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Gable SM, Bushroe N, Mendez J, Wilson A, Pinto B, Gamble T, Tollis M. Differential Conservation and Loss of CR1 Retrotransposons in Squamates Reveals Lineage-Specific Genome Dynamics across Reptiles. bioRxiv 2024:2024.02.09.579686. [PMID: 38405926 PMCID: PMC10888918 DOI: 10.1101/2024.02.09.579686] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/27/2024]
Abstract
Transposable elements (TEs) are repetitive DNA sequences which create mutations and generate genetic diversity across the tree of life. In amniotic vertebrates, TEs have been mainly studied in mammals and birds, whose genomes generally display low TE diversity. Squamates (Order Squamata; ~11,000 extant species of lizards and snakes) show as much variation in TE abundance and activity as they do in species and phenotypes. Despite this high TE activity, squamate genomes are remarkably uniform in size. We hypothesize that novel, lineage-specific dynamics have evolved over the course of squamate evolution to constrain genome size across the order. Thus, squamates may represent a prime model for investigations into TE diversity and evolution. To understand the interplay between TEs and host genomes, we analyzed the evolutionary history of the CR1 retrotransposon, a TE family found in most tetrapod genomes. We compared 113 squamate genomes to the genomes of turtles, crocodilians, and birds, and used ancestral state reconstruction to identify shifts in the rate of CR1 copy number evolution across reptiles. We analyzed the repeat landscapes of CR1 in squamate genomes and determined that shifts in the rate of CR1 copy number evolution are associated with lineage-specific variation in CR1 activity. We then used phylogenetic reconstruction of CR1 subfamilies across amniotes to reveal both recent and ancient CR1 subclades across the squamate tree of life. The patterns of CR1 evolution in squamates contrast other amniotes, suggesting key differences in how TEs interact with different host genomes and at different points across evolutionary history.
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Affiliation(s)
- Simone M Gable
- School of Informatics, Computing, and Cyber Systems, Northern Arizona University, Flagstaff, AZ, USA
| | - Nicholas Bushroe
- School of Informatics, Computing, and Cyber Systems, Northern Arizona University, Flagstaff, AZ, USA
| | - Jasmine Mendez
- School of Informatics, Computing, and Cyber Systems, Northern Arizona University, Flagstaff, AZ, USA
| | - Adam Wilson
- School of Informatics, Computing, and Cyber Systems, Northern Arizona University, Flagstaff, AZ, USA
| | - Brendan Pinto
- 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
| | - Marc Tollis
- School of Informatics, Computing, and Cyber Systems, Northern Arizona University, Flagstaff, AZ, USA
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Abstract
Transposable elements exhibit a base composition that is often different from the genomic average and from hosts’ genes. The most common compositional bias is towards Adenosine and Thymine, although this bias is not universal, and elements with drastically different base composition can coexist within the same genome. The AT-richness of transposable elements is apparently maladaptive because it results in poor transcription and sub-optimal translation of proteins encoded by the elements. The cause(s) of this unusual base composition remain unclear and have yet to be investigated. Here, I review what is known about the nucleotide content of transposable elements and how this content can affect the genome of their host as well as their own replication. The compositional bias of transposable elements could result from several non-exclusive processes including horizontal transfer, mutational bias, and selection. It appears that mutation alone cannot explain the high AT-content of transposons and that selection plays a major role in the evolution of the compositional bias. The reason why selection would favor a maladaptive nucleotide content remains however unexplained and is an area of investigation that clearly deserves attention.
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Du Z, D’Alessandro E, Zheng Y, Wang M, Chen C, Wang X, Song C. Retrotransposon Insertion Polymorphisms (RIPs) in Pig Coat Color Candidate Genes. Animals (Basel) 2022; 12:ani12080969. [PMID: 35454216 PMCID: PMC9031378 DOI: 10.3390/ani12080969] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Revised: 03/28/2022] [Accepted: 04/05/2022] [Indexed: 12/17/2022] Open
Abstract
The diversity of livestock coat color results from human positive selection and represents an indispensable part of breed identity. As an important biodiversity resource, pigs have many special characteristics, including the most visualized feature, coat color, and excellent adaptation, and the coat color represents an important phenotypic characteristic of the pig breed. Exploring the genetic mechanisms of phenotypic characteristics and the melanocortin system is of considerable interest in domestic animals because their energy metabolism and pigmentation have been under strong selection. In this study, 20 genes related to coat color in mammals were selected, and the structural variations (SVs) in these genic regions were identified by sequence alignment across 17 assembled pig genomes, from representing different types of pigs (miniature, lean, and fat type). A total of 167 large structural variations (>50 bp) of coat-color genes, which overlap with retrotransposon insertions (>50 bp), were obtained and designated as putative RIPs. Finally, 42 RIPs were confirmed by PCR detection. Additionally, eleven RIP sites were further evaluated for their genotypic distributions by PCR in more individuals of eleven domesticated breeds representing different coat color groups. Differential distributions of these RIPs were observed across populations, and some RIPs may be associated with breed differences.
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Affiliation(s)
- Zhanyu Du
- College of Animal Science and Technology, Yangzhou University, Yangzhou 225009, China; (Z.D.); (Y.Z.); (M.W.); (C.C.); (X.W.)
| | - Enrico D’Alessandro
- Department of Veterinary Sciences, University of Messina, Via Palatucci, 98168 Messina, Italy;
| | - Yao Zheng
- College of Animal Science and Technology, Yangzhou University, Yangzhou 225009, China; (Z.D.); (Y.Z.); (M.W.); (C.C.); (X.W.)
| | - Mengli Wang
- College of Animal Science and Technology, Yangzhou University, Yangzhou 225009, China; (Z.D.); (Y.Z.); (M.W.); (C.C.); (X.W.)
| | - Cai Chen
- College of Animal Science and Technology, Yangzhou University, Yangzhou 225009, China; (Z.D.); (Y.Z.); (M.W.); (C.C.); (X.W.)
| | - Xiaoyan Wang
- College of Animal Science and Technology, Yangzhou University, Yangzhou 225009, China; (Z.D.); (Y.Z.); (M.W.); (C.C.); (X.W.)
| | - Chengyi Song
- College of Animal Science and Technology, Yangzhou University, Yangzhou 225009, China; (Z.D.); (Y.Z.); (M.W.); (C.C.); (X.W.)
- Correspondence:
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Tusso S, Suo F, Liang Y, Du LL, Wolf JBW. Reactivation of transposable elements following hybridization in fission yeast. Genome Res 2021; 32:324-336. [PMID: 34907076 PMCID: PMC8805722 DOI: 10.1101/gr.276056.121] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Accepted: 12/09/2021] [Indexed: 11/29/2022]
Abstract
Hybridization is thought to reactivate transposable elements (TEs) that were efficiently suppressed in the genomes of the parental hosts. Here, we provide evidence for this “genomic shock hypothesis” in the fission yeast Schizosaccharomyces pombe. In this species, two divergent lineages (Sp and Sk) have experienced recent, likely human-induced, hybridization. We used long-read sequencing data to assemble genomes of 37 samples derived from 31 S. pombe strains spanning a wide range of ancestral admixture proportions. A comprehensive TE inventory revealed exclusive presence of long terminal repeat (LTR) retrotransposons. Sequence analysis of active full-length elements, as well as solo LTRs, revealed a complex history of homologous recombination. Population genetic analyses of syntenic sequences placed insertion of many solo LTRs before the split of the Sp and Sk lineages. Most full-length elements were inserted more recently, after hybridization. With the exception of a single full-length element with signs of positive selection, both solo LTRs and, in particular, full-length elements carry signatures of purifying selection indicating effective removal by the host. Consistent with reactivation upon hybridization, the number of full-length LTR retrotransposons, varying extensively from zero to 87 among strains, significantly increases with the degree of genomic admixture. This study gives a detailed account of global TE diversity in S. pombe, documents complex recombination histories within TE elements, and provides evidence for the “genomic shock hypothesis.”
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Affiliation(s)
| | - Fang Suo
- National Institute of Biological Sciences
| | - Yue Liang
- National Institute of Biological Sciences
| | - Li-Lin Du
- National Institute of Biological Sciences
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Petersen M, Winter S, Coimbra R, J de Jong M, Kapitonov VV, Nilsson MA. Population analysis of retrotransposons in giraffe genomes supports RTE decline and widespread LINE1 activity in Giraffidae. Mob DNA 2021; 12:27. [PMID: 34836553 PMCID: PMC8620236 DOI: 10.1186/s13100-021-00254-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Accepted: 10/25/2021] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND The majority of structural variation in genomes is caused by insertions of transposable elements (TEs). In mammalian genomes, the main TE fraction is made up of autonomous and non-autonomous non-LTR retrotransposons commonly known as LINEs and SINEs (Long and Short Interspersed Nuclear Elements). Here we present one of the first population-level analysis of TE insertions in a non-model organism, the giraffe. Giraffes are ruminant artiodactyls, one of the few mammalian groups with genomes that are colonized by putatively active LINEs of two different clades of non-LTR retrotransposons, namely the LINE1 and RTE/BovB LINEs as well as their associated SINEs. We analyzed TE insertions of both types, and their associated SINEs in three giraffe genome assemblies, as well as across a population level sampling of 48 individuals covering all extant giraffe species. RESULTS The comparative genome screen identified 139,525 recent LINE1 and RTE insertions in the sampled giraffe population. The analysis revealed a drastically reduced RTE activity in giraffes, whereas LINE1 is still actively propagating in the genomes of extant (sub)-species. In concert with the extremely low activity of the giraffe RTE, we also found that RTE-dependent SINEs, namely Bov-tA and Bov-A2, have been virtually immobile in the last 2 million years. Despite the high current activity of the giraffe LINE1, we did not find evidence for the presence of currently active LINE1-dependent SINEs. TE insertion heterozygosity rates differ among the different (sub)-species, likely due to divergent population histories. CONCLUSIONS The horizontally transferred RTE/BovB and its derived SINEs appear to be close to inactivation and subsequent extinction in the genomes of extant giraffe species. This is the first time that the decline of a TE family has been meticulously analyzed from a population genetics perspective. Our study shows how detailed information about past and present TE activity can be obtained by analyzing large-scale population-level genomic data sets.
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Affiliation(s)
- Malte Petersen
- Max Planck Institute of Immunobiology and Epigenetics, Stübeweg 51, 79108, Freiburg, Germany
| | - Sven Winter
- Senckenberg Biodiversity and Climate Research Centre, Senckenberganlage 25, 60325, Frankfurt am Main, Germany
| | - Raphael Coimbra
- Senckenberg Biodiversity and Climate Research Centre, Senckenberganlage 25, 60325, Frankfurt am Main, Germany
- Institute for Ecology, Evolution and Diversity, Goethe University, Max-von-Laue-Straße 13, 60438, Frankfurt am Main, Germany
| | - Menno J de Jong
- Senckenberg Biodiversity and Climate Research Centre, Senckenberganlage 25, 60325, Frankfurt am Main, Germany
| | - Vladimir V Kapitonov
- Senckenberg Biodiversity and Climate Research Centre, Senckenberganlage 25, 60325, Frankfurt am Main, Germany
- LOEWE Centre for Translational Biodiversity Genomics (LOEWE-TBG), Senckenberganlage 25, 60325, Frankfurt am Main, Germany
| | - Maria A Nilsson
- Senckenberg Biodiversity and Climate Research Centre, Senckenberganlage 25, 60325, Frankfurt am Main, Germany.
- LOEWE Centre for Translational Biodiversity Genomics (LOEWE-TBG), Senckenberganlage 25, 60325, Frankfurt am Main, Germany.
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Patil AB, Vijay N. Repetitive genomic regions and the inference of demographic history. Heredity (Edinb) 2021; 127:151-166. [PMID: 34002046 PMCID: PMC8322061 DOI: 10.1038/s41437-021-00443-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2021] [Revised: 04/16/2021] [Accepted: 04/17/2021] [Indexed: 02/03/2023] Open
Abstract
Inference of demographic histories using whole-genome datasets has provided insights into diversification, adaptation, hybridization, and plant-pathogen interactions, and stimulated debate on the impact of anthropogenic interventions and past climate on species demography. However, the impact of repetitive genomic regions on these inferences has mostly been ignored by masking of repeats. We use the Populus trichocarpa genome (Pop_tri_v3) to show that masking of repeat regions leads to lower estimates of effective population size (Ne) in the distant past in contrast to an increase in Ne estimates in recent times. However, in human datasets, masking of repeats resulted in lower estimates of Ne at all time points. We demonstrate that repeats affect demographic inferences using diverse methods like PSMC, MSMC, SMC++, and the Stairway plot. Our genomic analysis revealed that the biases in Ne estimates were dependent on the repeat class type and its abundance in each atomic interval. Notably, we observed a weak, yet consistently significant negative correlation between the repeat abundance of an atomic interval and the Ne estimates for that interval, which potentially reflects the recombination rate variation within the genome. The rationale for the masking of repeats has been that variants identified within these regions are erroneous. We find that polymorphisms in some repeat classes occur in callable regions and reflect reliable coalescence histories (e.g., LTR Gypsy, LTR Copia). The current demography inference methods do not handle repeats explicitly, and hence the effect of individual repeat classes needs careful consideration in comparative analysis. Deciphering the repeat demographic histories might provide a clear understanding of the processes involved in repeat accumulation.
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Affiliation(s)
- Ajinkya Bharatraj Patil
- Computational Evolutionary Genomics Lab, Department of Biological Sciences, IISER Bhopal, Bhauri, Madhya Pradesh, India
| | - Nagarjun Vijay
- Computational Evolutionary Genomics Lab, Department of Biological Sciences, IISER Bhopal, Bhauri, Madhya Pradesh, India.
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Almojil D, Bourgeois Y, Falis M, Hariyani I, Wilcox J, Boissinot S. The Structural, Functional and Evolutionary Impact of Transposable Elements in Eukaryotes. Genes (Basel) 2021; 12:genes12060918. [PMID: 34203645 PMCID: PMC8232201 DOI: 10.3390/genes12060918] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2021] [Revised: 06/04/2021] [Accepted: 06/07/2021] [Indexed: 12/22/2022] Open
Abstract
Transposable elements (TEs) are nearly ubiquitous in eukaryotes. The increase in genomic data, as well as progress in genome annotation and molecular biology techniques, have revealed the vast number of ways mobile elements have impacted the evolution of eukaryotes. In addition to being the main cause of difference in haploid genome size, TEs have affected the overall organization of genomes by accumulating preferentially in some genomic regions, by causing structural rearrangements or by modifying the recombination rate. Although the vast majority of insertions is neutral or deleterious, TEs have been an important source of evolutionary novelties and have played a determinant role in the evolution of fundamental biological processes. TEs have been recruited in the regulation of host genes and are implicated in the evolution of regulatory networks. They have also served as a source of protein-coding sequences or even entire genes. The impact of TEs on eukaryotic evolution is only now being fully appreciated and the role they may play in a number of biological processes, such as speciation and adaptation, remains to be deciphered.
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Affiliation(s)
- Dareen Almojil
- New York University Abu Dhabi, Saadiyat Island, Abu Dhabi P.O. Box 129188, United Arab Emirates; (D.A.); (M.F.); (I.H.); (J.W.)
| | - Yann Bourgeois
- School of Biological Sciences, University of Portsmouth, Portsmouth, UK;
| | - Marcin Falis
- New York University Abu Dhabi, Saadiyat Island, Abu Dhabi P.O. Box 129188, United Arab Emirates; (D.A.); (M.F.); (I.H.); (J.W.)
| | - Imtiyaz Hariyani
- New York University Abu Dhabi, Saadiyat Island, Abu Dhabi P.O. Box 129188, United Arab Emirates; (D.A.); (M.F.); (I.H.); (J.W.)
| | - Justin Wilcox
- New York University Abu Dhabi, Saadiyat Island, Abu Dhabi P.O. Box 129188, United Arab Emirates; (D.A.); (M.F.); (I.H.); (J.W.)
- Center for Genomics and Systems Biology, New York University Abu Dhabi, Saadiyat Island, Abu Dhabi P.O. Box 129188, United Arab Emirates
| | - Stéphane Boissinot
- New York University Abu Dhabi, Saadiyat Island, Abu Dhabi P.O. Box 129188, United Arab Emirates; (D.A.); (M.F.); (I.H.); (J.W.)
- Center for Genomics and Systems Biology, New York University Abu Dhabi, Saadiyat Island, Abu Dhabi P.O. Box 129188, United Arab Emirates
- Correspondence:
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Bourgeois Y, Ruggiero RP, Hariyani I, Boissinot S. Disentangling the determinants of transposable elements dynamics in vertebrate genomes using empirical evidences and simulations. PLoS Genet 2020; 16:e1009082. [PMID: 33017388 PMCID: PMC7561263 DOI: 10.1371/journal.pgen.1009082] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Revised: 10/15/2020] [Accepted: 08/25/2020] [Indexed: 12/14/2022] Open
Abstract
The interactions between transposable elements (TEs) and their hosts constitute one of the most profound co-evolutionary processes found in nature. The population dynamics of TEs depends on factors specific to each TE families, such as the rate of transposition and insertional preference, the demographic history of the host and the genomic landscape. How these factors interact has yet to be investigated holistically. Here we are addressing this question in the green anole (Anolis carolinensis) whose genome contains an extraordinary diversity of TEs (including non-LTR retrotransposons, SINEs, LTR-retrotransposons and DNA transposons). We observed a positive correlation between recombination rate and frequency of TEs and densities for LINEs, SINEs and DNA transposons. For these elements, there was a clear impact of demography on TE frequency and abundance, with a loss of polymorphic elements and skewed frequency spectra in recently expanded populations. On the other hand, some LTR-retrotransposons displayed patterns consistent with a very recent phase of intense amplification. To determine how demography, genomic features and intrinsic properties of TEs interact we ran simulations using SLiM3. We determined that i) short TE insertions are not strongly counter-selected, but long ones are, ii) neutral demographic processes, linked selection and preferential insertion may explain positive correlations between average TE frequency and recombination, iii) TE insertions are unlikely to have been massively recruited in recent adaptation. We demonstrate that deterministic and stochastic processes have different effects on categories of TEs and that a combination of empirical analyses and simulations can disentangle these mechanisms.
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Affiliation(s)
- Yann Bourgeois
- School of Biological Sciences, University of Portsmouth, Portsmouth, United Kingdom
- New York University Abu Dhabi, Saadiyat Island Campus, Abu Dhabi, United Arab Emirates
- * E-mail: (YB); (SB)
| | - Robert P. Ruggiero
- New York University Abu Dhabi, Saadiyat Island Campus, Abu Dhabi, United Arab Emirates
- Department of Biology, Southeast Missouri State University, Cape Girardeau, MO, United States of America
| | - Imtiyaz Hariyani
- New York University Abu Dhabi, Saadiyat Island Campus, Abu Dhabi, United Arab Emirates
| | - Stéphane Boissinot
- New York University Abu Dhabi, Saadiyat Island Campus, Abu Dhabi, United Arab Emirates
- * E-mail: (YB); (SB)
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Bourgeois Y, Boissinot S. Selection at behavioural, developmental and metabolic genes is associated with the northward expansion of a successful tropical colonizer. Mol Ecol 2019; 28:3523-3543. [PMID: 31233650 DOI: 10.1111/mec.15162] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Accepted: 05/28/2019] [Indexed: 02/06/2023]
Abstract
What makes a species able to colonize novel environments? This question is key to understand the dynamics of adaptive radiations and ecological niche shifts, but the mechanisms that underlie expansion into novel habitats remain poorly understood at a genomic scale. Lizards from the genus Anolis are typically tropical, and the green anole (Anolis carolinensis) constitutes an exception since it expanded into temperate North America from subtropical Florida. Thus, we used the green anole as a model to investigate signatures of selection associated with colonization of a new environment, namely temperate North America. To this end, we analysed 29 whole-genome sequences, covering the entire native range of the species. We used a combination of recent methods to quantify both positive and balancing selection in northern populations, including FST outlier methods, machine learning and ancestral recombination graphs. We naively scanned for genes of interest and assessed the overlap between multiple tests. Strikingly, we identified many genes involved in behaviour, suggesting that the recent successful colonization of northern environments may have been linked to behavioural shifts as well as physiological adaptation. Using a candidate genes strategy, we determined that genes involved in response to cold or behaviour displayed more frequently signals of selection, while controlling for local recombination rate, gene clustering and gene length. In addition, we found signatures of balancing selection at immune genes in all investigated genetic groups, but also at genes involved in neuronal and anatomical development.
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Affiliation(s)
- Yann Bourgeois
- New York University Abu Dhabi, Abu Dhabi, United Arab Emirates
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10
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Bourgeois Y, Ruggiero RP, Manthey JD, Boissinot S. Recent Secondary Contacts, Linked Selection, and Variable Recombination Rates Shape Genomic Diversity in the Model Species Anolis carolinensis. Genome Biol Evol 2019; 11:2009-2022. [PMID: 31134281 PMCID: PMC6681179 DOI: 10.1093/gbe/evz110] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/23/2019] [Indexed: 12/14/2022] Open
Abstract
Gaining a better understanding on how selection and neutral processes affect genomic diversity is essential to gain better insights into the mechanisms driving adaptation and speciation. However, the evolutionary processes affecting variation at a genomic scale have not been investigated in most vertebrate lineages. Here, we present the first population genomics survey using whole genome resequencing in the green anole (Anolis carolinensis). Anoles have been intensively studied to understand mechanisms underlying adaptation and speciation. The green anole in particular is an important model to study genome evolution. We quantified how demography, recombination, and selection have led to the current genetic diversity of the green anole by using whole-genome resequencing of five genetic clusters covering the entire species range. The differentiation of green anole's populations is consistent with a northward expansion from South Florida followed by genetic isolation and subsequent gene flow among adjacent genetic clusters. Dispersal out-of-Florida was accompanied by a drastic population bottleneck followed by a rapid population expansion. This event was accompanied by male-biased dispersal and/or selective sweeps on the X chromosome. We show that the interaction between linked selection and recombination is the main contributor to the genomic landscape of differentiation in the anole genome.
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Affiliation(s)
| | | | - Joseph D Manthey
- New York University Abu Dhabi, United Arab Emirates
- Department of Biological Sciences, Texas Tech University
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11
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Bourgeois Y, Boissinot S. On the Population Dynamics of Junk: A Review on the Population Genomics of Transposable Elements. Genes (Basel) 2019; 10:genes10060419. [PMID: 31151307 PMCID: PMC6627506 DOI: 10.3390/genes10060419] [Citation(s) in RCA: 64] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2019] [Revised: 05/05/2019] [Accepted: 05/21/2019] [Indexed: 01/18/2023] Open
Abstract
Transposable elements (TEs) play an important role in shaping genomic organization and structure, and may cause dramatic changes in phenotypes. Despite the genetic load they may impose on their host and their importance in microevolutionary processes such as adaptation and speciation, the number of population genetics studies focused on TEs has been rather limited so far compared to single nucleotide polymorphisms (SNPs). Here, we review the current knowledge about the dynamics of transposable elements at recent evolutionary time scales, and discuss the mechanisms that condition their abundance and frequency. We first discuss non-adaptive mechanisms such as purifying selection and the variable rates of transposition and elimination, and then focus on positive and balancing selection, to finally conclude on the potential role of TEs in causing genomic incompatibilities and eventually speciation. We also suggest possible ways to better model TEs dynamics in a population genomics context by incorporating recent advances in TEs into the rich information provided by SNPs about the demography, selection, and intrinsic properties of genomes.
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Affiliation(s)
- Yann Bourgeois
- New York University Abu Dhabi, P.O. 129188, Saadiyat Island, Abu Dhabi, United Arab Emirates.
| | - Stéphane Boissinot
- New York University Abu Dhabi, P.O. 129188, Saadiyat Island, Abu Dhabi, United Arab Emirates.
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12
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Abstract
Among the multitude of papers published yearly in scientific journals, precious few publications may be worth looking back in half a century to appreciate the significance of the discoveries that would later become common knowledge and get a chance to shape a field or several adjacent fields. Here, Kimura's fundamental concept of neutral mutation-random drift, which was published 50 years ago, is re-examined in light of its pervasive influence on comparative genomics and, more specifically, on the contribution of transposable elements to eukaryotic genome evolution.
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Affiliation(s)
- Irina R Arkhipova
- Josephine Bay Paul Center for Comparative Molecular Biology and Evolution, Marine Biological Laboratory, Woods Hole, MA
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13
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Lammers F, Blumer M, Rücklé C, Nilsson MA. Retrophylogenomics in rorquals indicate large ancestral population sizes and a rapid radiation. Mob DNA 2019; 10:5. [PMID: 30679961 PMCID: PMC6340175 DOI: 10.1186/s13100-018-0143-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Accepted: 12/18/2018] [Indexed: 02/03/2023] Open
Abstract
Background Baleen whales (Mysticeti) are the largest animals on earth and their evolutionary history has been studied in detail, but some relationships still remain contentious. In particular, reconstructing the phylogenetic position of the gray whales (Eschrichtiidae) has been complicated by evolutionary processes such as gene flow and incomplete lineage sorting (ILS). Here, whole-genome sequencing data of the extant baleen whale radiation allowed us to identify transposable element (TE) insertions in order to perform phylogenomic analyses and measure germline insertion rates of TEs. Baleen whales exhibit the slowest nucleotide substitution rate among mammals, hence we additionally examined the evolutionary insertion rates of TE insertions across the genomes. Results In eleven whole-genome sequences representing the extant radiation of baleen whales, we identified 91,859 CHR-SINE insertions that were used to reconstruct the phylogeny with different approaches as well as perform evolutionary network analyses and a quantification of conflicting phylogenetic signals. Our results indicate that the radiation of rorquals and gray whales might not be bifurcating. The morphologically derived gray whales are placed inside the rorqual group, as the sister-species to humpback and fin whales. Detailed investigation of TE insertion rates confirm that a mutational slow down in the whale lineage is present but less pronounced for TEs than for nucleotide substitutions. Conclusions Whole genome sequencing based detection of TE insertions showed that the speciation processes in baleen whales represent a rapid radiation. Large genome-scale TE data sets in addition allow to understand retrotransposition rates in non-model organisms and show the potential for TE calling methods to study the evolutionary history of species. Electronic supplementary material The online version of this article (10.1186/s13100-018-0143-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Fritjof Lammers
- 1Senckenberg Biodiversity and Climate Research Centre, Senckenberg Gesellschaft für Naturforschung, Senckenberganlage 25, 60325 Frankfurt am Main, Germany.,LOEWE Centre for Translational Biodiversity Genomics (LOEWE-TBG), Senckenberganlage 25, 60325 Frankfurt am Main, Germany.,3Institute for Ecology, Evolution and Diversity, Goethe University Frankfurt, Biologicum, Max-von-Laue-Straße 13, 60439 Frankfurt am Main, Germany
| | - Moritz Blumer
- 1Senckenberg Biodiversity and Climate Research Centre, Senckenberg Gesellschaft für Naturforschung, Senckenberganlage 25, 60325 Frankfurt am Main, Germany
| | - Cornelia Rücklé
- 1Senckenberg Biodiversity and Climate Research Centre, Senckenberg Gesellschaft für Naturforschung, Senckenberganlage 25, 60325 Frankfurt am Main, Germany
| | - Maria A Nilsson
- 1Senckenberg Biodiversity and Climate Research Centre, Senckenberg Gesellschaft für Naturforschung, Senckenberganlage 25, 60325 Frankfurt am Main, Germany.,LOEWE Centre for Translational Biodiversity Genomics (LOEWE-TBG), Senckenberganlage 25, 60325 Frankfurt am Main, Germany
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14
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Manthey JD, Moyle RG, Boissinot S. Multiple and Independent Phases of Transposable Element Amplification in the Genomes of Piciformes (Woodpeckers and Allies). Genome Biol Evol 2018; 10:1445-1456. [PMID: 29850797 PMCID: PMC6007501 DOI: 10.1093/gbe/evy105] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/22/2018] [Indexed: 12/15/2022] Open
Abstract
The small and conserved genomes of birds are likely a result of flight-related metabolic constraints. Recombination-driven deletions and minimal transposable element (TE) expansions have led to continually shrinking genomes during evolution of many lineages of volant birds. Despite constraints of genome size in birds, we identified multiple waves of amplification of TEs in Piciformes (woodpeckers, honeyguides, toucans, and barbets). Relative to other bird species’ genomic TE abundance (< 10% of genome), we found ∼17–30% TE content in multiple clades within Piciformes. Several families of the retrotransposon superfamily chicken repeat 1 (CR1) expanded in at least three different waves of activity. The most recent CR1 expansions (∼4–7% of genome) preceded bursts of diversification in the woodpecker clade and in the American barbets + toucans clade. Additionally, we identified several thousand polymorphic CR1 insertions (hundreds per individual) in three closely related woodpecker species. Woodpecker CR1 insertion polymorphisms are maintained at lower frequencies than single nucleotide polymorphisms indicating that purifying selection is acting against additional CR1 copies and that these elements impose a fitness cost on their host. These findings provide evidence of large scale and ongoing TE activity in avian genomes despite continual constraint on genome size.
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Affiliation(s)
- Joseph D Manthey
- New York University Abu Dhabi, UAE.,Department of Biological Sciences, Texas Tech University
| | - Robert G Moyle
- Department of Ecology and Evolutionary Biology, Biodiversity Institute, University of Kansas
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15
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Stritt C, Gordon SP, Wicker T, Vogel JP, Roulin AC. Recent Activity in Expanding Populations and Purifying Selection Have Shaped Transposable Element Landscapes across Natural Accessions of the Mediterranean Grass Brachypodium distachyon. Genome Biol Evol 2018; 10:304-318. [PMID: 29281015 PMCID: PMC5786231 DOI: 10.1093/gbe/evx276] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/20/2017] [Indexed: 01/05/2023] Open
Abstract
Transposable element (TE) activity has emerged as a major cause of variation in genome size and structure among species. To what extent TEs contribute to genetic variation and divergence within species, however, is much less clear, mainly because population genomic data have so far only been available for the classical model organisms. In this study, we use the annual Mediterranean grass Brachypodium distachyon to investigate TE dynamics in natural populations. Using whole-genome sequencing data for 53 natural accessions, we identified more than 5,400 TE polymorphisms across the studied genomes. We found, first, that while population bottlenecks and expansions have shaped genetic diversity in B. distachyon, these events did not lead to lineage-specific activations of TE families, as observed in other species. Instead, the same families have been active across the species range and TE activity is homogeneous across populations, indicating the presence of conserved regulatory mechanisms. Second, almost half of the TE insertion polymorphisms are accession-specific, most likely because of recent activity in expanding populations and the action of purifying selection. And finally, although TE insertion polymorphisms are underrepresented in and around genes, more than 1,000 of them occur in genic regions and could thus contribute to functional divergence. Our study shows that while TEs in B. distachyon are “well-behaved” compared with TEs in other species with larger genomes, they are an abundant source of lineage-specific genetic variation and may play an important role in population divergence and adaptation.
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Affiliation(s)
- Christoph Stritt
- Institute for Plant and Microbial Biology, University of Zurich, Switzerland
| | - Sean P Gordon
- DOE Joint Genome Institute, Walnut Creek, California
| | - Thomas Wicker
- Institute for Plant and Microbial Biology, University of Zurich, Switzerland
| | - John P Vogel
- DOE Joint Genome Institute, Walnut Creek, California
| | - Anne C Roulin
- Institute for Plant and Microbial Biology, University of Zurich, Switzerland
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16
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Pasquesi GIM, Adams RH, Card DC, Schield DR, Corbin AB, Perry BW, Reyes-Velasco J, Ruggiero RP, Vandewege MW, Shortt JA, Castoe TA. Squamate reptiles challenge paradigms of genomic repeat element evolution set by birds and mammals. Nat Commun 2018; 9:2774. [PMID: 30018307 PMCID: PMC6050309 DOI: 10.1038/s41467-018-05279-1] [Citation(s) in RCA: 70] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2017] [Accepted: 06/25/2018] [Indexed: 12/14/2022] Open
Abstract
Broad paradigms of vertebrate genomic repeat element evolution have been largely shaped by analyses of mammalian and avian genomes. Here, based on analyses of genomes sequenced from over 60 squamate reptiles (lizards and snakes), we show that patterns of genomic repeat landscape evolution in squamates challenge such paradigms. Despite low variance in genome size, squamate genomes exhibit surprisingly high variation among species in abundance (ca. 25–73% of the genome) and composition of identifiable repeat elements. We also demonstrate that snake genomes have experienced microsatellite seeding by transposable elements at a scale unparalleled among eukaryotes, leading to some snake genomes containing the highest microsatellite content of any known eukaryote. Our analyses of transposable element evolution across squamates also suggest that lineage-specific variation in mechanisms of transposable element activity and silencing, rather than variation in species-specific demography, may play a dominant role in driving variation in repeat element landscapes across squamate phylogeny. Large-scale patterns of genomic repeat element evolution have been studied mainly in birds and mammals. Here, the authors analyze the genomes of over 60 squamate reptiles and show high variation in repeat elements compared to mammals and birds, and particularly high microsatellite seeding in snakes.
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Affiliation(s)
- Giulia I M Pasquesi
- Department of Biology, University of Texas at Arlington, 501S. Nedderman Drive, Arlington, TX, 76019, USA
| | - Richard H Adams
- Department of Biology, University of Texas at Arlington, 501S. Nedderman Drive, Arlington, TX, 76019, USA
| | - Daren C Card
- Department of Biology, University of Texas at Arlington, 501S. Nedderman Drive, Arlington, TX, 76019, USA
| | - Drew R Schield
- Department of Biology, University of Texas at Arlington, 501S. Nedderman Drive, Arlington, TX, 76019, USA
| | - Andrew B Corbin
- Department of Biology, University of Texas at Arlington, 501S. Nedderman Drive, Arlington, TX, 76019, USA
| | - Blair W Perry
- Department of Biology, University of Texas at Arlington, 501S. Nedderman Drive, Arlington, TX, 76019, USA
| | - Jacobo Reyes-Velasco
- Department of Biology, University of Texas at Arlington, 501S. Nedderman Drive, Arlington, TX, 76019, USA.,Department of Biology, New York University Abu Dhabi, Saadiyat Island, United Arab Emirates
| | - Robert P Ruggiero
- Department of Biology, New York University Abu Dhabi, Saadiyat Island, United Arab Emirates
| | - Michael W Vandewege
- Department of Biology, Institute for Genomics and Evolutionary Medicine, Temple University, Philadelphia, PA, 19122, USA
| | - Jonathan A Shortt
- Department of Biochemistry and Molecular Genetics, University of Colorado School of Medicine, Aurora, CO, 80045, USA
| | - Todd A Castoe
- Department of Biology, University of Texas at Arlington, 501S. Nedderman Drive, Arlington, TX, 76019, USA.
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17
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Du H, Fu J, Wang S, Liu H, Zeng Y, Yang J, Xiong S. 1H-NMR metabolomics analysis of nutritional components from two kinds of freshwater fish brain extracts. RSC Adv 2018; 8:19470-19478. [PMID: 35541012 PMCID: PMC9080649 DOI: 10.1039/c8ra02311e] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2018] [Accepted: 05/17/2018] [Indexed: 11/21/2022] Open
Abstract
There are a number of bioactive compounds in freshwater fish brains, and their functional roles have not been clearly elucidated. NMR-based metabolic profiling could enable rapid characterization of the nutritional composition a fish's brain. Here, two kinds of freshwater fish brains were investigated, crucian carp and yellow catfish. A 1H-NMR based metabolomic approach was used to illustrate the nutritional components of these two kinds of brain. At first, the microwave method was utilized to cease the activity of the enzymes in the brain, and the chemicals were extracted for NMR analysis. These two kinds of brain had significant differences in metabolic patterns, and the chemical compositions of the yellow catfish brain were similar to those of rodent and human brains. Furthermore, most of the different metabolites were significantly higher in the yellow catfish, except for acetamide. This study could provide comprehensive information regarding the utilization of fish heads during processing of fish and dietary nutrition guidance. There are a number of bioactive compounds in freshwater fish brains, and their functional roles have not been clearly elucidated. NMR-based metabolic profiling could provide a rapid characterization of a fish brain's nutritional composition.![]()
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Affiliation(s)
- Hongying Du
- College of Food Science and Technology, Huazhong Agricultural University Wuhan Hubei 430070 P. R. China +86-27-87288375.,National R & D Branch Center for Conventional Freshwater Fish Processing Wuhan Hubei 430070 P. R. China
| | - Jialing Fu
- College of Food Science and Technology, Huazhong Agricultural University Wuhan Hubei 430070 P. R. China +86-27-87288375
| | - Siqi Wang
- College of Food Science and Technology, Huazhong Agricultural University Wuhan Hubei 430070 P. R. China +86-27-87288375
| | - Huili Liu
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Key Laboratory of Magnetic Resonance in Biological Systems, Wuhan Center for Magnetic Resonance, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences Wuhan 430071 China
| | - Yongchao Zeng
- College of Food Science and Technology, Huazhong Agricultural University Wuhan Hubei 430070 P. R. China +86-27-87288375
| | - Jiaren Yang
- College of Food Science and Technology, Huazhong Agricultural University Wuhan Hubei 430070 P. R. China +86-27-87288375
| | - Shanbai Xiong
- College of Food Science and Technology, Huazhong Agricultural University Wuhan Hubei 430070 P. R. China +86-27-87288375.,National R & D Branch Center for Conventional Freshwater Fish Processing Wuhan Hubei 430070 P. R. China
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18
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Xue AT, Ruggiero RP, Hickerson MJ, Boissinot S. Differential Effect of Selection against LINE Retrotransposons among Vertebrates Inferred from Whole-Genome Data and Demographic Modeling. Genome Biol Evol 2018; 10:1265-1281. [PMID: 29688421 PMCID: PMC5963298 DOI: 10.1093/gbe/evy083] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/20/2018] [Indexed: 12/30/2022] Open
Abstract
Variation in LINE composition is one of the major determinants for the substantial size and structural differences among vertebrate genomes. In particular, the larger genomes of mammals are characterized by hundreds of thousands of copies from a single LINE clade, L1, whereas nonmammalian vertebrates possess a much greater diversity of LINEs, yet with orders of magnitude less in copy number. It has been proposed that such variation in copy number among vertebrates is due to differential effect of LINE insertions on host fitness. To investigate LINE selection, we deployed a framework of demographic modeling, coalescent simulations, and probabilistic inference against population-level whole-genome data sets for four model species: one population each of threespine stickleback, green anole, and house mouse, as well as three human populations. Specifically, we inferred a null demographic background utilizing SNP data, which was then exploited to simulate a putative null distribution of summary statistics that was compared with LINE data. Subsequently, we applied the inferred null demographic model with an additional exponential size change parameter, coupled with model selection, to test for neutrality as well as estimate the strength of either negative or positive selection. We found a robust signal for purifying selection in anole and mouse, but a lack of clear evidence for selection in stickleback and human. Overall, we demonstrated LINE insertion dynamics that are not in accordance to a mammalian versus nonmammalian dichotomy, and instead the degree of existing LINE activity together with host-specific demographic history may be the main determinants of LINE abundance.
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Affiliation(s)
- Alexander T Xue
- Department of Biology: Subprogram in Ecology, Evolutionary Biology, and Behavior, City College and Graduate Center of City University of New York
- Human Genetics Institute of New Jersey and Department of Genetics, Rutgers University, Piscataway
| | - Robert P Ruggiero
- New York University Abu Dhabi, Saadiyat Island Campus, United Arab Emirates
| | - Michael J Hickerson
- Department of Biology: Subprogram in Ecology, Evolutionary Biology, and Behavior, City College and Graduate Center of City University of New York
- Division of Invertebrate Zoology, American Museum of Natural History, New York, New York
| | - Stéphane Boissinot
- New York University Abu Dhabi, Saadiyat Island Campus, United Arab Emirates
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19
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Sookdeo A, Hepp CM, Boissinot S. Contrasted patterns of evolution of the LINE-1 retrotransposon in perissodactyls: the history of a LINE-1 extinction. Mob DNA 2018; 9:12. [PMID: 29610583 PMCID: PMC5872511 DOI: 10.1186/s13100-018-0117-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Accepted: 03/22/2018] [Indexed: 12/30/2022] Open
Abstract
Background LINE-1 (L1) is the dominant autonomously replicating non-LTR retrotransposon in mammals. Although our knowledge of L1 evolution across the tree of life has considerably improved in recent years, what we know of L1 evolution in mammals is biased and comes mostly from studies in primates (mostly human) and rodents (mostly mouse). It is unclear if patterns of evolution that are shared between those two groups apply to other mammalian orders. Here we performed a detailed study on the evolution of L1 in perissodactyls by making use of the complete genome of the domestic horse and of the white rhinoceros. This mammalian order offers an excellent model to study the extinction of L1 since the rhinoceros is one of the few mammalian species to have lost active L1. Results We found that multiple L1 lineages, carrying different 5’UTRs, have been simultaneously active during the evolution of perissodactyls. We also found that L1 has continuously amplified and diversified in horse. In rhinoceros, L1 was very prolific early on. Two successful families were simultaneously active until ~20my ago but became extinct suddenly at exactly the same time. Conclusions The general pattern of L1 evolution in perissodactyls is very similar to what was previously described in mouse and human, suggesting some commonalities in the way mammalian genomes interact with L1. We confirmed the extinction of L1 in rhinoceros and we discuss several possible mechanisms. Electronic supplementary material The online version of this article (10.1186/s13100-018-0117-4) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Akash Sookdeo
- 1Department of Biology, New York University, New York, NY USA
| | - Crystal M Hepp
- 2School of Informatics, Computing, and Cyber Systems, Northern Arizona University, Flagstaff, AZ USA
| | - Stéphane Boissinot
- 3New York University Abu Dhabi, Saadiyat Island, Abu Dhabi, United Arab Emirates
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20
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Tollis M, Hutchins ED, Stapley J, Rupp SM, Eckalbar WL, Maayan I, Lasku E, Infante CR, Dennis SR, Robertson JA, May CM, Crusoe MR, Bermingham E, DeNardo DF, Hsieh STT, Kulathinal RJ, McMillan WO, Menke DB, Pratt SC, Rawls JA, Sanjur O, Wilson-Rawls J, Wilson Sayres MA, Fisher RE, Kusumi K. Comparative Genomics Reveals Accelerated Evolution in Conserved Pathways during the Diversification of Anole Lizards. Genome Biol Evol 2018; 10:489-506. [PMID: 29360978 PMCID: PMC5798147 DOI: 10.1093/gbe/evy013] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/17/2018] [Indexed: 11/21/2022] Open
Abstract
Squamates include all lizards and snakes, and display some of the most diverse and extreme morphological adaptations among vertebrates. However, compared with birds and mammals, relatively few resources exist for comparative genomic analyses of squamates, hampering efforts to understand the molecular bases of phenotypic diversification in such a speciose clade. In particular, the ∼400 species of anole lizard represent an extensive squamate radiation. Here, we sequence and assemble the draft genomes of three anole species-Anolis frenatus, Anolis auratus, and Anolis apletophallus-for comparison with the available reference genome of Anolis carolinensis. Comparative analyses reveal a rapid background rate of molecular evolution consistent with a model of punctuated equilibrium, and strong purifying selection on functional genomic elements in anoles. We find evidence for accelerated evolution in genes involved in behavior, sensory perception, and reproduction, as well as in genes regulating limb bud development and hindlimb specification. Morphometric analyses of anole fore and hindlimbs corroborated these findings. We detect signatures of positive selection across several genes related to the development and regulation of the forebrain, hormones, and the iguanian lizard dewlap, suggesting molecular changes underlying behavioral adaptations known to reinforce species boundaries were a key component in the diversification of anole lizards.
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Affiliation(s)
- Marc Tollis
- School of Life Sciences, Arizona State University
- Virginia G. Piper Center for Personalized Diagnostics, The Biodesign Institute at Arizona State University
| | - Elizabeth D Hutchins
- School of Life Sciences, Arizona State University
- Neurogenomics Division, Translational Genomics Research Institute, Phoenix, Arizona
| | - Jessica Stapley
- Smithsonian Tropical Research Institute, Panamá, República de Panamá
| | - Shawn M Rupp
- School of Life Sciences, Arizona State University
| | | | - Inbar Maayan
- School of Life Sciences, Arizona State University
| | - Eris Lasku
- School of Life Sciences, Arizona State University
| | - Carlos R Infante
- Department of Genetics, University of Georgia
- Department of Molecular and Cellular Biology, University of Arizona
| | - Stuart R Dennis
- Smithsonian Tropical Research Institute, Panamá, República de Panamá
| | | | | | | | - Eldredge Bermingham
- Smithsonian Tropical Research Institute, Panamá, República de Panamá
- Patricia and Phillip Frost Museum of Science, Miami, Florida
| | | | | | | | | | | | | | | | - Oris Sanjur
- Smithsonian Tropical Research Institute, Panamá, República de Panamá
| | | | - Melissa A Wilson Sayres
- School of Life Sciences, Arizona State University
- The Center for Evolution and Medicine, Arizona State University
| | - Rebecca E Fisher
- School of Life Sciences, Arizona State University
- Department of Basic Medical Sciences, University of Arizona College of Medicine–Phoenix
| | - Kenro Kusumi
- School of Life Sciences, Arizona State University
- Neurogenomics Division, Translational Genomics Research Institute, Phoenix, Arizona
- Department of Basic Medical Sciences, University of Arizona College of Medicine–Phoenix
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