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Delaye L, Ruiz-Ruiz S, Calderon E, Tarazona S, Conesa A, Moya A. Evidence of the Red-Queen Hypothesis from Accelerated Rates of Evolution of Genes Involved in Biotic Interactions in Pneumocystis. Genome Biol Evol 2018; 10:1596-1606. [PMID: 29893833 PMCID: PMC6012782 DOI: 10.1093/gbe/evy116] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/05/2018] [Indexed: 01/15/2023] Open
Abstract
Pneumocystis species are ascomycete fungi adapted to live inside the lungs of mammals. These ascomycetes show extensive stenoxenism, meaning that each species of Pneumocystis infects a single species of host. Here, we study the effect exerted by natural selection on gene evolution in the genomes of three Pneumocystis species. We show that genes involved in host interaction evolve under positive selection. In the first place, we found strong evidence of episodic diversifying selection in Major surface glycoproteins (Msg). These proteins are located on the surface of Pneumocystis and are used for host attachment and probably for immune system evasion. Consistent with their function as antigens, most sites under diversifying selection in Msg code for residues with large relative surface accessibility areas. We also found evidence of positive selection in part of the cell machinery used to export Msg to the cell surface. Specifically, we found that genes participating in glycosylphosphatidylinositol (GPI) biosynthesis show an increased rate of nonsynonymous substitutions (dN) versus synonymous substitutions (dS). GPI is a molecule synthesized in the endoplasmic reticulum that is used to anchor proteins to membranes. We interpret the aforementioned findings as evidence of selective pressure exerted by the host immune system on Pneumocystis species, shaping the evolution of Msg and several proteins involved in GPI biosynthesis. We suggest that genome evolution in Pneumocystis is well described by the Red-Queen hypothesis whereby genes relevant for biotic interactions show accelerated rates of evolution.
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Affiliation(s)
- Luis Delaye
- Departamento de Ingeniería Genética, CINVESTAV Irapuato, Guanajuato, México
| | - Susana Ruiz-Ruiz
- Fundación para el Fomento de la Investigación Sanitaria y Biomédica de la Comunitat Valenciana (FISABIO)-Salud Pública, València, Spain
| | - Enrique Calderon
- Instituto de Biomedicina de Sevilla, Hospital Universitario Virgen del Rocío/Consejo Superior de Investigaciones Científicas/Universidad de Sevilla.,Investigación Biomédica en Red de Epidemiología y Salud Pública (CIBERESP), Madrid, Spain
| | - Sonia Tarazona
- Centro de Investigacion Principe Felipe, València, Spain.,Departamento de Estadística e Investigación Operativa Aplicadas y Calidad, Universitat Politècnica de València, Spain
| | - Ana Conesa
- Centro de Investigacion Principe Felipe, València, Spain.,Microbiology and Cell Science, University of Florida
| | - Andrés Moya
- Fundación para el Fomento de la Investigación Sanitaria y Biomédica de la Comunitat Valenciana (FISABIO)-Salud Pública, València, Spain.,Institute for Integrative Systems Biology, Universitat de València, Spain
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2
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Daub JT, Moretti S, Davydov II, Excoffier L, Robinson-Rechavi M. Detection of Pathways Affected by Positive Selection in Primate Lineages Ancestral to Humans. Mol Biol Evol 2017; 34:1391-1402. [PMID: 28333345 PMCID: PMC5435107 DOI: 10.1093/molbev/msx083] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Gene set enrichment approaches have been increasingly successful in finding signals of recent polygenic selection in the human genome. In this study, we aim at detecting biological pathways affected by positive selection in more ancient human evolutionary history. Focusing on four branches of the primate tree that lead to modern humans, we tested all available protein coding gene trees of the Primates clade for signals of adaptation in these branches, using the likelihood-based branch site test of positive selection. The results of these locus-specific tests were then used as input for a gene set enrichment test, where whole pathways are globally scored for a signal of positive selection, instead of focusing only on outlier "significant" genes. We identified signals of positive selection in several pathways that are mainly involved in immune response, sensory perception, metabolism, and energy production. These pathway-level results are highly significant, even though there is no functional enrichment when only focusing on top scoring genes. Interestingly, several gene sets are found significant at multiple levels in the phylogeny, but different genes are responsible for the selection signal in the different branches. This suggests that the same function has been optimized in different ways at different times in primate evolution.
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Affiliation(s)
- J T Daub
- CMPG, Institute of Ecology and Evolution, University of Berne, Berne, Switzerland.,SIB Swiss Institute of Bioinformatics, Lausanne, Switzerland
| | - S Moretti
- SIB Swiss Institute of Bioinformatics, Lausanne, Switzerland.,Department of Ecology and Evolution, University of Lausanne, Lausanne, Switzerland
| | - I I Davydov
- SIB Swiss Institute of Bioinformatics, Lausanne, Switzerland.,Department of Ecology and Evolution, University of Lausanne, Lausanne, Switzerland
| | - L Excoffier
- CMPG, Institute of Ecology and Evolution, University of Berne, Berne, Switzerland.,SIB Swiss Institute of Bioinformatics, Lausanne, Switzerland
| | - M Robinson-Rechavi
- SIB Swiss Institute of Bioinformatics, Lausanne, Switzerland.,Department of Ecology and Evolution, University of Lausanne, Lausanne, Switzerland
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Vedanayagam JP, Garrigan D. The effects of natural selection across molecular pathways in Drosophila melanogaster. BMC Evol Biol 2015; 15:203. [PMID: 26391223 PMCID: PMC4578789 DOI: 10.1186/s12862-015-0472-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Accepted: 08/30/2015] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Whole-genome RNA interference post-transcriptional silencing (RNAi) is a widely used method for studying the phenotypic effects of knocking down individual genes. In this study, we use a population genomic approach to characterize the rate of evolution for proteins affecting 26 RNAi knockdown phenotypes in Drosophila melanogaster. RESULTS We find that only two of the 26 RNAi knockdown phenotypes are enriched for rapidly evolving proteins: innate immunity and regulation of Hedgehog signaling. Among all genes associated with an RNAi knockdown phenotype, we note examples in which the adaptively evolving proteins play a well-defined role in a given molecular pathway. However, most adaptively evolving proteins are found to perform more general cellular functions. When RNAi phenotypes are grouped into categories according to cellular function, we find that genes involved in the greatest number of phenotypic categories are also significantly more likely to have a history of rapid protein evolution. CONCLUSIONS We show that genes that have been demonstrated to have a measurable effect on multiple molecular phenotypes show higher rates of protein evolution than genes having an effect on a single category of phenotype. Defining pleiotropy in this way yields very different results than previous studies that define pleiotropy by the number of physical interactions, which show highly connected proteins tend to evolve more slowly than lowly connected proteins. We suggest that a high degree of pleiotropy may increase the likelihood of compensatory substitution, consistent with modern theoretical work on adaptation.
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Affiliation(s)
| | - Daniel Garrigan
- Department of Biology, University of Rochester, Rochester, New York, 14627, USA.
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Santpere G, Carnero-Montoro E, Petit N, Serra F, Hvilsom C, Rambla J, Heredia-Genestar JM, Halligan DL, Dopazo H, Navarro A, Bosch E. Analysis of Five Gene Sets in Chimpanzees Suggests Decoupling between the Action of Selection on Protein-Coding and on Noncoding Elements. Genome Biol Evol 2015; 7:1490-505. [PMID: 25977458 PMCID: PMC4494068 DOI: 10.1093/gbe/evv082] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
We set out to investigate potential differences and similarities between the selective forces acting upon the coding and noncoding regions of five different sets of genes defined according to functional and evolutionary criteria: 1) two reference gene sets presenting accelerated and slow rates of protein evolution (the Complement and Actin pathways); 2) a set of genes with evidence of accelerated evolution in at least one of their introns; and 3) two gene sets related to neurological function (Parkinson’s and Alzheimer’s diseases). To that effect, we combine human–chimpanzee divergence patterns with polymorphism data obtained from target resequencing 20 central chimpanzees, our closest relatives with largest long-term effective population size. By using the distribution of fitness effect-alpha extension of the McDonald–Kreitman test, we reproduce inferences of rates of evolution previously based only on divergence data on both coding and intronic sequences and also obtain inferences for other classes of genomic elements (untranslated regions, promoters, and conserved noncoding sequences). Our results suggest that 1) the distribution of fitness effect-alpha method successfully helps distinguishing different scenarios of accelerated divergence (adaptation or relaxed selective constraints) and 2) the adaptive history of coding and noncoding sequences within the gene sets analyzed is decoupled.
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Affiliation(s)
- Gabriel Santpere
- Departament de Ciències Experimentals i la Salut, Institute of Evolutionary Biology (UPF-CSIC), Universitat Pompeu Fabra, PRBB, Barcelona, Spain
| | - Elena Carnero-Montoro
- Departament de Ciències Experimentals i la Salut, Institute of Evolutionary Biology (UPF-CSIC), Universitat Pompeu Fabra, PRBB, Barcelona, Spain
| | - Natalia Petit
- Departament de Ciències Experimentals i la Salut, Institute of Evolutionary Biology (UPF-CSIC), Universitat Pompeu Fabra, PRBB, Barcelona, Spain
| | - François Serra
- Structural Genomics Team, Genome Biology Group, Centre Nacional d'Anàlisi Genòmica (CNAG), Barcelona, Spain
| | | | - Jordi Rambla
- Departament de Ciències Experimentals i la Salut, Institute of Evolutionary Biology (UPF-CSIC), Universitat Pompeu Fabra, PRBB, Barcelona, Spain
| | - Jose Maria Heredia-Genestar
- Departament de Ciències Experimentals i la Salut, Institute of Evolutionary Biology (UPF-CSIC), Universitat Pompeu Fabra, PRBB, Barcelona, Spain
| | - Daniel L Halligan
- Institute of Evolutionary Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Hernan Dopazo
- Biomedical Genomics & Evolution Laboratory, Departamento de Ecología, Genética y Evolución, IEGEBA (CONICET-UBA), Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Argentina
| | - Arcadi Navarro
- Departament de Ciències Experimentals i la Salut, Institute of Evolutionary Biology (UPF-CSIC), Universitat Pompeu Fabra, PRBB, Barcelona, Spain National Institute for Bioinformatics (INB), PRBB, Barcelona, Spain Institució Catalana de Recerca i Estudis Avançats (ICREA), PRBB, Barcelona, Spain Center for Genomic Regulation (CRG), PRBB, Barcelona, Spain
| | - Elena Bosch
- Departament de Ciències Experimentals i la Salut, Institute of Evolutionary Biology (UPF-CSIC), Universitat Pompeu Fabra, PRBB, Barcelona, Spain
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Price DC, Fonseca DM. Genetic divergence between populations of feral and domestic forms of a mosquito disease vector assessed by transcriptomics. PeerJ 2015; 3:e807. [PMID: 25755934 PMCID: PMC4349049 DOI: 10.7717/peerj.807] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2014] [Accepted: 02/09/2015] [Indexed: 11/25/2022] Open
Abstract
Culex pipiens, an invasive mosquito and vector of West Nile virus in the US, has two morphologically indistinguishable forms that differ dramatically in behavior and physiology. Cx. pipiens form pipiens is primarily a bird-feeding temperate mosquito, while the sub-tropical Cx. pipiens form molestus thrives in sewers and feeds on mammals. Because the feral form can diapause during the cold winters but the domestic form cannot, the two Cx. pipiens forms are allopatric in northern Europe and, although viable, hybrids are rare. Cx. pipiens form molestus has spread across all inhabited continents and hybrids of the two forms are common in the US. Here we elucidate the genes and gene families with the greatest divergence rates between these phenotypically diverged mosquito populations, and discuss them in light of their potential biological and ecological effects. After generating and assembling novel transcriptome data for each population, we performed pairwise tests for nonsynonymous divergence (Ka) of homologous coding sequences and examined gene ontology terms that were statistically over-represented in those sequences with the greatest divergence rates. We identified genes involved in digestion (serine endopeptidases), innate immunity (fibrinogens and α-macroglobulins), hemostasis (D7 salivary proteins), olfaction (odorant binding proteins) and chitin binding (peritrophic matrix proteins). By examining molecular divergence between closely related yet phenotypically divergent forms of the same species, our results provide insights into the identity of rapidly-evolving genes between incipient species. Additionally, we found that families of signal transducers, ATP synthases and transcription regulators remained identical at the amino acid level, thus constituting conserved components of the Cx. pipiens proteome. We provide a reference with which to gauge the divergence reported in this analysis by performing a comparison of transcriptome sequences from conspecific (yet allopatric) populations of another member of the Cx. pipiens complex, Cx. quinquefasciatus.
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Affiliation(s)
- Dana C Price
- Department of Entomology, Rutgers University , New Brunswick, NJ , USA
| | - Dina M Fonseca
- Department of Entomology, Rutgers University , New Brunswick, NJ , USA
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Mensch J, Serra F, Lavagnino NJ, Dopazo H, Hasson E. Positive selection in nucleoporins challenges constraints on early expressed genes in Drosophila development. Genome Biol Evol 2014; 5:2231-41. [PMID: 24171912 PMCID: PMC3845637 DOI: 10.1093/gbe/evt156] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Developmental conservation among related species is a common generalization known as von Baer’s third law and implies that early stages of development are the most refractory to change. The “hourglass model” is an alternative view that proposes that middle stages are the most constrained during development. To investigate this issue, we undertook a genomic approach and provide insights into how natural selection operates on genes expressed during the first 24 h of Drosophila ontogeny in the six species of the melanogaster group for which whole genome sequences are available. Having studied the rate of evolution of more than 2,000 developmental genes, our results showed differential selective pressures at different moments of embryogenesis. In many Drosophila species, early zygotic genes evolved slower than maternal genes indicating that mid-embryogenesis is the stage most refractory to evolutionary change. Interestingly, positively selected genes were found in all embryonic stages even during the period with the highest developmental constraint, emphasizing that positive selection and negative selection are not mutually exclusive as it is often mistakenly considered. Among the fastest evolving genes, we identified a network of nucleoporins (Nups) as part of the maternal transcriptome. Specifically, the acceleration of Nups was driven by positive selection only in the more recently diverged species. Because many Nups are involved in hybrid incompatibilities between species of the Drosophila melanogaster subgroup, our results link rapid evolution of early developmental genes with reproductive isolation. In summary, our study revealed that even within functional groups of genes evolving under strong negative selection many positively selected genes could be recognized. Understanding these exceptions to the broad evolutionary conservation of early expressed developmental genes can shed light into relevant processes driving the evolution of species divergence.
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Affiliation(s)
- Julián Mensch
- Departamento de Ecología, Genética y Evolución-IEGEBA (CONICET-UBA), Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina
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7
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Garcia-Alonso L, Jiménez-Almazán J, Carbonell-Caballero J, Vela-Boza A, Santoyo-López J, Antiñolo G, Dopazo J. The role of the interactome in the maintenance of deleterious variability in human populations. Mol Syst Biol 2014; 10:752. [PMID: 25261458 PMCID: PMC4299661 DOI: 10.15252/msb.20145222] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2014] [Revised: 08/23/2014] [Accepted: 08/28/2014] [Indexed: 12/25/2022] Open
Abstract
Recent genomic projects have revealed the existence of an unexpectedly large amount of deleterious variability in the human genome. Several hypotheses have been proposed to explain such an apparently high mutational load. However, the mechanisms by which deleterious mutations in some genes cause a pathological effect but are apparently innocuous in other genes remain largely unknown. This study searched for deleterious variants in the 1,000 genomes populations, as well as in a newly sequenced population of 252 healthy Spanish individuals. In addition, variants causative of monogenic diseases and somatic variants from 41 chronic lymphocytic leukaemia patients were analysed. The deleterious variants found were analysed in the context of the interactome to understand the role of network topology in the maintenance of the observed mutational load. Our results suggest that one of the mechanisms whereby the effect of these deleterious variants on the phenotype is suppressed could be related to the configuration of the protein interaction network. Most of the deleterious variants observed in healthy individuals are concentrated in peripheral regions of the interactome, in combinations that preserve their connectivity, and have a marginal effect on interactome integrity. On the contrary, likely pathogenic cancer somatic deleterious variants tend to occur in internal regions of the interactome, often with associated structural consequences. Finally, variants causative of monogenic diseases seem to occupy an intermediate position. Our observations suggest that the real pathological potential of a variant might be more a systems property rather than an intrinsic property of individual proteins.
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Affiliation(s)
- Luz Garcia-Alonso
- Computational Genomics Department, Centro de Investigación Príncipe Felipe (CIPF), Valencia, Spain
| | - Jorge Jiménez-Almazán
- Computational Genomics Department, Centro de Investigación Príncipe Felipe (CIPF), Valencia, Spain Bioinformatics of Rare Diseases (BIER), CIBER de Enfermedades Raras (CIBERER), Valencia, Spain
| | - Jose Carbonell-Caballero
- Computational Genomics Department, Centro de Investigación Príncipe Felipe (CIPF), Valencia, Spain
| | - Alicia Vela-Boza
- Medical Genome Project, Genomics and Bioinformatics Platform of Andalusia (GBPA), Seville, Spain
| | - Javier Santoyo-López
- Medical Genome Project, Genomics and Bioinformatics Platform of Andalusia (GBPA), Seville, Spain
| | - Guillermo Antiñolo
- Medical Genome Project, Genomics and Bioinformatics Platform of Andalusia (GBPA), Seville, Spain Department of Genetics, Reproduction and Fetal Medicine, Institute of Biomedicine of Seville, University Hospital Virgen del Rocio/Consejo Superior de Investigaciones Científicas/University of Seville, Seville, Spain Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Seville, Spain
| | - Joaquin Dopazo
- Computational Genomics Department, Centro de Investigación Príncipe Felipe (CIPF), Valencia, Spain Bioinformatics of Rare Diseases (BIER), CIBER de Enfermedades Raras (CIBERER), Valencia, Spain Medical Genome Project, Genomics and Bioinformatics Platform of Andalusia (GBPA), Seville, Spain Functional Genomics Node, (INB) at CIPF, Valencia, Spain
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Abstract
The rise of systems biology is intertwined with that of genomics, yet their primordial relationship to one another is ill-defined. We discuss how the growth of genomics provided a critical boost to the popularity of systems biology. We describe the parts of genomics that share common areas of interest with systems biology today in the areas of gene expression, network inference, chromatin state analysis, pathway analysis, personalized medicine, and upcoming areas of synergy as genomics continues to expand its scope across all biomedical fields.
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Affiliation(s)
- Ana Conesa
- Genomics of Gene Expression Lab, Centro de Investigaciones Príncipe Felipe, Valencia, Spain
| | - Ali Mortazavi
- Department of Developmental and Cell Biology, University of California, Irvine, CA 92697, USA
- Center for Complex Biological Systems, University of California, Irvine, CA 92697, USA
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9
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Lu B, Yang W, Dai Q, Fu J. Using genes as characters and a parsimony analysis to explore the phylogenetic position of turtles. PLoS One 2013; 8:e79348. [PMID: 24278129 PMCID: PMC3836853 DOI: 10.1371/journal.pone.0079348] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2013] [Accepted: 09/26/2013] [Indexed: 11/18/2022] Open
Abstract
The phylogenetic position of turtles within the vertebrate tree of life remains controversial. Conflicting conclusions from different studies are likely a consequence of systematic error in the tree construction process, rather than random error from small amounts of data. Using genomic data, we evaluate the phylogenetic position of turtles with both conventional concatenated data analysis and a "genes as characters" approach. Two datasets were constructed, one with seven species (human, opossum, zebra finch, chicken, green anole, Chinese pond turtle, and western clawed frog) and 4584 orthologous genes, and the second with four additional species (soft-shelled turtle, Nile crocodile, royal python, and tuatara) but only 1638 genes. Our concatenated data analysis strongly supported turtle as the sister-group to archosaurs (the archosaur hypothesis), similar to several recent genomic data based studies using similar methods. When using genes as characters and gene trees as character-state trees with equal weighting for each gene, however, our parsimony analysis suggested that turtles are possibly sister-group to diapsids, archosaurs, or lepidosaurs. None of these resolutions were strongly supported by bootstraps. Furthermore, our incongruence analysis clearly demonstrated that there is a large amount of inconsistency among genes and most of the conflict relates to the placement of turtles. We conclude that the uncertain placement of turtles is a reflection of the true state of nature. Concatenated data analysis of large and heterogeneous datasets likely suffers from systematic error and over-estimates of confidence as a consequence of a large number of characters. Using genes as characters offers an alternative for phylogenomic analysis. It has potential to reduce systematic error, such as data heterogeneity and long-branch attraction, and it can also avoid problems associated with computation time and model selection. Finally, treating genes as characters provides a convenient method for examining gene and genome evolution.
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Affiliation(s)
- Bin Lu
- Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, Sichuan, China
| | - Weizhao Yang
- Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, Sichuan, China
| | - Qiang Dai
- Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, Sichuan, China
| | - Jinzhong Fu
- Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, Sichuan, China
- Department of Integrative Biology, University of Guelph, Guelph, Ontario, Canada
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Carreira VP, Imberti MA, Mensch J, Fanara JJ. Gene-by-temperature interactions and candidate plasticity genes for morphological traits in Drosophila melanogaster. PLoS One 2013; 8:e70851. [PMID: 23936253 PMCID: PMC3728209 DOI: 10.1371/journal.pone.0070851] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2012] [Accepted: 06/26/2013] [Indexed: 01/06/2023] Open
Abstract
Understanding the genetic architecture of any quantitative trait requires identifying the genes involved in its expression in different environmental conditions. This goal can be achieved by mutagenesis screens in genetically tractable model organisms such as Drosophila melanogaster. Temperature during ontogenesis is an important environmental factor affecting development and phenotypic variation in holometabolous insects. In spite of the importance of phenotypic plasticity and genotype by environment interaction (GEI) for fitness related traits, its genetic basis has remained elusive. In this context, we analyzed five different adult morphological traits (face width, head width, thorax length, wing size and wing shape) in 42 co-isogenic single P-element insertional lines of Drosophila melanogaster raised at 17°C and 25°C. Our analyses showed that all lines differed from the control for at least one trait in males or females at either temperature. However, no line showed those differences for all traits in both sexes and temperatures simultaneously. In this sense, the most pleiotropic candidate genes were CG34460, Lsd-2 and Spn. Our analyses also revealed extensive genetic variation for all the characters mostly indicated by strong GEIs. Further, our results indicate that GEIs were predominantly explained by changes in ranking order in all cases suggesting that a moderate number of genes are involved in the expression of each character at both temperatures. Most lines displayed a plastic response for at least one trait in either sex. In this regard, P-element insertions affecting plasticity of a large number of traits were associated to the candidate genes Btk29A, CG43340, Drak and jim. Further studies will help to elucidate the relevance of these genes on the morphogenesis of different body structures in natural populations of D. melanogaster.
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Affiliation(s)
- Valeria Paula Carreira
- Departamento de Ecología, Genética y Evolución, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Instituto de Ecología, Genética y Evolución de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires, Argentina.
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