1
|
Benham PM, Cicero C, Escalona M, Beraut E, Fairbairn C, Marimuthu MPA, Nguyen O, Sahasrabudhe R, King BL, Thomas WK, Kovach AI, Nachman MW, Bowie RCK. Remarkably High Repeat Content in the Genomes of Sparrows: The Importance of Genome Assembly Completeness for Transposable Element Discovery. Genome Biol Evol 2024; 16:evae067. [PMID: 38566597 PMCID: PMC11088854 DOI: 10.1093/gbe/evae067] [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: 11/02/2023] [Revised: 03/01/2024] [Accepted: 03/23/2024] [Indexed: 04/04/2024] Open
Abstract
Transposable elements (TE) play critical roles in shaping genome evolution. Highly repetitive TE sequences are also a major source of assembly gaps making it difficult to fully understand the impact of these elements on host genomes. The increased capacity of long-read sequencing technologies to span highly repetitive regions promises to provide new insights into patterns of TE activity across diverse taxa. Here we report the generation of highly contiguous reference genomes using PacBio long-read and Omni-C technologies for three species of Passerellidae sparrow. We compared these assemblies to three chromosome-level sparrow assemblies and nine other sparrow assemblies generated using a variety of short- and long-read technologies. All long-read based assemblies were longer (range: 1.12 to 1.41 Gb) than short-read assemblies (0.91 to 1.08 Gb) and assembly length was strongly correlated with the amount of repeat content. Repeat content for Bell's sparrow (31.2% of genome) was the highest level ever reported within the order Passeriformes, which comprises over half of avian diversity. The highest levels of repeat content (79.2% to 93.7%) were found on the W chromosome relative to other regions of the genome. Finally, we show that proliferation of different TE classes varied even among species with similar levels of repeat content. These patterns support a dynamic model of TE expansion and contraction even in a clade where TEs were once thought to be fairly depauperate and static. Our work highlights how the resolution of difficult-to-assemble regions of the genome with new sequencing technologies promises to transform our understanding of avian genome evolution.
Collapse
Affiliation(s)
- Phred M Benham
- Museum of Vertebrate Zoology, University of California Berkeley, Berkeley, CA 94720, USA
- Department of Integrative Biology, University of California Berkeley, Berkeley, CA 94720, USA
| | - Carla Cicero
- Museum of Vertebrate Zoology, University of California Berkeley, Berkeley, CA 94720, USA
| | - Merly Escalona
- Department of Biomolecular Engineering, University of California Santa Cruz, Santa Cruz, CA 95064, USA
| | - Eric Beraut
- Department of Ecology and Evolutionary Biology, University of California, Santa Cruz, Santa Cruz, CA 95064, USA
| | - Colin Fairbairn
- Department of Ecology and Evolutionary Biology, University of California, Santa Cruz, Santa Cruz, CA 95064, USA
| | - Mohan P A Marimuthu
- DNA Technologies and Expression Analysis Core Laboratory, Genome Center, University of California-Davis, Davis, CA 95616, USA
| | - Oanh Nguyen
- DNA Technologies and Expression Analysis Core Laboratory, Genome Center, University of California-Davis, Davis, CA 95616, USA
| | - Ruta Sahasrabudhe
- DNA Technologies and Expression Analysis Core Laboratory, Genome Center, University of California-Davis, Davis, CA 95616, USA
| | - Benjamin L King
- Department of Molecular and Biomedical Sciences, University of Maine, Orono, ME 04469, USA
| | - W Kelley Thomas
- Department of Molecular, Cellular and Biomedical Sciences, University of New Hampshire, Durham, NH 03824, USA
| | - Adrienne I Kovach
- Department of Natural Resources and the Environment, University of New Hampshire, Durham, NH 03824, USA
| | - Michael W Nachman
- Museum of Vertebrate Zoology, University of California Berkeley, Berkeley, CA 94720, USA
- Department of Integrative Biology, University of California Berkeley, Berkeley, CA 94720, USA
| | - Rauri C K Bowie
- Museum of Vertebrate Zoology, University of California Berkeley, Berkeley, CA 94720, USA
- Department of Integrative Biology, University of California Berkeley, Berkeley, CA 94720, USA
| |
Collapse
|
2
|
O’Connor RE, Kretschmer R, Romanov MN, Griffin DK. A Bird's-Eye View of Chromosomic Evolution in the Class Aves. Cells 2024; 13:310. [PMID: 38391923 PMCID: PMC10886771 DOI: 10.3390/cells13040310] [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: 12/05/2023] [Revised: 01/27/2024] [Accepted: 02/05/2024] [Indexed: 02/24/2024] Open
Abstract
Birds (Aves) are the most speciose of terrestrial vertebrates, displaying Class-specific characteristics yet incredible external phenotypic diversity. Critical to agriculture and as model organisms, birds have adapted to many habitats. The only extant examples of dinosaurs, birds emerged ~150 mya and >10% are currently threatened with extinction. This review is a comprehensive overview of avian genome ("chromosomic") organization research based mostly on chromosome painting and BAC-based studies. We discuss traditional and contemporary tools for reliably generating chromosome-level assemblies and analyzing multiple species at a higher resolution and wider phylogenetic distance than previously possible. These results permit more detailed investigations into inter- and intrachromosomal rearrangements, providing unique insights into evolution and speciation mechanisms. The 'signature' avian karyotype likely arose ~250 mya and remained largely unchanged in most groups including extinct dinosaurs. Exceptions include Psittaciformes, Falconiformes, Caprimulgiformes, Cuculiformes, Suliformes, occasional Passeriformes, Ciconiiformes, and Pelecaniformes. The reasons for this remarkable conservation may be the greater diploid chromosome number generating variation (the driver of natural selection) through a greater possible combination of gametes and/or an increase in recombination rate. A deeper understanding of avian genomic structure permits the exploration of fundamental biological questions pertaining to the role of evolutionary breakpoint regions and homologous synteny blocks.
Collapse
Affiliation(s)
- Rebecca E. O’Connor
- School of Biosciences, University of Kent, Canterbury CT2 7NJ, UK; (R.E.O.); (M.N.R.)
| | - Rafael Kretschmer
- Departamento de Ecologia, Zoologia e Genética, Instituto de Biologia, Campus Universitário Capão do Leão, Universidade Federal de Pelotas, Pelotas 96010-900, RS, Brazil;
| | - Michael N. Romanov
- School of Biosciences, University of Kent, Canterbury CT2 7NJ, UK; (R.E.O.); (M.N.R.)
- L. K. Ernst Federal Research Centre for Animal Husbandry, Dubrovitsy, 142132 Podolsk, Moscow Oblast, Russia
| | - Darren K. Griffin
- School of Biosciences, University of Kent, Canterbury CT2 7NJ, UK; (R.E.O.); (M.N.R.)
| |
Collapse
|
3
|
Stuart KC, Johnson RN, Major RE, Atsawawaranunt K, Ewart KM, Rollins LA, Santure AW, Whibley A. The genome of a globally invasive passerine, the common myna, Acridotheres tristis. DNA Res 2024; 31:dsae005. [PMID: 38366840 PMCID: PMC10917472 DOI: 10.1093/dnares/dsae005] [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: 08/24/2023] [Revised: 02/13/2024] [Accepted: 02/15/2024] [Indexed: 02/18/2024] Open
Abstract
In an era of global climate change, biodiversity conservation is receiving increased attention. Conservation efforts are greatly aided by genetic tools and approaches, which seek to understand patterns of genetic diversity and how they impact species health and their ability to persist under future climate regimes. Invasive species offer vital model systems in which to investigate questions regarding adaptive potential, with a particular focus on how changes in genetic diversity and effective population size interact with novel selection regimes. The common myna (Acridotheres tristis) is a globally invasive passerine and is an excellent model species for research both into the persistence of low-diversity populations and the mechanisms of biological invasion. To underpin research on the invasion genetics of this species, we present the genome assembly of the common myna. We describe the genomic landscape of this species, including genome wide allelic diversity, methylation, repeats, and recombination rate, as well as an examination of gene family evolution. Finally, we use demographic analysis to identify that some native regions underwent a dramatic population increase between the two most recent periods of glaciation, and reveal artefactual impacts of genetic bottlenecks on demographic analysis.
Collapse
Affiliation(s)
- Katarina C Stuart
- School of Biological Sciences, University of Auckland, Auckland, Aotearoa, New Zealand
- Evolution and Ecology Research Centre, School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, Australia
| | - Rebecca N Johnson
- National Museum of Natural History, Smithsonian Institution, Washington, DC, USA
| | - Richard E Major
- Australian Museum Research Institute, Australian Museum, Sydney, Australia
| | | | - Kyle M Ewart
- Australian Museum Research Institute, Australian Museum, Sydney, Australia
- School of Life and Environmental Sciences,University of Sydney, Sydney, Australia
| | - Lee A Rollins
- Evolution and Ecology Research Centre, School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, Australia
| | - Anna W Santure
- School of Biological Sciences, University of Auckland, Auckland, Aotearoa, New Zealand
| | - Annabel Whibley
- School of Biological Sciences, University of Auckland, Auckland, Aotearoa, New Zealand
| |
Collapse
|
4
|
Minias P, Edwards SV, Babik W. Ancient duplication, coevolution, and selection at the MHC class IIA and IIB genes of birds. Front Immunol 2023; 14:1250824. [PMID: 37965325 PMCID: PMC10641522 DOI: 10.3389/fimmu.2023.1250824] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Accepted: 10/18/2023] [Indexed: 11/16/2023] Open
Abstract
Introduction The Major Histocompatibility Complex (MHC) of vertebrates is a dynamically evolving multigene family primarily responsible for recognizing non-self peptide antigens and triggering a pathogen-specific adaptive immune response. In birds, the MHC was previously thought to evolve via concerted evolution with high degree of gene homogenization and the rapid loss of orthology. However, the discovery of two ancient avian MHC-IIB gene lineages (DAB1 and DAB2) originating before the radiation of extant birds indicated that despite the action of concerted evolution, orthology may be detectable for long evolutionary periods. Methods Here, we take advantage of rapidly accumulating digital genomic resources to search for the signal of an ancient duplication at the avian MHC-IIA genes, as well as to compare phylogenetic distribution and selection between MHC-IIA and IIB gene lineages. Results The analysis of MHC sequences from over 230 species representing ca. 70 bird families revealed the presence of two ancient MHC-IIA gene lineages (DAA1 and DAA2) and showed that their phylogenetic distribution matches exactly the distribution of DAB1 and DAB2 lineages, suggesting tight coevolution. The early post-duplication divergence of DAA1 and DAA2 was driven by positive selection fixing radical amino acid differences within the membrane-proximal domain and, most probably, being functionally related to the interactions between α2 and β2 chains of the MHC-II heterodimer. We detected no evidence for an overall (gene-wide) relaxation or intensification of selection at either DAA1/DAB1 or DAA2/DAB2, but codon-specific differences in selection signature were found at the peptide-binding sites between the two gene lineages, perhaps implying specialization to different pathogen regimes. Discussion Our results suggest that specific pairing of MHC-II α and β chains may have an adaptive significance, a conclusion that advances knowledge on the macroevolution of the avian MHC-II and opens exciting novel directions for future research.
Collapse
Affiliation(s)
- Piotr Minias
- University of Lodz, Faculty of Biology and Environmental Protection, Department of Biodiversity Studies and Bioeducation, Lodz, Poland
| | - Scott V. Edwards
- Harvard University, Museum of Comparative Zoology, Cambridge, MA, United States
- Harvard University, Department of Organismic and Evolutionary Biology, Cambridge, MA, United States
| | - Wiesław Babik
- Jagiellonian University, Institute of Environmental Sciences, Faculty of Biology, Kraków, Poland
| |
Collapse
|
5
|
Borodin PM. Germline-restricted chromosomes of the songbirds. Vavilovskii Zhurnal Genet Selektsii 2023; 27:641-650. [PMID: 38023808 PMCID: PMC10643108 DOI: 10.18699/vjgb-23-75] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Revised: 06/30/2023] [Accepted: 06/30/2023] [Indexed: 12/01/2023] Open
Abstract
Germline-restricted chromosomes (GRCs) are present in the genomes of germline cells and absent from somatic cells. A GRC is found in all species of the songbirds (Passeri) and in none of the other bird orders studied to date. This indicates that GRC originated in the common ancestor of the songbirds. The germline-restricted chromosome is permanently absent from somatic cells of the songbird, while female germline cells usually contain two copies of GRC and male ones have one copy. In females, GRCs undergo synapsis and restricted recombination in their terminal regions during meiotic prophase. In males, it is almost always eliminated from spermatocytes. Thus, GRC is inherited almost exclusively through the maternal lineage. The germline-restricted chromosome is a necessary genomic element in the germline cells of songbirds. To date, the GRC genetic composition has been studied in four species only. Some GRC genes are actively expressed in female and male gonads, controlling the development of germline cells and synthesis of the proteins involved in the organization of meiotic chromosomes. Songbird species vary in GRC size and genetic composition. The GRC of each bird species consists of amplified and modified copies of genes from the basic genome of that species. The level of homology between GRCs of different species is relatively low, indicating a high rate of genetic evolution of this chromosome. Transmission through the maternal lineage and suppression of the recombination contribute significantly to the accelerated evolution of GRCs. One may suggest that the rapid coordinated evolution between the GRC genes and the genes of the basic genome in the songbirds might be responsible for the explosive speciation and adaptive radiation of this most species-rich and diverse infraorder of birds.
Collapse
Affiliation(s)
- P M Borodin
- Institute of Cytology and Genetics of the Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
| |
Collapse
|
6
|
Pinto BJ, Gamble T, Smith CH, Keating SE, Havird JC, Chiari Y. The revised reference genome of the leopard gecko (Eublepharis macularius) provides insight into the considerations of genome phasing and assembly. J Hered 2023; 114:513-520. [PMID: 36869788 PMCID: PMC10445513 DOI: 10.1093/jhered/esad016] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Accepted: 02/28/2023] [Indexed: 03/05/2023] Open
Abstract
Genomic resources across squamate reptiles (lizards and snakes) have lagged behind other vertebrate systems and high-quality reference genomes remain scarce. Of the 23 chromosome-scale reference genomes across the order, only 12 of the ~60 squamate families are represented. Within geckos (infraorder Gekkota), a species-rich clade of lizards, chromosome-level genomes are exceptionally sparse representing only two of the seven extant families. Using the latest advances in genome sequencing and assembly methods, we generated one of the highest-quality squamate genomes to date for the leopard gecko, Eublepharis macularius (Eublepharidae). We compared this assembly to the previous, short-read only, E. macularius reference genome published in 2016 and examined potential factors within the assembly influencing contiguity of genome assemblies using PacBio HiFi data. Briefly, the read N50 of the PacBio HiFi reads generated for this study was equal to the contig N50 of the previous E. macularius reference genome at 20.4 kilobases. The HiFi reads were assembled into a total of 132 contigs, which was further scaffolded using HiC data into 75 total sequences representing all 19 chromosomes. We identified 9 of the 19 chromosomal scaffolds were assembled as a near-single contig, whereas the other 10 chromosomes were each scaffolded together from multiple contigs. We qualitatively identified that the percent repeat content within a chromosome broadly affects its assembly contiguity prior to scaffolding. This genome assembly signifies a new age for squamate genomics where high-quality reference genomes rivaling some of the best vertebrate genome assemblies can be generated for a fraction of previous cost estimates. This new E. macularius reference assembly is available on NCBI at JAOPLA010000000.
Collapse
Affiliation(s)
- Brendan J Pinto
- School of Life Sciences, Arizona State University, Tempe, AZ, USA
- Center for Evolution and Medicine, Arizona State University, Tempe, AZ, USA
- Department of Zoology, Milwaukee Public Museum, Milwaukee, WI, USA
| | - Tony Gamble
- Department of Zoology, Milwaukee Public Museum, Milwaukee, WI, USA
- Department of Biological Sciences, Marquette University, Milwaukee WI, USA
- Bell Museum of Natural History, University of Minnesota, St Paul, MN, USA
| | - Chase H Smith
- Department of Integrative Biology, University of Texas at Austin, Austin, TX, USA
| | - Shannon E Keating
- Department of Biological Sciences, Marquette University, Milwaukee WI, USA
| | - Justin C Havird
- Department of Integrative Biology, University of Texas at Austin, Austin, TX, USA
| | - Ylenia Chiari
- Department of Biology, George Mason University, Fairfax, VA, USA
| |
Collapse
|
7
|
Benham PM, Cicero C, DeRaad DA, McCormack JE, Wayne RK, Escalona M, Beraut E, Marimuthu MPA, Nguyen O, Nachman MW, Bowie RCK. A highly contiguous reference genome for the Steller's jay (Cyanocitta stelleri). J Hered 2023; 114:549-560. [PMID: 37395718 PMCID: PMC10445514 DOI: 10.1093/jhered/esad042] [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: 04/14/2023] [Accepted: 06/29/2023] [Indexed: 07/04/2023] Open
Abstract
The Steller's jay is a familiar bird of western forests from Alaska south to Nicaragua. Here, we report a draft reference assembly for the species generated from PacBio HiFi long-read and Omni-C chromatin-proximity sequencing data as part of the California Conservation Genomics Project (CCGP). Sequenced reads were assembled into 352 scaffolds totaling 1.16 Gb in length. Assembly metrics indicate a highly contiguous and complete assembly with a contig N50 of 7.8 Mb, scaffold N50 of 25.8 Mb, and BUSCO completeness score of 97.2%. Repetitive elements span 16.6% of the genome including nearly 90% of the W chromosome. Compared with high-quality assemblies from other members of the family Corvidae, the Steller's jay genome contains a larger proportion of repetitive elements than 4 crow species (Corvus), but a lower proportion of repetitive elements than the California scrub-jay (Aphelocoma californica). This reference genome will serve as an essential resource for future studies on speciation, local adaptation, phylogeography, and conservation genetics in this species of significant biological interest.
Collapse
Affiliation(s)
- Phred M Benham
- Museum of Vertebrate Zoology, University of California Berkeley, Berkeley, CA, United States
- Department of Integrative Biology, University of California Berkeley, Berkeley, CA, United States
| | - Carla Cicero
- Museum of Vertebrate Zoology, University of California Berkeley, Berkeley, CA, United States
| | - Devon A DeRaad
- Biodiversity Institute and Department of Ecology and Evolutionary Biology, University of Kansas, Lawrence, KS, United States
| | - John E McCormack
- Moore Laboratory of Zoology, Occidental College, Los Angeles, CA, United States
| | - Robert K Wayne
- Department of Ecology and Evolutionary Biology, University of California, Los Angeles, Los Angeles, CA, United States
| | - Merly Escalona
- Department of Biomolecular Engineering, University of California Santa Cruz, Santa Cruz, CA, United States
| | - Eric Beraut
- Department of Ecology and Evolutionary Biology, University of California, Santa Cruz, Santa Cruz, CA, United States
| | - Mohan P A Marimuthu
- DNA Technologies and Expression Analysis Core Laboratory, Genome Center, University of California-Davis, Davis, CA, United States
| | - Oanh Nguyen
- DNA Technologies and Expression Analysis Core Laboratory, Genome Center, University of California-Davis, Davis, CA, United States
| | - Michael W Nachman
- Museum of Vertebrate Zoology, University of California Berkeley, Berkeley, CA, United States
- Department of Integrative Biology, University of California Berkeley, Berkeley, CA, United States
| | - Rauri C K Bowie
- Museum of Vertebrate Zoology, University of California Berkeley, Berkeley, CA, United States
- Department of Integrative Biology, University of California Berkeley, Berkeley, CA, United States
| |
Collapse
|
8
|
Pinto BJ, Gamble T, Smith CH, Wilson MA. A lizard is never late: Squamate genomics as a recent catalyst for understanding sex chromosome and microchromosome evolution. J Hered 2023; 114:445-458. [PMID: 37018459 PMCID: PMC10445521 DOI: 10.1093/jhered/esad023] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Accepted: 04/03/2023] [Indexed: 04/07/2023] Open
Abstract
In 2011, the first high-quality genome assembly of a squamate reptile (lizard or snake) was published for the green anole. Dozens of genome assemblies were subsequently published over the next decade, yet these assemblies were largely inadequate for answering fundamental questions regarding genome evolution in squamates due to their lack of contiguity or annotation. As the "genomics age" was beginning to hit its stride in many organismal study systems, progress in squamates was largely stagnant following the publication of the green anole genome. In fact, zero high-quality (chromosome-level) squamate genomes were published between the years 2012 and 2017. However, since 2018, an exponential increase in high-quality genome assemblies has materialized with 24 additional high-quality genomes published for species across the squamate tree of life. As the field of squamate genomics is rapidly evolving, we provide a systematic review from an evolutionary genomics perspective. We collated a near-complete list of publicly available squamate genome assemblies from more than half-a-dozen international and third-party repositories and systematically evaluated them with regard to their overall quality, phylogenetic breadth, and usefulness for continuing to provide accurate and efficient insights into genome evolution across squamate reptiles. This review both highlights and catalogs the currently available genomic resources in squamates and their ability to address broader questions in vertebrates, specifically sex chromosome and microchromosome evolution, while addressing why squamates may have received less historical focus and has caused their progress in genomics to lag behind peer taxa.
Collapse
Affiliation(s)
- Brendan J Pinto
- School of Life Sciences, Arizona State University, Tempe, AZ, United States
- Center for Evolution and Medicine, Arizona State University, Tempe, AZ, United States
- Department of Zoology, Milwaukee Public Museum, Milwaukee, WI, United States
| | - Tony Gamble
- Department of Zoology, Milwaukee Public Museum, Milwaukee, WI, United States
- Department of Biological Sciences, Marquette University, Milwaukee, WI, United States
- Bell Museum of Natural History, University of Minnesota, St Paul, MN, United States
| | - Chase H Smith
- Department of Integrative Biology, University of Texas at Austin, Austin, TX, United States
| | - Melissa A Wilson
- School of Life Sciences, Arizona State University, Tempe, AZ, United States
- Center for Evolution and Medicine, Arizona State University, Tempe, AZ, United States
- Center for Mechanisms of Evolution, Biodesign Institute, Tempe, AZ, United States
| |
Collapse
|
9
|
Luo H, Jiang X, Li B, Wu J, Shen J, Xu Z, Zhou X, Hou M, Huang Z, Ou X, Xu L. A high-quality genome assembly highlights the evolutionary history of the great bustard (Otis tarda, Otidiformes). Commun Biol 2023; 6:746. [PMID: 37463976 PMCID: PMC10354230 DOI: 10.1038/s42003-023-05137-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Accepted: 07/11/2023] [Indexed: 07/20/2023] Open
Abstract
Conservation genomics often relies on non-invasive methods to obtain DNA fragments which limit the power of multi-omic analyses for threatened species. Here, we report multi-omic analyses based on a well-preserved great bustard individual (Otis tarda, Otidiformes) that was found dead in the mountainous region in Gansu, China. We generate a near-complete genome assembly containing only 18 gaps scattering in 8 out of the 40 assembled chromosomes. We characterize the DNA methylation landscape which is correlated with GC content and gene expression. Our phylogenomic analysis suggests Otidiformes and Musophagiformes are sister groups that diverged from each other 46.3 million years ago. The genetic diversity of great bustard is found the lowest among the four available Otidiformes genomes, possibly due to population declines during past glacial periods. As one of the heaviest migratory birds, great bustard possesses several expanded gene families related to cardiac contraction, actin contraction, calcium ion signaling transduction, as well as positively selected genes enriched for metabolism. Finally, we identify an extremely young evolutionary stratum on the sex chromosome, a rare case among birds. Together, our study provides insights into the conservation genomics, adaption and chromosome evolution of the great bustard.
Collapse
Affiliation(s)
- Haoran Luo
- MOE Key Laboratory of Freshwater Fish Reproduction and Development, Key Laboratory of Aquatic Science of Chongqing, School of Life Sciences, Southwest University, Chongqing, 400715, China
- Key Laboratory of Ministry of Education for the Coastal and Wetland Ecosystems, College of the Environment and Ecology, Xiamen University, Xiamen, 361102, China
| | - Xinrui Jiang
- MOE Key Laboratory of Freshwater Fish Reproduction and Development, Key Laboratory of Aquatic Science of Chongqing, School of Life Sciences, Southwest University, Chongqing, 400715, China
| | - Boping Li
- Gansu Key Laboratory of Protection and Utilization for Biological Resources and Ecological Restoration, Longdong University, Qingyang, Gansu Province, 745000, China
| | - Jiahong Wu
- MOE Key Laboratory of Freshwater Fish Reproduction and Development, Key Laboratory of Aquatic Science of Chongqing, School of Life Sciences, Southwest University, Chongqing, 400715, China
| | - Jiexin Shen
- MOE Key Laboratory of Freshwater Fish Reproduction and Development, Key Laboratory of Aquatic Science of Chongqing, School of Life Sciences, Southwest University, Chongqing, 400715, China
| | - Zaoxu Xu
- Gansu Key Laboratory of Protection and Utilization for Biological Resources and Ecological Restoration, Longdong University, Qingyang, Gansu Province, 745000, China
| | - Xiaoping Zhou
- Key Laboratory of Ministry of Education for the Coastal and Wetland Ecosystems, College of the Environment and Ecology, Xiamen University, Xiamen, 361102, China
| | - Minghao Hou
- Gansu Key Laboratory of Protection and Utilization for Biological Resources and Ecological Restoration, Longdong University, Qingyang, Gansu Province, 745000, China
| | - Zhen Huang
- Fujian-Macao Science and Technology Cooperation Base of Traditional Chinese Medicine-Oriented Chronic Disease Prevention and Treatment, Innovation and Transformation Center, Fujian University of Traditional Chinese Medicine, Fuzhou, 350108, China.
- Fujian Key Laboratory of Developmental and Neural Biology, College of Life Sciences, Fujian Normal University, Fuzhou, 350117, China.
| | - Xiaobin Ou
- Gansu Key Laboratory of Protection and Utilization for Biological Resources and Ecological Restoration, Longdong University, Qingyang, Gansu Province, 745000, China.
| | - Luohao Xu
- MOE Key Laboratory of Freshwater Fish Reproduction and Development, Key Laboratory of Aquatic Science of Chongqing, School of Life Sciences, Southwest University, Chongqing, 400715, China.
| |
Collapse
|
10
|
Johnson JA, Athrey G, Anderson CM, Bell DA, Dixon A, Kumazawa Y, Maechtle T, Meeks GW, Mindell D, Nakajima K, Novak B, Talbot S, White C, Zhan X. Whole-genome survey reveals extensive variation in genetic diversity and inbreeding levels among peregrine falcon subspecies. Ecol Evol 2023; 13:e10347. [PMID: 37484928 PMCID: PMC10361364 DOI: 10.1002/ece3.10347] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2023] [Revised: 07/04/2023] [Accepted: 07/10/2023] [Indexed: 07/25/2023] Open
Abstract
In efforts to prevent extinction, resource managers are often tasked with increasing genetic diversity in a population of concern to prevent inbreeding depression or improve adaptive potential in a changing environment. The assumption that all small populations require measures to increase their genetic diversity may be unwarranted, and limited resources for conservation may be better utilized elsewhere. We test this assumption in a case study focused on the peregrine falcon (Falco peregrinus), a cosmopolitan circumpolar species with 19 named subspecies. We used whole-genome resequencing to generate over two million single nucleotide polymorphisms (SNPs) from multiple individuals of all peregrine falcon subspecies. Our analyses revealed extensive variation among subspecies, with many island-restricted and nonmigratory populations possessing lower overall genomic diversity, elevated inbreeding coefficients (F ROH)-among the highest reported, and extensive runs of homozygosity (ROH) compared to mainland and migratory populations. Similarly, the majority of subspecies that are either nonmigratory or restricted to islands show a much longer history of low effective population size (N e). While mutational load analyses indicated an increased proportion of homozygous-derived deleterious variants (i.e., drift load) among nonmigrant and island populations compared to those that are migrant or reside on the mainland, no significant differences in the proportion of heterozygous deleterious variants (i.e., inbreeding load) was observed. Our results provide evidence that high levels of inbreeding may not be an existential threat for some populations or taxa. Additional factors such as the timing and severity of population declines are important to consider in management decisions about extinction potential.
Collapse
Affiliation(s)
- Jeff A. Johnson
- Department of Biological SciencesUniversity of North TexasDentonTexasUSA
- Wolf Creek Operating FoundationWolfWyomingUSA
| | - Giridhar Athrey
- Department of Poultry Science & Faculty of Ecology and Evolutionary BiologyTexas A&M UniversityCollege StationTexasUSA
| | | | - Douglas A. Bell
- East Bay Regional Park DistrictOaklandCaliforniaUSA
- California Academy of SciencesSan FranciscoCaliforniaUSA
| | - Andrew Dixon
- The Mohamed Bin Zayed Raptor Conservation FundAbu DhabiUnited Arab Emirates
- International Wildlife ConsultantsCarmarthenUK
| | - Yoshinori Kumazawa
- Research Center for Biological DiversityNagoya City UniversityNagoyaJapan
| | | | - Garrett W. Meeks
- Department of Biological SciencesUniversity of North TexasDentonTexasUSA
| | - David Mindell
- Museum of Vertebrate ZoologyUniversity of California, BerkeleyBerkeleyCaliforniaUSA
| | - Keiya Nakajima
- Research Center for Biological DiversityNagoya City UniversityNagoyaJapan
- The Japan Falconiformes CenterOwariasahiJapan
| | - Ben Novak
- Revive & RestoreSausalitoCaliforniaUSA
| | - Sandra Talbot
- Far Northwestern Institute of Art and ScienceAnchorageAlaskaUSA
| | | | | |
Collapse
|
11
|
Benham PM, Cicero C, Escalona M, Beraut E, Marimuthu MPA, Nguyen O, Nachman MW, Bowie RCK. A highly contiguous genome assembly for the California quail (Callipepla californica). J Hered 2023; 114:418-427. [PMID: 36763048 PMCID: PMC10287149 DOI: 10.1093/jhered/esad008] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Accepted: 02/09/2023] [Indexed: 02/11/2023] Open
Abstract
The California quail (Callipepla californica) is an iconic native bird of scrub and oak woodlands in California and the Baja Peninsula of Mexico. Here, we report a draft reference assembly for the species generated from PacBio HiFi long read and Omni-C chromatin-proximity sequencing data as part of the California Conservation Genomics Project (CCGP). Sequenced reads were assembled into 321 scaffolds totaling 1.08 Gb in length. Assembly metrics indicate a highly contiguous and complete assembly with a contig N50 of 5.5 Mb, scaffold N50 of 19.4 Mb, and BUSCO completeness score of 96.5%. Transposable elements (TEs) occupy 16.5% of the genome, more than previous Odontophoridae quail assemblies but in line with estimates of TE content for recent long-read assemblies of chicken and Peking duck. Together these metrics indicate that the present assembly is more complete than prior reference assemblies generated for Odontophoridae quail. This reference will serve as an essential resource for studies on local adaptation, phylogeography, and conservation genetics in this species of significant biological and recreational interest.
Collapse
Affiliation(s)
- Phred M Benham
- Museum of Vertebrate Zoology, University of California Berkeley, Berkeley, CA, United States
- Department of Integrative Biology, University of California Berkeley, Berkeley, CA, United States
| | - Carla Cicero
- Museum of Vertebrate Zoology, University of California Berkeley, Berkeley, CA, United States
| | - Merly Escalona
- Department of Biomolecular Engineering, University of California Santa Cruz, Santa Cruz, CA, United States
| | - Eric Beraut
- Department of Ecology and Evolutionary Biology, University of California, Santa Cruz, Santa Cruz, CA, United States
- Museum of Vertebrate Zoology, University of California Berkeley, Berkeley, CA, United States
| | - Mohan P A Marimuthu
- DNA Technologies and Expression Analysis Core Laboratory, Genome Center, University of California-Davis, Davis, CA, United States
- Museum of Vertebrate Zoology, University of California Berkeley, Berkeley, CA, United States
| | - Oanh Nguyen
- DNA Technologies and Expression Analysis Core Laboratory, Genome Center, University of California-Davis, Davis, CA, United States
- Museum of Vertebrate Zoology, University of California Berkeley, Berkeley, CA, United States
| | - Michael W Nachman
- Museum of Vertebrate Zoology, University of California Berkeley, Berkeley, CA, United States
- Department of Integrative Biology, University of California Berkeley, Berkeley, CA, United States
| | - Rauri C K Bowie
- Museum of Vertebrate Zoology, University of California Berkeley, Berkeley, CA, United States
- Department of Integrative Biology, University of California Berkeley, Berkeley, CA, United States
| |
Collapse
|
12
|
Pinto BJ, Gamble T, Smith CH, Wilson MA. A lizard is never late: squamate genomics as a recent catalyst for understanding sex chromosome and microchromosome evolution. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.20.524006. [PMID: 37034614 PMCID: PMC10081179 DOI: 10.1101/2023.01.20.524006] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
In 2011, the first high-quality genome assembly of a squamate reptile (lizard or snake) was published for the green anole. Dozens of genome assemblies were subsequently published over the next decade, yet these assemblies were largely inadequate for answering fundamental questions regarding genome evolution in squamates due to their lack of contiguity or annotation. As the "genomics age" was beginning to hit its stride in many organismal study systems, progress in squamates was largely stagnant following the publication of the green anole genome. In fact, zero high-quality (chromosome-level) squamate genomes were published between the years 2012-2017. However, since 2018, an exponential increase in high-quality genome assemblies has materialized with 24 additional high-quality genomes published for species across the squamate tree of life. As the field of squamate genomics is rapidly evolving, we provide a systematic review from an evolutionary genomics perspective. We collated a near-complete list of publicly available squamate genome assemblies from more than half-a-dozen international and third-party repositories and systematically evaluated them with regard to their overall quality, phylogenetic breadth, and usefulness for continuing to provide accurate and efficient insights into genome evolution across squamate reptiles. This review both highlights and catalogs the currently available genomic resources in squamates and their ability to address broader questions in vertebrates, specifically sex chromosome and microchromosome evolution, while addressing why squamates may have received less historical focus and has caused their progress in genomics to lag behind peer taxa.
Collapse
Affiliation(s)
- Brendan J Pinto
- School of Life Sciences, Arizona State University, Tempe, AZ USA
- Center for Evolution and Medicine, Arizona State University, Tempe, AZ USA
- Department of Zoology, Milwaukee Public Museum, Milwaukee, WI USA
| | - Tony Gamble
- Department of Zoology, Milwaukee Public Museum, Milwaukee, WI USA
- Department of Biological Sciences, Marquette University, Milwaukee WI USA
- Bell Museum of Natural History, University of Minnesota, St Paul, MN USA
| | - Chase H Smith
- Department of Integrative Biology, University of Texas at Austin, Austin, TX, USA
| | - Melissa A Wilson
- School of Life Sciences, Arizona State University, Tempe, AZ USA
- Center for Evolution and Medicine, Arizona State University, Tempe, AZ USA
- Center for Mechanisms of Evolution, Biodesign Institute, Tempe, AZ USA
| |
Collapse
|
13
|
Zuccolo A, Mfarrej S, Celii M, Mussurova S, Rivera LF, Llaca V, Mohammed N, Pain A, Alrefaei AF, Alrefaei AF, Wing RA. The gyrfalcon (Falco rusticolus) genome. G3 (BETHESDA, MD.) 2023; 13:6972330. [PMID: 36611193 PMCID: PMC9997569 DOI: 10.1093/g3journal/jkad001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Revised: 12/22/2022] [Accepted: 12/26/2022] [Indexed: 01/09/2023]
Abstract
High-quality genome assemblies are characterized by high-sequence contiguity, completeness, and a low error rate, thus providing the basis for a wide array of studies focusing on natural species ecology, conservation, evolution, and population genomics. To provide this valuable resource for conservation projects and comparative genomics studies on gyrfalcon (Falco rusticolus), we sequenced and assembled the genome of this species using third-generation sequencing strategies and optical maps. Here, we describe a highly contiguous and complete genome assembly comprising 20 scaffolds and 13 contigs with a total size of 1.193 Gbp, including 8,064 complete Benchmarking Universal Single-Copy Orthologs (BUSCOs) of the total 8,338 BUSCO groups present in the library aves_odb10. Of these BUSCO genes, 96.7% were complete, 96.1% were present as a single copy, and 0.6% were duplicated. Furthermore, 0.8% of BUSCO genes were fragmented and 2.5% (210) were missing. A de novo search for transposable elements (TEs) identified 5,716 TEs that masked 7.61% of the F. rusticolus genome assembly when combined with publicly available TE collections. Long interspersed nuclear elements, in particular, the element Chicken-repeat 1 (CR1), were the most abundant TEs in the F. rusticolus genome. A de novo first-pass gene annotation was performed using 293,349 PacBio Iso-Seq transcripts and 496,195 transcripts derived from the assembly of 42,429,525 Illumina PE RNA-seq reads. In all, 19,602 putative genes, of which 59.31% were functionally characterized and associated with Gene Ontology terms, were annotated. A comparison of the gyrfalcon genome assembly with the publicly available assemblies of the domestic chicken (Gallus gallus), zebra finch (Taeniopygia guttata), and hummingbird (Calypte anna) revealed several genome rearrangements. In particular, nine putative chromosome fusions were identified in the gyrfalcon genome assembly compared with those in the G. gallus genome assembly. This genome assembly, its annotation for TEs and genes, and the comparative analyses presented, complement and strength the base of high-quality genome assemblies and associated resources available for comparative studies focusing on the evolution, ecology, and conservation of Aves.
Collapse
Affiliation(s)
- Andrea Zuccolo
- Center for Desert Agriculture (CDA), Biological and Environmental Sciences & Engineering Division (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia.,Crop Science Research Center, Sant'Anna School of Advanced Studies, Piazza Martiri della Libertà 33, 56127 Pisa, Italy
| | - Sara Mfarrej
- King Abdullah University of Science and Technology (KAUST), Pathogen Genomics Laboratory, Biological and Environmental Science and Engineering (BESE), Thuwal-Jeddah 23955-6900, Saudi Arabia
| | - Mirko Celii
- Center for Desert Agriculture (CDA), Biological and Environmental Sciences & Engineering Division (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
| | - Saule Mussurova
- Center for Desert Agriculture (CDA), Biological and Environmental Sciences & Engineering Division (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
| | - Luis F Rivera
- Center for Desert Agriculture (CDA), Biological and Environmental Sciences & Engineering Division (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
| | - Victor Llaca
- Research and Development, Corteva Agriscience, Johnston, IA 50131, USA
| | - Nahed Mohammed
- Center for Desert Agriculture (CDA), Biological and Environmental Sciences & Engineering Division (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
| | - Arnab Pain
- King Abdullah University of Science and Technology (KAUST), Pathogen Genomics Laboratory, Biological and Environmental Science and Engineering (BESE), Thuwal-Jeddah 23955-6900, Saudi Arabia
| | | | - Abdulwahed Fahad Alrefaei
- Department of Zoology, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia
| | - Rod A Wing
- Center for Desert Agriculture (CDA), Biological and Environmental Sciences & Engineering Division (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia.,School of Plant Sciences, Arizona Genomics Institute, University of Arizona, 24 Tucson, Arizona 85721, USA
| |
Collapse
|
14
|
Burley JT, Orzechowski SCM, Sin SYW, Edwards SV. Whole-genome phylogeography of the blue-faced honeyeater (Entomyzon cyanotis) and discovery and characterization of a neo-Z chromosome. Mol Ecol 2023; 32:1248-1270. [PMID: 35797346 DOI: 10.1111/mec.16604] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2022] [Revised: 06/22/2022] [Accepted: 07/04/2022] [Indexed: 11/28/2022]
Abstract
Whole-genome surveys of genetic diversity and geographic variation often yield unexpected discoveries of novel structural variation, which long-read DNA sequencing can help clarify. Here, we report on whole-genome phylogeography of a bird exhibiting classic vicariant geographies across Australia and New Guinea, the blue-faced honeyeater (Entomyzon cyanotis), and the discovery and characterization of a novel neo-Z chromosome by long-read sequencing. Using short-read genome-wide SNPs, we inferred population divergence events within E. cyanotis across the Carpentarian and other biogeographic barriers during the Pleistocene (~0.3-1.7 Ma). Evidence for introgression between nonsister populations supports a hypothesis of reticulate evolution around a triad of dynamic barriers around Pleistocene Lake Carpentaria between Australia and New Guinea. During this phylogeographic survey, we discovered a large (134 Mbp) neo-Z chromosome and we explored its diversity, divergence and introgression landscape. We show that, as in some sylvioid passerine birds, a fusion occurred between chromosome 5 and the Z chromosome to form a neo-Z chromosome; and in E. cyanotis, the ancestral pseudoautosomal region (PAR) appears nonrecombinant between Z and W, along with most of the fused chromosome 5. The added recombination-suppressed portion of the neo-Z (~37.2 Mbp) displays reduced diversity and faster population genetic differentiation compared with the ancestral-Z. Yet, the new PAR (~17.4 Mbp) shows elevated diversity and reduced differentiation compared to autosomes, potentially resulting from introgression. In our case, long-read sequencing helped clarify the genomic landscape of population divergence on autosomes and sex chromosomes in a species where prior knowledge of genome structure was still incomplete.
Collapse
Affiliation(s)
- John T Burley
- Museum of Comparative Zoology, Harvard University, Cambridge, Massachusetts, USA.,Department of Evolutionary Biology, Evolutionary Biology Centre (EBC), Uppsala University, Uppsala, Sweden.,Department of Ecology Evolution and Organismal Biology, Brown University, Providence, Rhode Island, USA.,Institute at Brown for Environment and Society, Brown University, Providence, Rhode Island, USA
| | | | - Simon Yung Wa Sin
- Museum of Comparative Zoology, Harvard University, Cambridge, Massachusetts, USA.,School of Biological Sciences, The University of Hong Kong, Hong Kong SAR, China
| | - Scott V Edwards
- Museum of Comparative Zoology, Harvard University, Cambridge, Massachusetts, USA
| |
Collapse
|
15
|
Genome Evolution and the Future of Phylogenomics of Non-Avian Reptiles. Animals (Basel) 2023; 13:ani13030471. [PMID: 36766360 PMCID: PMC9913427 DOI: 10.3390/ani13030471] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Revised: 01/13/2023] [Accepted: 01/15/2023] [Indexed: 02/01/2023] Open
Abstract
Non-avian reptiles comprise a large proportion of amniote vertebrate diversity, with squamate reptiles-lizards and snakes-recently overtaking birds as the most species-rich tetrapod radiation. Despite displaying an extraordinary diversity of phenotypic and genomic traits, genomic resources in non-avian reptiles have accumulated more slowly than they have in mammals and birds, the remaining amniotes. Here we review the remarkable natural history of non-avian reptiles, with a focus on the physical traits, genomic characteristics, and sequence compositional patterns that comprise key axes of variation across amniotes. We argue that the high evolutionary diversity of non-avian reptiles can fuel a new generation of whole-genome phylogenomic analyses. A survey of phylogenetic investigations in non-avian reptiles shows that sequence capture-based approaches are the most commonly used, with studies of markers known as ultraconserved elements (UCEs) especially well represented. However, many other types of markers exist and are increasingly being mined from genome assemblies in silico, including some with greater information potential than UCEs for certain investigations. We discuss the importance of high-quality genomic resources and methods for bioinformatically extracting a range of marker sets from genome assemblies. Finally, we encourage herpetologists working in genomics, genetics, evolutionary biology, and other fields to work collectively towards building genomic resources for non-avian reptiles, especially squamates, that rival those already in place for mammals and birds. Overall, the development of this cross-amniote phylogenomic tree of life will contribute to illuminate interesting dimensions of biodiversity across non-avian reptiles and broader amniotes.
Collapse
|
16
|
Idoko-Akoh A, McGrew MJ. Generation of Genome-Edited Chicken Through Targeting of Primordial Germ Cells. Methods Mol Biol 2023; 2631:419-441. [PMID: 36995681 DOI: 10.1007/978-1-0716-2990-1_20] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/31/2023]
Abstract
Genome editing technology facilitates the creation of specific and precise genetic changes to unravel gene function and rapidly transfer unique alleles between chicken breeds in contrast to lengthy traditional crossbreeding methods for the study of poultry genetics. Innovations in genome sequencing technology have made it possible to map polymorphisms associated with both monogenic and multigenic traits in livestock species. We, and many others, have demonstrated the use of genome editing to introduce specific monogenic traits in chicken through targeting of cultured primordial germ cells. In this chapter, we describe materials and protocols for performing heritable genome editing in the chicken through targeting of in vitro propagated chicken primordial germ cells.
Collapse
Affiliation(s)
- Alewo Idoko-Akoh
- The Roslin Institute & Royal (Dick) School of Veterinary Studies, University of Edinburgh, Midlothian, UK
| | - Michael J McGrew
- The Roslin Institute & Royal (Dick) School of Veterinary Studies, University of Edinburgh, Midlothian, UK.
| |
Collapse
|
17
|
Campagna L, Toews DP. The genomics of adaptation in birds. Curr Biol 2022; 32:R1173-R1186. [DOI: 10.1016/j.cub.2022.07.076] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
18
|
Černý D, Natale R. Comprehensive taxon sampling and vetted fossils help clarify the time tree of shorebirds (Aves, Charadriiformes). Mol Phylogenet Evol 2022; 177:107620. [PMID: 36038056 DOI: 10.1016/j.ympev.2022.107620] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Revised: 06/03/2022] [Accepted: 08/17/2022] [Indexed: 01/20/2023]
Abstract
Shorebirds (Charadriiformes) are a globally distributed clade of modern birds and, due to their ecological and morphological disparity, a frequent subject of comparative studies. While molecular phylogenies have been key to establishing the suprafamilial backbone of the charadriiform tree, a number of relationships at both deep and shallow taxonomic levels remain poorly resolved. The timescale of shorebird evolution also remains uncertain as a result of extensive disagreements among the published divergence dating studies, stemming largely from different choices of fossil calibrations. Here, we present the most comprehensive non-supertree phylogeny of shorebirds to date, based on a total-evidence dataset comprising 353 ingroup taxa (90% of all extant or recently extinct species), 27 loci (15 mitochondrial and 12 nuclear), and 69 morphological characters. We further clarify the timeline of charadriiform evolution by time-scaling this phylogeny using a set of 14 up-to-date and thoroughly vetted fossil calibrations. In addition, we assemble a taxonomically restricted 100-locus dataset specifically designed to resolve outstanding problems in higher-level charadriiform phylogeny. In terms of tree topology, our results are largely congruent with previous studies but indicate that some of the conflicts among earlier analyses reflect a genuine signal of pervasive gene tree discordance. Monophyly of the plovers (Charadriidae), the position of the ibisbill (Ibidorhyncha), and the relationships among the five subfamilies of the gulls (Laridae) could not be resolved even with greatly increased locus and taxon sampling. Moreover, several localized regions of uncertainty persist in shallower parts of the tree, including the interrelationships of the true auks (Alcinae) and anarhynchine plovers. Our node-dating and macroevolutionary rate analyses find support for a Paleocene origin of crown-group shorebirds, as well as exceptionally rapid recent radiations of Old World oystercatchers (Haematopodidae) and select genera of gulls. Our study underscores the challenges involved in estimating a comprehensively sampled and carefully calibrated time tree for a diverse avian clade, and highlights areas in need of further research.
Collapse
Affiliation(s)
- David Černý
- Department of the Geophysical Sciences, University of Chicago, Chicago 60637, USA.
| | - Rossy Natale
- Department of Organismal Biology & Anatomy, University of Chicago, Chicago 60637, USA
| |
Collapse
|
19
|
Hu T, Chen G, Xu Z, Luo S, Wang H, Li C, Shan L, Zhang B. De Novo Whole-Genome Sequencing and Assembly of the Yellow-Throated Bunting (Emberiza elegans) Provides Insights into Its Evolutionary Adaptation. Animals (Basel) 2022; 12:ani12152004. [PMID: 35953992 PMCID: PMC9367368 DOI: 10.3390/ani12152004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Revised: 07/06/2022] [Accepted: 08/04/2022] [Indexed: 11/16/2022] Open
Abstract
Simple Summary We report the genomic sequence of Emberiza elegans for understanding the evolutionary mechanisms of environmental adaptation and for studying a more effective genetic monitoring of this species. The E. elegans assembly was approximately 1.14 Gb, with a scaffold N50 of 28.94 Mb. About 15,868 protein-coding genes were predicted, and 16.62% of the genome was identified as having repetitive elements. Our genomic evolution analyses found considerable numbers of adaptive genes that may help the yellow-throated bunting cope with migratory behavior and environmental stressors of diseases. These results provide us with new insights into genomic evolution and adaptation, thus providing a valuable resource for further studies of population genetic diversity and genome evolution in this species. Abstract Yellow-throated bunting is a small migratory songbird unique to the Palearctic region. However, the genetic studies of this species remain limited, with no nuclear genomic sequence reported to date. In this study, the genomic DNA from the bird was sequenced in long reads using Nanopore sequencing technology. Combining short-read sequencing, the genome was well-assembled and annotated. The final length of the assembly is approximately 1.14 Gb, with a scaffold N50 of 28.94 Mb. About 15,868 protein-coding genes were predicted, and 16.62% of the genome was identified as having repetitive elements. Comparative genomic analysis showed numerous expanded gene families and positively selected genes significantly enriched in those KEGG pathways that are associated with migratory behavior adaptation and immune response. Here, this newly generated de novo genome of the yellow-throated bunting using long reads provide the research community with a valuable resource for further studies of population genetic diversity and genome evolution in this species.
Collapse
Affiliation(s)
- Tingli Hu
- School of Life Sciences, Anhui University, Hefei 230601, China
| | - Guotao Chen
- School of Life Sciences, Anhui University, Hefei 230601, China
| | - Zhen Xu
- School of Life Sciences, Anhui University, Hefei 230601, China
| | - Site Luo
- School of Life Sciences, Xiamen University, Xiamen 361102, China
| | - Hui Wang
- College of Food and Bioengineering, Bengbu University, Bengbu 233030, China
| | - Chunlin Li
- School of Resources and Environmental Engineering, Anhui University, Hefei 230601, China
| | - Lei Shan
- School of Life Sciences, Nanjing Normal University, Nanjing 210023, China
- Correspondence: (L.S.); (B.Z.)
| | - Baowei Zhang
- School of Life Sciences, Anhui University, Hefei 230601, China
- Correspondence: (L.S.); (B.Z.)
| |
Collapse
|
20
|
Establishment of the Primary Avian Gonadal Somatic Cell Lines for Cytogenetic Studies. Animals (Basel) 2022; 12:ani12131724. [PMID: 35804624 PMCID: PMC9264790 DOI: 10.3390/ani12131724] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Revised: 06/29/2022] [Accepted: 07/02/2022] [Indexed: 12/01/2022] Open
Abstract
Simple Summary We developed a simple method for primary somatic cell culture establishment from the ovaries of the great tits and testes of ten Passerine species. The ovary-derived cell cultures were cultivated until the tenth passage without any noticeable decrease in their proliferative activity, while testis-derived cell cultures demonstrated a decreased proliferation potential. However, sufficient material was available from both cell cultures originating from the ovary and testis to make excellent mitotic metaphase chromosomal preparations. We demonstrated the high efficiency of electroporation for genetic modification of the ovary-derived cell line. Thus, the established ovary-derived cell line could be efficiently used in cytogenetic and genomic studies. Abstract The last decade was marked by a steep rise in avian studies at genomic and cellular levels. Cell lines are important tools for in vitro studies in cell biology and cytogenetics. We developed a simple method of primary somatic cell culture establishment from the ovaries of the great tits (Parus major) and testes of ten Passerine species, characterized the cellular composition of the ovary-derived lines using RT-PCR and immunolocalization of the tissue-specific markers and tested the efficiency of two methods of genetic transformation of the ovary-derived cell line. We found that the ovary-derived cell cultures of the great tit were composed of fibroblasts mainly, but also contained interstitial and granulosa cells. They were cultivated until the 10th passage without any noticeable decrease in their proliferative activity. The testis-derived cell cultures had lower proliferative potential. However, both ovary- and testis-derived cell cultures provided enough material for high quality mitotic metaphase chromosome preparations. The efficiency of its transduction with lentivirus containing a GFP reporter was very low, while electroporation with episomal vectors expressing GFP resulted in a high yield of GFP-positive cells. The proposed method could be used for the generation of high quality material for various cytogenetic and genomic studies.
Collapse
|
21
|
Ng CS, Lai CK, Ke HM, Lee HH, Chen CF, Tang PC, Cheng HC, Lu MJ, Li WH, Tsai IJ. Genome assembly and evolutionary analysis of the mandarin duck Aix galericulata reveal strong genome conservation among ducks. Genome Biol Evol 2022; 14:6594746. [PMID: 35640266 PMCID: PMC9189614 DOI: 10.1093/gbe/evac083] [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] [Accepted: 05/25/2022] [Indexed: 11/13/2022] Open
Abstract
The mandarin duck, Aix galericulata, is popular in East Asian cultures and displays exaggerated sexual dimorphism, especially in feather traits during breeding seasons. We generated and annotated the first mandarin duck de novo assembly, which was 1.08 Gb in size and encoded 16,615 proteins. Using a phylogenomic approach calibrated with fossils and molecular divergences, we inferred that the last common ancestor of ducks occurred 13.3–26.7 Ma. The majority of the mandarin duck genome repetitive sequences belonged to the chicken repeat 1 (CR1) retroposon CR1-J2_Pass, which underwent a duck lineage-specific burst. Synteny analyses among ducks revealed infrequent chromosomal rearrangements in which breaks were enriched in LINE retrotransposons and DNA transposons. The calculation of the dN/dS ratio revealed that the majority of duck genes were under strong purifying selection. The expanded gene families in the mandarin duck are primarily involved in olfactory perception as well as the development and morphogenesis of feather and branching structures. This new reference genome will improve our understanding of the morphological and physiological characteristics of ducks and provide a valuable resource for functional genomics studies to investigate the feather traits of the mandarin duck.
Collapse
Affiliation(s)
- Chen Siang Ng
- Institute of Molecular and Cellular Biology, National Tsing Hua University, Hsinchu, Taiwan.,Department of Life Science, National Tsing Hua University, Hsinchu, Taiwan.,Bioresource Conservation Research Center, National Tsing Hua University, Hsinchu, Taiwan.,The iEGG and Animal Biotechnology Center, National Chung Hsing University, Taichung, Taiwan
| | - Cheng-Kuo Lai
- Biodiversity Research Center, Academia Sinica, Taipei, Taiwan.,Genome and Systems Biology Degree Program, National Taiwan University and Academia Sinica, Taipei, Taiwan
| | - Huei-Mien Ke
- Biodiversity Research Center, Academia Sinica, Taipei, Taiwan
| | - Hsin-Han Lee
- Biodiversity Research Center, Academia Sinica, Taipei, Taiwan
| | - Chih-Feng Chen
- The iEGG and Animal Biotechnology Center, National Chung Hsing University, Taichung, Taiwan.,Department of Animal Science, National Chung Hsing University, Taichung, Taiwan
| | - Pin-Chi Tang
- The iEGG and Animal Biotechnology Center, National Chung Hsing University, Taichung, Taiwan.,Department of Animal Science, National Chung Hsing University, Taichung, Taiwan
| | - Hsu-Chen Cheng
- The iEGG and Animal Biotechnology Center, National Chung Hsing University, Taichung, Taiwan.,Department of Life Science, National Chung Hsing University, Taichung, Taiwan
| | - Meiyeh J Lu
- Biodiversity Research Center, Academia Sinica, Taipei, Taiwan
| | - Wen-Hsiung Li
- The iEGG and Animal Biotechnology Center, National Chung Hsing University, Taichung, Taiwan.,Biodiversity Research Center, Academia Sinica, Taipei, Taiwan.,Department of Ecology and Evolution, University of Chicago, Chicago, USA
| | | |
Collapse
|
22
|
Ottenburghs J. Avian introgression patterns are consistent with Haldane's Rule. J Hered 2022; 113:363-370. [PMID: 35134952 PMCID: PMC9308041 DOI: 10.1093/jhered/esac005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Accepted: 01/27/2022] [Indexed: 11/13/2022] Open
Abstract
According to Haldane’s Rule, the heterogametic sex will show the greatest fitness reduction in a hybrid cross. In birds, where sex is determined by a ZW system, female hybrids are expected to experience lower fitness compared to male hybrids. This pattern has indeed been observed in several bird groups, but it is unknown whether the generality of Haldane’s Rule also extends to the molecular level. First, given the lower fitness of female hybrids, we can expect maternally inherited loci (i.e., mitochondrial and W-linked loci) to show lower introgression rates than biparentally inherited loci (i.e., autosomal loci) in females. Second, the faster evolution of Z-linked loci compared to autosomal loci and the hemizygosity of the Z-chromosome in females might speed up the accumulation of incompatible alleles on this sex chromosome, resulting in lower introgression rates for Z-linked loci than for autosomal loci. I tested these expectations by conducting a literature review which focused on studies that directly quantified introgression rates for autosomal, sex-linked, and mitochondrial loci. Although most studies reported introgression rates in line with Haldane’s Rule, it remains important to validate these genetic patterns with estimates of hybrid fitness and supporting field observations to rule out alternative explanations. Genomic data provide exciting opportunities to obtain a more fine-grained picture of introgression rates across the genome, which can consequently be linked to ecological and behavioral observations, potentially leading to novel insights into the genetic mechanisms underpinning Haldane’s Rule.
Collapse
Affiliation(s)
- Jente Ottenburghs
- Wildlife Ecology and Conservation, Wageningen University & Research, Wageningen, The Netherlands.,Forest Ecology and Forest Management, Wageningen University & Research, Wageningen, The Netherlands
| |
Collapse
|
23
|
Termignoni-Garcia F, Kirchman JJ, Clark J, Edwards SV. Comparative Population Genomics of Cryptic Speciation and Adaptive Divergence in Bicknell's and Gray-Cheeked Thrushes (Aves: Catharus bicknelli and Catharus minimus). Genome Biol Evol 2022; 14:evab255. [PMID: 34999784 PMCID: PMC8743040 DOI: 10.1093/gbe/evab255] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/10/2021] [Indexed: 02/07/2023] Open
Abstract
Cryptic speciation may occur when reproductive isolation is recent or the accumulation of morphological differences between sister lineages is slowed by stabilizing selection preventing phenotypic differentiation. In North America, Bicknell's Thrush (Catharus bicknelli) and its sister species, the Gray-cheeked Thrush (Catharus minimus), are parapatrically breeding migratory songbirds, distinguishable in nature only by subtle differences in song and coloration, and were recognized as distinct species only in the 1990s. Previous molecular studies have estimated that the species diverged approximately 120,000-420,000 YBP and found very low levels of introgression despite their similarity and sympatry in the spring (prebreeding) migration. To further clarify the history, genetic divergence, genomic structure, and adaptive processes in C. bicknelli and C. minimus, we sequenced and assembled high-coverage reference genomes of both species and resequenced genomes from population samples of C. bicknelli, C. minimus, and two individuals of the Swainson's Thrush (Catharus ustulatus). The genome of C. bicknelli exhibits markedly higher abundances of transposable elements compared with other Catharus and chicken. Demographic and admixture analyses confirm moderate genome-wide differentiation (Fst ≈ 0.10) and limited gene flow between C. bicknelli and C. minimus, but suggest a more recent divergence than estimates based on mtDNA. We find evidence of rapid evolution of the Z-chromosome and elevated divergence consistent with natural selection on genomic regions near genes involved with neuronal processes in C. bicknelli. These genomes are a useful resource for future investigations of speciation, migration, and adaptation in Catharus thrushes.
Collapse
Affiliation(s)
- Flavia Termignoni-Garcia
- Department of Organismic and Evolutionary Biology and Museum of Comparative Zoology, Harvard University, Cambridge, Massachusetts, USA
| | | | - Johnathan Clark
- Department of Organismic and Evolutionary Biology and Museum of Comparative Zoology, Harvard University, Cambridge, Massachusetts, USA
| | - Scott V Edwards
- Department of Organismic and Evolutionary Biology and Museum of Comparative Zoology, Harvard University, Cambridge, Massachusetts, USA
| |
Collapse
|
24
|
Sin SYW, Cloutier A, Nevitt G, Edwards SV. Olfactory receptor subgenome and expression in a highly olfactory procellariiform seabird. Genetics 2021; 220:6458329. [PMID: 34888634 DOI: 10.1093/genetics/iyab210] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2021] [Accepted: 10/04/2021] [Indexed: 11/13/2022] Open
Abstract
Procellariiform seabirds rely on their sense of smell for foraging and homing. Both genomes and transcriptomes yield important clues about how olfactory receptor (OR) subgenomes are shaped by natural and sexual selection, yet no transcriptomes have been made of any olfactory epithelium of any bird species thus far. Here we assembled a high-quality genome and nasal epithelium transcriptome of the Leach's storm-petrel (Oceanodroma leucorhoa) to extensively characterize their OR repertoire. Using a depth-of-coverage-assisted counting method, we estimated over 160 intact OR genes (∼500 including OR fragments). This method reveals the highest number of intact OR genes and the lowest proportion of pseudogenes compared to other waterbirds studied, and suggests that rates of OR gene duplication vary between major clades of birds, with particularly high rates in passerines. OR expression patterns reveal two OR genes (OR6-6 and OR5-11) highly expressed in adults, and four OR genes (OR14-14, OR14-12, OR10-2, and OR14-9) differentially expressed between age classes of storm-petrels. All four genes differentially expressed between age classes were more highly expressed in chicks compared to adults, suggesting that ORs genes may exhibit ontogenetic specializations. Three highly differentially expressed OR genes also had high copy number ratios, suggesting that expression variation may be linked to copy number in the genome. We provide better estimates of OR gene number by using a copy number-assisted counting method, and document ontogenetic changes in OR gene expression that may be linked to olfactory specialization. These results provide valuable insight into the expression, development, and macroevolution of olfaction in seabirds.
Collapse
Affiliation(s)
- Simon Yung Wa Sin
- Department of Organismic and Evolutionary Biology, Museum of Comparative Zoology, Harvard University, 26 Oxford Street, Cambridge, MA 02138, USA.,School of Biological Sciences, The University of Hong Kong, Pok Fu Lam Road, Hong Kong SAR, China
| | - Alison Cloutier
- Department of Organismic and Evolutionary Biology, Museum of Comparative Zoology, Harvard University, 26 Oxford Street, Cambridge, MA 02138, USA
| | - Gabrielle Nevitt
- Department of Neurobiology, Physiology and Behavior and the Graduate Group in Ecology, University of California, Davis, CA 95616, USA
| | - Scott V Edwards
- Department of Organismic and Evolutionary Biology, Museum of Comparative Zoology, Harvard University, 26 Oxford Street, Cambridge, MA 02138, USA
| |
Collapse
|
25
|
Abstract
Natural history collections are invaluable repositories of biological information that provide an unrivaled record of Earth's biodiversity. Museum genomics-genomics research using traditional museum and cryogenic collections and the infrastructure supporting these investigations-has particularly enhanced research in ecology and evolutionary biology, the study of extinct organisms, and the impact of anthropogenic activity on biodiversity. However, leveraging genomics in biological collections has exposed challenges, such as digitizing, integrating, and sharing collections data; updating practices to ensure broadly optimal data extraction from existing and new collections; and modernizing collections practices, infrastructure, and policies to ensure fair, sustainable, and genomically manifold uses of museum collections by increasingly diverse stakeholders. Museum genomics collections are poised to address these challenges and, with increasingly sensitive genomics approaches, will catalyze a future era of reproducibility, innovation, and insight made possible through integrating museum and genome sciences.
Collapse
Affiliation(s)
- Daren C Card
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, Massachusetts 02138, USA; .,Museum of Comparative Zoology, Harvard University, Cambridge, Massachusetts 02138, USA
| | - Beth Shapiro
- Department of Ecology and Evolutionary Biology, University of California, Santa Cruz, California 95064, USA.,Howard Hughes Medical Institute, University of California, Santa Cruz, California 95064, USA
| | - Gonzalo Giribet
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, Massachusetts 02138, USA; .,Museum of Comparative Zoology, Harvard University, Cambridge, Massachusetts 02138, USA
| | - Craig Moritz
- Centre for Biodiversity Analysis and Research School of Biology, The Australian National University, Canberra, Australian Capital Territory 0200, Australia
| | - Scott V Edwards
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, Massachusetts 02138, USA; .,Museum of Comparative Zoology, Harvard University, Cambridge, Massachusetts 02138, USA
| |
Collapse
|
26
|
Chen D, Hosner PA, Dittmann DL, O'Neill JP, Birks SM, Braun EL, Kimball RT. Divergence time estimation of Galliformes based on the best gene shopping scheme of ultraconserved elements. BMC Ecol Evol 2021; 21:209. [PMID: 34809586 PMCID: PMC8609756 DOI: 10.1186/s12862-021-01935-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Accepted: 11/08/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Divergence time estimation is fundamental to understanding many aspects of the evolution of organisms, such as character evolution, diversification, and biogeography. With the development of sequence technology, improved analytical methods, and knowledge of fossils for calibration, it is possible to obtain robust molecular dating results. However, while phylogenomic datasets show great promise in phylogenetic estimation, the best ways to leverage the large amounts of data for divergence time estimation has not been well explored. A potential solution is to focus on a subset of data for divergence time estimation, which can significantly reduce the computational burdens and avoid problems with data heterogeneity that may bias results. RESULTS In this study, we obtained thousands of ultraconserved elements (UCEs) from 130 extant galliform taxa, including representatives of all genera, to determine the divergence times throughout galliform history. We tested the effects of different "gene shopping" schemes on divergence time estimation using a carefully, and previously validated, set of fossils. Our results found commonly used clock-like schemes may not be suitable for UCE dating (or other data types) where some loci have little information. We suggest use of partitioning (e.g., PartitionFinder) and selection of tree-like partitions may be good strategies to select a subset of data for divergence time estimation from UCEs. Our galliform time tree is largely consistent with other molecular clock studies of mitochondrial and nuclear loci. With our increased taxon sampling, a well-resolved topology, carefully vetted fossil calibrations, and suitable molecular dating methods, we obtained a high quality galliform time tree. CONCLUSIONS We provide a robust galliform backbone time tree that can be combined with more fossil records to further facilitate our understanding of the evolution of Galliformes and can be used as a resource for comparative and biogeographic studies in this group.
Collapse
Affiliation(s)
- De Chen
- MOE Key Laboratory for Biodiversity Science and Ecological Engineering, College of Life Sciences, Beijing Normal University, Beijing, China
- Department of Biology, University of Florida, Gainesville, FL, USA
| | - Peter A Hosner
- Department of Biology, University of Florida, Gainesville, FL, USA
- Natural History Museum of Denmark and Center for Global Mountain Biodiversity, University of Copenhagen, Copenhagen, Denmark
| | - Donna L Dittmann
- Museum of Natural Science, Louisiana State University, Baton Rouge, LA, USA
| | - John P O'Neill
- Museum of Natural Science, Louisiana State University, Baton Rouge, LA, USA
| | - Sharon M Birks
- Burke Museum of Natural History and Culture, University of Washington, Seattle, WA, USA
| | - Edward L Braun
- Department of Biology, University of Florida, Gainesville, FL, USA
| | | |
Collapse
|
27
|
Protein Structure, Models of Sequence Evolution, and Data Type Effects in Phylogenetic Analyses of Mitochondrial Data: A Case Study in Birds. DIVERSITY 2021. [DOI: 10.3390/d13110555] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Phylogenomic analyses have revolutionized the study of biodiversity, but they have revealed that estimated tree topologies can depend, at least in part, on the subset of the genome that is analyzed. For example, estimates of trees for avian orders differ if protein-coding or non-coding data are analyzed. The bird tree is a good study system because the historical signal for relationships among orders is very weak, which should permit subtle non-historical signals to be identified, while monophyly of orders is strongly corroborated, allowing identification of strong non-historical signals. Hydrophobic amino acids in mitochondrially-encoded proteins, which are expected to be found in transmembrane helices, have been hypothesized to be associated with non-historical signals. We tested this hypothesis by comparing the evolution of transmembrane helices and extramembrane segments of mitochondrial proteins from 420 bird species, sampled from most avian orders. We estimated amino acid exchangeabilities for both structural environments and assessed the performance of phylogenetic analysis using each data type. We compared those relative exchangeabilities with values calculated using a substitution matrix for transmembrane helices estimated using a variety of nuclear- and mitochondrially-encoded proteins, allowing us to compare the bird-specific mitochondrial models with a general model of transmembrane protein evolution. To complement our amino acid analyses, we examined the impact of protein structure on patterns of nucleotide evolution. Models of transmembrane and extramembrane sequence evolution for amino acids and nucleotides exhibited striking differences, but there was no evidence for strong topological data type effects. However, incorporating protein structure into analyses of mitochondrially-encoded proteins improved model fit. Thus, we believe that considering protein structure will improve analyses of mitogenomic data, both in birds and in other taxa.
Collapse
|