during their land-to-sea transition. Here, we address this question for the order Sirenia by retrieving, annotating, and performing detailed selection analyses on the globin repertoire of the extinct Steller’s sea cow (Hydrodamalis gigas), dugong (Dugong dugon), and Florida manatee (Trichechus manatus latirostris) in relation to their closest living terrestrial relatives (elephants and hyraxes). These analyses indicate most loci experienced elevated nucleotide substitution rates during their transition to a fully aquatic lifestyle. While most of these genes evolved under neutrality or strong purifying selection, the rate of nonsynonymous/synonymous replacements increased in two genes (Hbz-T1 and Hba-T1) that encode the α-type chains of hemoglobin (Hb) during each stage of life. Notably, the relaxed evolution of Hba-T1 is temporally coupled with the emergence of a chimeric pseudogene (Hba-T2/Hbq-ps) that contributed to the tandemly linked Hba-T1 of stem sirenians via interparalog gene conversion. Functional tests on recombinant Hb proteins from extant and ancestral sirenians further revealed that the molecular remodeling of Hba-T1 coincided with increased Hb–O2 affinity in early sirenians. Available evidence suggests that this trait evolved to maximize O2 extraction from finite lung stores and suppress tissue O2 offloading, thereby facilitating the low metabolic intensities of extant sirenians. In contrast, the derived reduction in Hb–O2 affinity in (sub)Arctic Steller’s sea cows is consistent with fueling increased thermogenesis by these once colossal marine herbivores.
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Affiliation(s)
- Anthony V Signore
- Department of Biological Sciences, University of Manitoba, Winnipeg, Canada.,School of Biological Sciences, University of Nebraska, Lincoln, NE
| | | | - Michael Hofreiter
- Institute of Biochemistry and Biology, University of Potsdam, Germany
| | - Angela Fago
- Department of Bioscience, Zoophysiology, Aarhus University, Denmark
| | - Roy E Weber
- Department of Bioscience, Zoophysiology, Aarhus University, Denmark
| | - Mark S Springer
- Department of Evolution, Ecology, and Organismal Biology, University of California, Riverside, CA
| | - Kevin L Campbell
- Department of Biological Sciences, University of Manitoba, Winnipeg, Canada
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3
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Gene tree species tree reconciliation with gene conversion. J Math Biol 2019; 78:1981-2014. [PMID: 30767052 DOI: 10.1007/s00285-019-01331-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2017] [Revised: 10/03/2018] [Indexed: 01/19/2023]
Abstract
Gene tree/species tree reconciliation is a recent decisive progress in phylogenetic methods, accounting for the possible differences between gene histories and species histories. Reconciliation consists in explaining these differences by gene-scale events such as duplication, loss, transfer, which translates mathematically into a mapping between gene tree nodes and species tree nodes or branches. Gene conversion is a frequent and important evolutionary event, which results in the replacement of a gene by a copy of another from the same species and in the same gene tree. Including this event in reconciliation models has never been attempted because it introduces a dependency between lineages, and standard algorithms based on dynamic programming become ineffective. We propose here a novel mathematical framework including gene conversion as an evolutionary event in gene tree/species tree reconciliation. We describe a randomized algorithm that finds, in polynomial running time, a reconciliation minimizing the number of duplications, losses and conversions in the case when their weights are equal. We show that the space of optimal reconciliations includes an analog of the last common ancestor reconciliation, but is not limited to it. Our algorithm outputs any optimal reconciliation with a non-null probability. We argue that this study opens a research avenue on including gene conversion in reconciliation, and discuss its possible importance in biology.
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Daugherty MD, Schaller AM, Geballe AP, Malik HS. Evolution-guided functional analyses reveal diverse antiviral specificities encoded by IFIT1 genes in mammals. eLife 2016; 5. [PMID: 27240734 PMCID: PMC4887208 DOI: 10.7554/elife.14228] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2016] [Accepted: 04/13/2016] [Indexed: 12/21/2022] Open
Abstract
IFIT (interferon-induced with tetratricopeptide repeats) proteins are critical mediators of mammalian innate antiviral immunity. Mouse IFIT1 selectively inhibits viruses that lack 2'O-methylation of their mRNA 5' caps. Surprisingly, human IFIT1 does not share this antiviral specificity. Here, we resolve this discrepancy by demonstrating that human and mouse IFIT1 have evolved distinct functions using a combination of evolutionary, genetic and virological analyses. First, we show that human IFIT1 and mouse IFIT1 (renamed IFIT1B) are not orthologs, but are paralogs that diverged >100 mya. Second, using a yeast genetic assay, we show that IFIT1 and IFIT1B proteins differ in their ability to be suppressed by a cap 2'O-methyltransferase. Finally, we demonstrate that IFIT1 and IFIT1B have divergent antiviral specificities, including the discovery that only IFIT1 proteins inhibit a virus encoding a cap 2'O-methyltransferase. These functional data, combined with widespread turnover of mammalian IFIT genes, reveal dramatic species-specific differences in IFIT-mediated antiviral repertoires.
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Affiliation(s)
- Matthew D Daugherty
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, United States.,Howard Hughes Medical Institute, Fred Hutchinson Cancer Research Center, Seattle, United States
| | - Aaron M Schaller
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, United States
| | - Adam P Geballe
- Divisions of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, United States.,Clinical Research, Fred Hutchinson Cancer Research Center, Seattle, United States.,Department of Microbiology, University of Washington School of Medicine, Seattle, United States.,Department of Medicine, University of Washington School of Medicine, Seattle, United States
| | - Harmit S Malik
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, United States.,Howard Hughes Medical Institute, Fred Hutchinson Cancer Research Center, Seattle, United States
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López de Padilla CM, Niewold TB. The type I interferons: Basic concepts and clinical relevance in immune-mediated inflammatory diseases. Gene 2015; 576:14-21. [PMID: 26410416 DOI: 10.1016/j.gene.2015.09.058] [Citation(s) in RCA: 75] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2015] [Revised: 09/04/2015] [Accepted: 09/22/2015] [Indexed: 02/08/2023]
Abstract
There is increasing scientific and clinical interest in elucidating the biology of type I Interferons, which began approximately 60 years ago with the concept of "viral interference", a property that reduces the ability of a virus to infect cells. Although our understanding of the multiple cellular and molecular functions of interferons has advanced significantly, much remains to be learned and type I Interferons remain an active and fascinating area of inquiry. In this review, we cover some general aspects of type I interferon genes, with emphasis on interferon-alpha, and various aspects of molecular mechanisms triggered by type I interferons and toll-like receptor signaling by the Janus activated kinase/signal transducer activation of transcription (JAK-STAT) pathway and interferon regulatory factor pathway. We will also describe the role of type I interferons in autoimmune and inflammatory diseases, and its potential use as therapeutic agent.
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Affiliation(s)
| | - Timothy B Niewold
- Division of Rheumatology and Department of Immunology, Mayo Clinic, Rochester, MN 55905, USA.
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Moleirinho A, Lopes AM, Seixas S, Morales-Hojas R, Prata MJ, Amorim A. Distinctive patterns of evolution of the δ-globin gene (HBD) in primates. PLoS One 2015; 10:e0123365. [PMID: 25853817 PMCID: PMC4390247 DOI: 10.1371/journal.pone.0123365] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2014] [Accepted: 03/02/2015] [Indexed: 11/18/2022] Open
Abstract
In most vertebrates, hemoglobin (Hb) is a heterotetramer composed of two dissimilar globin chains, which change during development according to the patterns of expression of α- and β-globin family members. In placental mammals, the β-globin cluster includes three early-expressed genes, ε(HBE)-γ(HBG)-ψβ(HBBP1), and the late expressed genes, δ (HBD) and β (HBB). While HBB encodes the major adult β-globin chain, HBD is weakly expressed or totally silent. Paradoxically, in human populations HBD shows high levels of conservation typical of genes under strong evolutionary constraints, possibly due to a regulatory role in the fetal-to-adult switch unique of Anthropoid primates. In this study, we have performed a comprehensive phylogenetic and comparative analysis of the two adult β-like globin genes in a set of diverse mammalian taxa, focusing on the evolution and functional divergence of HBD in primates. Our analysis revealed that anthropoids are an exception to a general pattern of concerted evolution in placental mammals, showing a high level of sequence conservation at HBD, less frequent and shorter gene conversion events. Moreover, this lineage is unique in the retention of a functional GATA-1 motif, known to be involved in the control of the developmental expression of the β-like globin genes. We further show that not only the mode but also the rate of evolution of the δ-globin gene in higher primates are strictly associated with the fetal/adult β-cluster developmental switch. To gain further insight into the possible functional constraints that have been shaping the evolutionary history of HBD in primates, we calculated dN/dS (ω) ratios under alternative models of gene evolution. Although our results indicate that HBD might have experienced different selective pressures throughout primate evolution, as shown by different ω values between apes and Old World Monkeys + New World Monkeys (0.06 versus 0.43, respectively), these estimates corroborated a constrained evolution for HBD in Anthropoid lineages, which is unlikely to be related to protein function. Collectively, these findings suggest that sequence change at the δ-globin gene has been under strong selective constraints over 65 Myr of primate evolution, likely due to a regulatory role in ontogenic switches of gene expression.
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Affiliation(s)
- Ana Moleirinho
- Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
- IPATIMUP–Institute of Molecular Pathology and Immunology, University of Porto, Porto, Portugal
- Department of Biology, Faculty of Sciences, University of Porto, Porto, Portugal
- * E-mail:
| | - Alexandra M. Lopes
- Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
- IPATIMUP–Institute of Molecular Pathology and Immunology, University of Porto, Porto, Portugal
| | - Susana Seixas
- Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
- IPATIMUP–Institute of Molecular Pathology and Immunology, University of Porto, Porto, Portugal
| | - Ramiro Morales-Hojas
- Genetics and Genomics Group, The Pirbright Institute, Compton Laboratory, Compton, Berkshire, United Kingdom
| | - Maria J. Prata
- Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
- IPATIMUP–Institute of Molecular Pathology and Immunology, University of Porto, Porto, Portugal
- Department of Biology, Faculty of Sciences, University of Porto, Porto, Portugal
| | - António Amorim
- Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
- IPATIMUP–Institute of Molecular Pathology and Immunology, University of Porto, Porto, Portugal
- Department of Biology, Faculty of Sciences, University of Porto, Porto, Portugal
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Opazo JC, Hoffmann FG, Natarajan C, Witt CC, Berenbrink M, Storz JF. Gene turnover in the avian globin gene families and evolutionary changes in hemoglobin isoform expression. Mol Biol Evol 2015; 32:871-87. [PMID: 25502940 PMCID: PMC4379397 DOI: 10.1093/molbev/msu341] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The apparent stasis in the evolution of avian chromosomes suggests that birds may have experienced relatively low rates of gene gain and loss in multigene families. To investigate this possibility and to explore the phenotypic consequences of variation in gene copy number, we examined evolutionary changes in the families of genes that encode the α- and β-type subunits of hemoglobin (Hb), the tetrameric α2β2 protein responsible for blood-O2 transport. A comparative genomic analysis of 52 bird species revealed that the size and membership composition of the α- and β-globin gene families have remained remarkably constant during approximately 100 My of avian evolution. Most interspecific variation in gene content is attributable to multiple independent inactivations of the α(D)-globin gene, which encodes the α-chain subunit of a functionally distinct Hb isoform (HbD) that is expressed in both embryonic and definitive erythrocytes. Due to consistent differences in O2-binding properties between HbD and the major adult-expressed Hb isoform, HbA (which incorporates products of the α(A)-globin gene), recurrent losses of α(D)-globin contribute to among-species variation in blood-O2 affinity. Analysis of HbA/HbD expression levels in the red blood cells of 122 bird species revealed high variability among lineages and strong phylogenetic signal. In comparison with the homologous gene clusters in mammals, the low retention rate for lineage-specific gene duplicates in the avian globin gene clusters suggests that the developmental regulation of Hb synthesis in birds may be more highly conserved, with orthologous genes having similar stage-specific expression profiles and similar functional properties in disparate taxa.
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Affiliation(s)
- Juan C Opazo
- Instituto de Ciencias Ambientales y Evolutivas, Facultad de Ciencias, Universidad Austral de Chile, Valdivia, Chile
| | - Federico G Hoffmann
- Department of Biochemistry, Molecular Biology, Entomology, and Plant Pathology, Mississippi State University Institute for Genomics, Biocomputing, and Biotechnology, Mississippi State University
| | | | - Christopher C Witt
- Department of Biology, University of New Mexico Museum of Southwestern Biology, University of New Mexico
| | - Michael Berenbrink
- Institute of Integrative Biology, University of Liverpool, Liverpool, United Kingdom
| | - Jay F Storz
- School of Biological Sciences, University of Nebraska, Lincoln
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Sezutsu H, Le Goff G, Feyereisen R. Origins of P450 diversity. Philos Trans R Soc Lond B Biol Sci 2013; 368:20120428. [PMID: 23297351 DOI: 10.1098/rstb.2012.0428] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The P450 enzymes maintain a conserved P450 fold despite a considerable variation in sequence. The P450 family even includes proteins that lack the single conserved cysteine and are therefore no longer haem-thiolate proteins. The mechanisms of successive gene duplications leading to large families in plants and animals are well established. Comparisons of P450 CYP gene clusters in related species illustrate the rapid changes in CYPome sizes. Examples of CYP copy number variation with effects on fitness are emerging, and these provide an opportunity to study the proximal causes of duplication or pseudogenization. Birth and death models can explain the proliferation of CYP genes that is amply illustrated by the sequence of every new genome. Thus, the distribution of P450 diversity within the CYPome of plants and animals, a few families with many genes (P450 blooms) and many families with few genes, follows similar power laws in both groups. A closer look at some families with few genes shows that these, often single member families, are not stable during evolution. The enzymatic prowess of P450 may predispose them to switch back and forth between metabolism of critical structural or signal molecules and metabolism dedicated to environmental response.
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Affiliation(s)
- Hideki Sezutsu
- National Institute of Agrobiological Sciences, 1-2 Ohwashi, Tsukuba, Ibaraki 3058634, Japan
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9
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Abstract
Insights into the evolution of hemoglobins and their genes are an abundant source of ideas regarding hemoglobin function and regulation of globin gene expression. This article presents the multiple genes and gene families encoding human globins, summarizes major events in the evolution of the hemoglobin gene clusters, and discusses how these studies provide insights into regulation of globin genes. Although the genes in and around the α-like globin gene complex are relatively stable, the β-like globin gene clusters are more dynamic, showing evidence of transposition to a new locus and frequent lineage-specific expansions and deletions. The cis-regulatory modules controlling levels and timing of gene expression are a mix of conserved and lineage-specific DNA, perhaps reflecting evolutionary constraint on core regulatory functions shared broadly in mammals and adaptive fine-tuning in different orders of mammals.
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Affiliation(s)
- Ross C Hardison
- Center for Comparative Genomics and Bioinformatics, Huck Institute of Genome Sciences, Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA 16802, USA.
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10
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Genomic structure and evolution of multigene families: "flowers" on the human genome. INTERNATIONAL JOURNAL OF EVOLUTIONARY BIOLOGY 2012; 2012:917678. [PMID: 22779033 PMCID: PMC3388347 DOI: 10.1155/2012/917678] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/29/2011] [Revised: 04/06/2012] [Accepted: 04/09/2012] [Indexed: 11/17/2022]
Abstract
We report the results of an extensive investigation of genomic structures in the human genome, with a particular focus on relatively large repeats (>50 kb) in adjacent chromosomal regions. We named such structures “Flowers” because the pattern observed on dot plots resembles a flower. We detected a total of 291 Flowers in the human genome. They were predominantly located in euchromatic regions. Flowers are gene-rich compared to the average gene density of the genome. Genes involved in systems receiving environmental information, such as immunity and detoxification, were overrepresented in Flowers. Within a Flower, the mean number of duplication units was approximately four. The maximum and minimum identities between homologs in a Flower showed different distributions; the maximum identity was often concentrated to 100% identity, while the minimum identity was evenly distributed in the range of 78% to 100%. Using a gene conversion detection test, we found frequent and/or recent gene conversion events within the tested Flowers. Interestingly, many of those converted regions contained protein-coding genes. Computer simulation studies suggest that one role of such frequent gene conversions is the elongation of the life span of gene families in a Flower by the resurrection of pseudogenes.
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Song G, Riemer C, Dickins B, Kim HL, Zhang L, Zhang Y, Hsu CH, Hardison RC, Nisc Comparative Sequencing Program, Green ED, Miller W. Revealing mammalian evolutionary relationships by comparative analysis of gene clusters. Genome Biol Evol 2012; 4:586-601. [PMID: 22454131 PMCID: PMC3342878 DOI: 10.1093/gbe/evs032] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/19/2012] [Indexed: 12/13/2022] Open
Abstract
Many software tools for comparative analysis of genomic sequence data have been released in recent decades. Despite this, it remains challenging to determine evolutionary relationships in gene clusters due to their complex histories involving duplications, deletions, inversions, and conversions. One concept describing these relationships is orthology. Orthologs derive from a common ancestor by speciation, in contrast to paralogs, which derive from duplication. Discriminating orthologs from paralogs is a necessary step in most multispecies sequence analyses, but doing so accurately is impeded by the occurrence of gene conversion events. We propose a refined method of orthology assignment based on two paradigms for interpreting its definition: by genomic context or by sequence content. X-orthology (based on context) traces orthology resulting from speciation and duplication only, while N-orthology (based on content) includes the influence of conversion events. We developed a computational method for automatically mapping both types of orthology on a per-nucleotide basis in gene cluster regions studied by comparative sequencing, and we make this mapping accessible by visualizing the output. All of these steps are incorporated into our newly extended CHAP 2 package. We evaluate our method using both simulated data and real gene clusters (including the well-characterized α-globin and β-globin clusters). We also illustrate use of CHAP 2 by analyzing four more loci: CCL (chemokine ligand), IFN (interferon), CYP2abf (part of cytochrome P450 family 2), and KIR (killer cell immunoglobulin-like receptors). These new methods facilitate and extend our understanding of evolution at these and other loci by adding automated accurate evolutionary inference to the biologist's toolkit. The CHAP 2 package is freely available from http://www.bx.psu.edu/miller_lab.
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Affiliation(s)
- Giltae Song
- Center for Comparative Genomics and Bioinformatics, Pennsylvania State University, PA, USA.
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