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Gopalan SS, Perry BW, Francioli YZ, Schield DR, Guss HD, Bernstein JM, Ballard K, Smith CF, Saviola AJ, Adams RH, Mackessy SP, Castoe TA. Diverse Gene Regulatory Mechanisms Alter Rattlesnake Venom Gene Expression at Fine Evolutionary Scales. Genome Biol Evol 2024; 16:evae110. [PMID: 38753011 PMCID: PMC11243404 DOI: 10.1093/gbe/evae110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/08/2024] [Indexed: 07/13/2024] Open
Abstract
Understanding and predicting the relationships between genotype and phenotype is often challenging, largely due to the complex nature of eukaryotic gene regulation. A step towards this goal is to map how phenotypic diversity evolves through genomic changes that modify gene regulatory interactions. Using the Prairie Rattlesnake (Crotalus viridis) and related species, we integrate mRNA-seq, proteomic, ATAC-seq and whole-genome resequencing data to understand how specific evolutionary modifications to gene regulatory network components produce differences in venom gene expression. Through comparisons within and between species, we find a remarkably high degree of gene expression and regulatory network variation across even a shallow level of evolutionary divergence. We use these data to test hypotheses about the roles of specific trans-factors and cis-regulatory elements, how these roles may vary across venom genes and gene families, and how variation in regulatory systems drive diversity in venom phenotypes. Our results illustrate that differences in chromatin and genotype at regulatory elements play major roles in modulating expression. However, we also find that enhancer deletions, differences in transcription factor expression, and variation in activity of the insulator protein CTCF also likely impact venom phenotypes. Our findings provide insight into the diversity and gene-specificity of gene regulatory features and highlight the value of comparative studies to link gene regulatory network variation to phenotypic variation.
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Affiliation(s)
- Siddharth S Gopalan
- Department of Biology, University of Texas at Arlington, Arlington, TX 76019, USA
| | - Blair W Perry
- Department of Biology, University of Texas at Arlington, Arlington, TX 76019, USA
- School of Biological Sciences, Washington State University, Pullman, WA 99164, USA
| | - Yannick Z Francioli
- Department of Biology, University of Texas at Arlington, Arlington, TX 76019, USA
| | - Drew R Schield
- Department of Biology, University of Virginia, Charlottesville, VA 22903, USA
| | - Hannah D Guss
- Department of Biology, University of Texas at Arlington, Arlington, TX 76019, USA
| | - Justin M Bernstein
- Department of Biology, University of Texas at Arlington, Arlington, TX 76019, USA
| | - Kaas Ballard
- Department of Biology, University of Texas at Arlington, Arlington, TX 76019, USA
| | - Cara F Smith
- Department of Biochemistry and Molecular Genetics, University of Colorado Denver, Aurora, CO 80045, USA
| | - Anthony J Saviola
- Department of Biochemistry and Molecular Genetics, University of Colorado Denver, Aurora, CO 80045, USA
| | - Richard H Adams
- Department of Entomology and Plant Pathology, University of Arkansas Agricultural Experimental Station, University of Arkansas, Fayetteville, AR 72701, USA
| | - Stephen P Mackessy
- Department of Biological Sciences, University of Northern Colorado, Greeley, CO 80639, USA
| | - Todd A Castoe
- Department of Biology, University of Texas at Arlington, Arlington, TX 76019, USA
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2
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Jay P, Jeffries D, Hartmann FE, Véber A, Giraud T. Why do sex chromosomes progressively lose recombination? Trends Genet 2024; 40:564-579. [PMID: 38677904 DOI: 10.1016/j.tig.2024.03.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Revised: 03/18/2024] [Accepted: 03/19/2024] [Indexed: 04/29/2024]
Abstract
Progressive recombination loss is a common feature of sex chromosomes. Yet, the evolutionary drivers of this phenomenon remain a mystery. For decades, differences in trait optima between sexes (sexual antagonism) have been the favoured hypothesis, but convincing evidence is lacking. Recent years have seen a surge of alternative hypotheses to explain progressive extensions and maintenance of recombination suppression: neutral accumulation of sequence divergence, selection of nonrecombining fragments with fewer deleterious mutations than average, sheltering of recessive deleterious mutations by linkage to heterozygous alleles, early evolution of dosage compensation, and constraints on recombination restoration. Here, we explain these recent hypotheses and dissect their assumptions, mechanisms, and predictions. We also review empirical studies that have brought support to the various hypotheses.
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Affiliation(s)
- Paul Jay
- Center for GeoGenetics, University of Copenhagen, Copenhagen, Denmark; Université Paris-Saclay, CNRS, AgroParisTech, Laboratoire Ecologie Systématique et Evolution, UMR 8079, Bâtiment 680, 12 route RD128, 91190 Gif-sur-Yvette, France.
| | - Daniel Jeffries
- Division of Evolutionary Ecology, Institute of Ecology and Evolution, University of Bern, 3012 Bern, Switzerland
| | - Fanny E Hartmann
- Université Paris-Saclay, CNRS, AgroParisTech, Laboratoire Ecologie Systématique et Evolution, UMR 8079, Bâtiment 680, 12 route RD128, 91190 Gif-sur-Yvette, France
| | - Amandine Véber
- Université Paris Cité, CNRS, MAP5, F-75006 Paris, France
| | - Tatiana Giraud
- Université Paris-Saclay, CNRS, AgroParisTech, Laboratoire Ecologie Systématique et Evolution, UMR 8079, Bâtiment 680, 12 route RD128, 91190 Gif-sur-Yvette, France
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3
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Myers EA, Rautsaw RM, Borja M, Jones J, Grünwald CI, Holding ML, Grazziotin F, Parkinson CL. Phylogenomic discordance is driven by wide-spread introgression and incomplete lineage sorting during rapid species diversification within rattlesnakes (Viperidae: Crotalus and Sistrurus). Syst Biol 2024:syae018. [PMID: 38695290 DOI: 10.1093/sysbio/syae018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Indexed: 08/11/2024] Open
Abstract
Phylogenomics allows us to uncover the historical signal of evolutionary processes through time and estimate phylogenetic networks accounting for these signals. Insight from genome-wide data further allows us to pinpoint the contributions to phylogenetic signal from hybridization, introgression, and ancestral polymorphism across the genome. Here we focus on how these processes have contributed to phylogenetic discordance among rattlesnakes (genera Crotalus and Sistrurus), a group for which there are numerous conflicting phylogenetic hypotheses based on a diverse array of molecular datasets and analytical methods. We address the instability of the rattlesnake phylogeny using genomic data generated from transcriptomes sampled from nearly all known species. These genomic data, analyzed with coalescent and network-based approaches, reveal numerous instances of rapid speciation where individual gene trees conflict with the species tree. Moreover, the evolutionary history of rattlesnakes is dominated by incomplete speciation and frequent hybridization, both of which have likely influenced past interpretations of phylogeny. We present a new framework in which the evolutionary relationships of this group can only be understood in light of genome-wide data and network-based analytical methods. Our data suggest that network radiations, like seen within the rattlesnakes, can only be understood in a phylogenomic context, necessitating similar approaches in our attempts to understand evolutionary history in other rapidly radiating species.
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Affiliation(s)
- Edward A Myers
- Department of Biological Sciences, Clemson University, Clemson, SC 29634, USA
- Department of Herpetology, California Academy of Sciences, San Francisco, CA 94118, USA
| | - Rhett M Rautsaw
- Department of Biological Sciences, Clemson University, Clemson, SC 29634, USA
| | - Miguel Borja
- Facultad de Ciencias Biológicas, Universdad Juárez del Estado de Durango, Av. Universidad s/n. Fracc. Filadelfia, Gómez Palacio, Durango., Mex
| | - Jason Jones
- Herp.mx A.C. C.P. 28989, Villa de Álvarez, Colima, Mexico
| | - Christoph I Grünwald
- Herp.mx A.C. C.P. 28989, Villa de Álvarez, Colima, Mexico
- Biodiversa A.C., Avenida de la Ribera #203, C.P. 45900, Chapala, Jalisco, Mexico
| | - Matthew L Holding
- Department of Biological Sciences, Clemson University, Clemson, SC 29634, USA
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, USA
| | - Felipe Grazziotin
- Laboratório Especial de Coleções Zoológicas, Instituto Butantan, Avenida Vital Brasil, São Paulo, 05503-900, Brazil
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4
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Hogan MP, Holding ML, Nystrom GS, Colston TJ, Bartlett DA, Mason AJ, Ellsworth SA, Rautsaw RM, Lawrence KC, Strickland JL, He B, Fraser P, Margres MJ, Gilbert DM, Gibbs HL, Parkinson CL, Rokyta DR. The genetic regulatory architecture and epigenomic basis for age-related changes in rattlesnake venom. Proc Natl Acad Sci U S A 2024; 121:e2313440121. [PMID: 38578985 PMCID: PMC11032440 DOI: 10.1073/pnas.2313440121] [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: 08/08/2023] [Accepted: 03/13/2024] [Indexed: 04/07/2024] Open
Abstract
Developmental phenotypic changes can evolve under selection imposed by age- and size-related ecological differences. Many of these changes occur through programmed alterations to gene expression patterns, but the molecular mechanisms and gene-regulatory networks underlying these adaptive changes remain poorly understood. Many venomous snakes, including the eastern diamondback rattlesnake (Crotalus adamanteus), undergo correlated changes in diet and venom expression as snakes grow larger with age, providing models for identifying mechanisms of timed expression changes that underlie adaptive life history traits. By combining a highly contiguous, chromosome-level genome assembly with measures of expression, chromatin accessibility, and histone modifications, we identified cis-regulatory elements and trans-regulatory factors controlling venom ontogeny in the venom glands of C. adamanteus. Ontogenetic expression changes were significantly correlated with epigenomic changes within genes, immediately adjacent to genes (e.g., promoters), and more distant from genes (e.g., enhancers). We identified 37 candidate transcription factors (TFs), with the vast majority being up-regulated in adults. The ontogenetic change is largely driven by an increase in the expression of TFs associated with growth signaling, transcriptional activation, and circadian rhythm/biological timing systems in adults with corresponding epigenomic changes near the differentially expressed venom genes. However, both expression activation and repression contributed to the composition of both adult and juvenile venoms, demonstrating the complexity and potential evolvability of gene regulation for this trait. Overall, given that age-based trait variation is common across the tree of life, we provide a framework for understanding gene-regulatory-network-driven life-history evolution more broadly.
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Affiliation(s)
- Michael P. Hogan
- Department of Biological Science, Florida State University, Tallahassee, FL32306
| | - Matthew L. Holding
- Department of Biological Science, Florida State University, Tallahassee, FL32306
- Life Sciences Institute, University of Michigan, Ann Arbor, MI48109
| | - Gunnar S. Nystrom
- Department of Biological Science, Florida State University, Tallahassee, FL32306
| | - Timothy J. Colston
- Department of Biological Science, Florida State University, Tallahassee, FL32306
- Department of Biology, University of Puerto Rico at Mayagüez, Mayagüez, PR00681
| | - Daniel A. Bartlett
- Department of Biological Science, Florida State University, Tallahassee, FL32306
| | - Andrew J. Mason
- Department of Biological Sciences, Clemson University, Clemson, SC29634
- Department of Evolution, Ecology and Organismal Biology, The Ohio State University, Columbus, OH43210
| | - Schyler A. Ellsworth
- Department of Biological Science, Florida State University, Tallahassee, FL32306
| | - Rhett M. Rautsaw
- Department of Biological Sciences, Clemson University, Clemson, SC29634
- Department of Integrative Biology, University of South Florida, Tampa, FL33620
- School of Biological Sciences, Washington State University, Pullman, WA99164
| | - Kylie C. Lawrence
- Department of Biological Science, Florida State University, Tallahassee, FL32306
| | - Jason L. Strickland
- Department of Biological Sciences, Clemson University, Clemson, SC29634
- Department of Biology, University of South Alabama, Mobile, AL36688
| | - Bing He
- Department of Biological Science, Florida State University, Tallahassee, FL32306
| | - Peter Fraser
- Department of Biological Science, Florida State University, Tallahassee, FL32306
| | - Mark J. Margres
- Department of Integrative Biology, University of South Florida, Tampa, FL33620
| | - David M. Gilbert
- Laboratory of Chromosome Replication and Epigenome Regulation, San Diego Biomedical Research Institute, San Diego, CA92121
| | - H. Lisle Gibbs
- Department of Evolution, Ecology and Organismal Biology, The Ohio State University, Columbus, OH43210
| | - Christopher L. Parkinson
- Department of Biological Sciences, Clemson University, Clemson, SC29634
- Department of Forestry and Environmental Conservation, Clemson University, Clemson, SC29634
| | - Darin R. Rokyta
- Department of Biological Science, Florida State University, Tallahassee, FL32306
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5
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Uno Y, Matsubara K. Unleashing diversity through flexibility: The evolutionary journey of sex chromosomes in amphibians and reptiles. JOURNAL OF EXPERIMENTAL ZOOLOGY. PART A, ECOLOGICAL AND INTEGRATIVE PHYSIOLOGY 2024; 341:230-241. [PMID: 38155517 DOI: 10.1002/jez.2776] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Revised: 12/01/2023] [Accepted: 12/05/2023] [Indexed: 12/30/2023]
Abstract
Sex determination systems have greatly diversified between amphibians and reptiles, with such as the different sex chromosome compositions within a single species and transition between temperature-dependent sex determination (TSD) and genetic sex determination (GSD). In most sex chromosome studies on amphibians and reptiles, the whole-genome sequence of Xenopous tropicalis and chicken have been used as references to compare the chromosome homology of sex chromosomes among each of these taxonomic groups, respectively. In the present study, we reviewed existing reports on sex chromosomes, including karyotypes, in amphibians and reptiles. Furthermore, we compared the identified genetic linkages of sex chromosomes in amphibians and reptiles with the chicken genome as a reference, which is believed to resemble the ancestral tetrapod karyotype. Our findings revealed that sex chromosomes in amphibians are derived from genetic linkages homologous to various chicken chromosomes, even among several frogs within single families, such as Ranidae and Pipidae. In contrast, sex chromosomes in reptiles exhibit conserved genetic linkages with chicken chromosomes, not only across most species within a single family, but also within closely related families. The diversity of sex chromosomes in amphibians and reptiles may be attributed to the flexibility of their sex determination systems, including the ease of sex reversal in these animals.
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Affiliation(s)
- Yoshinobu Uno
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Tokyo, Japan
| | - Kazumi Matsubara
- Department of Bioscience and Biotechnology, Graduate School of Bioscience and Biotechnology, Chubu University, Kasugai, Aichi, Japan
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Webster TH, Vannan A, Pinto BJ, Denbrock G, Morales M, Dolby GA, Fiddes IT, DeNardo DF, Wilson MA. Lack of Dosage Balance and Incomplete Dosage Compensation in the ZZ/ZW Gila Monster (Heloderma suspectum) Revealed by De Novo Genome Assembly. Genome Biol Evol 2024; 16:evae018. [PMID: 38319079 PMCID: PMC10950046 DOI: 10.1093/gbe/evae018] [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: 06/15/2023] [Revised: 01/23/2024] [Accepted: 01/23/2024] [Indexed: 02/07/2024] Open
Abstract
Reptiles exhibit a variety of modes of sex determination, including both temperature-dependent and genetic mechanisms. Among those species with genetic sex determination, sex chromosomes of varying heterogamety (XX/XY and ZZ/ZW) have been observed with different degrees of differentiation. Karyotype studies have demonstrated that Gila monsters (Heloderma suspectum) have ZZ/ZW sex determination and this system is likely homologous to the ZZ/ZW system in the Komodo dragon (Varanus komodoensis), but little else is known about their sex chromosomes. Here, we report the assembly and analysis of the Gila monster genome. We generated a de novo draft genome assembly for a male using 10X Genomics technology. We further generated and analyzed short-read whole genome sequencing and whole transcriptome sequencing data for three males and three females. By comparing female and male genomic data, we identified four putative Z chromosome scaffolds. These putative Z chromosome scaffolds are homologous to Z-linked scaffolds identified in the Komodo dragon. Further, by analyzing RNAseq data, we observed evidence of incomplete dosage compensation between the Gila monster Z chromosome and autosomes and a lack of balance in Z-linked expression between the sexes. In particular, we observe lower expression of the Z in females (ZW) than males (ZZ) on a global basis, though we find evidence suggesting local gene-by-gene compensation. This pattern has been observed in most other ZZ/ZW systems studied to date and may represent a general pattern for female heterogamety in vertebrates.
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Affiliation(s)
- Timothy H Webster
- Department of Anthropology, University of Utah, Salt Lake City, UT, USA
- School of Life Sciences, Arizona State University, Tempe, AZ, USA
| | - Annika Vannan
- School of Life Sciences, Arizona State University, Tempe, AZ, USA
| | - 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
| | - Grant Denbrock
- School of Life Sciences, Arizona State University, Tempe, AZ, USA
| | - Matheo Morales
- School of Life Sciences, Arizona State University, Tempe, AZ, USA
- Department of Genetics, Yale University, New Haven, CT, USA
| | - Greer A Dolby
- School of Life Sciences, Arizona State University, Tempe, AZ, USA
- Department of Biology, University of Alabama at Birmingham, Birmingham, AL, USA
| | | | - Dale F DeNardo
- School of Life Sciences, Arizona State University, Tempe, AZ, 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
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7
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Hoge C, de Manuel M, Mahgoub M, Okami N, Fuller Z, Banerjee S, Baker Z, McNulty M, Andolfatto P, Macfarlan TS, Schumer M, Tzika AC, Przeworski M. Patterns of recombination in snakes reveal a tug-of-war between PRDM9 and promoter-like features. Science 2024; 383:eadj7026. [PMID: 38386752 DOI: 10.1126/science.adj7026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2023] [Accepted: 01/04/2024] [Indexed: 02/24/2024]
Abstract
In some mammals, notably humans, recombination occurs almost exclusively where the protein PRDM9 binds, whereas in vertebrates lacking an intact PRDM9, such as birds and canids, recombination rates are elevated near promoter-like features. To determine whether PRDM9 directs recombination in nonmammalian vertebrates, we focused on an exemplar species with a single, intact PRDM9 ortholog, the corn snake (Pantherophis guttatus). Analyzing historical recombination rates along the genome and crossovers in pedigrees, we found evidence that PRDM9 specifies the location of recombination events, but we also detected a separable effect of promoter-like features. These findings reveal that the uses of PRDM9 and promoter-like features need not be mutually exclusive and instead reflect a tug-of-war that is more even in some species than others.
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Affiliation(s)
- Carla Hoge
- Department of Biological Sciences, Columbia University, New York, NY, USA
| | - Marc de Manuel
- Department of Biological Sciences, Columbia University, New York, NY, USA
| | - Mohamed Mahgoub
- The Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - Naima Okami
- Department of Biological Sciences, Columbia University, New York, NY, USA
| | - Zachary Fuller
- Department of Biological Sciences, Columbia University, New York, NY, USA
| | - Shreya Banerjee
- Department of Biology, Stanford University, Stanford, CA, USA
| | - Zachary Baker
- Department of Systems Biology, Columbia University, New York, NY, USA
| | - Morgan McNulty
- Department of Biological Sciences, Columbia University, New York, NY, USA
| | - Peter Andolfatto
- Department of Biological Sciences, Columbia University, New York, NY, USA
| | - Todd S Macfarlan
- The Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - Molly Schumer
- Department of Biology, Stanford University, Stanford, CA, USA
- Howard Hughes Medical Institute, Stanford, CA, USA
| | - Athanasia C Tzika
- Laboratory of Artificial & Natural Evolution (LANE), Department of Genetics & Evolution, University of Geneva, Geneva, Switzerland
| | - Molly Przeworski
- Department of Biological Sciences, Columbia University, New York, NY, USA
- Department of Systems Biology, Columbia University, New York, NY, USA
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8
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Modahl CM, Han SX, van Thiel J, Vaz C, Dunstan NL, Frietze S, Jackson TNW, Mackessy SP, Kini RM. Distinct regulatory networks control toxin gene expression in elapid and viperid snakes. BMC Genomics 2024; 25:186. [PMID: 38365592 PMCID: PMC10874052 DOI: 10.1186/s12864-024-10090-y] [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: 07/28/2023] [Accepted: 02/05/2024] [Indexed: 02/18/2024] Open
Abstract
BACKGROUND Venom systems are ideal models to study genetic regulatory mechanisms that underpin evolutionary novelty. Snake venom glands are thought to share a common origin, but there are major distinctions between venom toxins from the medically significant snake families Elapidae and Viperidae, and toxin gene regulatory investigations in elapid snakes have been limited. Here, we used high-throughput RNA-sequencing to profile gene expression and microRNAs between active (milked) and resting (unmilked) venom glands in an elapid (Eastern Brown Snake, Pseudonaja textilis), in addition to comparative genomics, to identify cis- and trans-acting regulation of venom production in an elapid in comparison to viperids (Crotalus viridis and C. tigris). RESULTS Although there is conservation in high-level mechanistic pathways regulating venom production (unfolded protein response, Notch signaling and cholesterol homeostasis), there are differences in the regulation of histone methylation enzymes, transcription factors, and microRNAs in venom glands from these two snake families. Histone methyltransferases and transcription factor (TF) specificity protein 1 (Sp1) were highly upregulated in the milked elapid venom gland in comparison to the viperids, whereas nuclear factor I (NFI) TFs were upregulated after viperid venom milking. Sp1 and NFI cis-regulatory elements were common to toxin gene promoter regions, but many unique elements were also present between elapid and viperid toxins. The presence of Sp1 binding sites across multiple elapid toxin gene promoter regions that have been experimentally determined to regulate expression, in addition to upregulation of Sp1 after venom milking, suggests this transcription factor is involved in elapid toxin expression. microRNA profiles were distinctive between milked and unmilked venom glands for both snake families, and microRNAs were predicted to target a diversity of toxin transcripts in the elapid P. textilis venom gland, but only snake venom metalloproteinase transcripts in the viperid C. viridis venom gland. These results suggest differences in toxin gene posttranscriptional regulation between the elapid P. textilis and viperid C. viridis. CONCLUSIONS Our comparative transcriptomic and genomic analyses between toxin genes and isoforms in elapid and viperid snakes suggests independent toxin regulation between these two snake families, demonstrating multiple different regulatory mechanisms underpin a venomous phenotype.
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Affiliation(s)
- Cassandra M Modahl
- Department of Biological Sciences, Faculty of Science, National University of Singapore, Singapore, Singapore.
- Centre for Snakebite Research and Interventions, Liverpool School of Tropical Medicine, Liverpool, U.K..
| | - Summer Xia Han
- Department of Biological Sciences, Faculty of Science, National University of Singapore, Singapore, Singapore
- Fulcrum Therapeutics, Cambridge, MA, U.S.A
| | - Jory van Thiel
- Centre for Snakebite Research and Interventions, Liverpool School of Tropical Medicine, Liverpool, U.K
- Institute of Biology Leiden, Leiden University, Leiden, The Netherlands
| | - Candida Vaz
- Human Development, Institute for Clinical Sciences (SICS), Agency for Science, Technology and Research (A*STAR), Singapore, Singapore
| | | | - Seth Frietze
- Department of Biomedical and Health Sciences, University of Vermont, Burlington, VT, U.S.A
| | - Timothy N W Jackson
- Australian Venom Research Unit, Department of Biochemistry and Pharmacology, University of Melbourne, Melbourne, Australia
| | - Stephen P Mackessy
- Department of Biological Sciences, University of Northern Colorado, Greeley, CO, U.S.A
| | - R Manjunatha Kini
- Department of Biological Sciences, Faculty of Science, National University of Singapore, Singapore, Singapore.
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.
- Singapore Eye Research Institute, Singapore, Singapore.
- Department of Biochemistry and Molecular Biology, Virginia Commonwealth University, Richmond, VA, U.S.A..
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9
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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.
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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.)
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10
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Nachtigall PG, Durham AM, Rokyta DR, Junqueira-de-Azevedo ILM. ToxCodAn-Genome: an automated pipeline for toxin-gene annotation in genome assembly of venomous lineages. Gigascience 2024; 13:giad116. [PMID: 38241143 PMCID: PMC10797961 DOI: 10.1093/gigascience/giad116] [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: 07/14/2023] [Revised: 10/19/2023] [Accepted: 12/18/2023] [Indexed: 01/21/2024] Open
Abstract
BACKGROUND The rapid development of sequencing technologies resulted in a wide expansion of genomics studies using venomous lineages. This facilitated research focusing on understanding the evolution of adaptive traits and the search for novel compounds that can be applied in agriculture and medicine. However, the toxin annotation of genomes is a laborious and time-consuming task, and no consensus pipeline is currently available. No computational tool currently exists to address the challenges specific to toxin annotation and to ensure the reproducibility of the process. RESULTS Here, we present ToxCodAn-Genome, the first software designed to perform automated toxin annotation in genomes of venomous lineages. This pipeline was designed to retrieve the full-length coding sequences of toxins and to allow the detection of novel truncated paralogs and pseudogenes. We tested ToxCodAn-Genome using 12 genomes of venomous lineages and achieved high performance on recovering their current toxin annotations. This tool can be easily customized to allow improvements in the final toxin annotation set and can be expanded to virtually any venomous lineage. ToxCodAn-Genome is fast, allowing it to run on any personal computer, but it can also be executed in multicore mode, taking advantage of large high-performance servers. In addition, we provide a guide to direct future research in the venomics field to ensure a confident toxin annotation in the genome being studied. As a case study, we sequenced and annotated the toxin repertoire of Bothrops alternatus, which may facilitate future evolutionary and biomedical studies using vipers as models. CONCLUSIONS ToxCodAn-Genome is suitable to perform toxin annotation in the genome of venomous species and may help to improve the reproducibility of further studies. ToxCodAn-Genome and the guide are freely available at https://github.com/pedronachtigall/ToxCodAn-Genome.
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Affiliation(s)
- Pedro G Nachtigall
- Laboratório de Toxinologia Aplicada, CeTICS, Instituto Butantan, São Paulo, 05503-900 SP, Brazil
- Department of Biological Science, Florida State University, Tallahassee, 32306-4295 FL, USA
| | - Alan M Durham
- Departamento de Ciência da Computação, Instituto de Matemática e Estatística, Universidade de São Paulo (USP), São Paulo, 05508-090 SP, Brazil
| | - Darin R Rokyta
- Department of Biological Science, Florida State University, Tallahassee, 32306-4295 FL, USA
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11
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Westeen EP, Escalona M, Holding ML, Beraut E, Fairbairn C, Marimuthu MPA, Nguyen O, Perri R, Fisher RN, Toffelmier E, Shaffer HB, Wang IJ. A genome assembly for the southern Pacific rattlesnake, Crotalus oreganus helleri, in the western rattlesnake species complex. J Hered 2023; 114:681-689. [PMID: 37493092 PMCID: PMC10650947 DOI: 10.1093/jhered/esad045] [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: 05/09/2023] [Accepted: 07/24/2023] [Indexed: 07/27/2023] Open
Abstract
Rattlesnakes play important roles in their ecosystems by regulating prey populations, are involved in complex coevolutionary dynamics with their prey, and exhibit a variety of unusual adaptations, including maternal care, heat-sensing pit organs, hinged fangs, and medically-significant venoms. The western rattlesnake (Crotalus oreganus) is one of the widest ranging rattlesnake species, with a distribution from British Columbia, where it is listed as threatened, to Baja California and east across the Great Basin to western Wyoming, Colorado and New Mexico. Here, we report a new reference genome assembly for one of six currently recognized subspecies, C. oreganus helleri, as part of the California Conservation Genomics Project (CCGP). Consistent with the reference genomic sequencing strategy of the CCGP, we used Pacific Biosciences HiFi long reads and Hi-C chromatin-proximity sequencing technology to produce a de novo assembled genome. The assembly comprises a total of 698 scaffolds spanning 1,564,812,557 base pairs, has a contig N50 of 64.7 Mb, a scaffold N50 of 110.8 Mb, and BUSCO complete score of 90.5%. This reference genome will be valuable for studies on the genomic basis of venom evolution and variation within Crotalus, in resolving the taxonomy of C. oreganus and its relatives, and for the conservation and management of rattlesnakes in general.
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Affiliation(s)
- Erin P Westeen
- Department of Environmental Science, Policy, and Management, University of California, Berkeley, CA 94720, United States
- Museum of Vertebrate Zoology, University of California, Berkeley, CA 94720, United States
| | - Merly Escalona
- Department of Biomolecular Engineering, University of California Santa Cruz, Santa Cruz, CA 95064, United States
| | - Matthew L Holding
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, United States
| | - Eric Beraut
- Department of Ecology and Evolutionary Biology, University of California, Santa Cruz, Santa Cruz, CA 95064, United States
| | - Colin Fairbairn
- Department of Ecology and Evolutionary Biology, University of California, Santa Cruz, Santa Cruz, CA 95064, United States
| | - Mohan P A Marimuthu
- DNA Technologies and Expression Analysis Core Laboratory, Genome Center, University of California, Davis, CA 95616, United States
| | - Oanh Nguyen
- DNA Technologies and Expression Analysis Core Laboratory, Genome Center, University of California, Davis, CA 95616, United States
| | - Ralph Perri
- 1001 Foothill Drive, Fillmore, CA, 93015, United States
| | - Robert N Fisher
- U.S. Geological Survey, Western Ecological Research Center, San Diego, CA, 92101, United States
| | - Erin Toffelmier
- Department of Ecology and Evolutionary Biology, University of California, Los Angeles, CA 90095, United States
- La Kretz Center for California Conservation Science, Institute of the Environment and Sustainability, University of California, Los Angeles, CA 90095, United States
| | - H Bradley Shaffer
- Department of Ecology and Evolutionary Biology, University of California, Los Angeles, CA 90095, United States
- La Kretz Center for California Conservation Science, Institute of the Environment and Sustainability, University of California, Los Angeles, CA 90095, United States
| | - Ian J Wang
- Department of Environmental Science, Policy, and Management, University of California, Berkeley, CA 94720, United States
- Museum of Vertebrate Zoology, University of California, Berkeley, CA 94720, United States
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12
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Sonoda GG, Tobaruela EDC, Norenburg J, Fabi JP, Andrade SCS. Venomous Noodles: The Evolution of Toxins in Nemertea through Positive Selection and Gene Duplication. Toxins (Basel) 2023; 15:650. [PMID: 37999513 PMCID: PMC10674772 DOI: 10.3390/toxins15110650] [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: 08/30/2023] [Revised: 10/03/2023] [Accepted: 10/11/2023] [Indexed: 11/25/2023] Open
Abstract
Some, probably most and perhaps all, members of the phylum Nemertea are poisonous, documented so far from marine and benthic specimens. Although the toxicity of these animals has been long known, systematic studies on the characterization of toxins, mechanisms of toxicity, and toxin evolution for this group are scarce. Here, we present the first investigation of the molecular evolution of toxins in Nemertea. Using a proteo-transcriptomic approach, we described toxins in the body and poisonous mucus of the pilidiophoran Lineus sanguineus and the hoplonemertean Nemertopsis pamelaroeae. Using these new and publicly available transcriptomes, we investigated the molecular evolution of six selected toxin gene families. In addition, we also characterized in silico the toxin genes found in the interstitial hoplonemertean, Ototyphlonemertes erneba, a meiofaunal taxa. We successfully identified over 200 toxin transcripts in each of these species. Evidence of positive selection and gene duplication was observed in all investigated toxin genes. We hypothesized that the increased rates of gene duplications observed for Pilidiophora could be involved with the expansion of toxin genes. Studies concerning the natural history of Nemertea are still needed to understand the evolution of their toxins. Nevertheless, our results show evolutionary mechanisms similar to other venomous groups.
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Affiliation(s)
- Gabriel Gonzalez Sonoda
- Departamento de Genética e Biologia Evolutiva, IB-Universidade de São Paulo, São Paulo 05508-090, Brazil;
- Instituto Butantan, São Paulo 05503-900, Brazil
| | - Eric de Castro Tobaruela
- Faculdade de Ciências Farmacêuticas, Food Research Center (FoRC), Universidade de São Paulo, São Paulo 05508-080, Brazil; (E.d.C.T.); (J.P.F.)
| | | | - João Paulo Fabi
- Faculdade de Ciências Farmacêuticas, Food Research Center (FoRC), Universidade de São Paulo, São Paulo 05508-080, Brazil; (E.d.C.T.); (J.P.F.)
| | - Sónia C. S. Andrade
- Departamento de Genética e Biologia Evolutiva, IB-Universidade de São Paulo, São Paulo 05508-090, Brazil;
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13
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Camacho MF, Stuginski DR, Andrade-Silva D, Nishiyama-Jr MY, Valente RH, Zelanis A. A snapshot of Bothrops jararaca snake venom gland subcellular proteome. Biochimie 2023; 214:1-10. [PMID: 37315762 DOI: 10.1016/j.biochi.2023.06.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Revised: 05/01/2023] [Accepted: 06/11/2023] [Indexed: 06/16/2023]
Abstract
Snake venom protein synthesis undergoes finely regulated processes in the specialized secretory epithelium within the venom gland. Such processes occur within a defined period in the cell and at specific cellular locations. Thus, the determination of subcellular proteomes allows the characterization of protein groups for which the site may be relevant to their biological roles, thereby allowing the deconvolution of complex biological circuits into functional information. In this regard, we performed subcellular fractionation of proteins from B. jararaca venom gland, focusing on nuclear proteins since this cellular compartment comprises key effectors that shape gene expression. Our results provided a snapshot of B. jararaca's subcellular venom gland proteome and pointed to a 'conserved' proteome core among different life stages (newborn and adult) and between sexes (adult male and female). Overall, the top 15 highly abundant proteins identified in B. jararaca venom glands mirrored the panel of highly expressed genes in human salivary glands. Therefore, the expression profile observed for such a protein set could be considered a conserved core signature of salivary gland secretory epithelium. Moreover, the newborn venom gland displayed a unique expression signature of transcription factors involved in regulating transcription and biosynthetic processes and may mirror biological constraints of the ontogenetic development of B. jararaca, contributing to venom proteome diversity.
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Affiliation(s)
- Maurício Frota Camacho
- Functional Proteomics Laboratory, Institute of Science and Technology, Federal University of São Paulo, UNIFESP, São José dos Campos, SP, 12231-280, Brazil
| | - Daniel R Stuginski
- Laboratory of Herpetology, Butantan Institute, São Paulo, SP, 05503-900, Brazil
| | - Débora Andrade-Silva
- Telomeres Laboratory, Chemical and Biological Sciences Department, IBB-UNESP, Botucatu, São Paulo, Brazil
| | - Milton Y Nishiyama-Jr
- Laboratory of Applied Toxinology, Butantan Institute, Sao Paulo, SP, 05503-900, Brazil
| | - Richard H Valente
- Laboratory of Toxinology, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, FIOCRUZ, Rio de Janeiro, RJ, 21040-900, Brazil
| | - André Zelanis
- Functional Proteomics Laboratory, Institute of Science and Technology, Federal University of São Paulo, UNIFESP, São José dos Campos, SP, 12231-280, Brazil.
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14
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Mathur S, Mason AJ, Bradburd GS, Gibbs HL. Functional genomic diversity is correlated with neutral genomic diversity in populations of an endangered rattlesnake. Proc Natl Acad Sci U S A 2023; 120:e2303043120. [PMID: 37844221 PMCID: PMC10614936 DOI: 10.1073/pnas.2303043120] [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: 02/22/2023] [Accepted: 09/19/2023] [Indexed: 10/18/2023] Open
Abstract
Theory predicts that genetic erosion in small, isolated populations of endangered species can be assessed using estimates of neutral genetic variation, yet this widely used approach has recently been questioned in the genomics era. Here, we leverage a chromosome-level genome assembly of an endangered rattlesnake (Sistrurus catenatus) combined with whole genome resequencing data (N = 110 individuals) to evaluate the relationship between levels of genome-wide neutral and functional diversity over historical and future timescales. As predicted, we found positive correlations between genome-wide estimates of neutral genetic diversity (π) and inferred levels of adaptive variation and an estimate of inbreeding mutation load, and a negative relationship between neutral diversity and an estimate of drift mutation load. However, these correlations were half as strong for projected future levels of neutral diversity based on contemporary effective population sizes. Broadly, our results confirm that estimates of neutral genetic diversity provide an accurate measure of genetic erosion in populations of a threatened vertebrate. They also provide nuance to the neutral-functional diversity controversy by suggesting that while these correlations exist, anthropogenetic impacts may have weakened these associations in the recent past and into the future.
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Affiliation(s)
- Samarth Mathur
- Department of Evolution, Ecology, and Organismal Biology, The Ohio State University, Columbus, OH48824
- Ohio Biodiversity Conservation Partnership, The Ohio State University, Columbus, OH43210
| | - Andrew J. Mason
- Department of Evolution, Ecology, and Organismal Biology, The Ohio State University, Columbus, OH48824
- Ohio Biodiversity Conservation Partnership, The Ohio State University, Columbus, OH43210
| | - Gideon S. Bradburd
- Evolution and Behavior Program, Department of Integrative Biology, Ecology, Michigan State University, East Lansing, MI48824
- Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI48109
| | - H. Lisle Gibbs
- Department of Evolution, Ecology, and Organismal Biology, The Ohio State University, Columbus, OH48824
- Ohio Biodiversity Conservation Partnership, The Ohio State University, Columbus, OH43210
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15
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Smith CF, Nikolakis ZL, Perry BW, Schield DR, Meik JM, Saviola AJ, Castoe TA, Parker J, Mackessy SP. The best of both worlds? Rattlesnake hybrid zones generate complex combinations of divergent venom phenotypes that retain high toxicity. Biochimie 2023; 213:176-189. [PMID: 37451532 DOI: 10.1016/j.biochi.2023.07.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2023] [Revised: 06/27/2023] [Accepted: 07/10/2023] [Indexed: 07/18/2023]
Abstract
Studying the consequences of hybridization between closely related species with divergent traits can reveal patterns of evolution that shape and maintain extreme trophic adaptations. Snake venoms are an excellent model system for examining the evolutionary and ecological patterns that underlie highly selected polymorphic traits. Here we investigate hybrid venom phenotypes that result from natural introgression between two rattlesnake species that express highly divergent venom phenotypes: Crotalus o. concolor and C. v. viridis. Though not yet documented, interbreeding between these species may lead to novel venom phenotypes with unique activities that break the typical trends of venom composition in rattlesnakes. The characteristics of these unusual phenotypes could unveil the roles of introgression in maintaining patterns of venom composition and variation, including the near ubiquitous dichotomy between neurotoxic or degradative venoms observed across rattlesnakes. We use RADseq data to infer patterns of gene flow and hybrid ancestry between these diverged lineages and link these genetic data with analyses of venom composition, biological activity, and whole animal model toxicity tests to understand the impacts of introgression on venom composition. We find that introgressed populations express admixed venom phenotypes that do not sacrifice biological activity (lethal toxicity) or overall abundance of dominant toxins compared to parental venoms. These hybridized venoms therefore do not represent a trade-off in functionality between the typical phenotypic extremes but instead represent a unique combination of characters whose expression appears limited to the hybrid zone.
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Affiliation(s)
- Cara F Smith
- School of Biological Sciences, 501 20th Street, University of Northern Colorado, Greeley, CO, 80639, USA
| | - Zachary L Nikolakis
- Department of Biology, 501 S. Nedderman Drive, University of Texas at Arlington, Arlington, TX, 76019, USA
| | - Blair W Perry
- Department of Biology, 501 S. Nedderman Drive, University of Texas at Arlington, Arlington, TX, 76019, USA
| | - Drew R Schield
- Department of Biology, 501 S. Nedderman Drive, University of Texas at Arlington, Arlington, TX, 76019, USA
| | - Jesse M Meik
- Department of Biological Sciences, Tarleton State University, 1333 W. Washington Street, Stephenville, TX, 76402, USA
| | - Anthony J Saviola
- Department of Biochemistry and Molecular Genetics, 12801 East 17th Avenue, University of Colorado Denver, Aurora, CO, 80045, USA
| | - Todd A Castoe
- Department of Biology, 501 S. Nedderman Drive, University of Texas at Arlington, Arlington, TX, 76019, USA
| | - Joshua Parker
- Fresno City College, 1101 E. University Avenue, Fresno, CA, 93741, USA
| | - Stephen P Mackessy
- School of Biological Sciences, 501 20th Street, University of Northern Colorado, Greeley, CO, 80639, USA.
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16
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Ye X, He C, Yang Y, Sun YH, Xiong S, Chan KC, Si Y, Xiao S, Zhao X, Lin H, Mei Y, Yao Y, Ye G, Wu F, Fang Q. Comprehensive isoform-level analysis reveals the contribution of alternative isoforms to venom evolution and repertoire diversity. Genome Res 2023; 33:1554-1567. [PMID: 37798117 PMCID: PMC10620052 DOI: 10.1101/gr.277707.123] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Accepted: 08/08/2023] [Indexed: 10/07/2023]
Abstract
Animal venom systems have emerged as valuable models for investigating how novel polygenic phenotypes may arise from gene evolution by varying molecular mechanisms. However, a significant portion of venom genes produce alternative mRNA isoforms that have not been extensively characterized, hindering a comprehensive understanding of venom biology. In this study, we present a full-length isoform-level profiling workflow integrating multiple RNA sequencing technologies, allowing us to reconstruct a high-resolution transcriptome landscape of venom genes in the parasitoid wasp Pteromalus puparum Our findings demonstrate that more than half of the venom genes generate multiple isoforms within the venom gland. Through mass spectrometry analysis, we confirm that alternative splicing contributes to the diversity of venom proteins, acting as a mechanism for expanding the venom repertoire. Notably, we identified seven venom genes that exhibit distinct isoform usages between the venom gland and other tissues. Furthermore, evolutionary analyses of venom serpin3 and orcokinin further reveal that the co-option of an ancient isoform and a newly evolved isoform, respectively, contributes to venom recruitment, providing valuable insights into the genetic mechanisms driving venom evolution in parasitoid wasps. Overall, our study presents a comprehensive investigation of venom genes at the isoform level, significantly advancing our understanding of alternative isoforms in venom diversity and evolution and setting the stage for further in-depth research on venoms.
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Affiliation(s)
- Xinhai Ye
- State Key Laboratory of Rice Biology and Breeding & Ministry of Agricultural and Rural Affairs Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Institute of Insect Sciences, Zhejiang University, Hangzhou 310058, China
- Shanghai Institute for Advanced Study, Zhejiang University, Shanghai 201203, China
- College of Computer Science and Technology, Zhejiang University, Hangzhou 310027, China
| | - Chun He
- State Key Laboratory of Rice Biology and Breeding & Ministry of Agricultural and Rural Affairs Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Institute of Insect Sciences, Zhejiang University, Hangzhou 310058, China;
| | - Yi Yang
- State Key Laboratory of Rice Biology and Breeding & Ministry of Agricultural and Rural Affairs Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Institute of Insect Sciences, Zhejiang University, Hangzhou 310058, China
| | - Yu H Sun
- Department of Biology, University of Rochester, Rochester, New York 14627, USA
| | - Shijiao Xiong
- State Key Laboratory of Rice Biology and Breeding & Ministry of Agricultural and Rural Affairs Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Institute of Insect Sciences, Zhejiang University, Hangzhou 310058, China
| | - Kevin C Chan
- Shanghai Institute for Advanced Study, Zhejiang University, Shanghai 201203, China
| | - Yuxuan Si
- College of Computer Science and Technology, Zhejiang University, Hangzhou 310027, China
| | - Shan Xiao
- State Key Laboratory of Rice Biology and Breeding & Ministry of Agricultural and Rural Affairs Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Institute of Insect Sciences, Zhejiang University, Hangzhou 310058, China
| | - Xianxin Zhao
- State Key Laboratory of Rice Biology and Breeding & Ministry of Agricultural and Rural Affairs Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Institute of Insect Sciences, Zhejiang University, Hangzhou 310058, China
| | - Haiwei Lin
- State Key Laboratory of Rice Biology and Breeding & Ministry of Agricultural and Rural Affairs Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Institute of Insect Sciences, Zhejiang University, Hangzhou 310058, China
| | - Yang Mei
- State Key Laboratory of Rice Biology and Breeding & Ministry of Agricultural and Rural Affairs Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Institute of Insect Sciences, Zhejiang University, Hangzhou 310058, China
| | - Yufeng Yao
- Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou 310020, China
| | - Gongyin Ye
- State Key Laboratory of Rice Biology and Breeding & Ministry of Agricultural and Rural Affairs Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Institute of Insect Sciences, Zhejiang University, Hangzhou 310058, China
| | - Fei Wu
- Shanghai Institute for Advanced Study, Zhejiang University, Shanghai 201203, China;
- College of Computer Science and Technology, Zhejiang University, Hangzhou 310027, China
| | - Qi Fang
- State Key Laboratory of Rice Biology and Breeding & Ministry of Agricultural and Rural Affairs Key Laboratory of Molecular Biology of Crop Pathogens and Insects, Institute of Insect Sciences, Zhejiang University, Hangzhou 310058, China;
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17
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Catalán A, Merondun J, Knief U, Wolf JBW. Chromatin accessibility, not 5mC methylation covaries with partial dosage compensation in crows. PLoS Genet 2023; 19:e1010901. [PMID: 37747941 PMCID: PMC10575545 DOI: 10.1371/journal.pgen.1010901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Revised: 10/13/2023] [Accepted: 08/07/2023] [Indexed: 09/27/2023] Open
Abstract
The evolution of genetic sex determination is often accompanied by degradation of the sex-limited chromosome. Male heterogametic systems have evolved convergent, epigenetic mechanisms restoring the resulting imbalance in gene dosage between diploid autosomes (AA) and the hemizygous sex chromosome (X). Female heterogametic systems (AAf Zf, AAm ZZm) tend to only show partial dosage compensation (0.5 < Zf:AAf < 1) and dosage balance (0.5
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Affiliation(s)
- Ana Catalán
- Department of Evolutionary Biology, Evolutionary Biology Centre (EBC), Uppsala University, Uppsala, Sweden
- Division of Evolutionary Biology, LMU Munich, Planegg-Martinsried, Germany
| | - Justin Merondun
- Division of Evolutionary Biology, LMU Munich, Planegg-Martinsried, Germany
| | - Ulrich Knief
- Division of Evolutionary Biology, LMU Munich, Planegg-Martinsried, Germany
- Evolutionary Biology & Ecology,Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Jochen B. W. Wolf
- Department of Evolutionary Biology, Evolutionary Biology Centre (EBC), Uppsala University, Uppsala, Sweden
- Division of Evolutionary Biology, LMU Munich, Planegg-Martinsried, Germany
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18
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Brovkina MV, Chapman MA, Holding ML, Clowney EJ. Emergence and influence of sequence bias in evolutionarily malleable, mammalian tandem arrays. BMC Biol 2023; 21:179. [PMID: 37612705 PMCID: PMC10463633 DOI: 10.1186/s12915-023-01673-4] [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: 04/25/2023] [Accepted: 08/01/2023] [Indexed: 08/25/2023] Open
Abstract
BACKGROUND The radiation of mammals at the extinction of the dinosaurs produced a plethora of new forms-as diverse as bats, dolphins, and elephants-in only 10-20 million years. Behind the scenes, adaptation to new niches is accompanied by extensive innovation in large families of genes that allow animals to contact the environment, including chemosensors, xenobiotic enzymes, and immune and barrier proteins. Genes in these "outward-looking" families are allelically diverse among humans and exhibit tissue-specific and sometimes stochastic expression. RESULTS Here, we show that these tandem arrays of outward-looking genes occupy AT-biased isochores and comprise the "tissue-specific" gene class that lack CpG islands in their promoters. Models of mammalian genome evolution have not incorporated the sharply different functions and transcriptional patterns of genes in AT- versus GC-biased regions. To examine the relationship between gene family expansion, sequence content, and allelic diversity, we use population genetic data and comparative analysis. First, we find that AT bias can emerge during evolutionary expansion of gene families in cis. Second, human genes in AT-biased isochores or with GC-poor promoters experience relatively low rates of de novo point mutation today but are enriched for non-synonymous variants. Finally, we find that isochores containing gene clusters exhibit low rates of recombination. CONCLUSIONS Our analyses suggest that tolerance of non-synonymous variation and low recombination are two forces that have produced the depletion of GC bases in outward-facing gene arrays. In turn, high AT content exerts a profound effect on their chromatin organization and transcriptional regulation.
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Affiliation(s)
- Margarita V Brovkina
- Graduate Program in Cellular and Molecular Biology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Margaret A Chapman
- Neurosciences Graduate Program, University of Michigan Medical School, Ann Arbor, MI, USA
| | | | - E Josephine Clowney
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI, USA.
- Michigan Neuroscience Institute, University of Michigan, Ann Arbor, MI, USA.
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19
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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.
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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
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20
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Peng C, Wu DD, Ren JL, Peng ZL, Ma Z, Wu W, Lv Y, Wang Z, Deng C, Jiang K, Parkinson CL, Qi Y, Zhang ZY, Li JT. Large-scale snake genome analyses provide insights into vertebrate development. Cell 2023; 186:2959-2976.e22. [PMID: 37339633 DOI: 10.1016/j.cell.2023.05.030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Revised: 04/06/2023] [Accepted: 05/19/2023] [Indexed: 06/22/2023]
Abstract
Snakes are a remarkable squamate lineage with unique morphological adaptations, especially those related to the evolution of vertebrate skeletons, organs, and sensory systems. To clarify the genetic underpinnings of snake phenotypes, we assembled and analyzed 14 de novo genomes from 12 snake families. We also investigated the genetic basis of the morphological characteristics of snakes using functional experiments. We identified genes, regulatory elements, and structural variations that have potentially contributed to the evolution of limb loss, an elongated body plan, asymmetrical lungs, sensory systems, and digestive adaptations in snakes. We identified some of the genes and regulatory elements that might have shaped the evolution of vision, the skeletal system and diet in blind snakes, and thermoreception in infrared-sensitive snakes. Our study provides insights into the evolution and development of snakes and vertebrates.
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Affiliation(s)
- Changjun Peng
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization & Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610040, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Dong-Dong Wu
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223, China
| | - Jin-Long Ren
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization & Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610040, China
| | - Zhong-Liang Peng
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization & Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610040, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhifei Ma
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization & Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610040, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Wei Wu
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization & Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610040, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yunyun Lv
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization & Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610040, China; College of Life Science, Neijiang Normal University, Neijiang, Sichuan 641100, China
| | - Zeng Wang
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization & Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610040, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Cao Deng
- Departments of Bioinformatics, DNA Stories Bioinformatics Center, Chengdu 610000, China
| | - Ke Jiang
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization & Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610040, China
| | | | - Yin Qi
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization & Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610040, China
| | - Zhi-Yi Zhang
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization & Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610040, China
| | - Jia-Tang Li
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization & Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610040, China; University of Chinese Academy of Sciences, Beijing 100049, China; Southeast Asia Biodiversity Research Institute, Chinese Academy of Sciences, Yezin, Nay Pyi Taw 05282, Myanmar.
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21
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Gable SM, Mendez JM, Bushroe NA, Wilson A, Byars MI, Tollis M. The State of Squamate Genomics: Past, Present, and Future of Genome Research in the Most Speciose Terrestrial Vertebrate Order. Genes (Basel) 2023; 14:1387. [PMID: 37510292 PMCID: PMC10379679 DOI: 10.3390/genes14071387] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Revised: 06/28/2023] [Accepted: 06/29/2023] [Indexed: 07/30/2023] Open
Abstract
Squamates include more than 11,000 extant species of lizards, snakes, and amphisbaenians, and display a dazzling diversity of phenotypes across their over 200-million-year evolutionary history on Earth. Here, we introduce and define squamates (Order Squamata) and review the history and promise of genomic investigations into the patterns and processes governing squamate evolution, given recent technological advances in DNA sequencing, genome assembly, and evolutionary analysis. We survey the most recently available whole genome assemblies for squamates, including the taxonomic distribution of available squamate genomes, and assess their quality metrics and usefulness for research. We then focus on disagreements in squamate phylogenetic inference, how methods of high-throughput phylogenomics affect these inferences, and demonstrate the promise of whole genomes to settle or sustain persistent phylogenetic arguments for squamates. We review the role transposable elements play in vertebrate evolution, methods of transposable element annotation and analysis, and further demonstrate that through the understanding of the diversity, abundance, and activity of transposable elements in squamate genomes, squamates can be an ideal model for the evolution of genome size and structure in vertebrates. We discuss how squamate genomes can contribute to other areas of biological research such as venom systems, studies of phenotypic evolution, and sex determination. Because they represent more than 30% of the living species of amniote, squamates deserve a genome consortium on par with recent efforts for other amniotes (i.e., mammals and birds) that aim to sequence most of the extant families in a clade.
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Affiliation(s)
- Simone M Gable
- School of Informatics, Computing, and Cyber Systems, Northern Arizona University, Flagstaff, AZ 86011, USA
| | - Jasmine M Mendez
- School of Informatics, Computing, and Cyber Systems, Northern Arizona University, Flagstaff, AZ 86011, USA
| | - Nicholas A Bushroe
- School of Informatics, Computing, and Cyber Systems, Northern Arizona University, Flagstaff, AZ 86011, USA
| | - Adam Wilson
- School of Informatics, Computing, and Cyber Systems, Northern Arizona University, Flagstaff, AZ 86011, USA
| | - Michael I Byars
- School of Informatics, Computing, and Cyber Systems, Northern Arizona University, Flagstaff, AZ 86011, USA
| | - Marc Tollis
- School of Informatics, Computing, and Cyber Systems, Northern Arizona University, Flagstaff, AZ 86011, USA
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22
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Smith CF, Nikolakis ZL, Ivey K, Perry BW, Schield DR, Balchan NR, Parker J, Hansen KC, Saviola AJ, Castoe TA, Mackessy SP. Snakes on a plain: biotic and abiotic factors determine venom compositional variation in a wide-ranging generalist rattlesnake. BMC Biol 2023; 21:136. [PMID: 37280596 DOI: 10.1186/s12915-023-01626-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2022] [Accepted: 05/12/2023] [Indexed: 06/08/2023] Open
Abstract
BACKGROUND Snake venoms are trophic adaptations that represent an ideal model to examine the evolutionary factors that shape polymorphic traits under strong natural selection. Venom compositional variation is substantial within and among venomous snake species. However, the forces shaping this phenotypic complexity, as well as the potential integrated roles of biotic and abiotic factors, have received little attention. Here, we investigate geographic variation in venom composition in a wide-ranging rattlesnake (Crotalus viridis viridis) and contextualize this variation by investigating dietary, phylogenetic, and environmental variables that covary with venom. RESULTS Using shotgun proteomics, venom biochemical profiling, and lethality assays, we identify 2 distinct divergent phenotypes that characterize major axes of venom variation in this species: a myotoxin-rich phenotype and a snake venom metalloprotease (SVMP)-rich phenotype. We find that dietary availability and temperature-related abiotic factors are correlated with geographic trends in venom composition. CONCLUSIONS Our findings highlight the potential for snake venoms to vary extensively within species, for this variation to be driven by biotic and abiotic factors, and for the importance of integrating biotic and abiotic variation for understanding complex trait evolution. Links between venom variation and variation in biotic and abiotic factors indicate that venom variation likely results from substantial geographic variation in selection regimes that determine the efficacy of venom phenotypes across populations and snake species. Our results highlight the cascading influence of abiotic factors on biotic factors that ultimately shape venom phenotype, providing evidence for a central role of local selection as a key driver of venom variation.
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Affiliation(s)
- Cara F Smith
- Department of Biological Sciences, University of Northern Colorado, 501 20th Street, Greeley, CO, 80639, USA
- Department of Biochemistry and Molecular Genetics, University of Colorado Denver, 12801 East 17th Avenue, Aurora, CO, 80045, USA
| | - Zachary L Nikolakis
- Department of Biology, University of Texas at Arlington, 501 S. Nedderman Drive, Arlington, TX, 76019, USA
| | - Kathleen Ivey
- Department of Biology, University of Texas at Arlington, 501 S. Nedderman Drive, Arlington, TX, 76019, USA
| | - Blair W Perry
- Department of Biology, University of Texas at Arlington, 501 S. Nedderman Drive, Arlington, TX, 76019, USA
| | - Drew R Schield
- Department of Biology, University of Texas at Arlington, 501 S. Nedderman Drive, Arlington, TX, 76019, USA
- Current address: Department of Ecology & Evolutionary Biology, University of Colorado, 1900 Pleasant Street, Boulder, CO, 80309, USA
| | - Neil R Balchan
- Department of Biological Sciences, University of Northern Colorado, 501 20th Street, Greeley, CO, 80639, USA
| | - Joshua Parker
- Fresno City College, 1101 E. University Avenue, Fresno, CA, 93741, USA
| | - Kirk C Hansen
- Department of Biochemistry and Molecular Genetics, University of Colorado Denver, 12801 East 17th Avenue, Aurora, CO, 80045, USA
| | - Anthony J Saviola
- Department of Biochemistry and Molecular Genetics, University of Colorado Denver, 12801 East 17th Avenue, Aurora, CO, 80045, USA
| | - Todd A Castoe
- Department of Biology, University of Texas at Arlington, 501 S. Nedderman Drive, Arlington, TX, 76019, USA
| | - Stephen P Mackessy
- Department of Biological Sciences, University of Northern Colorado, 501 20th Street, Greeley, CO, 80639, USA.
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23
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Westfall AK, Gopalan SS, Perry BW, Adams RH, Saviola AJ, Mackessy SP, Castoe TA. Single-Cell Heterogeneity in Snake Venom Expression Is Hardwired by Co-Option of Regulators from Progressively Activated Pathways. Genome Biol Evol 2023; 15:evad109. [PMID: 37311204 PMCID: PMC10289209 DOI: 10.1093/gbe/evad109] [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: 03/06/2023] [Revised: 05/31/2023] [Accepted: 06/07/2023] [Indexed: 06/15/2023] Open
Abstract
The ubiquitous cellular heterogeneity underlying many organism-level phenotypes raises questions about what factors drive this heterogeneity and how these complex heterogeneous systems evolve. Here, we use single-cell expression data from a Prairie rattlesnake (Crotalus viridis) venom gland to evaluate hypotheses for signaling networks underlying snake venom regulation and the degree to which different venom gene families have evolutionarily recruited distinct regulatory architectures. Our findings suggest that snake venom regulatory systems have evolutionarily co-opted trans-regulatory factors from extracellular signal-regulated kinase and unfolded protein response pathways that specifically coordinate expression of distinct venom toxins in a phased sequence across a single population of secretory cells. This pattern of co-option results in extensive cell-to-cell variation in venom gene expression, even between tandemly duplicated paralogs, suggesting this regulatory architecture has evolved to circumvent cellular constraints. While the exact nature of such constraints remains an open question, we propose that such regulatory heterogeneity may circumvent steric constraints on chromatin, cellular physiological constraints (e.g., endoplasmic reticulum stress or negative protein-protein interactions), or a combination of these. Regardless of the precise nature of these constraints, this example suggests that, in some cases, dynamic cellular constraints may impose previously unappreciated secondary constraints on the evolution of gene regulatory networks that favors heterogeneous expression.
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Affiliation(s)
| | | | - Blair W Perry
- Department of Biology, The University of Texas Arlington, Texas, USA
- School of Biological Sciences, Washington State University, Pullman, Washington, USA
| | - Richard H Adams
- Department of Entomology and Plant Pathology, University of Arkansas, Fayetteville, USA
| | - Anthony J Saviola
- Department of Biochemistry and Molecular Genetics, University of Colorado Denver, Aurora, USA
| | - Stephen P Mackessy
- School of Biological Sciences, University of Northern Colorado, Greeley, USA
| | - Todd A Castoe
- Department of Biology, The University of Texas Arlington, Texas, USA
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24
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Hara Y, Kuraku S. The impact of local genomic properties on the evolutionary fate of genes. eLife 2023; 12:82290. [PMID: 37223962 DOI: 10.7554/elife.82290] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Accepted: 04/25/2023] [Indexed: 05/25/2023] Open
Abstract
Functionally indispensable genes are likely to be retained and otherwise to be lost during evolution. This evolutionary fate of a gene can also be affected by factors independent of gene dispensability, including the mutability of genomic positions, but such features have not been examined well. To uncover the genomic features associated with gene loss, we investigated the characteristics of genomic regions where genes have been independently lost in multiple lineages. With a comprehensive scan of gene phylogenies of vertebrates with a careful inspection of evolutionary gene losses, we identified 813 human genes whose orthologs were lost in multiple mammalian lineages: designated 'elusive genes.' These elusive genes were located in genomic regions with rapid nucleotide substitution, high GC content, and high gene density. A comparison of the orthologous regions of such elusive genes across vertebrates revealed that these features had been established before the radiation of the extant vertebrates approximately 500 million years ago. The association of human elusive genes with transcriptomic and epigenomic characteristics illuminated that the genomic regions containing such genes were subject to repressive transcriptional regulation. Thus, the heterogeneous genomic features driving gene fates toward loss have been in place and may sometimes have relaxed the functional indispensability of such genes. This study sheds light on the complex interplay between gene function and local genomic properties in shaping gene evolution that has persisted since the vertebrate ancestor.
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Affiliation(s)
- Yuichiro Hara
- Research Center for Genome & Medical Sciences, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Shigehiro Kuraku
- Molecular Life History Laboratory, Department of Genomics and Evolutionary Biology, National Institute of Genetics, Mishima, Japan
- Department of Genetics, Sokendai (Graduate University for Advanced Studies), Mishima, Japan
- RIKEN Center for Biosystems Dynamics Research, Kobe, Japan
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25
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Webster TH, Vannan A, Pinto BJ, Denbrock G, Morales M, Dolby GA, Fiddes IT, DeNardo DF, Wilson MA. Incomplete dosage balance and dosage compensation in the ZZ/ZW Gila monster ( Heloderma suspectum) revealed by de novo genome assembly. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.04.26.538436. [PMID: 37163099 PMCID: PMC10168389 DOI: 10.1101/2023.04.26.538436] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Reptiles exhibit a variety of modes of sex determination, including both temperature-dependent and genetic mechanisms. Among those species with genetic sex determination, sex chromosomes of varying heterogamety (XX/XY and ZZ/ZW) have been observed with different degrees of differentiation. Karyotype studies have demonstrated that Gila monsters (Heloderma suspectum) have ZZ/ZW sex determination and this system is likely homologous to the ZZ/ZW system in the Komodo dragon (Varanus komodoensis), but little else is known about their sex chromosomes. Here, we report the assembly and analysis of the Gila monster genome. We generated a de novo draft genome assembly for a male using 10X Genomics technology. We further generated and analyzed short-read whole genome sequencing and whole transcriptome sequencing data for three males and three females. By comparing female and male genomic data, we identified four putative Z-chromosome scaffolds. These putative Z-chromosome scaffolds are homologous to Z-linked scaffolds identified in the Komodo dragon. Further, by analyzing RNAseq data, we observed evidence of incomplete dosage compensation between the Gila monster Z chromosome and autosomes and a lack of balance in Z-linked expression between the sexes. In particular, we observe lower expression of the Z in females (ZW) than males (ZZ) on a global basis, though we find evidence suggesting local gene-by-gene compensation. This pattern has been observed in most other ZZ/ZW systems studied to date and may represent a general pattern for female heterogamety in vertebrates.
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Affiliation(s)
- Timothy H. Webster
- Department of Anthropology, University of Utah, Salt Lake City, UT
- School of Life Sciences, Arizona State University, Tempe, AZ
| | - Annika Vannan
- School of Life Sciences, Arizona State University, Tempe, AZ
| | - Brendan J. Pinto
- School of Life Sciences, Arizona State University, Tempe, AZ
- Center for Evolution and Medicine, Arizona State University, Tempe, AZ
- Department of Zoology, Milwaukee Public Museum, Milwaukee, WI USA
| | - Grant Denbrock
- School of Life Sciences, Arizona State University, Tempe, AZ
| | - Matheo Morales
- School of Life Sciences, Arizona State University, Tempe, AZ
- Department of Genetics, Yale University, New Haven, CT
| | - Greer A. Dolby
- School of Life Sciences, Arizona State University, Tempe, AZ
- Center for Mechanisms of Evolution, Biodesign Institute, Tempe, AZ
| | | | - Dale F. DeNardo
- School of Life Sciences, Arizona State University, Tempe, AZ
| | - Melissa A. Wilson
- School of Life Sciences, Arizona State University, Tempe, AZ
- Center for Evolution and Medicine, Arizona State University, Tempe, AZ
- Center for Mechanisms of Evolution, Biodesign Institute, Tempe, AZ
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26
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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.
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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
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27
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Li W, Du J, Yang L, Liang Q, Yang M, Zhou X, Du W. Chromosome-level genome assembly and population genomics of Mongolian racerunner (Eremias argus) provide insights into high-altitude adaptation in lizards. BMC Biol 2023; 21:40. [PMID: 36803146 PMCID: PMC9942394 DOI: 10.1186/s12915-023-01535-z] [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: 01/22/2022] [Accepted: 02/03/2023] [Indexed: 02/22/2023] Open
Abstract
BACKGROUND Although the extreme environmental adaptation of organisms is a hot topic in evolutionary biology, genetic adaptation to high-altitude environment remains poorly characterized in ectothermic animals. Squamates are among the most diverse terrestrial vertebrates, with tremendous ecological plasticity and karyotype diversity, and are a unique model system to investigate the genetic footprints of adaptation. RESULTS We report the first chromosome-level assembly of the Mongolian racerunner (Eremias argus) and our comparative genomics analyses found that multiple chromosome fissions/fusions events are unique to lizards. We further sequenced the genomes of 61 Mongolian racerunner individuals that were collected from altitudes ranging from ~ 80 to ~ 2600 m above sea level (m.a.s.l.). Population genomic analyses revealed many novel genomic regions under strong selective sweeps in populations endemic to high altitudes. Genes embedded in those genomic regions are mainly associated with energy metabolism and DNA damage repair pathways. Moreover, we identified and validated two substitutions of PHF14 that may enhance the lizards' tolerance to hypoxia at high altitudes. CONCLUSIONS Our study reveals the molecular mechanism of high-altitude adaptation in ectothermic animal using lizard as a research subject and provides a high-quality lizard genomic resource for future research.
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Affiliation(s)
- Weiming Li
- grid.9227.e0000000119573309Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101 China ,grid.410726.60000 0004 1797 8419University of Chinese Academic of Sciences, Beijing, China
| | - Juan Du
- grid.9227.e0000000119573309Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101 China ,grid.410726.60000 0004 1797 8419University of Chinese Academic of Sciences, Beijing, China
| | - Lingyun Yang
- grid.410753.4Novogene Bioinformatics Institute, Beijing, 100083 China
| | - Qiqi Liang
- grid.410753.4Novogene Bioinformatics Institute, Beijing, 100083 China
| | - Mengyuan Yang
- grid.9227.e0000000119573309Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101 China ,grid.410726.60000 0004 1797 8419University of Chinese Academic of Sciences, Beijing, China
| | - Xuming Zhou
- Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China.
| | - Weiguo Du
- Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China. .,Center for Excellence in Animal Evolution and Genetics, Chinese Academy of Sciences, Kunming, 650223, China.
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28
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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.
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29
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A novel broad spectrum venom metalloproteinase autoinhibitor in the rattlesnake Crotalus atrox evolved via a shift in paralog function. Proc Natl Acad Sci U S A 2022; 119:e2214880119. [PMID: 36508672 PMCID: PMC9907073 DOI: 10.1073/pnas.2214880119] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The complexity of snake venom composition reflects adaptation to the diversity of prey and may be driven at times by a coevolutionary arms race between snakes and venom-resistant prey. However, many snakes are also resistant to their own venom due to serum-borne inhibitors of venom toxins, which raises the question of how snake autoinhibitors maintain their efficacy as venom proteins evolve. To investigate this potential three-way arms race among venom, prey, and autoinhibitors, we have identified and traced the evolutionary origin of serum inhibitors of snake venom metalloproteinases (SVMPs) in the Western Diamondback rattlesnake Crotalus atrox which possesses the largest known battery of SVMP genes among crotalids examined. We found that C. atrox expresses five members of a Fetuin A-related metalloproteinase inhibitor family but that one family member, FETUA-3, is the major SVMP inhibitor that binds to approximately 20 different C. atrox SVMPs and inhibits activities of all three SVMP classes. We show that the fetua-3 gene arose deep within crotalid evolution before the origin of New World species but, surprisingly, fetua-3 belongs to a different paralog group than previously identified SVMP inhibitors in Asian and South American crotalids. Conversely, the C. atrox FETUA-2 ortholog of previously characterized crotalid SVMP inhibitors shows limited activity against C. atrox SVMPs. These results reveal that there has been a functional evolutionary shift in the major SVMP inhibitor in the C. atrox lineage as the SVMP family expanded and diversified in the Crotalus lineage. This broad-spectrum inhibitor may be of potential therapeutic interest.
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30
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Cytogenetic Analysis of the Bimodal Karyotype of the Common European Adder, Vipera berus (Viperidae). Animals (Basel) 2022; 12:ani12243563. [PMID: 36552484 PMCID: PMC9774092 DOI: 10.3390/ani12243563] [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: 11/28/2022] [Revised: 12/12/2022] [Accepted: 12/15/2022] [Indexed: 12/23/2022] Open
Abstract
Vipera berus is the species with the largest range of snakes on Earth and one of the largest among reptiles in general. It is also the only snake species found in the Arctic Circle. Vipera berus is the most involved species of the genus Vipera in the process of interspecific hybridization in nature. The taxonomy of the genus Vipera is based on molecular markers and morphology and requires clarification using SC-karyotyping. This work is a detailed comparative study of the somatic and meiotic karyotypes of V. berus, with special attention to DNA and protein markers associated with synaptonemal complexes. The karyotype of V. berus is a remarkable example of a bimodal karyotype containing both 16 large macrochromosomes and 20 microchromosomes. We traced the stages of the asynchronous assembly of both types of bivalents. The number of crossing-over sites per pachytene nucleus, the localization of the nucleolar organizer, and the unique heterochromatin block on the autosomal bivalent 6-an important marker-were determined. Our results show that the average number of crossing-over sites per pachytene nucleus is 49.5, and the number of MLH1 sites per bivalent 1 reached 11, which is comparable to several species of agamas.
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Nikolakis ZL, Schield DR, Westfall AK, Perry BW, Ivey KN, Orton RW, Hales NR, Adams RH, Meik JM, Parker JM, Smith CF, Gompert Z, Mackessy SP, Castoe TA. Evidence that genomic incompatibilities and other multilocus processes impact hybrid fitness in a rattlesnake hybrid zone. Evolution 2022; 76:2513-2530. [PMID: 36111705 DOI: 10.1111/evo.14612] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2021] [Revised: 06/24/2022] [Accepted: 08/15/2022] [Indexed: 01/22/2023]
Abstract
Hybrid zones provide valuable opportunities to understand the genomic mechanisms that promote speciation by providing insight into factors involved in intermediate stages of speciation. Here, we investigate introgression in a hybrid zone between two rattlesnake species (Crotalus viridis and Crotalus oreganus concolor) that have undergone historical allopatric divergence and recent range expansion and secondary contact. We use Bayesian genomic cline models to characterize genomic patterns of introgression between these lineages and identify loci potentially subject to selection in hybrids. We find evidence for a large number of genomic regions with biased ancestry that deviate from the genomic background in hybrids (i.e., excess ancestry loci), which tend to be associated with genomic regions with higher recombination rates. We also identify suites of excess ancestry loci that show highly correlated allele frequencies (including conspecific and heterospecific combinations) across physically unlinked genomic regions in hybrids. Our findings provide evidence for multiple multilocus evolutionary processes impacting hybrid fitness in this system.
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Affiliation(s)
- Zachary L Nikolakis
- Department of Biology, University of Texas at Arlington, Arlington, Texas, 76019
| | - Drew R Schield
- Department of Biology, University of Texas at Arlington, Arlington, Texas, 76019.,Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, Colorado, 80309
| | - Aundrea K Westfall
- Department of Biology, University of Texas at Arlington, Arlington, Texas, 76019
| | - Blair W Perry
- Department of Biology, University of Texas at Arlington, Arlington, Texas, 76019
| | - Kathleen N Ivey
- Department of Biology, University of Texas at Arlington, Arlington, Texas, 76019
| | - Richard W Orton
- Department of Biology, University of Texas at Arlington, Arlington, Texas, 76019
| | - Nicole R Hales
- Department of Biology, University of Texas at Arlington, Arlington, Texas, 76019
| | - Richard H Adams
- Department of Biological and Environmental Sciences, Georgia College and State University, Milledgeville, Georgia, 31061
| | - Jesse M Meik
- Department of Biological Sciences, Tarleton State University, Stephenville, Texas, 76402
| | - Joshua M Parker
- Department of Life Sciences, Fresno City College, Fresno, California, 93741
| | - Cara F Smith
- School of Biological Sciences, University of Northern Colorado, Greeley, Colorado, 80639
| | | | - Stephen P Mackessy
- School of Biological Sciences, University of Northern Colorado, Greeley, Colorado, 80639
| | - Todd A Castoe
- Department of Biology, University of Texas at Arlington, Arlington, Texas, 76019
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32
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Genomic, transcriptomic, and epigenomic analysis of a medicinal snake, Bungarus multicinctus, to provides insights into the origin of Elapidae neurotoxins. Acta Pharm Sin B 2022; 13:2234-2249. [DOI: 10.1016/j.apsb.2022.11.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Revised: 10/20/2022] [Accepted: 11/11/2022] [Indexed: 11/19/2022] Open
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33
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Chromosome-scale genome assembly of the brown anole (Anolis sagrei), an emerging model species. Commun Biol 2022; 5:1126. [PMID: 36284162 PMCID: PMC9596491 DOI: 10.1038/s42003-022-04074-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2021] [Accepted: 10/06/2022] [Indexed: 12/12/2022] Open
Abstract
Rapid technological improvements are democratizing access to high quality, chromosome-scale genome assemblies. No longer the domain of only the most highly studied model organisms, now non-traditional and emerging model species can be genome-enabled using a combination of sequencing technologies and assembly software. Consequently, old ideas built on sparse sampling across the tree of life have recently been amended in the face of genomic data drawn from a growing number of high-quality reference genomes. Arguably the most valuable are those long-studied species for which much is already known about their biology; what many term emerging model species. Here, we report a highly complete chromosome-scale genome assembly for the brown anole, Anolis sagrei – a lizard species widely studied across a variety of disciplines and for which a high-quality reference genome was long overdue. This assembly exceeds the vast majority of existing reptile and snake genomes in contiguity (N50 = 253.6 Mb) and annotation completeness. Through the analysis of this genome and population resequence data, we examine the history of repetitive element accumulation, identify the X chromosome, and propose a hypothesis for the evolutionary history of fusions between autosomes and the X that led to the sex chromosomes of A. sagrei. A highly-complete chromosome-scale genome assembly of the brown anole, Anolis sagrei, provides insight into the evolution of sex chromosomes and is a crucial resource for this model lizard species.
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34
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Schield DR, Perry BW, Adams RH, Holding ML, Nikolakis ZL, Gopalan SS, Smith CF, Parker JM, Meik JM, DeGiorgio M, Mackessy SP, Castoe TA. The roles of balancing selection and recombination in the evolution of rattlesnake venom. Nat Ecol Evol 2022; 6:1367-1380. [PMID: 35851850 PMCID: PMC9888523 DOI: 10.1038/s41559-022-01829-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Accepted: 06/15/2022] [Indexed: 02/02/2023]
Abstract
The origin of snake venom involved duplication and recruitment of non-venom genes into venom systems. Several studies have predicted that directional positive selection has governed this process. Venom composition varies substantially across snake species and venom phenotypes are locally adapted to prey, leading to coevolutionary interactions between predator and prey. Venom origins and contemporary snake venom evolution may therefore be driven by fundamentally different selection regimes, yet investigations of population-level patterns of selection have been limited. Here, we use whole-genome data from 68 rattlesnakes to test hypotheses about the factors that drive genomic diversity and differentiation in major venom gene regions. We show that selection has resulted in long-term maintenance of genetic diversity within and between species in multiple venom gene families. Our findings are inconsistent with a dominant role of directional positive selection and instead support a role of long-term balancing selection in shaping venom evolution. We also detect rapid decay of linkage disequilibrium due to high recombination rates in venom regions, suggesting that venom genes have reduced selective interference with nearby loci, including other venom paralogues. Our results provide an example of long-term balancing selection that drives trans-species polymorphism and help to explain how snake venom keeps pace with prey resistance.
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Affiliation(s)
- Drew R Schield
- Department of Biology, University of Texas at Arlington, Arlington, TX, USA.
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, CO, USA.
| | - Blair W Perry
- Department of Biology, University of Texas at Arlington, Arlington, TX, USA
- School of Biological Sciences, Washington State University, Pullman, WA, USA
| | - Richard H Adams
- Department of Biological and Environmental Sciences, Georgia College and State University, Milledgeville, GA, USA
| | | | | | | | - Cara F Smith
- School of Biological Sciences, University of Northern Colorado, Greeley, CO, USA
| | - Joshua M Parker
- Life Science Department, Fresno City College, Fresno, CA, USA
| | - Jesse M Meik
- Department of Biological Sciences, Tarleton State University, Stephenville, TX, USA
| | - Michael DeGiorgio
- Department of Electrical Engineering and Computer Science, Florida Atlantic University, Boca Raton, FL, USA
| | - Stephen P Mackessy
- School of Biological Sciences, University of Northern Colorado, Greeley, CO, USA
| | - Todd A Castoe
- Department of Biology, University of Texas at Arlington, Arlington, TX, USA.
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35
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de Manuel M, Wu FL, Przeworski M. A paternal bias in germline mutation is widespread in amniotes and can arise independently of cell division numbers. eLife 2022; 11:e80008. [PMID: 35916372 PMCID: PMC9439683 DOI: 10.7554/elife.80008] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Accepted: 08/01/2022] [Indexed: 11/13/2022] Open
Abstract
In humans and other mammals, germline mutations are more likely to arise in fathers than in mothers. Although this sex bias has long been attributed to DNA replication errors in spermatogenesis, recent evidence from humans points to the importance of mutagenic processes that do not depend on cell division, calling into question our understanding of this basic phenomenon. Here, we infer the ratio of paternal-to-maternal mutations, α, in 42 species of amniotes, from putatively neutral substitution rates of sex chromosomes and autosomes. Despite marked differences in gametogenesis, physiologies and environments across species, fathers consistently contribute more mutations than mothers in all the species examined, including mammals, birds, and reptiles. In mammals, α is as high as 4 and correlates with generation times; in birds and snakes, α appears more stable around 2. These observations are consistent with a simple model, in which mutations accrue at equal rates in both sexes during early development and at a higher rate in the male germline after sexual differentiation, with a conserved paternal-to-maternal ratio across species. Thus, α may reflect the relative contributions of two or more developmental phases to total germline mutations, and is expected to depend on generation time even if mutations do not track cell divisions.
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Affiliation(s)
- Marc de Manuel
- Department of Biological Sciences, Columbia UniversityNew YorkUnited States
| | - Felix L Wu
- Department of Biological Sciences, Columbia UniversityNew YorkUnited States
| | - Molly Przeworski
- Department of Systems Biology, Columbia UniversityNew YorkUnited States
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36
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Schield DR, Perry BW, Card DC, Pasquesi GIM, Westfall AK, Mackessy SP, Castoe TA. The rattlesnake W chromosome: A GC-rich retroelement refugium with retained gene function across ancient evolutionary strata. Genome Biol Evol 2022; 14:6648526. [PMID: 35867356 PMCID: PMC9447483 DOI: 10.1093/gbe/evac116] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/17/2022] [Indexed: 11/18/2022] Open
Abstract
Sex chromosomes diverge after the establishment of recombination suppression, resulting in differential sex-linkage of genes involved in genetic sex determination and dimorphic traits. This process produces systems of male or female heterogamety wherein the Y and W chromosomes are only present in one sex and are often highly degenerated. Sex-limited Y and W chromosomes contain valuable information about the evolutionary transition from autosomes to sex chromosomes, yet detailed characterizations of the structure, composition, and gene content of sex-limited chromosomes are lacking for many species. In this study, we characterize the female-specific W chromosome of the prairie rattlesnake (Crotalus viridis) and evaluate how recombination suppression and other processes have shaped sex chromosome evolution in ZW snakes. Our analyses indicate that the rattlesnake W chromosome is over 80% repetitive and that an abundance of GC-rich mdg4 elements has driven an overall high degree of GC-richness despite a lack of recombination. The W chromosome is also highly enriched for repeat sequences derived from endogenous retroviruses and likely acts as a “refugium” for these and other retroelements. We annotated 219 putatively functional W-linked genes across at least two evolutionary strata identified based on estimates of sequence divergence between Z and W gametologs. The youngest of these strata is relatively gene-rich, however gene expression across strata suggests retained gene function amidst a greater degree of degeneration following ancient recombination suppression. Functional annotation of W-linked genes indicates a specialization of the W chromosome for reproductive and developmental function since recombination suppression from the Z chromosome.
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Affiliation(s)
- Drew R Schield
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, CO, USA
| | - Blair W Perry
- Department of Biology, University of Texas at Arlington, Arlington, TX, USA.,School of Biological Sciences, Washington State University, Pullman, WA, USA
| | - Daren C Card
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, USA.,Museum of Comparative Zoology, Harvard University, Cambridge, MA, USA
| | - Giulia I M Pasquesi
- Department of Molecular, Cellular, and Developmental Biology, University of Colorado, Boulder, CO, USA
| | - Aundrea K Westfall
- Department of Biology, University of Texas at Arlington, Arlington, TX, USA
| | - Stephen P Mackessy
- School of Biological Sciences, University of Northern Colorado, Greeley, CO, USA
| | - Todd A Castoe
- Department of Biology, University of Texas at Arlington, Arlington, TX, USA
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37
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Zhang ZY, Lv Y, Wu W, Yan C, Tang CY, Peng C, Li JT. The structural and functional divergence of a neglected three-finger toxin subfamily in lethal elapids. Cell Rep 2022; 40:111079. [PMID: 35830808 DOI: 10.1016/j.celrep.2022.111079] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2022] [Revised: 05/04/2022] [Accepted: 06/20/2022] [Indexed: 11/24/2022] Open
Abstract
Bungarus multicinctus is a widely distributed and medically important elapid snake that produces lethal neurotoxic venom. To study and enhance existing antivenom, we explore the complete repertoire of its toxin genes based on de novo chromosome-level assembly and multi-tissue transcriptome data. Comparative genomic analyses suggest that the three-finger toxin family (3FTX) may evolve through the neofunctionalization of flanking LY6E. A long-neglected 3FTX subfamily (i.e., MKA-3FTX) is also investigated. Only one MKA-3FTX gene, which evolves a different protein conformation, is under positive selection and actively transcribed in the venom gland, functioning as a major toxin effector together with MKT-3FTX subfamily homologs. Furthermore, this lethal snake may acquire self-resistance to its β-bungarotoxin via amino acid replacements on fast-evolving KCNA2. This study provides valuable resources for further evolutionary and structure-function studies of snake toxins, which are fundamental for the development of effective antivenoms and drug candidates.
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Affiliation(s)
- Zhi-Yi Zhang
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization & Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, Sichuan 610041, China
| | - Yunyun Lv
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization & Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, Sichuan 610041, China; College of Life Science, Neijiang Normal University, Neijiang, Sichuan 641100, China
| | - Wei Wu
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization & Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, Sichuan 610041, China; University of Chinese Academy of Sciences, Beijing 101408, China
| | - Chaochao Yan
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization & Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, Sichuan 610041, China
| | - Chen-Yang Tang
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization & Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, Sichuan 610041, China
| | - Changjun Peng
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization & Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, Sichuan 610041, China; University of Chinese Academy of Sciences, Beijing 101408, China
| | - Jia-Tang Li
- CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization & Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, Sichuan 610041, China; University of Chinese Academy of Sciences, Beijing 101408, China; Center for Excellence in Animal Evolution and Genetics, Chinese Academy of Sciences, Kunming, Yunnan 650223, China.
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38
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Gopalan SS, Perry BW, Schield DR, Smith CF, Mackessy SP, Castoe TA. Origins, genomic structure and copy number variation of snake venom myotoxins. Toxicon 2022; 216:92-106. [PMID: 35820472 DOI: 10.1016/j.toxicon.2022.06.014] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Revised: 06/21/2022] [Accepted: 06/27/2022] [Indexed: 10/17/2022]
Abstract
Crotamine, myotoxin a and homologs are short peptides that often comprise major fractions of rattlesnake venoms and have been extensively studied for their bioactive properties. These toxins are thought to be important for rapidly immobilizing mammalian prey and are implicated in serious, and sometimes fatal, responses to envenomation in humans. While high quality reference genomes for multiple venomous snakes are available, the loci that encode myotoxins have not been successfully assembled in any existing genome assembly. Here, we integrate new and existing genomic and transcriptomic data from the Prairie Rattlesnake (Crotalus viridis viridis) to reconstruct, characterize, and infer the chromosomal locations of myotoxin-encoding loci. We integrate long-read transcriptomics (Pacific Bioscience's Iso-Seq) and short-read RNA-seq to infer gene sequence diversity and characterize patterns of myotoxin and paralogous β-defensin expression across multiple tissues. We also identify two long non-coding RNA sequences which both encode functional myotoxins, demonstrating a newly discovered source of venom coding sequence diversity. We also integrate long-range mate-pair chromatin contact data and linked-read sequencing to infer the structure and chromosomal locations of the three myotoxin-like loci. Further, we conclude that the venom-associated myotoxin is located on chromosome 1 and is adjacent to non-venom paralogs. Consistent with this locus contributing to venom composition, we find evidence that the promoter of this gene is selectively open in venom gland tissue and contains transcription factor binding sites implicated in broad trans-regulatory pathways that regulate snake venoms. This study provides the best genomic reconstruction of myotoxin loci to date and raises questions about the physiological roles and interplay between myotoxin and related genes, as well as the genomic origins of snake venom variation.
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Affiliation(s)
- Siddharth S Gopalan
- Department of Biology, 501 S. Nedderman Dr., The University of Texas Arlington, Arlington, TX, 76019, USA
| | - Blair W Perry
- Department of Biology, 501 S. Nedderman Dr., The University of Texas Arlington, Arlington, TX, 76019, USA; School of Biological Sciences, Washington State University, Pullman, WA, 99164, USA
| | - Drew R Schield
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, CO, 80309, USA
| | - Cara F Smith
- School of Biological Sciences, 501 20th Street, University of Northern Colorado, Greeley, CO, 80639, USA; Department of Biochemistry and Molecular Biology, 12801 East 17th Avenue, University of Colorado Denver, Aurora, CO, 80045, USA
| | - Stephen P Mackessy
- School of Biological Sciences, 501 20th Street, University of Northern Colorado, Greeley, CO, 80639, USA
| | - Todd A Castoe
- Department of Biology, 501 S. Nedderman Dr., The University of Texas Arlington, Arlington, TX, 76019, USA.
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39
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Myers EA, Strickland JL, Rautsaw RM, Mason AJ, Schramer TD, Nystrom GS, Hogan MP, Yooseph S, Rokyta DR, Parkinson CL. De Novo Genome Assembly Highlights the Role of Lineage-Specific Duplications in the Evolution of Venom in Fea’s Viper. Genome Biol Evol 2022; 14:6603630. [PMID: 35670514 PMCID: PMC9256536 DOI: 10.1093/gbe/evac082] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/25/2022] [Indexed: 11/12/2022] Open
Abstract
Despite the medical significance to humans and important ecological roles filled by vipers, few high-quality genomic resources exist for these snakes outside of a few genera of pitvipers. Here we sequence, assemble, and annotate the genome of Fea’s Viper (Azemiops feae). This taxon is distributed in East Asia and belongs to a monotypic subfamily, sister to the pitvipers. The newly sequenced genome resulted in a 1.56 Gb assembly, a contig N50 of 1.59 Mb, with 97.6% of the genome assembly in contigs >50 Kb, and a BUSCO completeness of 92.4%. We found that A. feae venom is primarily composed of phospholipase A2 (PLA2) proteins expressed by genes that likely arose from lineage-specific PLA2 gene duplications. Additionally, we show that renin, an enzyme associated with blood pressure regulation in mammals and known from the venoms of two viper species including A. feae, is expressed in the venom gland at comparative levels to known toxins and is present in the venom proteome. The cooption of this gene as a toxin may be more widespread in viperids than currently known. To investigate the historical population demographics of A. feae, we performed coalescent-based analyses and determined that the effective population size has remained stable over the last 100 kyr. This suggests Quaternary glacial cycles likely had minimal influence on the demographic history of A. feae. This newly assembled genome will be an important resource for studying the genomic basis of phenotypic evolution and understanding the diversification of venom toxin gene families.
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Affiliation(s)
- Edward A. Myers
- Department of Biological Sciences, Clemson University , Clemson, SC 29634, USA
| | - Jason L. Strickland
- Department of Biological Sciences, Clemson University , Clemson, SC 29634, USA
- Department of Biology, University of South Alabama , Mobile, AL 36688, USA
| | - Rhett M. Rautsaw
- Department of Biological Sciences, Clemson University , Clemson, SC 29634, USA
| | - Andrew J. Mason
- Department of Biological Sciences, Clemson University , Clemson, SC 29634, USA
- Department of Evolution, Ecology and Organismal Biology, The Ohio State University , Columbus, OH 43210, USA
| | - Tristan D. Schramer
- Department of Biological Sciences, Clemson University , Clemson, SC 29634, USA
| | - Gunnar S. Nystrom
- Department of Biological Science, Florida State University , Tallahassee, FL 32306, USA
| | - Michael P. Hogan
- Department of Biological Science, Florida State University , Tallahassee, FL 32306, USA
| | - Shibu Yooseph
- Department of Computer Science, Genomics and Bioinformatics Cluster, University of Central Florida, 4000 Central Florida Blvd , Orlando, FL, 32816, USA
| | - Darin R. Rokyta
- Department of Biological Science, Florida State University , Tallahassee, FL 32306, USA
| | - Christopher L. Parkinson
- Department of Biological Sciences, Clemson University , Clemson, SC 29634, USA
- Department of Forestry and Environmental Conservation, Clemson University , Clemson, SC 29634, USA
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40
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Perry BW, Gopalan SS, Pasquesi GIM, Schield DR, Westfall AK, Smith CF, Koludarov I, Chippindale PT, Pellegrino MW, Chuong EB, Mackessy SP, Castoe TA. Snake venom gene expression is coordinated by novel regulatory architecture and the integration of multiple co-opted vertebrate pathways. Genome Res 2022; 32:1058-1073. [PMID: 35649579 PMCID: PMC9248877 DOI: 10.1101/gr.276251.121] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Accepted: 04/11/2022] [Indexed: 11/25/2022]
Abstract
Understanding how regulatory mechanisms evolve is critical for understanding the processes that give rise to novel phenotypes. Snake venom systems represent a valuable and tractable model for testing hypotheses related to the evolution of novel regulatory networks, yet the regulatory mechanisms underlying venom production remain poorly understood. Here, we use functional genomics approaches to investigate venom regulatory architecture in the prairie rattlesnake and identify cis-regulatory sequences (enhancers and promoters), trans-regulatory transcription factors, and integrated signaling cascades involved in the regulation of snake venom genes. We find evidence that two conserved vertebrate pathways, the extracellular signal-regulated kinase and unfolded protein response pathways, were co-opted to regulate snake venom. In one large venom gene family (snake venom serine proteases), this co-option was likely facilitated by the activity of transposable elements. Patterns of snake venom gene enhancer conservation, in some cases spanning 50 million yr of lineage divergence, highlight early origins and subsequent lineage-specific adaptations that have accompanied the evolution of venom regulatory architecture. We also identify features of chromatin structure involved in venom regulation, including topologically associated domains and CTCF loops that underscore the potential importance of novel chromatin structure to coevolve when duplicated genes evolve new regulatory control. Our findings provide a model for understanding how novel regulatory systems may evolve through a combination of genomic processes, including tandem duplication of genes and regulatory sequences, cis-regulatory sequence seeding by transposable elements, and diverse transcriptional regulatory proteins controlled by a co-opted regulatory cascade.
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Affiliation(s)
- Blair W Perry
- Department of Biology, University of Texas at Arlington, Arlington, Texas 76019, USA
- School of Biological Sciences, Washington State University, Pullman, Washington 99164, USA
| | - Siddharth S Gopalan
- Department of Biology, University of Texas at Arlington, Arlington, Texas 76019, USA
| | - Giulia I M Pasquesi
- Department of Molecular, Cellular, and Developmental Biology, University of Colorado, Boulder, Colorado 80309, USA
| | - Drew R Schield
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, Colorado 80309, USA
| | - Aundrea K Westfall
- Department of Biology, University of Texas at Arlington, Arlington, Texas 76019, USA
| | - Cara F Smith
- School of Biological Sciences, University of Northern Colorado, Greeley, Colorado 80639, USA
| | - Ivan Koludarov
- Animal Venomics Group, Justus Liebig University, Giessen, 35390, Germany
| | - Paul T Chippindale
- Department of Biology, University of Texas at Arlington, Arlington, Texas 76019, USA
| | - Mark W Pellegrino
- Department of Biology, University of Texas at Arlington, Arlington, Texas 76019, USA
| | - Edward B Chuong
- Department of Molecular, Cellular, and Developmental Biology, University of Colorado, Boulder, Colorado 80309, USA
| | - Stephen P Mackessy
- School of Biological Sciences, University of Northern Colorado, Greeley, Colorado 80639, USA
| | - Todd A Castoe
- Department of Biology, University of Texas at Arlington, Arlington, Texas 76019, USA
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41
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von Reumont BM, Anderluh G, Antunes A, Ayvazyan N, Beis D, Caliskan F, Crnković A, Damm M, Dutertre S, Ellgaard L, Gajski G, German H, Halassy B, Hempel BF, Hucho T, Igci N, Ikonomopoulou MP, Karbat I, Klapa MI, Koludarov I, Kool J, Lüddecke T, Ben Mansour R, Vittoria Modica M, Moran Y, Nalbantsoy A, Ibáñez MEP, Panagiotopoulos A, Reuveny E, Céspedes JS, Sombke A, Surm JM, Undheim EAB, Verdes A, Zancolli G. Modern venomics-Current insights, novel methods, and future perspectives in biological and applied animal venom research. Gigascience 2022; 11:giac048. [PMID: 35640874 PMCID: PMC9155608 DOI: 10.1093/gigascience/giac048] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2022] [Revised: 04/10/2022] [Accepted: 04/12/2022] [Indexed: 12/11/2022] Open
Abstract
Venoms have evolved >100 times in all major animal groups, and their components, known as toxins, have been fine-tuned over millions of years into highly effective biochemical weapons. There are many outstanding questions on the evolution of toxin arsenals, such as how venom genes originate, how venom contributes to the fitness of venomous species, and which modifications at the genomic, transcriptomic, and protein level drive their evolution. These questions have received particularly little attention outside of snakes, cone snails, spiders, and scorpions. Venom compounds have further become a source of inspiration for translational research using their diverse bioactivities for various applications. We highlight here recent advances and new strategies in modern venomics and discuss how recent technological innovations and multi-omic methods dramatically improve research on venomous animals. The study of genomes and their modifications through CRISPR and knockdown technologies will increase our understanding of how toxins evolve and which functions they have in the different ontogenetic stages during the development of venomous animals. Mass spectrometry imaging combined with spatial transcriptomics, in situ hybridization techniques, and modern computer tomography gives us further insights into the spatial distribution of toxins in the venom system and the function of the venom apparatus. All these evolutionary and biological insights contribute to more efficiently identify venom compounds, which can then be synthesized or produced in adapted expression systems to test their bioactivity. Finally, we critically discuss recent agrochemical, pharmaceutical, therapeutic, and diagnostic (so-called translational) aspects of venoms from which humans benefit.
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Affiliation(s)
- Bjoern M von Reumont
- Goethe University Frankfurt, Institute for Cell Biology and Neuroscience, Department for Applied Bioinformatics, 60438 Frankfurt am Main, Germany
- LOEWE Centre for Translational Biodiversity Genomics, Senckenberg Frankfurt, Senckenberganlage 25, 60235 Frankfurt, Germany
- Justus Liebig University Giessen, Institute for Insectbiotechnology, Heinrich Buff Ring 26-32, 35396 Giessen, Germany
| | - Gregor Anderluh
- Department of Molecular Biology and Nanobiotechnology, National Institute of Chemistry, 1000 Ljubljana, Slovenia
| | - Agostinho Antunes
- CIIMAR/CIMAR, Interdisciplinary Centre of Marine and Environmental Research, University of Porto, Terminal de Cruzeiros do Porto de Leixões, Av. General Norton de Matos, s/n, 4450–208 Porto, Portugal
- Department of Biology, Faculty of Sciences, University of Porto, Rua do Campo Alegre, 4169-007 Porto, Portugal
| | - Naira Ayvazyan
- Orbeli Institute of Physiology of NAS RA, Orbeli ave. 22, 0028 Yerevan, Armenia
| | - Dimitris Beis
- Developmental Biology, Centre for Clinical, Experimental Surgery and Translational Research, Biomedical Research Foundation Academy of Athens, Athens 11527, Greece
| | - Figen Caliskan
- Department of Biology, Faculty of Science and Letters, Eskisehir Osmangazi University, TR-26040 Eskisehir, Turkey
| | - Ana Crnković
- Department of Molecular Biology and Nanobiotechnology, National Institute of Chemistry, 1000 Ljubljana, Slovenia
| | - Maik Damm
- Technische Universität Berlin, Department of Chemistry, Straße des 17. Juni 135, 10623 Berlin, Germany
| | | | - Lars Ellgaard
- Department of Biology, University of Copenhagen, DK-2200 Copenhagen, Denmark
| | - Goran Gajski
- Institute for Medical Research and Occupational Health, Mutagenesis Unit, Ksaverska cesta 2, 10000 Zagreb, Croatia
| | - Hannah German
- Amsterdam Institute of Molecular and Life Sciences, Division of BioAnalytical Chemistry, Faculty of Science, Vrije Universiteit Amsterdam, De Boelelaan 1085, 1081HV Amsterdam, The Netherlands
| | - Beata Halassy
- University of Zagreb, Centre for Research and Knowledge Transfer in Biotechnology, Trg Republike Hrvatske 14, 10000 Zagreb, Croatia
| | - Benjamin-Florian Hempel
- BIH Center for Regenerative Therapies BCRT, Charité - Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, Germany
| | - Tim Hucho
- Translational Pain Research, Department of Anesthesiology and Intensive Care Medicine, Faculty of Medicine and University Hospital Cologne, University of Cologne, 50931 Cologne, Germany
| | - Nasit Igci
- Nevsehir Haci Bektas Veli University, Faculty of Arts and Sciences, Department of Molecular Biology and Genetics, 50300 Nevsehir, Turkey
| | - Maria P Ikonomopoulou
- Madrid Institute for Advanced Studies in Food, Madrid,E28049, Spain
- The University of Queensland, St Lucia, QLD 4072, Australia
| | - Izhar Karbat
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Maria I Klapa
- Metabolic Engineering and Systems Biology Laboratory, Institute of Chemical Engineering Sciences, Foundation for Research & Technology Hellas (FORTH/ICE-HT), Patras GR-26504, Greece
| | - Ivan Koludarov
- Justus Liebig University Giessen, Institute for Insectbiotechnology, Heinrich Buff Ring 26-32, 35396 Giessen, Germany
| | - Jeroen Kool
- Amsterdam Institute of Molecular and Life Sciences, Division of BioAnalytical Chemistry, Faculty of Science, Vrije Universiteit Amsterdam, De Boelelaan 1085, 1081HV Amsterdam, The Netherlands
| | - Tim Lüddecke
- LOEWE Centre for Translational Biodiversity Genomics, Senckenberg Frankfurt, Senckenberganlage 25, 60235 Frankfurt, Germany
- Department of Bioresources, Fraunhofer Institute for Molecular Biology and Applied Ecology, 35392 Gießen, Germany
| | - Riadh Ben Mansour
- Department of Life Sciences, Faculty of Sciences, Gafsa University, Campus Universitaire Siidi Ahmed Zarrouk, 2112 Gafsa, Tunisia
| | - Maria Vittoria Modica
- Dept. of Biology and Evolution of Marine Organisms (BEOM), Stazione Zoologica Anton Dohrn, Via Po 25c, I-00198 Roma, Italy
| | - Yehu Moran
- Department of Ecology, Evolution and Behavior, Alexander Silberman Institute of Life Sciences, Faculty of Science, The Hebrew University of Jerusalem, Jerusalem 9190401, Israel
| | - Ayse Nalbantsoy
- Department of Bioengineering, Faculty of Engineering, Ege University, 35100 Bornova, Izmir, Turkey
| | - María Eugenia Pachón Ibáñez
- Unit of Infectious Diseases, Microbiology, and Preventive Medicine, Virgen del Rocío University Hospital, Institute of Biomedicine of Seville, 41013 Sevilla, Spain
- CIBER de Enfermedades Infecciosas, Instituto de Salud Carlos III, Madrid, Spain
| | - Alexios Panagiotopoulos
- Metabolic Engineering and Systems Biology Laboratory, Institute of Chemical Engineering Sciences, Foundation for Research & Technology Hellas (FORTH/ICE-HT), Patras GR-26504, Greece
- Animal Biology Division, Department of Biology, University of Patras, Patras, GR-26500, Greece
| | - Eitan Reuveny
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Javier Sánchez Céspedes
- Unit of Infectious Diseases, Microbiology, and Preventive Medicine, Virgen del Rocío University Hospital, Institute of Biomedicine of Seville, 41013 Sevilla, Spain
- CIBER de Enfermedades Infecciosas, Instituto de Salud Carlos III, Madrid, Spain
| | - Andy Sombke
- Department of Evolutionary Biology, University of Vienna, Djerassiplatz 1, 1030 Vienna, Austria
| | - Joachim M Surm
- Department of Ecology, Evolution and Behavior, Alexander Silberman Institute of Life Sciences, Faculty of Science, The Hebrew University of Jerusalem, Jerusalem 9190401, Israel
| | - Eivind A B Undheim
- University of Oslo, Centre for Ecological and Evolutionary Synthesis, Postboks 1066 Blindern 0316 Oslo, Norway
| | - Aida Verdes
- Department of Biodiversity and Evolutionary Biology, Museo Nacional de Ciencias Naturales, José Gutiérrez Abascal 2, 28006 Madrid, Spain
| | - Giulia Zancolli
- Department of Ecology and Evolution, University of Lausanne, 1015 Lausanne, Switzerland
- Swiss Institute of Bioinformatics, 1015 Lausanne, Switzerland
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42
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Mason AJ, Holding ML, Rautsaw RM, Rokyta DR, Parkinson CL, Gibbs HL. Venom gene sequence diversity and expression jointly shape diet adaptation in pitvipers. Mol Biol Evol 2022; 39:6567549. [PMID: 35413123 PMCID: PMC9040050 DOI: 10.1093/molbev/msac082] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Understanding the joint roles of protein sequence variation and differential expression during adaptive evolution is a fundamental, yet largely unrealized goal of evolutionary biology. Here, we use phylogenetic path analysis to analyze a comprehensive venom-gland transcriptome dataset spanning three genera of pitvipers to identify the functional genetic basis of a key adaptation (venom complexity) linked to diet breadth (DB). The analysis of gene-family-specific patterns reveals that, for genes encoding two of the most important venom proteins (snake venom metalloproteases and snake venom serine proteases), there are direct, positive relationships between sequence diversity (SD), expression diversity (ED), and increased DB. Further analysis of gene-family diversification for these proteins showed no constraint on how individual lineages achieved toxin gene SD in terms of the patterns of paralog diversification. In contrast, another major venom protein family (PLA2s) showed no relationship between venom molecular diversity and DB. Additional analyses suggest that other molecular mechanisms—such as higher absolute levels of expression—are responsible for diet adaptation involving these venom proteins. Broadly, our findings argue that functional diversity generated through sequence and expression variations jointly determine adaptation in the key components of pitviper venoms, which mediate complex molecular interactions between the snakes and their prey.
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Affiliation(s)
- Andrew J Mason
- Department of Evolution, Ecology and Organismal Biology, The Ohio State University, Columbus, OH, USA
| | | | - Rhett M Rautsaw
- Department of Biological Sciences, Clemson University, Clemson, SC, USA
| | - Darin R Rokyta
- Department of Biological Science, Florida State University, Tallahassee, FL, USA
| | - Christopher L Parkinson
- Department of Biological Sciences, Clemson University, Clemson, SC, USA.,Department of Forestry and Environmental Conservation, Clemson University, Clemson, SC, USA
| | - H Lisle Gibbs
- Department of Evolution, Ecology and Organismal Biology, The Ohio State University, Columbus, OH, USA
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43
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Pinto BJ, Keating SE, Nielsen SV, Scantlebury DP, Daza JD, Gamble T. Chromosome-Level Genome Assembly Reveals Dynamic Sex Chromosomes in Neotropical Leaf-Litter Geckos (Sphaerodactylidae: Sphaerodactylus). J Hered 2022; 113:272-287. [PMID: 35363859 PMCID: PMC9270867 DOI: 10.1093/jhered/esac016] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Accepted: 03/24/2022] [Indexed: 02/07/2023] Open
Abstract
Sex determination is a critical element of successful vertebrate development, suggesting that sex chromosome systems might be evolutionarily stable across lineages. For example, mammals and birds have maintained conserved sex chromosome systems over long evolutionary time periods. Other vertebrates, in contrast, have undergone frequent sex chromosome transitions, which is even more amazing considering we still know comparatively little across large swaths of their respective phylogenies. One reptile group in particular, the gecko lizards (infraorder Gekkota), shows an exceptional lability with regard to sex chromosome transitions and may possess the majority of transitions within squamates (lizards and snakes). However, detailed genomic and cytogenetic information about sex chromosomes is lacking for most gecko species, leaving large gaps in our understanding of the evolutionary processes at play. To address this, we assembled a chromosome-level genome for a gecko (Sphaerodactylidae: Sphaerodactylus) and used this assembly to search for sex chromosomes among six closely related species using a variety of genomic data, including whole-genome re-sequencing, RADseq, and RNAseq. Previous work has identified XY systems in two species of Sphaerodactylus geckos. We expand upon that work to identify between two and four sex chromosome cis-transitions (XY to a new XY) within the genus. Interestingly, we confirmed two different linkage groups as XY sex chromosome systems that were previously unknown to act as sex chromosomes in tetrapods (syntenic with Gallus chromosome 3 and Gallus chromosomes 18/30/33), further highlighting a unique and fascinating trend that most linkage groups have the potential to act as sex chromosomes in squamates.
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Affiliation(s)
- Brendan J Pinto
- Address correspondence to B. J. Pinto at the address above, or e-mail:
| | - Shannon E Keating
- Department of Biological Sciences, Marquette University, Milwaukee, WI 53233, USA
| | - Stuart V Nielsen
- Department of Biological Sciences, Louisiana State University in Shreveport, Shreveport, LA 71115, USA,Division of Herpetology, Florida Museum of Natural History, Gainesville, FL 32611, USA
| | | | - Juan D Daza
- Department of Biological Sciences, Sam Houston State University, Huntsville, TX 77340, USA
| | - Tony Gamble
- Milwaukee Public Museum, Milwaukee, WI 53233, USA,Department of Biological Sciences, Marquette University, Milwaukee, WI 53233, USA,Bell Museum of Natural History, University of Minnesota, St Paul, MN 55455, USA
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44
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Rao WQ, Kalogeropoulos K, Allentoft ME, Gopalakrishnan S, Zhao WN, Workman CT, Knudsen C, Jiménez-Mena B, Seneci L, Mousavi-Derazmahalleh M, Jenkins TP, Rivera-de-Torre E, Liu SQ, Laustsen AH. The rise of genomics in snake venom research: recent advances and future perspectives. Gigascience 2022; 11:giac024. [PMID: 35365832 PMCID: PMC8975721 DOI: 10.1093/gigascience/giac024] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Revised: 02/12/2022] [Accepted: 02/13/2022] [Indexed: 12/12/2022] Open
Abstract
Snake venoms represent a danger to human health, but also a gold mine of bioactive proteins that can be harnessed for drug discovery purposes. The evolution of snakes and their venom has been studied for decades, particularly via traditional morphological and basic genetic methods alongside venom proteomics. However, while the field of genomics has matured rapidly over the past 2 decades, owing to the development of next-generation sequencing technologies, snake genomics remains in its infancy. Here, we provide an overview of the state of the art in snake genomics and discuss its potential implications for studying venom evolution and toxinology. On the basis of current knowledge, gene duplication and positive selection are key mechanisms in the neofunctionalization of snake venom proteins. This makes snake venoms important evolutionary drivers that explain the remarkable venom diversification and adaptive variation observed in these reptiles. Gene duplication and neofunctionalization have also generated a large number of repeat sequences in snake genomes that pose a significant challenge to DNA sequencing, resulting in the need for substantial computational resources and longer sequencing read length for high-quality genome assembly. Fortunately, owing to constantly improving sequencing technologies and computational tools, we are now able to explore the molecular mechanisms of snake venom evolution in unprecedented detail. Such novel insights have the potential to affect the design and development of antivenoms and possibly other drugs, as well as provide new fundamental knowledge on snake biology and evolution.
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Affiliation(s)
- Wei-qiao Rao
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Søltofts Plads 224, 2800 Kongens Lyngby, Denmark
- Department of Mass Spectrometry, Beijing Genomics Institute-Research, 518083, Shenzhen, China
| | - Konstantinos Kalogeropoulos
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Søltofts Plads 224, 2800 Kongens Lyngby, Denmark
| | - Morten E Allentoft
- Trace and Environmental DNA (TrEnD) Laboratory, School of Molecular and Life Sciences, Curtin University, Kent Street, 6102, Bentley Perth, Australia
- Globe Institute, University of Copenhagen, Øster Voldgade 5, 1350, Copenhagen, Denmark
| | - Shyam Gopalakrishnan
- Globe Institute, University of Copenhagen, Øster Voldgade 5, 1350, Copenhagen, Denmark
| | - Wei-ning Zhao
- Department of Mass Spectrometry, Beijing Genomics Institute-Research, 518083, Shenzhen, China
| | - Christopher T Workman
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Søltofts Plads 224, 2800 Kongens Lyngby, Denmark
| | - Cecilie Knudsen
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Søltofts Plads 224, 2800 Kongens Lyngby, Denmark
| | - Belén Jiménez-Mena
- DTU Aqua, Technical University of Denmark, Vejlsøvej 39, 8600, Silkeborg, Denmark
| | - Lorenzo Seneci
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Søltofts Plads 224, 2800 Kongens Lyngby, Denmark
| | - Mahsa Mousavi-Derazmahalleh
- Trace and Environmental DNA (TrEnD) Laboratory, School of Molecular and Life Sciences, Curtin University, Kent Street, 6102, Bentley Perth, Australia
| | - Timothy P Jenkins
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Søltofts Plads 224, 2800 Kongens Lyngby, Denmark
| | - Esperanza Rivera-de-Torre
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Søltofts Plads 224, 2800 Kongens Lyngby, Denmark
| | - Si-qi Liu
- Department of Mass Spectrometry, Beijing Genomics Institute-Research, 518083, Shenzhen, China
| | - Andreas H Laustsen
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Søltofts Plads 224, 2800 Kongens Lyngby, Denmark
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Abstract
The venom glands of reptiles, particularly those of front-fanged advanced snakes, must satisfy conflicting biological demands: rapid synthesis of potentially labile and highly toxic proteins, storage in the gland lumen for long periods, stabilization of the stored secretions, immediate activation of toxins upon deployment and protection of the animal from the toxic effects of its own venom. This dynamic system could serve as a model for the study of a variety of different phenomena involving exocrine gland activation, protein synthesis, stabilization of protein products and secretory mechanisms. However, these studies have been hampered by a lack of a long-term model that can be propagated in the lab (as opposed to whole-animal studies). Numerous attempts have been made to extend the lifetime of venom gland secretory cells, but only recently has an organoid model been shown to have the requisite qualities of recapitulation of the native system, self-propagation and long-term viability (>1 year). A tractable model is now available for myriad cell- and molecular-level studies of venom glands, protein synthesis and secretion. However, venom glands of reptiles are not identical, and many differ very extensively in overall architecture, microanatomy and protein products produced. This Review summarizes the similarities among and differences between venom glands of helodermatid lizards and of rear-fanged and front-fanged snakes, highlighting those areas that are well understood and identifying areas where future studies can fill in significant gaps in knowledge of these ancient, yet fascinating systems.
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Affiliation(s)
- Stephen P Mackessy
- School of Biological Sciences, University of Northern Colorado, 501 20th St., CB 92, Greeley, CO 80639-0017, USA
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46
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Differences in PLA2 Constitution Distinguish the Venom of Two Endemic Brazilian Mountain Lanceheads, Bothrops cotiara and Bothrops fonsecai. Toxins (Basel) 2022; 14:toxins14040237. [PMID: 35448846 PMCID: PMC9028134 DOI: 10.3390/toxins14040237] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Revised: 02/15/2022] [Accepted: 02/23/2022] [Indexed: 02/01/2023] Open
Abstract
Interspecific differences in snake venom compositions can result from distinct regulatory mechanisms acting in each species. However, comparative analyses focusing on identifying regulatory elements and patterns that led to distinct venom composition are still scarce. Among venomous snakes, Bothrops cotiara and Bothrops fonsecai represent ideal models to complement our understanding of the regulatory mechanisms of venom production. These recently diverged species share a similar specialized diet, habitat, and natural history, but each presents a distinct venom phenotype. Here, we integrated data from the venom gland transcriptome and miRNome and the venom proteome of B. fonsecai and B. cotiara to better understand the regulatory mechanisms that may be acting to produce differing venom compositions. We detected not only the presence of similar toxin isoforms in both species but also distinct expression profiles of phospholipases A2 (PLA2) and some snake venom metalloproteinases (SVMPs) and snake venom serine proteinases (SVSPs) isoforms. We found evidence of modular expression regulation of several toxin isoforms implicated in venom divergence and observed correlated expression of several transcription factors. We did not find strong evidence for miRNAs shaping interspecific divergence of the venom phenotypes, but we identified a subset of toxin isoforms whose final expression may be fine-tuned by specific miRNAs. Sequence analysis on orthologous toxins showed a high rate of substitutions between PLA2s, which indicates that these toxins may be under strong positive selection or represent paralogous toxins in these species. Our results support other recent studies in suggesting that gene regulation is a principal mode of venom evolution across recent timescales, especially among species with conserved ecotypes.
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47
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Alfieri JM, Wang G, Jonika MM, Gill CA, Blackmon H, Athrey GN. A Primer for Single-Cell Sequencing in Non-Model Organisms. Genes (Basel) 2022; 13:380. [PMID: 35205423 PMCID: PMC8872538 DOI: 10.3390/genes13020380] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2022] [Revised: 02/12/2022] [Accepted: 02/17/2022] [Indexed: 02/05/2023] Open
Abstract
Single-cell sequencing technologies have led to a revolution in our knowledge of the diversity of cell types, connections between biological levels of organization, and relationships between genotype and phenotype. These advances have mainly come from using model organisms; however, using single-cell sequencing in non-model organisms could enable investigations of questions inaccessible with typical model organisms. This primer describes a general workflow for single-cell sequencing studies and considerations for using non-model organisms (limited to multicellular animals). Importantly, single-cell sequencing, when further applied in non-model organisms, will allow for a deeper understanding of the mechanisms between genotype and phenotype and the basis for biological variation.
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Affiliation(s)
- James M. Alfieri
- Department of Biology, Texas A&M University, College Station, TX 77843, USA; (M.M.J.); (H.B.)
- Interdisciplinary Program in Ecology and Evolutionary Biology, Texas A&M University, College Station, TX 77843, USA;
- Department of Poultry Science, Texas A&M University, College Station, TX 77843, USA
| | - Guosong Wang
- Department of Animal Science, Texas A&M University, College Station, TX 77843, USA; (G.W.); (C.A.G.)
| | - Michelle M. Jonika
- Department of Biology, Texas A&M University, College Station, TX 77843, USA; (M.M.J.); (H.B.)
- Interdisciplinary Program in Genetics and Genomics, Texas A&M University, College Station, TX 77843, USA
| | - Clare A. Gill
- Department of Animal Science, Texas A&M University, College Station, TX 77843, USA; (G.W.); (C.A.G.)
- Interdisciplinary Program in Genetics and Genomics, Texas A&M University, College Station, TX 77843, USA
| | - Heath Blackmon
- Department of Biology, Texas A&M University, College Station, TX 77843, USA; (M.M.J.); (H.B.)
- Interdisciplinary Program in Ecology and Evolutionary Biology, Texas A&M University, College Station, TX 77843, USA;
- Interdisciplinary Program in Genetics and Genomics, Texas A&M University, College Station, TX 77843, USA
| | - Giridhar N. Athrey
- Interdisciplinary Program in Ecology and Evolutionary Biology, Texas A&M University, College Station, TX 77843, USA;
- Department of Poultry Science, Texas A&M University, College Station, TX 77843, USA
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48
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Koochekian N, Ascanio A, Farleigh K, Card DC, Schield DR, Castoe TA, Jezkova T. A chromosome-level genome assembly and annotation of the desert horned lizard, Phrynosoma platyrhinos, provides insight into chromosomal rearrangements among reptiles. Gigascience 2022; 11:giab098. [PMID: 35134927 PMCID: PMC8848323 DOI: 10.1093/gigascience/giab098] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Revised: 09/27/2021] [Accepted: 12/15/2021] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND The increasing number of chromosome-level genome assemblies has advanced our knowledge and understanding of macroevolutionary processes. Here, we introduce the genome of the desert horned lizard, Phrynosoma platyrhinos, an iguanid lizard occupying extreme desert conditions of the American southwest. We conduct analysis of the chromosomal structure and composition of this species and compare these features across genomes of 12 other reptiles (5 species of lizards, 3 snakes, 3 turtles, and 1 bird). FINDINGS The desert horned lizard genome was sequenced using Illumina paired-end reads and assembled and scaffolded using Dovetail Genomics Hi-C and Chicago long-range contact data. The resulting genome assembly has a total length of 1,901.85 Mb, scaffold N50 length of 273.213 Mb, and includes 5,294 scaffolds. The chromosome-level assembly is composed of 6 macrochromosomes and 11 microchromosomes. A total of 20,764 genes were annotated in the assembly. GC content and gene density are higher for microchromosomes than macrochromosomes, while repeat element distributions show the opposite trend. Pathway analyses provide preliminary evidence that microchromosome and macrochromosome gene content are functionally distinct. Synteny analysis indicates that large microchromosome blocks are conserved among closely related species, whereas macrochromosomes show evidence of frequent fusion and fission events among reptiles, even between closely related species. CONCLUSIONS Our results demonstrate dynamic karyotypic evolution across Reptilia, with frequent inferred splits, fusions, and rearrangements that have resulted in shuffling of chromosomal blocks between macrochromosomes and microchromosomes. Our analyses also provide new evidence for distinct gene content and chromosomal structure between microchromosomes and macrochromosomes within reptiles.
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Affiliation(s)
| | - Alfredo Ascanio
- Department of Biology, Miami University, Oxford, OH 45056, USA
| | - Keaka Farleigh
- Department of Biology, Miami University, Oxford, OH 45056, USA
| | - Daren C Card
- Department of Organismic & Evolutionary Biology, Harvard University, Cambridge, MA 02138, USA
- Museum of Comparative Zoology, Harvard University, Cambridge, MA 02138, USA
| | - Drew R Schield
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, CO 80309, USA
| | - Todd A Castoe
- Department of Biology, University of Texas at Arlington, Arlington, TX 76019, USA
| | - Tereza Jezkova
- Department of Biology, Miami University, Oxford, OH 45056, USA
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49
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Zancolli G, Reijnders M, Waterhouse RM, Robinson-Rechavi M. Convergent evolution of venom gland transcriptomes across Metazoa. Proc Natl Acad Sci U S A 2022; 119:e2111392119. [PMID: 34983844 PMCID: PMC8740685 DOI: 10.1073/pnas.2111392119] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/10/2021] [Indexed: 12/13/2022] Open
Abstract
Animals have repeatedly evolved specialized organs and anatomical structures to produce and deliver a mixture of potent bioactive molecules to subdue prey or predators-venom. This makes it one of the most widespread, convergent functions in the animal kingdom. Whether animals have adopted the same genetic toolkit to evolved venom systems is a fascinating question that still eludes us. Here, we performed a comparative analysis of venom gland transcriptomes from 20 venomous species spanning the main Metazoan lineages to test whether different animals have independently adopted similar molecular mechanisms to perform the same function. We found a strong convergence in gene expression profiles, with venom glands being more similar to each other than to any other tissue from the same species, and their differences closely mirroring the species phylogeny. Although venom glands secrete some of the fastest evolving molecules (toxins), their gene expression does not evolve faster than evolutionarily older tissues. We found 15 venom gland-specific gene modules enriched in endoplasmic reticulum stress and unfolded protein response pathways, indicating that animals have independently adopted stress response mechanisms to cope with mass production of toxins. This, in turn, activates regulatory networks for epithelial development, cell turnover, and maintenance, which seem composed of both convergent and lineage-specific factors, possibly reflecting the different developmental origins of venom glands. This study represents a first step toward an understanding of the molecular mechanisms underlying the repeated evolution of one of the most successful adaptive traits in the animal kingdom.
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Affiliation(s)
- Giulia Zancolli
- Department of Ecology and Evolution, University of Lausanne, Lausanne 1015, Switzerland;
- Evolutionary Bioinformatics Group, Swiss Institute of Bioinformatics, Lausanne 1015, Switzerland
| | - Maarten Reijnders
- Department of Ecology and Evolution, University of Lausanne, Lausanne 1015, Switzerland
- Evolutionary-Functional Genomics Group, Swiss Institute of Bioinformatics, Lausanne 1015, Switzerland
| | - Robert M Waterhouse
- Department of Ecology and Evolution, University of Lausanne, Lausanne 1015, Switzerland
- Evolutionary-Functional Genomics Group, Swiss Institute of Bioinformatics, Lausanne 1015, Switzerland
| | - Marc Robinson-Rechavi
- Department of Ecology and Evolution, University of Lausanne, Lausanne 1015, Switzerland
- Evolutionary Bioinformatics Group, Swiss Institute of Bioinformatics, Lausanne 1015, Switzerland
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Population genetic and genomic analyses of Western Massasauga (Sistrurus tergeminus ssp.): implications for subspecies delimitation and conservation. CONSERV GENET 2021. [DOI: 10.1007/s10592-021-01420-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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