1
|
Klymus KE, Hrabik RA, Thompson NL, Cornman RS. Genome resequencing clarifies phylogeny and reveals patterns of selection in the toxicogenomics model Pimephales promelas. PeerJ 2022; 10:e13954. [PMID: 36042859 PMCID: PMC9420404 DOI: 10.7717/peerj.13954] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Accepted: 08/05/2022] [Indexed: 01/19/2023] Open
Abstract
Background The fathead minnow (Pimephales promelas) is a model species for toxicological research. A high-quality genome reference sequence is available, and genomic methods are increasingly used in toxicological studies of the species. However, phylogenetic relationships within the genus remain incompletely known and little population-genomic data are available for fathead minnow despite the potential effects of genetic background on toxicological responses. On the other hand, a wealth of extant samples is stored in museum collections that in principle allow fine-scale analysis of contemporary and historical genetic variation. Methods Here we use short-read shotgun resequencing to investigate sequence variation among and within Pimephales species. At the genus level, our objectives were to resolve phylogenetic relationships and identify genes with signatures of positive diversifying selection. At the species level, our objective was to evaluate the utility of archived-sample resequencing for detecting selective sweeps within fathead minnow, applied to a population introduced to the San Juan River of the southwestern United States sometime prior to 1950. Results We recovered well-supported but discordant phylogenetic topologies for nuclear and mitochondrial sequences that we hypothesize arose from mitochondrial transfer among species. The nuclear tree supported bluntnose minnow (P. notatus) as sister to fathead minnow, with the slim minnow (P. tenellus) and bullhead minnow (P. vigilax) more closely related to each other. Using multiple methods, we identified 11 genes that have diversified under positive selection within the genus. Within the San Juan River population, we identified selective-sweep regions overlapping several sets of related genes, including both genes that encode the giant sarcomere protein titin and the two genes encoding the MTORC1 complex, a key metabolic regulator. We also observed elevated polymorphism and reduced differentation among populations (FST) in genomic regions containing certain immune-gene clusters, similar to what has been reported in other taxa. Collectively, our data clarify evolutionary relationships and selective pressures within the genus and establish museum archives as a fruitful resource for characterizing genomic variation. We anticipate that large-scale resequencing will enable the detection of genetic variants associated with environmental toxicants such as heavy metals, high salinity, estrogens, and agrichemicals, which could be exploited as efficient biomarkers of exposure in natural populations.
Collapse
Affiliation(s)
- Katy E. Klymus
- U.S. Geological Survey, Columbia Ecological Research Center, Columbia, MO, USA
| | | | - Nathan L. Thompson
- U.S. Geological Survey, Columbia Ecological Research Center, Columbia, MO, USA
| | - Robert S. Cornman
- U.S. Geological Survey, Fort Collins Science Center, Fort Collins, CO, USA
| |
Collapse
|
2
|
Duarte MA, Fernandes CR, Heckel G, da Luz Mathias M, Bastos-Silveira C. Variation and Selection in the Putative Sperm-Binding Region of ZP3 in Muroid Rodents: A Comparison between Cricetids and Murines. Genes (Basel) 2021; 12:genes12091450. [PMID: 34573431 PMCID: PMC8469249 DOI: 10.3390/genes12091450] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Revised: 09/15/2021] [Accepted: 09/16/2021] [Indexed: 11/16/2022] Open
Abstract
In mammals, the zona pellucida glycoprotein 3 (ZP3) is considered a primary sperm receptor of the oocyte and is hypothesized to be involved in reproductive isolation. We investigated patterns of diversity and selection in the putative sperm-binding region (pSBR) of mouse ZP3 across Cricetidae and Murinae, two hyperdiverse taxonomic groups within muroid rodents. In murines, the pSBR is fairly conserved, in particular the serine-rich stretch containing the glycosylation sites proposed as essential for sperm binding. In contrast, cricetid amino acid sequences of the pSBR were much more variable and the serine-rich motif, typical of murines, was generally substantially modified. Overall, our results suggest a general lack of species specificity of the pSBR across the two muroid families. We document statistical evidence of positive selection acting on exons 6 and 7 of ZP3 and identified several amino acid sites that are likely targets of selection, with most positively selected sites falling within or adjacent to the pSBR.
Collapse
Affiliation(s)
- Margarida Alexandra Duarte
- Champalimaud Centre for the Uknown, Champalimaud Research, Champalimaud Foundation, Avenida Brasília, 1400-038 Lisboa, Portugal
- Museu Nacional de História Natural e da Ciência, Departamento de Zoologia e Antropologia, Universidade de Lisboa, Rua da Escola Politécnica, 58, Lisboa, 1250-102 Lisboa, Portugal
- Departamento de Biologia Animal, Faculdade de Ciências da Universidade de Lisboa, Campo Grande, 1749-016 Lisboa, Portugal;
- Centro de Estudos de Ambiente e Mar, Faculdade de Ciências da Universidade de Lisboa, Campo Grande, 1749-016 Lisboa, Portugal
- Correspondence:
| | - Carlos Rodríguez Fernandes
- cE3c-Centre for Ecology, Evolution and Environmental Changes, Departamento de Biologia Animal, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal; (C.R.F.); (C.B.-S.)
- Faculdade de Psicologia, Universidade de Lisboa, Alameda da Universidade, 1649-013 Lisboa, Portugal
| | - Gerald Heckel
- Institute of Ecology and Evolution, University of Bern, Baltzerstrasse 6, CH-3012 Bern, Switzerland;
- SIB Swiss Institute of Bioinformatics, Quartier Sorge-Batiment Amphipole, CH-1015 Lausanne, Switzerland
| | - Maria da Luz Mathias
- Departamento de Biologia Animal, Faculdade de Ciências da Universidade de Lisboa, Campo Grande, 1749-016 Lisboa, Portugal;
- Centro de Estudos de Ambiente e Mar, Faculdade de Ciências da Universidade de Lisboa, Campo Grande, 1749-016 Lisboa, Portugal
| | - Cristiane Bastos-Silveira
- cE3c-Centre for Ecology, Evolution and Environmental Changes, Departamento de Biologia Animal, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal; (C.R.F.); (C.B.-S.)
| |
Collapse
|
3
|
Killingbeck EE, Wilburn DB, Merrihew GE, MacCoss MJ, Swanson WJ. Proteomics support the threespine stickleback egg coat as a protective oocyte envelope. Mol Reprod Dev 2021; 88:500-515. [PMID: 34148267 PMCID: PMC8362008 DOI: 10.1002/mrd.23517] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Revised: 05/20/2021] [Accepted: 05/22/2021] [Indexed: 12/20/2022]
Abstract
Ancestrally marine threespine stickleback fish (Gasterosteus aculeatus) have undergone an adaptive radiation into freshwater environments throughout the Northern Hemisphere, creating an excellent model system for studying molecular adaptation and speciation. Ecological and behavioral factors have been suggested to underlie stickleback reproductive isolation and incipient speciation, but reproductive proteins mediating gamete recognition during fertilization have so far remained unexplored. To begin to investigate the contribution of reproductive proteins to stickleback reproductive isolation, we have characterized the stickleback egg coat proteome. We find that stickleback egg coats are comprised of homologs to the zona pellucida (ZP) proteins ZP1 and ZP3, as in other teleost fish. Our molecular evolutionary analyses indicate that across teleosts, ZP3 but not ZP1 has experienced positive Darwinian selection. Mammalian ZP3 is also rapidly evolving, and surprisingly some residues under selection in stickleback and mammalian ZP3 directly align. Despite broad homology, however, we find differences between mammalian and stickleback ZP proteins with respect to glycosylation, disulfide bonding, and sites of synthesis. Taken together, the changes we observe in stickleback ZP protein architecture suggest that the egg coats of stickleback fish, and perhaps fish more generally, have evolved to fulfill a more protective functional role than their mammalian counterparts.
Collapse
Affiliation(s)
- Emily E Killingbeck
- Department of Genome Sciences, University of Washington, Seattle, Washington, USA
| | - Damien B Wilburn
- Department of Genome Sciences, University of Washington, Seattle, Washington, USA
| | - Gennifer E Merrihew
- Department of Genome Sciences, University of Washington, Seattle, Washington, USA
| | - Michael J MacCoss
- Department of Genome Sciences, University of Washington, Seattle, Washington, USA
| | - Willie J Swanson
- Department of Genome Sciences, University of Washington, Seattle, Washington, USA
| |
Collapse
|
4
|
Keeble S, Firman RC, Sarver BAJ, Clark NL, Simmons LW, Dean MD. Evolutionary, proteomic, and experimental investigations suggest the extracellular matrix of cumulus cells mediates fertilization outcomes. Biol Reprod 2021; 105:1043-1055. [PMID: 34007991 DOI: 10.1093/biolre/ioab082] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Revised: 01/29/2021] [Accepted: 04/21/2021] [Indexed: 12/20/2022] Open
Abstract
Studies of fertilization biology often focus on sperm and egg interactions. However, before gametes interact, mammalian sperm must pass through the cumulus layer; in mice, this consists of several thousand cells tightly glued together with hyaluronic acid and other proteins. To better understand the role of cumulus cells and their surrounding matrix, we perform proteomic experiments on cumulus oophorus complexes (COCs) in house mice (Mus musculus), producing over 24,000 mass spectra to identify 711 proteins. Seven proteins known to stabilize hyaluronic acid and the extracellular matrix were especially abundant (using spectral counts as an indirect proxy for abundance). Through comparative evolutionary analyses, we show that three of these evolve rapidly, a classic signature of genes that influence fertilization rate. Some of the selected sites overlap regions of the protein known to impact function. In a follow-up experiment, we compared COCs from females raised in two different social environments. Female mice raised in the presence of multiple males produced COCs that were smaller and more resistant to sperm-derived hyaluronidase compared to females raised in the presence of a single male, consistent with a previous study that demonstrated such females produced COCs that were more resistant to fertilization. Although cumulus cells are often thought of as enhancers of fertilization, our evolutionary, proteomic, and experimental investigations implicate their extracellular matrix as a potential mediator of fertilization outcomes.
Collapse
Affiliation(s)
- Sara Keeble
- Molecular and Computational Biology, Department of Biological Sciences, University of Southern California, Los Angeles, California
| | - Renée C Firman
- Centre for Evolutionary Biology, School of Biological Sciences (M092), University of Western Australia, Australia
| | - Brice A J Sarver
- Division of Biological Sciences, University of Montana, Missoula, Montana
| | - Nathan L Clark
- Department of Human Genetics, University of Utah, Salt Lake City, Utah
| | - Leigh W Simmons
- Centre for Evolutionary Biology, School of Biological Sciences (M092), University of Western Australia, Australia
| | - Matthew D Dean
- Molecular and Computational Biology, Department of Biological Sciences, University of Southern California, Los Angeles, California
| |
Collapse
|
5
|
Morgan CC, Hart MW. Molecular evolution of mammalian genes with epistatic interactions in fertilization. BMC Evol Biol 2019; 19:154. [PMID: 31345177 PMCID: PMC6659299 DOI: 10.1186/s12862-019-1480-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Accepted: 07/16/2019] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Genes that encode proteins associated with sperm competition, fertilization, and sexual conflicts of interest are often among the most rapidly evolving parts of animal genomes. One family of sperm-expressed genes (Zp3r, C4bpa) in the mammalian gene cluster called the regulator of complement activation (RCA) encodes proteins that bind eggs and mediate reproductive success, and are therefore expected to show high relative rates of nonsynonymous nucleotide substitution in response to sexual selection in comparison to other genes not involved in gamete binding at fertilization. We tested that working hypothesis by using phylogenetic models of codon evolution to identify episodes of diversifying positive selection. We used a comparative approach to quantify the evidence for episodic diversifying selection acting on RCA genes with known functions in fertilization (and sensitivity to sexual selection), and contrast them with other RCA genes in the same gene family that function in innate immunity (and are not sensitive to sexual selection). RESULTS We expected but did not find evidence for more episodes of positive selection on Zp3r in Glires (the rodents and lagomorphs) or on C4BPA in Primates, in comparison to other paralogous RCA genes in the same taxon, or in comparison to the same orthologous RCA gene in the other taxon. That result was not unique to RCA genes: we also found little evidence for more episodes of diversifying selection on genes that encode selective sperm-binding molecules in the egg coat or zona pellucida (Zp2, Zp3) in comparison to members of the same gene family that encode structural elements of the egg coat (Zp1, Zp4). Similarly, we found little evidence for episodic diversifying selection acting on two other recently discovered genes (Juno, Izumo1) that encode essential molecules for sperm-egg fusion. CONCLUSIONS These negative results help to illustrate the importance of a comparative context for this type of codon model analysis. The results may also point to other phylogenetic contexts in which the effects of selection acting on these fertilization proteins might be more readily discovered and documented in mammals and other taxa.
Collapse
Affiliation(s)
- Claire C. Morgan
- Department of Medicine, Imperial College London, London, W12 0NN UK
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Michael W. Hart
- Department of Biological Sciences, Simon Fraser University, Burnaby, British Columbia V5A 1S6 Canada
| |
Collapse
|
6
|
Hart MW, Stover DA, Guerra V, Mozaffari SV, Ober C, Mugal CF, Kaj I. Positive selection on human gamete-recognition genes. PeerJ 2018; 6:e4259. [PMID: 29340252 PMCID: PMC5767332 DOI: 10.7717/peerj.4259] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2017] [Accepted: 12/21/2017] [Indexed: 01/29/2023] Open
Abstract
Coevolution of genes that encode interacting proteins expressed on the surfaces of sperm and eggs can lead to variation in reproductive compatibility between mates and reproductive isolation between members of different species. Previous studies in mice and other mammals have focused in particular on evidence for positive or diversifying selection that shapes the evolution of genes that encode sperm-binding proteins expressed in the egg coat or zona pellucida (ZP). By fitting phylogenetic models of codon evolution to data from the 1000 Genomes Project, we identified candidate sites evolving under diversifying selection in the human genes ZP3 and ZP2. We also identified one candidate site under positive selection in C4BPA, which encodes a repetitive protein similar to the mouse protein ZP3R that is expressed in the sperm head and binds to the ZP at fertilization. Results from several additional analyses that applied population genetic models to the same data were consistent with the hypothesis of selection on those candidate sites leading to coevolution of sperm- and egg-expressed genes. By contrast, we found no candidate sites under selection in a fourth gene (ZP1) that encodes an egg coat structural protein not directly involved in sperm binding. Finally, we found that two of the candidate sites (in C4BPA and ZP2) were correlated with variation in family size and birth rate among Hutterite couples, and those two candidate sites were also in linkage disequilibrium in the same Hutterite study population. All of these lines of evidence are consistent with predictions from a previously proposed hypothesis of balancing selection on epistatic interactions between C4BPA and ZP3 at fertilization that lead to the evolution of co-adapted allele pairs. Such patterns also suggest specific molecular traits that may be associated with both natural reproductive variation and clinical infertility.
Collapse
Affiliation(s)
- Michael W Hart
- Department of Biological Sciences, Simon Fraser University, Burnaby, British Columbia, Canada
| | - Daryn A Stover
- School of Mathematical and Natural Sciences, Arizona State University Colleges at Lake Havasu City, Lake Havasu City, AZ, USA
| | - Vanessa Guerra
- Department of Biological Sciences, Simon Fraser University, Burnaby, British Columbia, Canada
| | - Sahar V Mozaffari
- Department of Human Genetics, University of Chicago, Chicago, IL, USA
| | - Carole Ober
- Department of Human Genetics, University of Chicago, Chicago, IL, USA
| | - Carina F Mugal
- Department of Ecology and Genetics, Uppsala University, Uppsala, Sweden
| | - Ingemar Kaj
- Department of Mathematics, Uppsala University, Uppsala, Sweden
| |
Collapse
|
7
|
Genes Integral to the Reproductive Function of Male Reproductive Tissues Drive Heterogeneity in Evolutionary Rates in Japanese Quail. G3-GENES GENOMES GENETICS 2018; 8:39-51. [PMID: 29158338 PMCID: PMC5765365 DOI: 10.1534/g3.117.300095] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Early comparative genomics studies originally uncovered a nonintuitive pattern; genes involved in reproduction appeared to evolve more rapidly than other classes of genes. Currently, the emerging consensus is that genes encoding reproductive proteins evolve under variable selective pressures, producing more heterogeneous divergence patterns than previously appreciated. Here, we investigate a facet of that heterogeneity and explore the factors that drive male reproductive tissue-based heterogeneity in evolutionary rates. In Japanese quail (Coturnix japonica), genes with enriched expression in the testes evolve much more rapidly than those enriched in the foam gland (FG), a novel gland that secretes an airy foam that males transfer to females during mating. We compared molecular evolutionary patterns among (1) genes with induced expression in breeding vs. wintering conditions for both tissues and (2) genes that encode foam proteins (FPs) vs. those with varying degrees of expression specificity in the FG. We report two major findings. First, genes upregulated in breeding condition testes evolve exceptionally rapidly, while those induced in breeding condition FGs evolve slowly. These differences hold even after correcting for hormonally-dependent gene expression and chromosomal location. Second, genes encoding FPs are extremely conserved in terms of gene identity and sequence. Together, these finding suggest that genes involved in the reproductive function of each tissue drive the marked rate of heterogeneity.
Collapse
|
8
|
Goenaga J, Yamane T, Rönn J, Arnqvist G. Within-species divergence in the seminal fluid proteome and its effect on male and female reproduction in a beetle. BMC Evol Biol 2015; 15:266. [PMID: 26627998 PMCID: PMC4667481 DOI: 10.1186/s12862-015-0547-2] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2015] [Accepted: 11/20/2015] [Indexed: 11/30/2022] Open
Abstract
Background Male seminal fluid proteins (SFPs), transferred to females during mating, are important reproductive proteins that have multifarious effects on female reproductive physiology and that often show remarkably rapid and divergent evolution. Inferences regarding natural selection on SFPs are based primarily on interspecific comparative studies, and our understanding of natural within-species variation in SFPs and whether this relates to reproductive phenotypes is very limited. Here, we introduce an empirical strategy to study intraspecific variation in and selection upon the seminal fluid proteome. We then apply this in a study of 15 distinct populations of the seed beetle Callosobruchus maculatus. Results Phenotypic assays of these populations showed significant differences in reproductive phenotypes (male success in sperm competition and male ability to stimulate female fecundity). A quantitative proteomic study of replicated samples of male accessory glands revealed a large number of potential SFPs, of which ≥127 were found to be transferred to females at mating. Moreover, population divergence in relative SFP abundance across populations was large and remarkably multidimensional. Most importantly, variation in male SFP abundance across populations was associated with male sperm competition success and male ability to stimulate female egg production. Conclusions Our study provides the first direct evidence for postmating sexual selection on standing intraspecific variation in SFP abundance and the pattern of divergence across populations in the seminal fluid proteome match the pattern predicted by the postmating sexual selection paradigm for SFP evolution. Our findings provide novel support for the hypothesis that sexual selection on SFPs is an important engine of incipient speciation. Electronic supplementary material The online version of this article (doi:10.1186/s12862-015-0547-2) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Julieta Goenaga
- Animal Ecology, Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, Norbyvägen 18D, SE-752 36, Uppsala, Sweden. .,Aarhus Institute of Advanced Studies, Aarhus University, Høegh-Guldbergs Gade 6B, 11 8000, Aarhus C, Denmark.
| | - Takashi Yamane
- Animal Ecology, Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, Norbyvägen 18D, SE-752 36, Uppsala, Sweden.
| | - Johanna Rönn
- Animal Ecology, Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, Norbyvägen 18D, SE-752 36, Uppsala, Sweden.
| | - Göran Arnqvist
- Animal Ecology, Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, Norbyvägen 18D, SE-752 36, Uppsala, Sweden.
| |
Collapse
|
9
|
Some assembly required: evolutionary and systems perspectives on the mammalian reproductive system. Cell Tissue Res 2015; 363:267-278. [DOI: 10.1007/s00441-015-2257-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2015] [Accepted: 07/05/2015] [Indexed: 12/30/2022]
|
10
|
Shu L, Suter MJF, Räsänen K. Evolution of egg coats: linking molecular biology and ecology. Mol Ecol 2015; 24:4052-73. [DOI: 10.1111/mec.13283] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2014] [Revised: 06/12/2015] [Accepted: 06/17/2015] [Indexed: 12/18/2022]
Affiliation(s)
- Longfei Shu
- Department of Aquatic Ecology; Swiss Federal Institute of Aquatic Science and Technology; Eawag; 8600 Duebendorf Switzerland
- Institute of Integrative Biology; ETH Zurich; 8092 Zurich Switzerland
| | - Marc J.-F. Suter
- Department of Environmental Toxicology; Swiss Federal Institute of Aquatic Science and Technology; Eawag; 8600 Duebendorf Switzerland
- Department of Environmental Systems Science; Swiss Federal Institute of Technology; ETH Zurich; 8092 Zurich Switzerland
| | - Katja Räsänen
- Department of Aquatic Ecology; Swiss Federal Institute of Aquatic Science and Technology; Eawag; 8600 Duebendorf Switzerland
- Institute of Integrative Biology; ETH Zurich; 8092 Zurich Switzerland
| |
Collapse
|
11
|
Kosman ET, Levitan DR. Sperm competition and the evolution of gametic compatibility in externally fertilizing taxa. Mol Hum Reprod 2014; 20:1190-7. [PMID: 25323969 DOI: 10.1093/molehr/gau069] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Proteins expressed on the surface of sperm and egg mediate gametic compatibility and these proteins can be subject to intense positive selection. In this review, we discuss what is known about the patterns of adaptive evolution of gamete recognition proteins (GRPs). We focus on species that broadcast eggs and sperm into the environment for external fertilization, as the ease of observing and manipulating gamete interactions has allowed for greater advances in the understanding of GRP evolution, uncomplicated by confounding behavioral and physiological components that offer alternative evolutionary targets in internal fertilizers. We discuss whether interspecific mechanisms, such as selection to avoid fertilization between species (reinforcement selection), or intraspecific mechanisms, such as selection to increase (or decrease) the affinity between eggs and sperm based on the intensity of sperm competition, may be responsible for the pattern of GRP evolution observed. Variation in these proteins appears to influence gametic compatibility; GRP divergence among species is a better predictor of hybrid fertilization than neutral genetic markers and GRP variation within species predicts reproductive success among individuals within a population. Evidence suggests that sperm competition may play a large role in the evolution of gametic compatibility.
Collapse
Affiliation(s)
- E T Kosman
- Department of Biological Science, Florida State University, Tallahassee, FL 32306, USA
| | - D R Levitan
- Department of Biological Science, Florida State University, Tallahassee, FL 32306, USA
| |
Collapse
|
12
|
Hellberg ME, Dennis AB, Arbour-Reily P, Aagaard JE, Swanson WJ. The Tegula tango: a coevolutionary dance of interacting, positively selected sperm and egg proteins. Evolution 2012; 66:1681-94. [PMID: 22671539 DOI: 10.1111/j.1558-5646.2011.01530.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Reproductive proteins commonly show signs of rapid divergence driven by positive selection. The mechanisms driving these changes have remained ambiguous in part because interacting male and female proteins have rarely been examined. We isolate an egg protein the vitelline envelope receptor for lysin (VERL) from Tegula, a genus of free-spawning marine snails. Like VERL from abalone, Tegula VERL is a major component of the VE surrounding the egg, includes a conserved zona pellucida (ZP) domain at its C-terminus, and possesses a unique, negatively charged domain of about 150 amino acids implicated in interactions with the positively charged lysin. Unlike for abalone VERL, where this unique VERL domain occurs in a tandem array of 22 repeats, Tegula VERL has just one such domain. Interspecific comparisons show that both lysin and the VERL domain diverge via positive selection, whereas the ZP domain evolves neutrally. Rates of nonsynonymous substitution are correlated between lysin and the VERL domain, consistent with sexual antagonism, although lineage-specific effects, perhaps owing to different ecologies, may alter the relative evolutionary rates of sperm- and egg-borne proteins.
Collapse
Affiliation(s)
- Michael E Hellberg
- Department of Biological Sciences, Louisiana State University, Baton Rouge, Louisiana 70803, USA.
| | | | | | | | | |
Collapse
|
13
|
Chen S, Costa V, Beja-Pereira A. Evolutionary patterns of two major reproduction candidate genes (Zp2 and Zp3) reveal no contribution to reproductive isolation between bovine species. BMC Evol Biol 2011; 11:24. [PMID: 21266067 PMCID: PMC3037879 DOI: 10.1186/1471-2148-11-24] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2010] [Accepted: 01/25/2011] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND It has been established that mammalian egg zona pellucida (ZP) glycoproteins are responsible for species-restricted binding of sperm to unfertilized eggs, inducing the sperm acrosome reaction, and preventing polyspermy. In mammals, ZP apparently represents a barrier to heterospecific fertilization and thus probably contributes to reproductive isolation between species. The evolutionary relationships between some members of the tribe Bovini are complex and highly debatable, particularly, those involving Bos and Bison species for which interspecific hybridization is extensively documented. Because reproductive isolation is known to be a major precursor of species divergence, testing evolutionary patterns of ZP glycoproteins may shed some light into the speciation process of these species. To this end, we have examined intraspecific and interspecific genetic variation of two ZP genes (Zp2 and Zp3) for seven representative species (111 individuals) from the Bovini tribe, including five species from Bos and Bison, and two species each from genera Bubalus and Syncerus. RESULTS A pattern of low levels of intraspecific polymorphism and interspecific divergence was detected for the two sequenced fragments each for Zp2 and Zp3. At intraspecific level, none of neutrality tests detected deviations from neutral equilibrium expectations for the two genes. Several haplotypes in both genes were shared by multiple species from Bos and Bison. CONCLUSIONS Here we argue that neither ancestral polymorphism nor introgressive hybridization alone can fully account for haplotype sharing among species from Bos and Bison, and that both scenarios have contributed to such a pattern of haplotype sharing observed here. Additionally, codon-based tests revealed strong evidence for purifying selection in the Zp3 coding haplotype sequences and weak evidence for purifying selection in the Zp2 coding haplotype sequences. Contrary to a general genetic pattern that genes or genomic regions contributing to reproductive isolation between species often evolve rapidly and show little or no gene flow between species, these results demonstrate that, particularly, those sequenced exons of the Zp2 and the Zp3 did not show any contribution to reproductive isolation between the bovine species studied here.
Collapse
Affiliation(s)
- Shanyuan Chen
- Centro de Investigação em Biodiversidade e Recursos Genéticos da Universidade do Porto, Campus Agrário de Vairão, 4485-661 Vairão, Portugal
| | | | | |
Collapse
|
14
|
Tomaiuolo M, Levitan D. Modeling How Reproductive Ecology Can Drive Protein Diversification and Result in Linkage Disequilibrium between Sperm and Egg Proteins. Am Nat 2010; 176:14-25. [DOI: 10.1086/652999] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
|
15
|
Levitan DR, Stapper AP. Simultaneous positive and negative frequency-dependent selection on sperm bindin, a gamete recognition protein in the sea urchin Strongylocentrotus purpuratus. Evolution 2009; 64:785-97. [PMID: 19796148 DOI: 10.1111/j.1558-5646.2009.00850.x] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Gamete-recognition proteins often, but not always, evolve rapidly. We explored how variation in sperm bindin influences reproductive success of the sea urchin Strongylocentrotus purpuratus during group spawning in the sea. Despite large variation in male and female abundance and neighbor distances, males with common genotypes had higher reproductive success than males with rare genotypes. However, males with a relatively uncommon proline-for-serine substitution were the most successful. Females also showed a fitness consequence of sperm-bindin genotype, suggesting linkage disequilibrium between the sperm-bindin locus and the egg receptor locus. Females with common genotypes had higher reproductive success than rare genotypes, but females with relatively uncommon insertions were most successful. Overall, these results suggest that rare male proteins are selected against, as supported by molecular evidence of purifying selection and probably caused by poor matches to the female receptor protein. Within the pool of moderately common to common alleles, however, individuals with less-common functional variants were favored and probably maintained by negative frequency-dependent selection. These results support the hypothesis that sperm availability and sexual conflict influence the evolution of gamete recognition systems in broadcast spawners and highlight the benefits of combining fitness measures with molecular signatures for estimation of patterns of selection.
Collapse
Affiliation(s)
- Don R Levitan
- Department of Biological Science, Florida State University, Tallahassee, Florida 32306, USA.
| | | |
Collapse
|
16
|
Barroso G, Valdespin C, Vega E, Kershenovich R, Avila R, Avendaño C, Oehninger S. Developmental sperm contributions: fertilization and beyond. Fertil Steril 2009; 92:835-848. [PMID: 19631936 DOI: 10.1016/j.fertnstert.2009.06.030] [Citation(s) in RCA: 92] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2008] [Revised: 06/16/2009] [Accepted: 06/16/2009] [Indexed: 10/20/2022]
|
17
|
Current World Literature. Curr Opin Lipidol 2009; 20:135-42. [PMID: 19276892 DOI: 10.1097/mol.0b013e32832a7e09] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
|
18
|
Duplication, selection and gene conversion in a Drosophila mojavensis female reproductive protein family. Genetics 2009; 181:1451-65. [PMID: 19204376 DOI: 10.1534/genetics.108.099044] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Protein components of the Drosophila male ejaculate, several of which evolve rapidly, are critical modulators of reproductive success. Recent studies of female reproductive tract proteins indicate they also are extremely divergent between species, suggesting that reproductive molecules may coevolve between the sexes. Our current understanding of intersexual coevolution, however, is severely limited by the paucity of genetic and evolutionary studies on the female molecules involved. Physiological evidence of ejaculate-female coadaptation, paired with a promiscuous mating system, makes Drosophila mojavensis an exciting model system in which to study the evolution of reproductive proteins. Here we explore the evolutionary dynamics of a five-paralog gene family of female reproductive proteases within populations of D. mojavensis and throughout the repleta species group. We show that the proteins have experienced ongoing gene duplication and adaptive evolution and further exhibit dynamic patterns of pseudogenation, copy number variation, gene conversion, and selection within geographically isolated populations of D. mojavensis. The integration of these patterns in a single gene family has never before been documented in a reproductive protein.
Collapse
|
19
|
Abstract
Genes expressed in testes are critical to male reproductive success, affecting spermatogenesis, sperm competition, and sperm-egg interaction. Comparing the evolution of testis proteins at different taxonomic levels can reveal which genes and functional classes are targets of natural and sexual selection and whether the same genes are targets among taxa. Here we examine the evolution of testis-expressed proteins at different levels of divergence among three rodents, mouse (Mus musculus), rat (Rattus norvegicus), and deer mouse (Peromyscus maniculatus), to identify rapidly evolving genes. Comparison of expressed sequence tags (ESTs) from testes suggests that proteins with testis-specific expression evolve more rapidly on average than proteins with maximal expression in other tissues. Genes with the highest rates of evolution have a variety of functional roles including signal transduction, DNA binding, and egg-sperm interaction. Most of these rapidly evolving genes have not been identified previously as targets of selection in comparisons among more divergent mammals. To determine if these genes are evolving rapidly among closely related species, we sequenced 11 of these genes in six Peromyscus species and found evidence for positive selection in five of them. Together, these results demonstrate rapid evolution of functionally diverse testis-expressed proteins in rodents, including the identification of amino acids under lineage-specific selection in Peromyscus. Evidence for positive selection among closely related species suggests that changes in these proteins may have consequences for reproductive isolation.
Collapse
|