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Katoh TK, Chen JM, Yang JH, Zhang G, Wang L, Suwito A, Ak Meleng P, Toda MJ, Zhang YP, Gao JJ. Molecular phylogeny and species diversity of the genus Dichaetophora Duda and related taxa (Diptera: Drosophilidae). Mol Phylogenet Evol 2024; 201:108194. [PMID: 39276821 DOI: 10.1016/j.ympev.2024.108194] [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: 05/02/2024] [Revised: 07/09/2024] [Accepted: 09/07/2024] [Indexed: 09/17/2024]
Abstract
Our intensive surveys of wild drosophilids in East and Southeast Asia discovered a great species diversity (more than 100 putatively new species) of the genus Dichaetophora, which is currently comprised of 67 formally described species assigned into five species groups, i.e., agbo, tenuicauda, acutissima, sinensis and trilobita. In the present study, we delimited species from a huge amount of samples of Dichaetophora and allied taxa (the genus Mulgravea and the subgenus Dudaica of Drosophila) collected from a wide range of the Oriental and east Palearctic regions. We first sorted all specimens into morpho-species, and representative specimen(s) selected from each morpho-species were subjected to barcoding of COI (the cytochrome c oxidase subunit I gene) sequences. The applied ASAP (Assemble Species by Automatic Partitioning) analysis estimated a total of 166 to 168 MOTUs (molecular operational taxonomic units). Integrating this result with morphological evidence from re-examined, detailed structures of male terminalia, we recognized a total of 144 (109 new and 35 known) species in our sample. Out of them, 83 species representing the supraspecific taxa of Dichaetophora, Mulgravea and Dudaica were selected, along with 33 species from major genera and subgenera of Drosophila in the tribe Drosophilini, as in-group and four species from the tribe Colocasiomyini as out-group for phylogenetic reconstruction based on 12 nuclear gene markers. In the trees constructed by the maximum likelihood and Bayesian inference methods, the three focal taxa (i.e., Dichaetophora, Mulgravea and Dudaica) formed a clade provisionally called the "pan-Dichaetophora". Within this large clade, the agbo, tenuicauda, sinensis and trilobita groups of Dichaetophora, Mulgravea and Dudaica were recovered as monophyletic groups, but Dichaetophora and its acutissima group were regarded as paraphyletic. In addition, two clusters were recognized among ungrouped species of Dichaetophora. Thus, the present study has uncovered some issues concerning the taxonomy of the pan-Dichaetophora. Such issues will be addressed elsewhere in the phylogenetic reclassification of the pan-Dichaetophora, along with descriptions/redescriptions of a large number of new/known species delimited in the present study.
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Affiliation(s)
- Takehiro K Katoh
- Ministry of Education Key Laboratory of Transboundary Eco-security of Southwest China, Yunnan Key Laboratory of Plant Reproductive Adaptation and Evolutionary Ecology (Institute of Biodiversity), Yunnan University, Kunming, Yunnan 650091, China; State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Yunnan University, Kunming, Yunnan 650500, China.
| | - Ji-Min Chen
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Yunnan University, Kunming, Yunnan 650500, China.
| | - Jin-Hua Yang
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Yunnan University, Kunming, Yunnan 650500, China.
| | - Guang Zhang
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Yunnan University, Kunming, Yunnan 650500, China.
| | - Lu Wang
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Yunnan University, Kunming, Yunnan 650500, China.
| | - Awit Suwito
- Research Center for Biosystematics and Evolution - National Research and Innovation Agency (BRIN), Jl. Raya Jakarta-Bogor Km. 46, Cibinong 16911, West Java, Indonesia.
| | - Paulus Ak Meleng
- Research and Development Division, Forest Department Sarawak, KM10, Jalan Datuk Amar Kalong Ningkan, 93200 Kuching, Sarawak, Malaysia.
| | - Masanori J Toda
- Hokkaido University Museum, Hokkaido University, Nishi 8, Kita 10, Kita-ku, Sapporo 060-0810, Japan.
| | - Ya-Ping Zhang
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Yunnan University, Kunming, Yunnan 650500, China; State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Kunming, Yunnan 650223, China.
| | - Jian-Jun Gao
- Ministry of Education Key Laboratory of Transboundary Eco-security of Southwest China, Yunnan Key Laboratory of Plant Reproductive Adaptation and Evolutionary Ecology (Institute of Biodiversity), Yunnan University, Kunming, Yunnan 650091, China; State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Yunnan University, Kunming, Yunnan 650500, China.
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Bjornson S, Verbruggen H, Upham NS, Steenwyk JL. Reticulate evolution: Detection and utility in the phylogenomics era. Mol Phylogenet Evol 2024; 201:108197. [PMID: 39270765 DOI: 10.1016/j.ympev.2024.108197] [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: 05/12/2024] [Revised: 08/13/2024] [Accepted: 09/08/2024] [Indexed: 09/15/2024]
Abstract
Phylogenomics has enriched our understanding that the Tree of Life can have network-like or reticulate structures among some taxa and genes. Two non-vertical modes of evolution - hybridization/introgression and horizontal gene transfer - deviate from a strictly bifurcating tree model, causing non-treelike patterns. However, these reticulate processes can produce similar patterns to incomplete lineage sorting or recombination, potentially leading to ambiguity. Here, we present a brief overview of a phylogenomic workflow for inferring organismal histories and compare methods for distinguishing modes of reticulate evolution. We discuss how the timing of coalescent events can help disentangle introgression from incomplete lineage sorting and how horizontal gene transfer events can help determine the relative timing of speciation events. In doing so, we identify pitfalls of certain methods and discuss how to extend their utility across the Tree of Life. Workflows, methods, and future directions discussed herein underscore the need to embrace reticulate evolutionary patterns for understanding the timing and rates of evolutionary events, providing a clearer view of life's history.
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Affiliation(s)
- Saelin Bjornson
- School of BioSciences, University of Melbourne, Victoria, Australia
| | - Heroen Verbruggen
- School of BioSciences, University of Melbourne, Victoria, Australia; CIBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, InBIO Laboratório Associado, Campus de Vairão, Universidade do Porto, 4485-661 Vairão, Portugal
| | - Nathan S Upham
- School of Life Sciences, Arizona State University, Tempe, AZ, USA.
| | - Jacob L Steenwyk
- Howards Hughes Medical Institute and the Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA, USA.
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3
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Zhang L, Nonaka E, Higgie M, Egan S. How Important Is Variation in Extrinsic Reproductive Isolation to the Process of Speciation? Cold Spring Harb Perspect Biol 2024; 16:a041430. [PMID: 38503503 PMCID: PMC11529849 DOI: 10.1101/cshperspect.a041430] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/21/2024]
Abstract
The strength of reproductive isolation (RI) between two or more lineages during the process of speciation can vary by the ecological conditions. However, most speciation research has been limited to studying how ecologically dependent RI varies among a handful of broadly categorized environments. Very few studies consider the variability of RI and its effects on speciation at finer scales-that is, within each environment due to spatial or temporal environmental heterogeneity. Such variation in RI across time and/or space may inhibit speciation through leaky reproductive barriers or promote speciation by facilitating reinforcement. To investigate this overlooked aspect of speciation research, we conducted a literature review of existing studies of variation in RI in the field and then conducted individual-based simulations to examine how variation in hybrid fitness across time and space affects the degree of gene flow. Our simulations indicate that the presence of variation in hybrid fitness across space and time often leads to an increase in gene flow compared to scenarios where hybrid fitness remains static. This observation can be attributed to the convex relationship between the degree of gene flow and the strength of selection on hybrids. Our simulations also show that the effect of variation in RI on facilitating gene flow is most pronounced when RI, on average, is relatively low. This finding suggests that it could serve as an important mechanism to explain why the completion of speciation is often challenging. While direct empirical evidence documenting variation in extrinsic RI is limited, we contend that it is a prevalent yet underexplored phenomenon. We support this argument by proposing common scenarios in which RI is likely to exhibit variability and thus influence the process of speciation.
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Affiliation(s)
- Linyi Zhang
- Department of Biological Sciences, George Washington University, Washington, D.C. 20052, USA
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, Ontario M5S3B2, Canada
| | - Etsuko Nonaka
- Department of Agricultural Science, University of Helsinki 00170, Finland
- Station Linné, Förjestaden, Öland 00014, Sweden
| | - Megan Higgie
- College of Science & Engineering, James Cook University, Townsville City, Queensland 4814, Australia
| | - Scott Egan
- Department of BioSciences, Rice University, Houston, Texas 77005, USA
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4
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Lanfear R, Hahn MW. The Meaning and Measure of Concordance Factors in Phylogenomics. Mol Biol Evol 2024; 41:msae214. [PMID: 39418118 PMCID: PMC11532913 DOI: 10.1093/molbev/msae214] [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: 12/22/2023] [Revised: 09/25/2024] [Accepted: 10/04/2024] [Indexed: 10/19/2024] Open
Abstract
As phylogenomic datasets have grown in size, researchers have developed new ways to measure biological variation and to assess statistical support for specific branches. Larger datasets have more sites and loci and therefore less sampling variance. While we can more accurately measure the mean signal in these datasets, lower sampling variance is often reflected in uniformly high measures of branch support-such as the bootstrap and posterior probability-limiting their utility. Larger datasets have also revealed substantial biological variation in the topologies found across individual loci, such that the single species tree inferred by most phylogenetic methods represents a limited summary of the data for many purposes. In contrast to measures of statistical support, the degree of underlying topological variation among loci should be approximately constant regardless of the size of the dataset. "Concordance factors" (CFs) and similar statistics have therefore become increasingly important tools in phylogenetics. In this review, we explain why CFs should be thought of as descriptors of topological variation rather than as measures of statistical support, and argue that they provide important information about the predictive power of the species tree not contained in measures of support. We review a growing suite of statistics for measuring concordance, compare them in a common framework that reveals their interrelationships, and demonstrate how to calculate them using an example from birds. We also discuss how measures of topological variation might change in the future as we move beyond estimating a single "tree of life" toward estimating the myriad evolutionary histories underlying genomic variation.
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Affiliation(s)
- Robert Lanfear
- Ecology and Evolution, Research School of Biology, Australian National University, Canberra, Australia
| | - Matthew W Hahn
- Department of Biology, Indiana University, Bloomington, IN, USA
- Department of Computer Science, Indiana University, Bloomington, IN, USA
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5
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Lv FH, Wang DF, Zhao SY, Lv XY, Sun W, Nielsen R, Li MH. Deep Ancestral Introgressions between Ovine Species Shape Sheep Genomes via Argali-Mediated Gene Flow. Mol Biol Evol 2024; 41:msae212. [PMID: 39404100 PMCID: PMC11542629 DOI: 10.1093/molbev/msae212] [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: 03/10/2024] [Revised: 09/12/2024] [Accepted: 10/04/2024] [Indexed: 11/08/2024] Open
Abstract
Previous studies revealed extensive genetic introgression between Ovis species, which affects genetic adaptation and morphological traits. However, the exact evolutionary scenarios underlying the hybridization between sheep and allopatric wild relatives remain unknown. To address this problem, we here integrate the reference genomes of several ovine and caprine species: domestic sheep, argali, bighorn sheep, snow sheep, and domestic goats. Additionally, we use 856 whole genomes representing 169 domestic sheep populations and their six wild relatives: Asiatic mouflon, urial, argali, snow sheep, thinhorn sheep, and bighorn sheep. We implement a comprehensive set of analyses to test introgression among these species. We infer that the argali lineage originated ∼3.08 to 3.35 Mya and hybridized with the ancestor of Pachyceriforms (e.g. bighorn sheep and snow sheep) at ∼1.56 Mya. Previous studies showed apparent introgression from North American Pachyceriforms into the Bashibai sheep, a Chinese native sheep breed, despite of their wide geographic separation. We show here that, in fact, the apparent introgression from the Pachyceriforms into Bashibai can be explained by the old introgression from Pachyceriforms into argali and subsequent recent introgression from argali into Bashibai. Our results illustrate the challenges of estimating complex introgression histories and provide an example of how indirect and direct introgression can be distinguished.
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Affiliation(s)
- Feng-Hua Lv
- Frontiers Science Center for Molecular Design Breeding (MOE), State Key Laboratory of Animal Biotech Breeding, College of Animal Science and Technology, China Agricultural University, Beijing 100193, China
| | - Dong-Feng Wang
- CAS Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences (CAS), Beijing, China
- College of Life Sciences, University of Chinese Academy of Sciences (UCAS), Beijing, China
| | - Si-Yi Zhao
- Frontiers Science Center for Molecular Design Breeding (MOE), State Key Laboratory of Animal Biotech Breeding, College of Animal Science and Technology, China Agricultural University, Beijing 100193, China
| | - Xiao-Yang Lv
- International Joint Research Laboratory, Universities of Jiangsu Province of China for Domestic Animal Germplasm Resources and Genetic Improvement, Yangzhou 225001, China
| | - Wei Sun
- International Joint Research Laboratory, Universities of Jiangsu Province of China for Domestic Animal Germplasm Resources and Genetic Improvement, Yangzhou 225001, China
| | - Rasmus Nielsen
- Department of Integrative Biology, University of California at Berkeley, Berkeley, CA 94720, USA
- Department of Statistics, UC Berkeley, Berkeley, CA 94707, USA
- Globe Institute, University of Copenhagen, Copenhagen 1350, Denmark
| | - Meng-Hua Li
- Frontiers Science Center for Molecular Design Breeding (MOE), State Key Laboratory of Animal Biotech Breeding, College of Animal Science and Technology, China Agricultural University, Beijing 100193, China
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6
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Koppetsch T, Malinsky M, Matschiner M. Towards Reliable Detection of Introgression in the Presence of Among-Species Rate Variation. Syst Biol 2024; 73:769-788. [PMID: 38912803 DOI: 10.1093/sysbio/syae028] [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: 05/23/2023] [Revised: 05/23/2024] [Accepted: 06/19/2024] [Indexed: 06/25/2024] Open
Abstract
The role of interspecific hybridization has recently seen increasing attention, especially in the context of diversification dynamics. Genomic research has now made it abundantly clear that both hybridization and introgression-the exchange of genetic material through hybridization and backcrossing-are far more common than previously thought. Besides cases of ongoing or recent genetic exchange between taxa, an increasing number of studies report "ancient introgression"- referring to results of hybridization that took place in the distant past. However, it is not clear whether commonly used methods for the detection of introgression are applicable to such old systems, given that most of these methods were originally developed for analyses at the level of populations and recently diverged species, affected by recent or ongoing genetic exchange. In particular, the assumption of constant evolutionary rates, which is implicit in many commonly used approaches, is more likely to be violated as evolutionary divergence increases. To test the limitations of introgression detection methods when being applied to old systems, we simulated thousands of genomic datasets under a wide range of settings, with varying degrees of among-species rate variation and introgression. Using these simulated datasets, we showed that some commonly applied statistical methods, including the D-statistic and certain tests based on sets of local phylogenetic trees, can produce false-positive signals of introgression between divergent taxa that have different rates of evolution. These misleading signals are caused by the presence of homoplasies occurring at different rates in different lineages. To distinguish between the patterns caused by rate variation and genuine introgression, we developed a new test that is based on the expected clustering of introgressed sites along the genome and implemented this test in the program Dsuite.
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Affiliation(s)
- Thore Koppetsch
- Natural History Museum, University of Oslo, 0318 Oslo, Norway
| | - Milan Malinsky
- Institute of Ecology and Evolution, Department of Biology, University of Bern, 3012 Bern, Switzerland
- Department of Fish Ecology and Evolution, EAWAG Swiss Federal Institute of Aquatic Science and Technology, Kastanienbaum, Switzerland
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7
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Li J, Ai Q, Xie S, Huang C, Qiu F, Fu C, Zhao M, Fu J, Wu H. Contrast and Genomic Characterisation of Ancient and Recent Interspecific Introgression Between Deeply Diverged Moustache Toads (Leptobrachium). Mol Ecol 2024:e17569. [PMID: 39465507 DOI: 10.1111/mec.17569] [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: 07/04/2024] [Revised: 10/03/2024] [Accepted: 10/14/2024] [Indexed: 10/29/2024]
Abstract
Recent genomic analyses have provided new insights into the process of interspecific introgression and its consequences on species evolution. Most recent studies, however, focused on hybridization between recently radiated species, with few examining the genomic outcomes of ancient hybridization across deeply diverged species. Using whole genome data of moustache toads (Leptobrachium), we identified signals of three hybridization events among nine species that diverged at the Eocene. An ancient introgression from L. leishanense to the ancestral branch (C1) of L. liui introduced adaptive variants. The highly introgressed regions include genes with important functions in odorant detection and immune responses. These genes are preserved in all three descendent populations of L. liui_C1, and these regions likely have been positively selected over a long filtering process. A recent introgression occurred from L. huashen to L. tengchongense, with the introgressed regions being mostly neutral. Furthermore, one F1 hybrid individual was detected between sympatric L. ailaonicum and L. promustache. The signals of introgression largely disappeared after removing the hybrid individual, indicating an occasional hybridization but minimal introgression. Further examination of highly divergent but low introgressed genomic regions revealed both pre-mating isolation and genetic incompatibility as potential mechanisms of resisting introgression and maintaining species boundaries. Additionally, no large X-effect was found in these introgression events. Hybridization between deeply diverged amphibian species may be common, but detectable introgressions are likely less so, with recent introgression being mostly neutral and the rare ancient one potentially adaptive. Our findings complement recent genomic work, and together they provide a better understanding of the genomic characteristics of interspecific introgression and its significance in species adaptation and evolution.
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Affiliation(s)
- Jun Li
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, Hubei, People's Republic of China
| | - Qingbo Ai
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, Hubei, People's Republic of China
| | - Siyu Xie
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, Hubei, People's Republic of China
| | - Chunhua Huang
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, Hubei, People's Republic of China
| | - Fuyuan Qiu
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, Hubei, People's Republic of China
| | - Chao Fu
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, Hubei, People's Republic of China
| | - Mian Zhao
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, Hubei, People's Republic of China
| | - Jinzhong Fu
- Department of Integrative Biology, University of Guelph, Guelph, Ontario, Canada
| | - Hua Wu
- Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, Hubei, People's Republic of China
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8
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Li M, Chen DS, Junker IP, Szorenyi FI, Chen GH, Berger AJ, Comeault AA, Matute DR, Ding Y. Ancestral neural circuits potentiate the origin of a female sexual behavior in Drosophila. Nat Commun 2024; 15:9210. [PMID: 39468043 PMCID: PMC11519493 DOI: 10.1038/s41467-024-53610-w] [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: 12/13/2023] [Accepted: 10/14/2024] [Indexed: 10/30/2024] Open
Abstract
Courtship interactions are remarkably diverse in form and complexity among species. How neural circuits evolve to encode new behaviors that are functionally integrated into these dynamic social interactions is unknown. Here we report a recently originated female sexual behavior in the island endemic Drosophila species D. santomea, where females signal receptivity to male courtship songs by spreading their wings, which in turn promotes prolonged songs in courting males. Copulation success depends on this female signal and correlates with males' ability to adjust his singing in such a social feedback loop. Functional comparison of sexual circuitry across species suggests that a pair of descending neurons, which integrates male song stimuli and female internal state to control a conserved female abdominal behavior, drives wing spreading in D. santomea. This co-option occurred through the refinement of a pre-existing, plastic circuit that can be optogenetically activated in an outgroup species. Combined, our results show that the ancestral potential of a socially-tuned key circuit node to engage the wing motor circuit facilitates the expression of a new female behavior in appropriate sensory and motivational contexts. More broadly, our work provides insights into the evolution of social behaviors, particularly female behaviors, and the underlying neural mechanisms.
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Affiliation(s)
- Minhao Li
- Department of Biology, University of Pennsylvania, Philadelphia, PA, USA
| | - Dawn S Chen
- Department of Biology, University of Pennsylvania, Philadelphia, PA, USA
| | - Ian P Junker
- Department of Biology, University of Pennsylvania, Philadelphia, PA, USA
| | | | - Guan Hao Chen
- Department of Biology, University of Pennsylvania, Philadelphia, PA, USA
| | - Arnold J Berger
- Department of Biology, University of Pennsylvania, Philadelphia, PA, USA
| | - Aaron A Comeault
- Department of Biology, University of North Carolina, Chapel Hill, NC, USA
- School of Environmental and Natural Sciences, Bangor University, Bangor, UK
| | - Daniel R Matute
- Department of Biology, University of North Carolina, Chapel Hill, NC, USA
| | - Yun Ding
- Department of Biology, University of Pennsylvania, Philadelphia, PA, USA.
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9
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Myers EA, Rautsaw RM, Borja M, Jones J, Grünwald CI, Holding ML, Grazziotin FG, 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; 73:722-741. [PMID: 38695290 DOI: 10.1093/sysbio/syae018] [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: 05/10/2023] [Revised: 04/01/2024] [Accepted: 04/30/2024] [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 those 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 35010, Mexico
| | - 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 G Grazziotin
- Laboratório de Coleções Zoológicas, Instituto Butantan, Avenida Vital Brasil, São Paulo, 05503-900, Brazil
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10
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Luo Y, Talross GJS, Carlson JR. Function and evolution of Ir52 receptors in mate detection in Drosophila. Curr Biol 2024:S0960-9822(24)01355-1. [PMID: 39471807 DOI: 10.1016/j.cub.2024.10.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2024] [Revised: 08/11/2024] [Accepted: 10/01/2024] [Indexed: 11/01/2024]
Abstract
Identifying a suitable mating partner is an ancient and critical biological problem. How a fruit fly distinguishes a fly of the same species from flies of innumerable related species remains unclear. We analyze the Ir52 receptors, expressed in taste neurons on the fly legs and encoded by a cluster of genes. We find that the cluster shows dynamic evolution, rapidly expanding and contracting over evolutionary time. We develop a novel in vivo expression system and find that Ir52 receptors respond differently to pheromone extracts of different fly species. The receptors are activated by some compounds and inhibited by others, with different receptors showing distinct response profiles. Circuit mapping shows that Ir52 neurons are pre-synaptic to sexually dimorphic neurons that overlap with neurons acting in courtship behavior. Our results support a model in which Ir52 receptors detect information about the species of a potential mating partner.
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Affiliation(s)
- Yichen Luo
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT 06511, USA; Interdepartmental Neuroscience Program, Yale University, New Haven, CT 06511, USA
| | - Gaëlle J S Talross
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT 06511, USA
| | - John R Carlson
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT 06511, USA; Interdepartmental Neuroscience Program, Yale University, New Haven, CT 06511, USA.
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11
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Elmer KR, Clobert J. Dollo's law of irreversibility in the post-genomic age. Trends Ecol Evol 2024:S0169-5347(24)00249-0. [PMID: 39443236 DOI: 10.1016/j.tree.2024.09.010] [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: 12/21/2023] [Revised: 09/03/2024] [Accepted: 09/27/2024] [Indexed: 10/25/2024]
Abstract
Dollo's law of irreversibility argues that evolution cannot revert to earlier states. It has remained controversial ever since its inception in the 19th century. Enabled by advances in phylogenomics and functional genomics, recent studies show that there are very likely some cases of 'breaking Dollo's law'. As post-genomic research grows from showing patterns to revealing processes, new emphasis is needed on the molecular mechanisms by which Dollo's law might be broken. Shifting the argument from 'if it happened' to 'how it happened' will provide richer understanding of organismal and evolutionary biology. Motivated by case studies and novel avenues to test trait loss and regain, we outline a set of alternative hypotheses to be evaluated and what the outcomes tell us about evolution.
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Affiliation(s)
- Kathryn R Elmer
- School of Biodiversity, One Health and Veterinary Medicine, College of Medical, Veterinary, and Life Sciences, University of Glasgow, Glasgow, G12 8QQ, UK; Station d'Ecologie Théorique et Expérimentale - CNRS, Moulis, 09200, France.
| | - Jean Clobert
- Station d'Ecologie Théorique et Expérimentale - CNRS, Moulis, 09200, France
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12
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Peckenpaugh B, Moyle LC. Females drive postmating reproductive trait evolution across Drosophila species, but not via remating rate. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.10.15.618555. [PMID: 39464019 PMCID: PMC11507895 DOI: 10.1101/2024.10.15.618555] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/29/2024]
Abstract
While traits that contribute to premating sexual interactions are known to be wildly diverse, much less is known about the diversity of postmating (especially female) reproductive traits and the mechanisms shaping this diversity. To assess the rate, pattern, and potential drivers of postmating reproductive trait evolution, we analyzed male and female traits across up to 30 Drosophila species within a phylogenetic comparative framework. In addition to postmating reproductive morphology (e.g., sperm length, reproductive tract length and mass), we also quantified mating behaviors including female remating rate-a common proxy for the strength of postmating sexual selection. We found evidence for strong coevolution between male and female postmating traits (specifically sperm length and sperm storage organ size). However, remating rate was not associated with the rate of evolution or exaggeration of either male or female postmating reproductive morphology, once phylogenetic relatedness was accounted for. We infer that female-mediated and intersexual selection predominantly drive the evolution of our postmating morphological traits, including via divergent male and female interests in controlling paternity. In comparison, remating rate has a complex and likely secondary role in shaping this evolution, in part because this trait can be both a driver and a product of postmating selection.
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Affiliation(s)
| | - Leonie C Moyle
- Department of Biology, Indiana University, Bloomington, Indiana 47405
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13
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Uckele KA, Vargas OM, Kay KM. Prezygotic barriers effectively limit hybridization in a rapid evolutionary radiation. THE NEW PHYTOLOGIST 2024. [PMID: 39400313 DOI: 10.1111/nph.20187] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2024] [Accepted: 09/22/2024] [Indexed: 10/15/2024]
Abstract
Hybridization is increasingly recognized as an important evolutionary process across the tree of life. In many clades, phylogenomic approaches have permitted unparalleled insight into the extent and frequency of hybridization. However, we continue to lack a deep understanding of the factors that limit and shape patterns of hybridization, especially in evolutionary radiations. In this study, we characterized patterns of introgression across Costus (Costaceae), a young evolutionary radiation of tropical understory plants that maintain widespread interfertility despite exhibiting strong prezygotic reproductive isolation. We analyzed a phylogenomic dataset of 756 genes from 54 Costus species using multiple complementary approaches - D-statistics, gene-tree-based tests, and phylogenetic network analyses - to detect and characterize introgression events throughout the evolutionary history of the radiation. Our results identified a moderate number of introgression events, including a particularly ancient, well-supported event spanning one of the deepest divergences in the clade. Most introgression events occurred between taxa or ancestral lineages that shared the same pollination syndrome (bee-pollinated or hummingbird-pollinated). These findings suggest that prezygotic barriers, including pollinator specialization, have been key to the balance between introgression and reproductive isolation in Costus.
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Affiliation(s)
- Kathryn A Uckele
- Department of Ecology and Evolutionary Biology, University of California, Santa Cruz, CA, 95060, USA
| | - Oscar M Vargas
- Department of Biological Sciences, California State Polytechnic University, Humboldt, Arcata, CA, 95521, USA
| | - Kathleen M Kay
- Department of Ecology and Evolutionary Biology, University of California, Santa Cruz, CA, 95060, USA
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14
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Monier M, Lorenzi JN, Narasimha S, Borne F, Contremoulins V, Mevel L, Petit R, El Hachem Y, Graner F, Courtier-Orgogozo V. Adhesive and mechanical properties of the glue produced by 25 Drosophila species. Sci Rep 2024; 14:23249. [PMID: 39370426 PMCID: PMC11456580 DOI: 10.1038/s41598-024-74358-9] [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: 05/09/2024] [Accepted: 09/25/2024] [Indexed: 10/08/2024] Open
Abstract
Drosophila glue, a bioadhesive produced by fly larvae to attach themselves to a substrate for several days, has recently gained attention for its peculiar adhesive and mechanical properties. Although Drosophila glue production was described more than 50 years ago, a general survey of the adhesive and mechanical properties of this proteinaceous gel across Drosophila species is lacking. To measure adhesion, we present here a protocol that is robust to variations in protocol parameters, pupal age and calculation methods. We find that the glue, which covers the entire pupal surface, increases the animal rigidity and plasticity when bound to a glass slide. Our survey of pupal adhesion in 25 Drosophilidae species reveals a wide range of phenotypes, from species that produce no or little glue and adhere little, to species that produce high amounts of glue and adhere strongly. One species, D. hydei, stands out from the rest and emerges as a promising model for the development of future bioadhesives, as it has the highest detachment force per glue area and produces relatively large amounts of glue relative to its size. We also observe that species that invest more in glue tend to live in more windy and less rainy climates, suggesting that differences in pupal adhesion properties across species are shaped by ecological factors. Our present survey provides a basis for future biomimetic studies based on Drosophila glue.
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Affiliation(s)
- Manon Monier
- Université Paris Cité, CNRS, Institut Jacques Monod, 75005, Paris, France
| | - Jean-Noël Lorenzi
- Université Paris Cité, CNRS, Institut Jacques Monod, 75005, Paris, France
- SMILE Group, Center for Interdisciplinary Research in Biology (CIRB), Collège de France, 75006, Paris, France
| | - Sunitha Narasimha
- Université Paris Cité, CNRS, Institut Jacques Monod, 75005, Paris, France
| | - Flora Borne
- Université Paris Cité, CNRS, Institut Jacques Monod, 75005, Paris, France
- Department of Biological Sciences, Columbia University, New York City, NY, USA
| | - Vincent Contremoulins
- Université Paris Cité, CNRS, Institut Jacques Monod, 75005, Paris, France
- Inserm, B3OA, 75010, Paris, France
| | - Louis Mevel
- Université Paris Cité, CNRS, Institut Jacques Monod, 75005, Paris, France
| | - Romane Petit
- Université Paris Cité, CNRS, Institut Jacques Monod, 75005, Paris, France
| | - Youssef El Hachem
- Université Paris Cité, CNRS, Institut Jacques Monod, 75005, Paris, France
| | - François Graner
- Université Paris Cité, CNRS, Matière et Systèmes Complexes, 75013, Paris, France.
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15
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Bessa MH, Gottschalk MS, Robe LJ. Whole genome phylogenomics helps to resolve the phylogenetic position of the Zygothrica genus group (Diptera, Drosophilidae) and the causes of previous incongruences. Mol Phylogenet Evol 2024; 199:108158. [PMID: 39025321 DOI: 10.1016/j.ympev.2024.108158] [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: 04/04/2024] [Revised: 06/28/2024] [Accepted: 07/14/2024] [Indexed: 07/20/2024]
Abstract
Incomplete Lineage Sorting (ILS) and introgression are among the two main factors causing incongruence between gene and species trees. Advances in phylogenomic studies have allowed us to overcome most of these issues, providing reliable phylogenetic hypotheses while revealing the underlying evolutionary scenario. Across the last century, many incongruent phylogenetic reconstructions were recovered for Drosophilidae, employing a limited sampling of genetic markers or species. In these studies, the monophyly and the phylogenetic positioning of the Zygothrica genus group stood out as one of the most controversial questions. Thus, here, we addressed these issues using a phylogenomic approach, while accessing the influence of ILS and introgressions on the diversification of these species and addressing the spatio-temporal scenario associated with their evolution. For this task, the genomes of nine specimens from six Neotropical species belonging to the Zygothrica genus group were sequenced and evaluated in a phylogenetic framework encompassing other 39 species of Drosophilidae. Nucleotide and amino acid sequences recovered for a set of 2,534 single-copy genes by BUSCO were employed to reconstruct maximum likelihood (ML) concatenated and multi-species coalescent (MSC) trees. Likelihood mapping, quartet sampling, and reticulation tests were employed to infer the level and causes of incongruence. Lastly, a penalized-likelihood molecular clock strategy with fossil calibrations was performed to infer divergence times. Taken together, our results recovered the subdivision of Drosophila into six different lineages, one of which clusters species of the Zygothrica genus group (except for H. duncani). The divergence of this lineage was dated to Oligocene ∼ 31 Mya and seems to have occurred in the same timeframe as other key diversification within Drosophila. According to the concatenated and MSC strategies, this lineage is sister to the clade joining Drosophila (Siphlodora) with the Hawaiian Drosophila and Scaptomyza. Likelihood mapping, quartet sampling, reticulation reconstructions as well as introgression tests revealed that this lineage was the target of several hybridization events involving the ancestors of different Drosophila lineages. Thus, our results generally show introgression as a major source of previous incongruence. Nevertheless, the similar diversification times recovered for several of the Neotropical Drosophila lineages also support the scenario of multiple and simultaneous diversifications taking place at the base of Drosophilidae phylogeny, at least in the Neotropics.
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Affiliation(s)
- Maiara Hartwig Bessa
- Programa de Pós-Graduação em Biodiversidade Animal (PPGBA), Universidade Federal de Santa Maria (UFSM), Brazil
| | - Marco Silva Gottschalk
- Programa de Pós-Graduação em Biodiversidade Animal (PPGBDiv), Instituto de Biologia, Universidade Federal de Pelotas (UFPel), Brazil
| | - Lizandra Jaqueline Robe
- Programa de Pós-Graduação em Biodiversidade Animal (PPGBA), Universidade Federal de Santa Maria (UFSM), Brazil.
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16
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Erickson PA, Bangerter A, Gunter A, Polizos NT, Bergland AO. Limited population structure but signals of recent selection in introduced African Fig Fly (Zaprionus indianus) in North America. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.09.20.614190. [PMID: 39386550 PMCID: PMC11463544 DOI: 10.1101/2024.09.20.614190] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 10/12/2024]
Abstract
Invasive species have devastating consequences for human health, food security, and the environment. Many invasive species adapt to new ecological niches following invasion, but little is known about the early steps of adaptation. Here we examine population genomics of a recently introduced drosophilid in North America, the African Fig Fly, Zaprionus indianus. This species is likely intolerant of subfreezing temperatures and recolonizes temperate environments yearly. We generated a new chromosome-level genome assembly for Z. indianus. Using resequencing of over 200 North American individuals collected over four years in temperate Virginia, plus a single collection from subtropical Florida, we tested for signatures of recolonization, population structure, and adaptation within invasive populations. We show founding populations are sometimes small and contain close genetic relatives, yet temporal population structure and differentiation of populations is mostly absent across recurrent recolonization events. Although we find limited signals of genome-wide spatial or temporal population structure, we identify haplotypes on the X chromosome that are repeatedly differentiated between Virginia and Florida populations. These haplotypes show signatures of natural selection and are not found in African populations. We also find evidence for several large structural polymorphisms segregating within North America populations and show X chromosome evolution in invasive populations is strikingly different from the autosomes. These results show that despite limited population structure, populations may rapidly evolve genetic differences early in an invasion. Further uncovering how these genomic regions influence invasive potential and success in new environments will advance our understanding of how organisms evolve in changing environments.
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17
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Lin L, Huang Y, McIntyre J, Chang CH, Colmenares S, Lee YCG. Prevalent Fast Evolution of Genes Involved in Heterochromatin Functions. Mol Biol Evol 2024; 41:msae181. [PMID: 39189646 PMCID: PMC11408610 DOI: 10.1093/molbev/msae181] [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: 03/15/2024] [Revised: 08/14/2024] [Accepted: 08/20/2024] [Indexed: 08/28/2024] Open
Abstract
Heterochromatin is a gene-poor and repeat-rich genomic compartment universally found in eukaryotes. Despite its low transcriptional activity, heterochromatin plays important roles in maintaining genome stability, organizing chromosomes, and suppressing transposable elements. Given the importance of these functions, it is expected that genes involved in heterochromatin regulation would be highly conserved. Yet, a handful of these genes were found to evolve rapidly. To investigate whether these previous findings are anecdotal or general to genes modulating heterochromatin, we compile an exhaustive list of 106 candidate genes involved in heterochromatin functions and investigate their evolution over short and long evolutionary time scales in Drosophila. Our analyses find that these genes exhibit significantly more frequent evolutionary changes, both in the forms of amino acid substitutions and gene copy number change, when compared to genes involved in Polycomb-based repressive chromatin. While positive selection drives amino acid changes within both structured domains with diverse functions and intrinsically disordered regions, purifying selection may have maintained the proportions of intrinsically disordered regions of these proteins. Together with the observed negative associations between the evolutionary rate of these genes and the genomic abundance of transposable elements, we propose an evolutionary model where the fast evolution of genes involved in heterochromatin functions is an inevitable outcome of the unique functional roles of heterochromatin, while the rapid evolution of transposable elements may be an effect rather than cause. Our study provides an important global view of the evolution of genes involved in this critical cellular domain and provides insights into the factors driving the distinctive evolution of heterochromatin.
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Affiliation(s)
- Leila Lin
- Department of Ecology and Evolutionary Biology, University of California, Irvine, CA, USA
| | - Yuheng Huang
- Department of Ecology and Evolutionary Biology, University of California, Irvine, CA, USA
| | - Jennifer McIntyre
- Department of Ecology and Evolutionary Biology, University of California, Irvine, CA, USA
| | - Ching-Ho Chang
- Division of Basic Sciences, Fred Hutchinson Cancer Center, Seattle, WA, USA
| | - Serafin Colmenares
- Department of Cell and Molecular Biology, University of California, Berkeley, CA, USA
| | - Yuh Chwen G Lee
- Department of Ecology and Evolutionary Biology, University of California, Irvine, CA, USA
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18
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Feng S, DeGrey SP, Guédot C, Schoville SD, Pool JE. Genomic Diversity Illuminates the Environmental Adaptation of Drosophila suzukii. Genome Biol Evol 2024; 16:evae195. [PMID: 39235033 PMCID: PMC11421661 DOI: 10.1093/gbe/evae195] [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: 02/12/2024] [Revised: 07/09/2024] [Accepted: 08/21/2024] [Indexed: 09/06/2024] Open
Abstract
Biological invasions carry substantial practical and scientific importance and represent natural evolutionary experiments on contemporary timescales. Here, we investigated genomic diversity and environmental adaptation of the crop pest Drosophila suzukii using whole-genome sequencing data and environmental metadata for 29 population samples from its native and invasive range. Through a multifaceted analysis of this population genomic data, we increase our understanding of the D. suzukii genome, its diversity and its evolution, and we identify an appropriate genotype-environment association pipeline for our dataset. Using this approach, we detect genetic signals of local adaptation associated with nine distinct environmental factors related to altitude, wind speed, precipitation, temperature, and human land use. We uncover unique functional signatures for each environmental variable, such as the prevalence of cuticular genes associated with annual precipitation. We also infer biological commonalities in the adaptation to diverse selective pressures, particularly in terms of the apparent contribution of nervous system evolution to enriched processes (ranging from neuron development to circadian behavior) and to top genes associated with all nine environmental variables. Our findings therefore depict a finer-scale adaptive landscape underlying the rapid invasion success of this agronomically important species.
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Affiliation(s)
- Siyuan Feng
- Laboratory of Genetics, University of Wisconsin–Madison, Madison, WI, USA
| | - Samuel P DeGrey
- Department of Entomology, University of Wisconsin-Madison, Madison, WI, USA
| | - Christelle Guédot
- Department of Entomology, University of Wisconsin-Madison, Madison, WI, USA
| | - Sean D Schoville
- Department of Entomology, University of Wisconsin-Madison, Madison, WI, USA
| | - John E Pool
- Laboratory of Genetics, University of Wisconsin–Madison, Madison, WI, USA
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19
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Pezzi PH, Wheeler LC, Freitas LB, Smith SD. Incomplete lineage sorting and hybridization underlie tree discordance in Petunia and related genera (Petunieae, Solanaceae). Mol Phylogenet Evol 2024; 198:108136. [PMID: 38909873 DOI: 10.1016/j.ympev.2024.108136] [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: 03/27/2024] [Revised: 06/06/2024] [Accepted: 06/17/2024] [Indexed: 06/25/2024]
Abstract
Despite the overarching history of species divergence, phylogenetic studies often reveal distinct topologies across regions of the genome. The sources of these gene tree discordances are variable, but incomplete lineage sorting (ILS) and hybridization are among those with the most biological importance. Petunia serves as a classic system for studying hybridization in the wild. While field studies suggest that hybridization is frequent, the extent of reticulation within Petunia and its closely related genera has never been examined from a phylogenetic perspective. In this study, we used transcriptomic data from 11 Petunia, 16 Calibrachoa, and 10 Fabiana species to illuminate the relationships between these species and investigate whether hybridization played a significant role in the diversification of the clade. We inferred that gene tree discordance within genera is linked to hybridization events along with high levels of ILS due to their rapid diversification. Moreover, network analyses estimated deeper hybridization events between Petunia and Calibrachoa, genera that have different chromosome numbers. Although these genera cannot hybridize at the present time, ancestral hybridization could have played a role in their parallel radiations, as they share the same habitat and life history.
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Affiliation(s)
- Pedro H Pezzi
- Department of Genetics, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.
| | - Lucas C Wheeler
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, USA
| | - Loreta B Freitas
- Department of Genetics, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Stacey D Smith
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, USA
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20
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Guay SY, Patel PH, Thomalla JM, McDermott KL, O'Toole JM, Arnold SE, Obrycki SJ, Wolfner MF, Findlay GD. A newly evolved gene is essential for efficient sperm entry into eggs in Drosophila melanogaster. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.08.08.607187. [PMID: 39149251 PMCID: PMC11326263 DOI: 10.1101/2024.08.08.607187] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 08/17/2024]
Abstract
New genes arise through a variety of evolutionary processes and provide raw material for adaptation in the face of both natural and sexual selection. De novo evolved genes emerge from previously non-protein-coding DNA sequences, and many such genes are expressed in male reproductive structures. In Drosophila melanogaster, several putative de novo genes have evolved essential roles in spermatogenesis, but whether such genes can also impact sperm function beyond the male has not been investigated. We identified a putative de novo gene, katherine johnson (kj), that is required for high levels of male fertility. Males that do not express kj produce and transfer sperm that are stored normally in females, but sperm from these males enter eggs with severely reduced efficiency. Using a tagged transgenic rescue construct, we observed that KJ protein localizes to the nuclear periphery in various stages of spermatogenesis, but is not detectable in mature sperm. These data suggest that kj exerts an effect on sperm development, the loss of which results in reduced fertilization ability. While previous bioinformatic analyses suggested the kj gene was restricted to the melanogaster group of Drosophila, we identified putative orthologs with conserved synteny, male-biased expression, and predicted protein features across the genus, as well as instances of gene loss in some lineages. Thus, kj potentially arose in the Drosophila common ancestor and subsequently evolved an essential role in D. melanogaster. Our results demonstrate a new aspect of male reproduction that has been shaped by new gene evolution and provide a molecular foothold for further investigating the mechanism of sperm entry into eggs in Drosophila.
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Affiliation(s)
- Sara Y Guay
- Department of Biology, College of the Holy Cross, Worcester, MA 01610
| | - Prajal H Patel
- Department of Biology, College of the Holy Cross, Worcester, MA 01610
| | - Jonathon M Thomalla
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853
| | - Kerry L McDermott
- Department of Biology, College of the Holy Cross, Worcester, MA 01610
| | - Jillian M O'Toole
- Department of Biology, College of the Holy Cross, Worcester, MA 01610
| | - Sarah E Arnold
- Department of Biology, College of the Holy Cross, Worcester, MA 01610
| | - Sarah J Obrycki
- Department of Biology, College of the Holy Cross, Worcester, MA 01610
| | - Mariana F Wolfner
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853
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21
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Langdon QK, Groh JS, Aguillon SM, Powell DL, Gunn T, Payne C, Baczenas JJ, Donny A, Dodge TO, Du K, Schartl M, Ríos-Cárdenas O, Gutiérrez-Rodríguez C, Morris M, Schumer M. Swordtail fish hybrids reveal that genome evolution is surprisingly predictable after initial hybridization. PLoS Biol 2024; 22:e3002742. [PMID: 39186811 PMCID: PMC11379403 DOI: 10.1371/journal.pbio.3002742] [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: 12/30/2023] [Revised: 09/06/2024] [Accepted: 07/09/2024] [Indexed: 08/28/2024] Open
Abstract
Over the past 2 decades, biologists have come to appreciate that hybridization, or genetic exchange between distinct lineages, is remarkably common-not just in particular lineages but in taxonomic groups across the tree of life. As a result, the genomes of many modern species harbor regions inherited from related species. This observation has raised fundamental questions about the degree to which the genomic outcomes of hybridization are repeatable and the degree to which natural selection drives such repeatability. However, a lack of appropriate systems to answer these questions has limited empirical progress in this area. Here, we leverage independently formed hybrid populations between the swordtail fish Xiphophorus birchmanni and X. cortezi to address this fundamental question. We find that local ancestry in one hybrid population is remarkably predictive of local ancestry in another, demographically independent hybrid population. Applying newly developed methods, we can attribute much of this repeatability to strong selection in the earliest generations after initial hybridization. We complement these analyses with time-series data that demonstrates that ancestry at regions under selection has remained stable over the past approximately 40 generations of evolution. Finally, we compare our results to the well-studied X. birchmanni × X. malinche hybrid populations and conclude that deeper evolutionary divergence has resulted in stronger selection and higher repeatability in patterns of local ancestry in hybrids between X. birchmanni and X. cortezi.
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Affiliation(s)
- Quinn K. Langdon
- Department of Biology, Stanford University, Stanford, California, United States of America
- Centro de Investigaciones Científicas de las Huastecas “Aguazarca”, A.C., Calnali, Hidalgo, Mexico
| | - Jeffrey S. Groh
- Center for Population Biology and Department of Evolution and Ecology, University of California, Davis, Davis, California, United States of America
| | - Stepfanie M. Aguillon
- Department of Biology, Stanford University, Stanford, California, United States of America
- Centro de Investigaciones Científicas de las Huastecas “Aguazarca”, A.C., Calnali, Hidalgo, Mexico
- Department of Ecology and Evolutionary Biology, University of California, Los Angeles, Los Angeles, United States of America
| | - Daniel L. Powell
- Department of Biology, Stanford University, Stanford, California, United States of America
- Centro de Investigaciones Científicas de las Huastecas “Aguazarca”, A.C., Calnali, Hidalgo, Mexico
- Department of Biological Sciences, Louisiana State University, Baton Rouge, Louisiana, United States of America
| | - Theresa Gunn
- Department of Biology, Stanford University, Stanford, California, United States of America
- Centro de Investigaciones Científicas de las Huastecas “Aguazarca”, A.C., Calnali, Hidalgo, Mexico
| | - Cheyenne Payne
- Department of Biology, Stanford University, Stanford, California, United States of America
- Centro de Investigaciones Científicas de las Huastecas “Aguazarca”, A.C., Calnali, Hidalgo, Mexico
| | - John J. Baczenas
- Department of Biology, Stanford University, Stanford, California, United States of America
| | - Alex Donny
- Department of Biology, Stanford University, Stanford, California, United States of America
- Centro de Investigaciones Científicas de las Huastecas “Aguazarca”, A.C., Calnali, Hidalgo, Mexico
| | - Tristram O. Dodge
- Department of Biology, Stanford University, Stanford, California, United States of America
- Centro de Investigaciones Científicas de las Huastecas “Aguazarca”, A.C., Calnali, Hidalgo, Mexico
| | - Kang Du
- Xiphophorus Genetic Stock Center, Texas State University San Marcos, San Marcos, United States of America
| | - Manfred Schartl
- Xiphophorus Genetic Stock Center, Texas State University San Marcos, San Marcos, United States of America
- Developmental Biochemistry, Biocenter, University of Würzburg, Würzburg, Germany
| | - Oscar Ríos-Cárdenas
- Red de Biología Evolutiva, Instituto de Ecología, A.C., Xalapa, Veracruz, Mexico
| | | | - Molly Morris
- Department of Biological Sciences, Ohio University, Athens, Ohio, United States of America
| | - Molly Schumer
- Department of Biology, Stanford University, Stanford, California, United States of America
- Centro de Investigaciones Científicas de las Huastecas “Aguazarca”, A.C., Calnali, Hidalgo, Mexico
- Freeman Hrabowski Fellow, Howard Hughes Medical Institute, Stanford, California, United States of America
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22
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Yusuf LH, Lemus YS, Thorpe P, Garcia CM, Ritchie MG. Evidence for gene flow and trait reversal during radiation of Mexican Goodeid fish. Heredity (Edinb) 2024; 133:78-87. [PMID: 38858547 PMCID: PMC11286751 DOI: 10.1038/s41437-024-00694-1] [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: 07/06/2023] [Revised: 05/15/2024] [Accepted: 05/16/2024] [Indexed: 06/12/2024] Open
Abstract
Understanding the phylogeographic history of a group and identifying the factors contributing to speciation is an important challenge in evolutionary biology. The Goodeinae are a group of live-bearing fishes endemic to Mexico. Here, we develop genomic resources for species within the Goodeinae and use phylogenomic approaches to characterise their evolutionary history. We sequenced, assembled and annotated the genomes of four Goodeinae species, including Ataeniobius toweri, the only matrotrophic live-bearing fish without a trophotaenia in the group. We estimated timings of species divergence and examined the extent and timing of introgression between the species to assess if this may have occurred during an early radiation, or in more recent episodes of secondary contact. We used branch-site models to detect genome-wide positive selection across Goodeinae, and we specifically asked whether this differs in A. toweri, where loss of placental viviparity has recently occurred. We found evidence of gene flow between geographically isolated species, suggesting vicariant speciation was supplemented by limited post-speciation gene flow, and gene flow may explain previous uncertainties about Goodeid phylogeny. Genes under positive selection in the group are likely to be associated with the switch to live-bearing. Overall, our studies suggest that both volcanism-driven vicariance and changes in reproductive mode influenced radiation in the Goodeinae.
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Affiliation(s)
- Leeban H Yusuf
- Centre for Biological Diversity, School of Biology, University of St Andrews, St Andrews, UK.
| | - Yolitzi Saldívar Lemus
- Centre for Biological Diversity, School of Biology, University of St Andrews, St Andrews, UK
- Department of Biology, Texas State University, San Marcos, TX, USA
| | - Peter Thorpe
- School of Life Sciences, University of Dundee, Dundee, UK
| | - Constantino Macías Garcia
- Instituto de Ecologia, Universidad Nacional Autónoma de México, Ciudad Universitaria, Circuito exterior s/n anexo al Jardín Botánico C. P. 04510, Mexico City CdMx, Mexico
| | - Michael G Ritchie
- Centre for Biological Diversity, School of Biology, University of St Andrews, St Andrews, UK
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23
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Lin L, Huang Y, McIntyre J, Chang CH, Colmenares S, Lee YCG. Prevalent fast evolution of genes involved in heterochromatin functions. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.03.583199. [PMID: 38496614 PMCID: PMC10942301 DOI: 10.1101/2024.03.03.583199] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/19/2024]
Abstract
Heterochromatin is a gene-poor and repeat-rich genomic compartment universally found in eukaryotes. Despite its low transcriptional activity, heterochromatin plays important roles in maintaining genome stability, organizing chromosomes, and suppressing transposable elements (TEs). Given the importance of these functions, it is expected that the genes involved in heterochromatin regulation would be highly conserved. Yet, a handful of these genes were found to evolve rapidly. To investigate whether these previous findings are anecdotal or general to genes modulating heterochromatin, we compile an exhaustive list of 106 candidate genes involved in heterochromatin functions and investigate their evolution over short and long evolutionary time scales in Drosophila. Our analyses find that these genes exhibit significantly more frequent evolutionary changes, both in the forms of amino acid substitutions and gene copy number change, when compared to genes involved in Polycomb-based repressive chromatin. While positive selection drives amino acid changes within both structured domains with diverse functions and intrinsically disordered regions (IDRs), purifying selection may have maintained the proportions of IDRs of these proteins. Together with the observed negative associations between evolutionary rates of these genes and genomic TE abundance, we propose an evolutionary model where the fast evolution of genes involved in heterochromatin functions is an inevitable outcome of the unique functional roles of heterochromatin, while the rapid evolution of TEs may be an effect rather than cause. Our study provides an important global view of the evolution of genes involved in this critical cellular domain and provides insights into the factors driving the distinctive evolution of heterochromatin.
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24
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Whittle CA, Extavour CG. Gene Protein Sequence Evolution Can Predict the Rapid Divergence of Ovariole Numbers in the Drosophila melanogaster Subgroup. Genome Biol Evol 2024; 16:evae118. [PMID: 38848313 PMCID: PMC11272079 DOI: 10.1093/gbe/evae118] [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: 01/19/2024] [Revised: 05/01/2024] [Accepted: 05/30/2024] [Indexed: 06/09/2024] Open
Abstract
Ovaries play key roles in fitness and evolution: they are essential female reproductive structures that develop and house the eggs in sexually reproducing animals. In Drosophila, the mature ovary contains multiple tubular egg-producing structures known as ovarioles. Ovarioles arise from somatic cellular structures in the larval ovary called terminal filaments (TFs), formed by TF cells and subsequently enclosed by sheath (SH) cells. As in many other insects, ovariole number per female varies extensively in Drosophila. At present, however, there is a striking gap of information on genetic mechanisms and evolutionary forces that shape the well-documented rapid interspecies divergence of ovariole numbers. To address this gap, here we studied genes associated with Drosophila melanogaster ovariole number or functions based on recent experimental and transcriptional datasets from larval ovaries, including TFs and SH cells, and assessed their rates and patterns of molecular evolution in five closely related species of the melanogaster subgroup that exhibit species-specific differences in ovariole numbers. From comprehensive analyses of protein sequence evolution (dN/dS), branch-site positive selection, expression specificity (tau), and phylogenetic regressions (phylogenetic generalized least squares), we report evidence of 42 genes that showed signs of playing roles in the genetic basis of interspecies evolutionary change of Drosophila ovariole number. These included the signaling genes upd2 and Ilp5 and extracellular matrix genes vkg and Col4a1, whose dN/dS predicted ovariole numbers among species. Together, we propose a model whereby a set of ovariole-involved gene proteins have an enhanced evolvability, including adaptive evolution, facilitating rapid shifts in ovariole number among Drosophila species.
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Affiliation(s)
- Carrie A Whittle
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138, USA
- Howard Hughes Medical Institute, Chevy Chase, MD, USA
| | - Cassandra G Extavour
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138, USA
- Howard Hughes Medical Institute, Chevy Chase, MD, USA
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138, USA
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25
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Ciezarek AG, Mehta TK, Man A, Ford AGP, Kavembe GD, Kasozi N, Ngatunga BP, Shechonge AH, Tamatamah R, Nyingi DW, Cnaani A, Ndiwa TC, Di Palma F, Turner GF, Genner MJ, Haerty W. Ancient and Recent Hybridization in the Oreochromis Cichlid Fishes. Mol Biol Evol 2024; 41:msae116. [PMID: 38865496 PMCID: PMC11221657 DOI: 10.1093/molbev/msae116] [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: 09/21/2023] [Revised: 05/30/2024] [Accepted: 06/04/2024] [Indexed: 06/14/2024] Open
Abstract
Cichlid fishes of the genus Oreochromis (tilapia) are among the most important fish for inland capture fisheries and global aquaculture. Deliberate introductions of non-native species for fisheries improvement and accidental escapees from farms have resulted in admixture with indigenous species. Such hybridization may be detrimental to native biodiversity, potentially leading to genomic homogenization of populations and the loss of important genetic material associated with local adaptation. By contrast, introgression may fuel diversification when combined with ecological opportunity, by supplying novel genetic combinations. To date, the role of introgression in the evolutionary history of tilapia has not been explored. Here we studied both ancient and recent hybridization in tilapia, using whole genome resequencing of 575 individuals from 23 species. We focused on Tanzania, a natural hotspot of tilapia diversity, and a country where hybridization between exotic and native species in the natural environment has been previously reported. We reconstruct the first genome-scale phylogeny of the genus and reveal prevalent ancient gene flow across the Oreochromis phylogeny. This has likely resulted in the hybrid speciation of one species, O. chungruruensis. We identify multiple cases of recent hybridization between native and introduced species in the wild, linked to the use of non-native species in both capture fisheries improvement and aquaculture. This has potential implications for both conservation of wild populations and the development of the global tilapia aquaculture industry.
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Affiliation(s)
- Adam G Ciezarek
- Earlham Institute, Norwich Research Park, Norwich NR4 7UZ, UK
- Centre of Environment, Fisheries and Aquaculture Science (Cefas), Scientific Advice for Fisheries Management Team (SAFM), Lowestoft NR33 0H5, UK
| | - Tarang K Mehta
- Earlham Institute, Norwich Research Park, Norwich NR4 7UZ, UK
| | - Angela Man
- Earlham Institute, Norwich Research Park, Norwich NR4 7UZ, UK
| | - Antonia G P Ford
- School of Life and Health Sciences, Whitelands College, University of Roehampton, London SW15 4NA, UK
| | | | - Nasser Kasozi
- National Agricultural Research Organisation, Buginyanya Zonal Agricultural Research and Development Institute, Mbale, Uganda
| | | | | | | | | | - Avner Cnaani
- Institute of Animal Science, Agricultural Research Organization, Rishon LeZion 7528809, Israel
| | - Titus C Ndiwa
- Department of Clinical Studies, University of Nairobi, Nairobi, Kenya
| | - Federica Di Palma
- School of Biological Sciences, University of East Anglia, Norwich NR4 7TU, UK
| | - George F Turner
- School of Natural Sciences, Bangor University, Bangor LL57 2UW, UK
| | - Martin J Genner
- School of Biological Sciences, University of Bristol, Bristol BS8 1TQ, UK
| | - Wilfried Haerty
- Earlham Institute, Norwich Research Park, Norwich NR4 7UZ, UK
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26
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Kim BY, Gellert HR, Church SH, Suvorov A, Anderson SS, Barmina O, Beskid SG, Comeault AA, Crown KN, Diamond SE, Dorus S, Fujichika T, Hemker JA, Hrcek J, Kankare M, Katoh T, Magnacca KN, Martin RA, Matsunaga T, Medeiros MJ, Miller DE, Pitnick S, Schiffer M, Simoni S, Steenwinkel TE, Syed ZA, Takahashi A, Wei KHC, Yokoyama T, Eisen MB, Kopp A, Matute D, Obbard DJ, O’Grady PM, Price DK, Toda MJ, Werner T, Petrov DA. Single-fly genome assemblies fill major phylogenomic gaps across the Drosophilidae Tree of Life. PLoS Biol 2024; 22:e3002697. [PMID: 39024225 PMCID: PMC11257246 DOI: 10.1371/journal.pbio.3002697] [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: 11/06/2023] [Accepted: 06/03/2024] [Indexed: 07/20/2024] Open
Abstract
Long-read sequencing is driving rapid progress in genome assembly across all major groups of life, including species of the family Drosophilidae, a longtime model system for genetics, genomics, and evolution. We previously developed a cost-effective hybrid Oxford Nanopore (ONT) long-read and Illumina short-read sequencing approach and used it to assemble 101 drosophilid genomes from laboratory cultures, greatly increasing the number of genome assemblies for this taxonomic group. The next major challenge is to address the laboratory culture bias in taxon sampling by sequencing genomes of species that cannot easily be reared in the lab. Here, we build upon our previous methods to perform amplification-free ONT sequencing of single wild flies obtained either directly from the field or from ethanol-preserved specimens in museum collections, greatly improving the representation of lesser studied drosophilid taxa in whole-genome data. Using Illumina Novaseq X Plus and ONT P2 sequencers with R10.4.1 chemistry, we set a new benchmark for inexpensive hybrid genome assembly at US $150 per genome while assembling genomes from as little as 35 ng of genomic DNA from a single fly. We present 183 new genome assemblies for 179 species as a resource for drosophilid systematics, phylogenetics, and comparative genomics. Of these genomes, 62 are from pooled lab strains and 121 from single adult flies. Despite the sample limitations of working with small insects, most single-fly diploid assemblies are comparable in contiguity (>1 Mb contig N50), completeness (>98% complete dipteran BUSCOs), and accuracy (>QV40 genome-wide with ONT R10.4.1) to assemblies from inbred lines. We present a well-resolved multi-locus phylogeny for 360 drosophilid and 4 outgroup species encompassing all publicly available (as of August 2023) genomes for this group. Finally, we present a Progressive Cactus whole-genome, reference-free alignment built from a subset of 298 suitably high-quality drosophilid genomes. The new assemblies and alignment, along with updated laboratory protocols and computational pipelines, are released as an open resource and as a tool for studying evolution at the scale of an entire insect family.
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Affiliation(s)
- Bernard Y. Kim
- Department of Biology, Stanford University, Stanford, California, United States of America
| | - Hannah R. Gellert
- Department of Biology, Stanford University, Stanford, California, United States of America
| | - Samuel H. Church
- Department of Ecology and Evolutionary Biology, Yale University, New Haven, Connecticut United States of America
| | - Anton Suvorov
- Department of Biological Sciences, Virginia Tech, Blacksburg, Virginia, United States of America
| | - Sean S. Anderson
- Department of Biology, University of North Carolina Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Olga Barmina
- Department of Evolution and Ecology, University of California Davis, Davis, California, United States of America
| | - Sofia G. Beskid
- Department of Biology, Stanford University, Stanford, California, United States of America
| | - Aaron A. Comeault
- School of Environmental and Natural Sciences, Bangor University, Bangor, United Kingdom
| | - K. Nicole Crown
- Department of Biology, Case Western Reserve University, Cleveland, Ohio, United States of America
| | - Sarah E. Diamond
- Department of Biology, Case Western Reserve University, Cleveland, Ohio, United States of America
| | - Steve Dorus
- Center for Reproductive Evolution, Department of Biology, Syracuse University, Syracuse, New York, United States of America
| | - Takako Fujichika
- Department of Biological Sciences, Tokyo Metropolitan University, Tokyo, Japan
| | - James A. Hemker
- Department of Developmental Biology, Stanford University, Stanford, California, United States of America
| | - Jan Hrcek
- Institute of Entomology, Biology Centre, Czech Academy of Sciences, České Budějovice, Czech Republic
| | - Maaria Kankare
- Department of Biological and Environmental Science, University of Jyväskylä, Jyväskylä, Finland
| | - Toru Katoh
- Department of Biological Sciences, Hokkaido University, Sapporo, Japan
| | - Karl N. Magnacca
- Hawaii Invertebrate Program, Division of Forestry & Wildlife, Honolulu, Hawaii, United States of America
| | - Ryan A. Martin
- Department of Biology, Case Western Reserve University, Cleveland, Ohio, United States of America
| | - Teruyuki Matsunaga
- Department of Complexity Science and Engineering, The University of Tokyo, Tokyo, Japan
| | - Matthew J. Medeiros
- Pacific Biosciences Research Center, University of Hawaiʻi, Mānoa, Hawaii, United States of America
| | - Danny E. Miller
- Division of Genetic Medicine, Department of Pediatrics; Department of Laboratory Medicine and Pathology, University of Washington, Seattle, Washington, United States of America
| | - Scott Pitnick
- Center for Reproductive Evolution, Department of Biology, Syracuse University, Syracuse, New York, United States of America
| | - Michele Schiffer
- Daintree Rainforest Observatory, James Cook University, Townsville, Australia
| | - Sara Simoni
- Department of Biology, Stanford University, Stanford, California, United States of America
| | | | - Zeeshan A. Syed
- Center for Reproductive Evolution, Department of Biology, Syracuse University, Syracuse, New York, United States of America
| | - Aya Takahashi
- Department of Biological Sciences, Tokyo Metropolitan University, Tokyo, Japan
| | - Kevin H-C. Wei
- Department of Zoology, The University of British Columbia, Vancouver, Canada
| | - Tsuya Yokoyama
- Department of Biology, Stanford University, Stanford, California, United States of America
| | - Michael B. Eisen
- Department of Cell and Molecular Biology, University of California Berkeley, Berkeley, California, United States of America
- Howard Hughes Medical Institute, University of California Berkeley, Berkeley, California, United States of America
| | - Artyom Kopp
- Department of Evolution and Ecology, University of California Davis, Davis, California, United States of America
| | - Daniel Matute
- Department of Biology, University of North Carolina Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Darren J. Obbard
- Institute of Ecology and Evolution, University of Edinburgh, Edinburgh, United Kingdom
| | - Patrick M. O’Grady
- Department of Entomology, Cornell University, Ithaca, New York, United States of America
| | - Donald K. Price
- School of Life Sciences, University of Nevada Las Vegas, Las Vegas, Nevada, United States of America
| | | | - Thomas Werner
- Department of Biological Sciences, Michigan Technological University, Houghton, Michigan, United States of America
| | - Dmitri A. Petrov
- Department of Biology, Stanford University, Stanford, California, United States of America
- CZ Biohub, Investigator, San Francisco, California, United States of America
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27
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Shropshire JD, Conner WR, Vanderpool D, Hoffmann AA, Turelli M, Cooper BS. Rapid host switching of Wolbachia and even more rapid turnover of their phages and incompatibility-causing loci. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.12.04.569981. [PMID: 38105949 PMCID: PMC10723362 DOI: 10.1101/2023.12.04.569981] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2023]
Abstract
About half of all insect species carry maternally inherited Wolbachia alphaproteobacteria, making Wolbachia the most common endosymbionts known in nature. Often Wolbachia spread to high frequencies within populations due to cytoplasmic incompatibility (CI), a Wolbachia-induced sperm modification caused by prophage-associated genes (cifs) that kill embryos without Wolbachia. Several Wolbachia variants also block viruses, including wMel from Drosophila melanogaster when transinfected into the mosquito Aedes aegypti. CI enables the establishment and stable maintenance of pathogen-blocking wMel in natural Ae. aegypti populations. These transinfections are reducing dengue disease incidence on multiple continents. While it has long been known that closely related Wolbachia occupy distantly related hosts, the timing of Wolbachia host switching and molecular evolution has not been widely quantified. We provide a new, conservative calibration for Wolbachia chronograms based on examples of co-divergence of Wolbachia and their insect hosts. Synthesizing publicly available and new genomic data, we use our calibration to demonstrate that wMel-like variants separated by only about 370,000 years have naturally colonized holometabolous dipteran and hymenopteran insects that diverged approximately 350 million years ago. Data from Wolbachia variants closely related to those currently dominant in D. melanogaster and D. simulans illustrate that cifs are rapidly acquired and lost among Wolbachia genomes, on a time scale of 104-105 years. This turnover occurs with and without the Wovirus prophages that contain them, with closely related cifs found in distantly related phages and distantly related cifs found in closely related phages. We present evidence for purifying selection on CI rescue function and on particular Cif protein domains. Our results quantify the tempo and mode of rapid host switching and horizontal gene transfer that underlie the spread and diversity of Wolbachia sampled from diverse host species. The wMel variants we highlight from hosts in different climates may offer new options for broadening Wolbachia-based biocontrol of diseases and pests.
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Affiliation(s)
- J. Dylan Shropshire
- Division of Biological Sciences, University of Montana, Missoula, Montana, USA
- Department of Biological Sciences, Lehigh University, Bethlehem, Pennsylvania, USA
| | - William R. Conner
- Division of Biological Sciences, University of Montana, Missoula, Montana, USA
| | - Dan Vanderpool
- Forest Service, National Genomics Center for Wildlife and Fish Conservation, Missoula, Montana, USA
| | - Ary A. Hoffmann
- Pest and Environmental Adaptation Research Group, Bio21 Institute and the School of BioSciences, The University of Melbourne, Parkville, Australia
| | - Michael Turelli
- Department of Evolution and Ecology, University of California, Davis, California, USA
| | - Brandon S. Cooper
- Division of Biological Sciences, University of Montana, Missoula, Montana, USA
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28
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Hague MTJ, Wheeler TB, Cooper BS. Comparative analysis of Wolbachia maternal transmission and localization in host ovaries. Commun Biol 2024; 7:727. [PMID: 38877196 PMCID: PMC11178894 DOI: 10.1038/s42003-024-06431-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: 02/17/2024] [Accepted: 06/07/2024] [Indexed: 06/16/2024] Open
Abstract
Many insects and other animals carry microbial endosymbionts that influence their reproduction and fitness. These relationships only persist if endosymbionts are reliably transmitted from one host generation to the next. Wolbachia are maternally transmitted endosymbionts found in most insect species, but transmission rates can vary across environments. Maternal transmission of wMel Wolbachia depends on temperature in natural Drosophila melanogaster hosts and in transinfected Aedes aegypti, where wMel is used to block pathogens that cause human disease. In D. melanogaster, wMel transmission declines in the cold as Wolbachia become less abundant in host ovaries and at the posterior pole plasm (the site of germline formation) in mature oocytes. Here, we assess how temperature affects maternal transmission and underlying patterns of Wolbachia localization across 10 Wolbachia strains diverged up to 50 million years-including strains closely related to wMel-and their natural Drosophila hosts. Many Wolbachia maintain high transmission rates across temperatures, despite highly variable (and sometimes low) levels of Wolbachia in the ovaries and at the developing germline in late-stage oocytes. Identifying strains like closely related wMel-like Wolbachia with stable transmission across variable environmental conditions may improve the efficacy of Wolbachia-based biocontrol efforts as they expand into globally diverse environments.
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Affiliation(s)
| | - Timothy B Wheeler
- Division of Biological Sciences, University of Montana, Missoula, MT, USA
| | - Brandon S Cooper
- Division of Biological Sciences, University of Montana, Missoula, MT, USA
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29
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Hague MT, Wheeler TB, Cooper BS. Comparative analysis of Wolbachia maternal transmission and localization in host ovaries. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.03.583170. [PMID: 38496649 PMCID: PMC10942406 DOI: 10.1101/2024.03.03.583170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/19/2024]
Abstract
Many insects and other animals carry microbial endosymbionts that influence their reproduction and fitness. These relationships only persist if endosymbionts are reliably transmitted from one host generation to the next. Wolbachia are maternally transmitted endosymbionts found in most insect species, but transmission rates can vary across environments. Maternal transmission of wMel Wolbachia depends on temperature in natural Drosophila melanogaster hosts and in transinfected Aedes aegypti, where wMel is used to block pathogens that cause human disease. In D. melanogaster, wMel transmission declines in the cold as Wolbachia become less abundant in host ovaries and at the posterior pole plasm (the site of germline formation) in mature oocytes. Here, we assess how temperature affects maternal transmission and underlying patterns of Wolbachia localization across 10 Wolbachia strains diverged up to 50 million years-including strains closely related to wMel-and their natural Drosophila hosts. Many Wolbachia maintain high transmission rates across temperatures, despite highly variable (and sometimes low) levels of Wolbachia in the ovaries and at the developing germline in late-stage oocytes. Identifying strains like closely related wMel-like Wolbachia with stable transmission across variable environmental conditions may improve the efficacy of Wolbachia-based biocontrol efforts as they expand into globally diverse environments.
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Affiliation(s)
| | - Timothy B. Wheeler
- Division of Biological Sciences, University of Montana, Missoula, Montana, USA
| | - Brandon S. Cooper
- Division of Biological Sciences, University of Montana, Missoula, Montana, USA
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30
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Li XC, Gandara L, Ekelöf M, Richter K, Alexandrov T, Crocker J. Rapid response of fly populations to gene dosage across development and generations. Nat Commun 2024; 15:4551. [PMID: 38811562 PMCID: PMC11137061 DOI: 10.1038/s41467-024-48960-4] [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: 09/06/2023] [Accepted: 05/17/2024] [Indexed: 05/31/2024] Open
Abstract
Although the effects of genetic and environmental perturbations on multicellular organisms are rarely restricted to single phenotypic layers, our current understanding of how developmental programs react to these challenges remains limited. Here, we have examined the phenotypic consequences of disturbing the bicoid regulatory network in early Drosophila embryos. We generated flies with two extra copies of bicoid, which causes a posterior shift of the network's regulatory outputs and a decrease in fitness. We subjected these flies to EMS mutagenesis, followed by experimental evolution. After only 8-15 generations, experimental populations have normalized patterns of gene expression and increased survival. Using a phenomics approach, we find that populations were normalized through rapid increases in embryo size driven by maternal changes in metabolism and ovariole development. We extend our results to additional populations of flies, demonstrating predictability. Together, our results necessitate a broader view of regulatory network evolution at the systems level.
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Affiliation(s)
- Xueying C Li
- European Molecular Biology Laboratory (EMBL), Heidelberg, Germany.
- College of Life Sciences, Beijing Normal University, Beijing, China.
| | - Lautaro Gandara
- European Molecular Biology Laboratory (EMBL), Heidelberg, Germany
| | - Måns Ekelöf
- European Molecular Biology Laboratory (EMBL), Heidelberg, Germany
| | - Kerstin Richter
- European Molecular Biology Laboratory (EMBL), Heidelberg, Germany
| | - Theodore Alexandrov
- European Molecular Biology Laboratory (EMBL), Heidelberg, Germany
- Molecular Medicine Partnership Unit between EMBL and Heidelberg University, Heidelberg, Germany
- BioInnovation Institute, Copenhagen, Denmark
| | - Justin Crocker
- European Molecular Biology Laboratory (EMBL), Heidelberg, Germany.
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31
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Pang XX, Zhang DY. Detection of Ghost Introgression Requires Exploiting Topological and Branch Length Information. Syst Biol 2024; 73:207-222. [PMID: 38224495 PMCID: PMC11129598 DOI: 10.1093/sysbio/syad077] [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: 05/01/2023] [Revised: 12/17/2023] [Accepted: 12/27/2023] [Indexed: 01/17/2024] Open
Abstract
In recent years, the study of hybridization and introgression has made significant progress, with ghost introgression-the transfer of genetic material from extinct or unsampled lineages to extant species-emerging as a key area for research. Accurately identifying ghost introgression, however, presents a challenge. To address this issue, we focused on simple cases involving 3 species with a known phylogenetic tree. Using mathematical analyses and simulations, we evaluated the performance of popular phylogenetic methods, including HyDe and PhyloNet/MPL, and the full-likelihood method, Bayesian Phylogenetics and Phylogeography (BPP), in detecting ghost introgression. Our findings suggest that heuristic approaches relying on site-pattern counts or gene-tree topologies struggle to differentiate ghost introgression from introgression between sampled non-sister species, frequently leading to incorrect identification of donor and recipient species. The full-likelihood method BPP uses multilocus sequence alignments directly-hence taking into account both gene-tree topologies and branch lengths, by contrast, is capable of detecting ghost introgression in phylogenomic datasets. We analyzed a real-world phylogenomic dataset of 14 species of Jaltomata (Solanaceae) to showcase the potential of full-likelihood methods for accurate inference of introgression.
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Affiliation(s)
- Xiao-Xu Pang
- Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, College of Life Sciences, Beijing Normal University, Beijing 100875, China
| | - Da-Yong Zhang
- Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, College of Life Sciences, Beijing Normal University, Beijing 100875, China
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32
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Gao B, Zhu S. The evolutionary novelty of insect defensins: from bacterial killing to toxin neutralization. Cell Mol Life Sci 2024; 81:230. [PMID: 38780625 PMCID: PMC11116330 DOI: 10.1007/s00018-024-05273-5] [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: 02/09/2024] [Revised: 05/05/2024] [Accepted: 05/09/2024] [Indexed: 05/25/2024]
Abstract
Insect host defense comprises two complementary dimensions, microbial killing-mediated resistance and microbial toxin neutralization-mediated resilience, both jointly providing protection against pathogen infections. Insect defensins are a class of effectors of innate immunity primarily responsible for resistance to Gram-positive bacteria. Here, we report a newly originated gene from an ancestral defensin via genetic deletion following gene duplication in Drosophila virilis, which confers an enhanced resilience to Gram-positive bacterial infection. This gene encodes an 18-mer arginine-rich peptide (termed DvirARP) with differences from its parent gene in its pattern of expression, structure and function. DvirARP specifically expresses in D. virilis female adults with a constitutive manner. It adopts a novel fold with a 310 helix and a two CXC motif-containing loop stabilized by two disulfide bridges. DvirARP exhibits no activity on the majority of microorganisms tested and only a weak activity against two Gram-positive bacteria. DvirARP knockout flies are viable and have no obvious defect in reproductivity but they are more susceptible to the DvirARP-resistant Staphylococcus aureus infection than the wild type files, which can be attributable to its ability in neutralization of the S. aureus secreted toxins. Phylogenetic distribution analysis reveals that DvirARP is restrictedly present in the Drosophila subgenus, but independent deletion variations also occur in defensins from the Sophophora subgenus, in support of the evolvability of this class of immune effectors. Our work illustrates for the first time how a duplicate resistance-mediated gene evolves an ability to increase the resilience of a subset of Drosophila species against bacterial infection.
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Affiliation(s)
- Bin Gao
- Group of Peptide Biology and Evolution, State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Shunyi Zhu
- Group of Peptide Biology and Evolution, State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.
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33
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Wallace MA, Obbard DJ. Naturally occurring viruses of Drosophila reduce offspring number and lifespan. Proc Biol Sci 2024; 291:20240518. [PMID: 38747703 DOI: 10.1098/rspb.2024.0518] [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: 03/02/2024] [Accepted: 04/23/2024] [Indexed: 07/31/2024] Open
Abstract
Drosophila remains a pre-eminent insect model system for host-virus interaction, but the host range and fitness consequences of the drosophilid virome are poorly understood. Metagenomic studies have reported approximately 200 viruses associated with Drosophilidae, but few isolates are available to characterize the Drosophila immune response, and most characterization has relied on injection and systemic infection. Here, we use a more natural infection route to characterize the fitness effects of infection and to study a wider range of viruses. We exposed laboratory Drosophila melanogaster to 23 naturally occurring viruses from wild-collected drosophilids. We recorded transmission rates along with two components of female fitness: survival and the lifetime number of adult offspring produced. Nine different viruses transmitted during contact with laboratory D. melanogaster, although for the majority, rates of transmission were less than 20%. Five virus infections led to a significant decrease in lifespan (D. melanogaster Nora virus, D. immigrans Nora virus, Muthill virus, galbut virus and Prestney Burn virus), and three led to a reduction in the total number of offspring. Our findings demonstrate the utility of the Drosophila model for community-level studies of host-virus interactions, and suggest that viral infection could be a substantial fitness burden on wild flies.
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Affiliation(s)
- Megan A Wallace
- Institute of Ecology and Evolution, University of Edinburgh, Ashworth Laboratories, Charlotte Auerbach Road, Edinburgh EH9 3FL, UK
| | - Darren J Obbard
- Institute of Ecology and Evolution, University of Edinburgh, Ashworth Laboratories, Charlotte Auerbach Road, Edinburgh EH9 3FL, UK
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Lee U, Li C, Langer CB, Svetec N, Zhao L. Comparative Single Cell Analysis of Transcriptional Bursting Reveals the Role of Genome Organization on de novo Transcript Origination. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.29.591771. [PMID: 38746255 PMCID: PMC11092510 DOI: 10.1101/2024.04.29.591771] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2024]
Abstract
Spermatogenesis is a key developmental process underlying the origination of newly evolved genes. However, rapid cell type-specific transcriptomic divergence of the Drosophila germline has posed a significant technical barrier for comparative single-cell RNA-sequencing (scRNA-Seq) studies. By quantifying a surprisingly strong correlation between species-and cell type-specific divergence in three closely related Drosophila species, we apply a simple statistical procedure to identify a core set of 198 genes that are highly predictive of cell type identity while remaining robust to species-specific differences that span over 25-30 million years of evolution. We then utilize cell type classifications based on the 198-gene set to show how transcriptional divergence in cell type increases throughout spermatogenic developmental time, contrasting with traditional hourglass models of whole-organism development. With these cross-species cell type classifications, we then investigate the influence of genome organization on the molecular evolution of spermatogenesis vis-a-vis transcriptional bursting. We first demonstrate how mechanistic control of pre-meiotic transcription is achieved by altering transcriptional burst size while post-meiotic control is exerted via altered bursting frequency. We then report how global differences in autosomal vs. X chromosomal transcription likely arise in a developmental stage preceding full testis organogenesis by showing evolutionarily conserved decreases in X-linked transcription bursting kinetics in all examined somatic and germline cell types. Finally, we provide evidence supporting the cultivator model of de novo gene origination by demonstrating how the appearance of newly evolved testis-specific transcripts potentially provides short-range regulation of the transcriptional bursting properties of neighboring genes during key stages of spermatogenesis.
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35
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Plessy C, Mansfield MJ, Bliznina A, Masunaga A, West C, Tan Y, Liu AW, Grašič J, Del Río Pisula MS, Sánchez-Serna G, Fabrega-Torrus M, Ferrández-Roldán A, Roncalli V, Navratilova P, Thompson EM, Onuma T, Nishida H, Cañestro C, Luscombe NM. Extreme genome scrambling in marine planktonic Oikopleura dioica cryptic species. Genome Res 2024; 34:426-440. [PMID: 38621828 PMCID: PMC11067885 DOI: 10.1101/gr.278295.123] [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: 07/19/2023] [Accepted: 02/28/2024] [Indexed: 04/17/2024]
Abstract
Genome structural variations within species are rare. How selective constraints preserve gene order and chromosome structure is a central question in evolutionary biology that remains unsolved. Our sequencing of several genomes of the appendicularian tunicate Oikopleura dioica around the globe reveals extreme genome scrambling caused by thousands of chromosomal rearrangements, although showing no obvious morphological differences between these animals. The breakpoint accumulation rate is an order of magnitude higher than in ascidian tunicates, nematodes, Drosophila, or mammals. Chromosome arms and sex-specific regions appear to be the primary unit of macrosynteny conservation. At the microsyntenic level, scrambling did not preserve operon structures, suggesting an absence of selective pressure to maintain them. The uncoupling of the genome scrambling with morphological conservation in O. dioica suggests the presence of previously unnoticed cryptic species and provides a new biological system that challenges our previous vision of speciation in which similar animals always share similar genome structures.
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Affiliation(s)
- Charles Plessy
- Genomics and Regulatory Systems Unit, Okinawa Institute of Science and Technology Graduate University (OIST), Onna-son, Okinawa 904-0495, Japan;
| | - Michael J Mansfield
- Genomics and Regulatory Systems Unit, Okinawa Institute of Science and Technology Graduate University (OIST), Onna-son, Okinawa 904-0495, Japan
| | - Aleksandra Bliznina
- Genomics and Regulatory Systems Unit, Okinawa Institute of Science and Technology Graduate University (OIST), Onna-son, Okinawa 904-0495, Japan
| | - Aki Masunaga
- Genomics and Regulatory Systems Unit, Okinawa Institute of Science and Technology Graduate University (OIST), Onna-son, Okinawa 904-0495, Japan
| | - Charlotte West
- Genomics and Regulatory Systems Unit, Okinawa Institute of Science and Technology Graduate University (OIST), Onna-son, Okinawa 904-0495, Japan
| | - Yongkai Tan
- Genomics and Regulatory Systems Unit, Okinawa Institute of Science and Technology Graduate University (OIST), Onna-son, Okinawa 904-0495, Japan
| | - Andrew W Liu
- Genomics and Regulatory Systems Unit, Okinawa Institute of Science and Technology Graduate University (OIST), Onna-son, Okinawa 904-0495, Japan
| | - Jan Grašič
- Genomics and Regulatory Systems Unit, Okinawa Institute of Science and Technology Graduate University (OIST), Onna-son, Okinawa 904-0495, Japan
| | - María Sara Del Río Pisula
- Genomics and Regulatory Systems Unit, Okinawa Institute of Science and Technology Graduate University (OIST), Onna-son, Okinawa 904-0495, Japan
| | - Gaspar Sánchez-Serna
- Departament de Genètica, Microbiologia i Estadística, Facultat de Biologia, Universitat de Barcelona (UB), Barcelona 08028, Spain
- Institut de Recerca de la Biodiversitat (IRBio), Universitat de Barcelona (UB), Barcelona 08028, Spain
| | - Marc Fabrega-Torrus
- Departament de Genètica, Microbiologia i Estadística, Facultat de Biologia, Universitat de Barcelona (UB), Barcelona 08028, Spain
- Institut de Recerca de la Biodiversitat (IRBio), Universitat de Barcelona (UB), Barcelona 08028, Spain
| | - Alfonso Ferrández-Roldán
- Departament de Genètica, Microbiologia i Estadística, Facultat de Biologia, Universitat de Barcelona (UB), Barcelona 08028, Spain
- Institut de Recerca de la Biodiversitat (IRBio), Universitat de Barcelona (UB), Barcelona 08028, Spain
| | - Vittoria Roncalli
- Departament de Genètica, Microbiologia i Estadística, Facultat de Biologia, Universitat de Barcelona (UB), Barcelona 08028, Spain
- Institut de Recerca de la Biodiversitat (IRBio), Universitat de Barcelona (UB), Barcelona 08028, Spain
| | - Pavla Navratilova
- Centre of Plant Structural and Functional Genomics, Institute of Experimental Botany, 779 00 Olomouc, Czech Republic
- Sars International Centre, University of Bergen, Bergen N-5008, Norway
| | - Eric M Thompson
- Sars International Centre, University of Bergen, Bergen N-5008, Norway
- Department of Biological Sciences, University of Bergen, Bergen N-5020, Norway
| | - Takeshi Onuma
- Faculty of Science, Kagoshima University, Kagoshima 890-0065, Japan
- Department of Biological Sciences, Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan
| | - Hiroki Nishida
- Department of Biological Sciences, Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan
| | - Cristian Cañestro
- Departament de Genètica, Microbiologia i Estadística, Facultat de Biologia, Universitat de Barcelona (UB), Barcelona 08028, Spain
- Institut de Recerca de la Biodiversitat (IRBio), Universitat de Barcelona (UB), Barcelona 08028, Spain
| | - Nicholas M Luscombe
- Genomics and Regulatory Systems Unit, Okinawa Institute of Science and Technology Graduate University (OIST), Onna-son, Okinawa 904-0495, Japan
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Aguillon SM, Haase Cox SK, Langdon QK, Gunn TR, Baczenas JJ, Banerjee SM, Donny AE, Moran BM, Gutiérrez-Rodríguez C, Ríos-Cárdenas O, Morris MR, Powell DL, Schumer M. Pervasive gene flow despite strong and varied reproductive barriers in swordtails. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.16.589374. [PMID: 38659793 PMCID: PMC11042374 DOI: 10.1101/2024.04.16.589374] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/26/2024]
Abstract
One of the mechanisms that can lead to the formation of new species occurs through the evolution of reproductive barriers. However, recent research has demonstrated that hybridization has been pervasive across the tree of life even in the presence of strong barriers. Swordtail fishes (genus Xiphophorus) are an emerging model system for studying the interface between these barriers and hybridization. We document overlapping mechanisms that act as barriers between closely related species, X. birchmanni and X. cortezi, by combining genomic sequencing from natural hybrid populations, artificial crosses, behavioral assays, sperm performance, and developmental studies. We show that strong assortative mating plays a key role in maintaining subpopulations with distinct ancestry in natural hybrid populations. Lab experiments demonstrate that artificial F1 crosses experience dysfunction: crosses with X. birchmanni females were largely inviable and crosses with X. cortezi females had a heavily skewed sex ratio. Using F2 hybrids we identify several genomic regions that strongly impact hybrid viability. Strikingly, two of these regions underlie genetic incompatibilities in hybrids between X. birchmanni and its sister species X. malinche. Our results demonstrate that ancient hybridization has played a role in the origin of this shared genetic incompatibility. Moreover, ancestry mismatch at these incompatible regions has remarkably similar consequences for phenotypes and hybrid survival in X. cortezi × X. birchmanni hybrids as in X. malinche × X. birchmanni hybrids. Our findings identify varied reproductive barriers that shape genetic exchange between naturally hybridizing species and highlight the complex evolutionary outcomes of hybridization.
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Affiliation(s)
- Stepfanie M. Aguillon
- Department of Biology, Stanford University, Stanford, CA, USA
- Centro de Investigaciones Científicas de las Huastecas “Aguazarca”, A.C., Calnali, Hidalgo, México
- Department of Ecology and Evolutionary Biology, University of California, Los Angeles, Los Angeles, CA, USA
| | | | - Quinn K. Langdon
- Department of Biology, Stanford University, Stanford, CA, USA
- Centro de Investigaciones Científicas de las Huastecas “Aguazarca”, A.C., Calnali, Hidalgo, México
- Gladstone Institute of Virology, Gladstone Institutes, San Francisco, CA, USA
| | - Theresa R. Gunn
- Department of Biology, Stanford University, Stanford, CA, USA
- Centro de Investigaciones Científicas de las Huastecas “Aguazarca”, A.C., Calnali, Hidalgo, México
| | | | - Shreya M. Banerjee
- Department of Biology, Stanford University, Stanford, CA, USA
- Center for Population Biology, University of California, Davis, Davis, CA, USA
| | | | - Benjamin M. Moran
- Department of Biology, Stanford University, Stanford, CA, USA
- Centro de Investigaciones Científicas de las Huastecas “Aguazarca”, A.C., Calnali, Hidalgo, México
| | | | - Oscar Ríos-Cárdenas
- Red de Biología Evolutiva, Instituto de Ecología A.C., Xalapa, Veracruz, México
| | - Molly R. Morris
- Department of Biological Sciences, Ohio University, Athens, Ohio, USA
| | - Daniel L. Powell
- Department of Biology, Stanford University, Stanford, CA, USA
- Centro de Investigaciones Científicas de las Huastecas “Aguazarca”, A.C., Calnali, Hidalgo, México
| | - Molly Schumer
- Department of Biology, Stanford University, Stanford, CA, USA
- Centro de Investigaciones Científicas de las Huastecas “Aguazarca”, A.C., Calnali, Hidalgo, México
- Freeman Hrabowski Fellow, Howard Hughes Medical Institute, Chevy Chase, Maryland, USA
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37
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Rosser N, Seixas F, Queste LM, Cama B, Mori-Pezo R, Kryvokhyzha D, Nelson M, Waite-Hudson R, Goringe M, Costa M, Elias M, Mendes Eleres de Figueiredo C, Freitas AVL, Joron M, Kozak K, Lamas G, Martins ARP, McMillan WO, Ready J, Rueda-Muñoz N, Salazar C, Salazar P, Schulz S, Shirai LT, Silva-Brandão KL, Mallet J, Dasmahapatra KK. Hybrid speciation driven by multilocus introgression of ecological traits. Nature 2024; 628:811-817. [PMID: 38632397 PMCID: PMC11041799 DOI: 10.1038/s41586-024-07263-w] [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: 09/26/2023] [Accepted: 03/01/2024] [Indexed: 04/19/2024]
Abstract
Hybridization allows adaptations to be shared among lineages and may trigger the evolution of new species1,2. However, convincing examples of homoploid hybrid speciation remain rare because it is challenging to demonstrate that hybridization was crucial in generating reproductive isolation3. Here we combine population genomic analysis with quantitative trait locus mapping of species-specific traits to examine a case of hybrid speciation in Heliconius butterflies. We show that Heliconius elevatus is a hybrid species that is sympatric with both parents and has persisted as an independently evolving lineage for at least 180,000 years. This is despite pervasive and ongoing gene flow with one parent, Heliconius pardalinus, which homogenizes 99% of their genomes. The remaining 1% introgressed from the other parent, Heliconius melpomene, and is scattered widely across the H. elevatus genome in islands of divergence from H. pardalinus. These islands contain multiple traits that are under disruptive selection, including colour pattern, wing shape, host plant preference, sex pheromones and mate choice. Collectively, these traits place H. elevatus on its own adaptive peak and permit coexistence with both parents. Our results show that speciation was driven by introgression of ecological traits, and that speciation with gene flow is possible with a multilocus genetic architecture.
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Affiliation(s)
- Neil Rosser
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, USA.
- Department of Biology, University of York, York, UK.
| | - Fernando Seixas
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, USA
| | | | - Bruna Cama
- Department of Biology, University of York, York, UK
| | - Ronald Mori-Pezo
- URKU Estudios Amazónicos, Tarapoto, Perú
- Universidad Nacional Autónoma de Alto Amazona, Yurimaguas, Perú
| | - Dmytro Kryvokhyzha
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, USA
- Department of Clinical Sciences, Lund University Diabetes Centre, Malmö, Sweden
| | | | | | - Matt Goringe
- Department of Biology, University of York, York, UK
| | | | - Marianne Elias
- Institut Systématique, Evolution, Biodiversité, UMR 7205 MNHN-CNRS-EPHE-UPMC Sorbonne Universités, Muséum National d'Histoire Naturelle, Paris, France
- Smithsonian Tropical Research Institute, Panama City, Panama
| | - Clarisse Mendes Eleres de Figueiredo
- Institute for Biological Sciences, Federal University of Pará (UFPA), Belém, Brazil
- Centre for Advanced Studies of Biodiversity (CEABIO), Belém, Brazil
| | - André Victor Lucci Freitas
- Departamento de Biologia Animal and Museu de Diversidade Biológica, Instituto de Biologia, Universidade Estadual de Campinas, São Paulo, Brazil
| | - Mathieu Joron
- Centre d'Ecologie Fonctionnelle et Evolutive, UMR 5175 CNRS, Université de Montpellier-Université Paul Valéry Montpellier-EPHE, Montpellier, France
| | - Krzysztof Kozak
- Smithsonian Tropical Research Institute, Panama City, Panama
| | - Gerardo Lamas
- Museo de Historia Natural, Universidad Nacional Mayor de San Marcos, Lima, Peru
| | | | - W Owen McMillan
- Smithsonian Tropical Research Institute, Panama City, Panama
| | - Jonathan Ready
- Institute for Biological Sciences, Federal University of Pará (UFPA), Belém, Brazil
- Centre for Advanced Studies of Biodiversity (CEABIO), Belém, Brazil
| | - Nicol Rueda-Muñoz
- Biology Program, Faculty of Natural Sciences, Universidad del Rosario, Bogotá, Colombia
| | - Camilo Salazar
- Biology Program, Faculty of Natural Sciences, Universidad del Rosario, Bogotá, Colombia
| | - Patricio Salazar
- Ecology and Evolutionary Biology, School of Biosciences, University of Sheffield, Sheffield, UK
| | - Stefan Schulz
- Institut für Organische Chemie, Technische Universität Braunschweig, Braunschweig, Germany
| | - Leila T Shirai
- Departamento de Biologia Animal and Museu de Diversidade Biológica, Instituto de Biologia, Universidade Estadual de Campinas, São Paulo, Brazil
| | - Karina L Silva-Brandão
- Leibniz Institute for the Analysis of Biodiversity Change, Museum de Natur Hamburg Zoology, Hamburg, Germany
| | - James Mallet
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, USA.
| | - Kanchon K Dasmahapatra
- Department of Biology, University of York, York, UK
- Leverhulme Centre for Anthropocene Biodiversity, Department of Biology, University of York, York, UK
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Dietz L, Mayer C, Stolle E, Eberle J, Misof B, Podsiadlowski L, Niehuis O, Ahrens D. Metazoa-level USCOs as markers in species delimitation and classification. Mol Ecol Resour 2024; 24:e13921. [PMID: 38146909 DOI: 10.1111/1755-0998.13921] [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: 10/15/2023] [Revised: 12/06/2023] [Accepted: 12/13/2023] [Indexed: 12/27/2023]
Abstract
Metazoa-level universal single-copy orthologs (mzl-USCOs) are universally applicable markers for DNA taxonomy in animals that can replace or supplement single-gene barcodes. Previously, mzl-USCOs from target enrichment data were shown to reliably distinguish species. Here, we tested whether USCOs are an evenly distributed, representative sample of a given metazoan genome and therefore able to cope with past hybridization events and incomplete lineage sorting. This is relevant for coalescent-based species delimitation approaches, which critically depend on the assumption that the investigated loci do not exhibit autocorrelation due to physical linkage. Based on 239 chromosome-level assembled genomes, we confirmed that mzl-USCOs are genetically unlinked for practical purposes and a representative sample of a genome in terms of reciprocal distances between USCOs on a chromosome and of distribution across chromosomes. We tested the suitability of mzl-USCOs extracted from genomes for species delimitation and phylogeny in four case studies: Anopheles mosquitos, Drosophila fruit flies, Heliconius butterflies and Darwin's finches. In almost all instances, USCOs allowed delineating species and yielded phylogenies that corresponded to those generated from whole genome data. Our phylogenetic analyses demonstrate that USCOs may complement single-gene DNA barcodes and provide more accurate taxonomic inferences. Combining USCOs from sources that used different versions of ortholog reference libraries to infer marker orthology may be challenging and, at times, impact taxonomic conclusions. However, we expect this problem to become less severe as the rapidly growing number of reference genomes provides a better representation of the number and diversity of organismal lineages.
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Affiliation(s)
- Lars Dietz
- Museum A. Koenig, Leibniz Institute for the Analysis of Biodiversity Change, Bonn, Germany
| | - Christoph Mayer
- Museum A. Koenig, Leibniz Institute for the Analysis of Biodiversity Change, Bonn, Germany
| | - Eckart Stolle
- Museum A. Koenig, Leibniz Institute for the Analysis of Biodiversity Change, Bonn, Germany
| | - Jonas Eberle
- Museum A. Koenig, Leibniz Institute for the Analysis of Biodiversity Change, Bonn, Germany
- Paris-Lodron-University, Salzburg, Austria
| | - Bernhard Misof
- Museum A. Koenig, Leibniz Institute for the Analysis of Biodiversity Change, Bonn, Germany
- Rheinische Friedrich-Wilhelms-Universität Bonn, Bonn, Germany
| | - Lars Podsiadlowski
- Museum A. Koenig, Leibniz Institute for the Analysis of Biodiversity Change, Bonn, Germany
| | - Oliver Niehuis
- Abt. Evolutionsbiologie und Ökologie, Institut für Biologie I, Albert-Ludwigs-Universität Freiburg, Freiburg, Germany
| | - Dirk Ahrens
- Museum A. Koenig, Leibniz Institute for the Analysis of Biodiversity Change, Bonn, Germany
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Antoniolli HR, Pita S, Deprá M, Valente VL. Horizontal transfer and the widespread presence of Galileo transposons in Drosophilidae (Insecta: Diptera). Genet Mol Biol 2024; 46:e20230143. [PMID: 38569056 PMCID: PMC10990002 DOI: 10.1590/1678-4685-gmb-2023-0143] [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: 05/08/2023] [Accepted: 01/30/2024] [Indexed: 04/05/2024] Open
Abstract
Galileo is a transposon notoriously involved with inversions in Drosophila buzzatii by ectopic recombination. Although widespread in Drosophila, little is known about this transposon in other lineages of Drosophilidae. Here, the abundance of the canonical Galileo and its evolutionary history in Drosophilidae genomes was estimated and reconstructed across genera within its two subfamilies. Sequences of this transposon were masked in these genomes and their transposase sequences were recovered using BLASTn. Phylogenetic analyses were employed to reconstruct their evolutionary history and compare it to that of host genomes. Galileo was found in nearly all 163 species, however, only 37 harbored nearly complete transposase sequences. In the remaining, Galileo was found highly fragmented. Copies from related species were clustered, however horizontal transfer events were detected between the melanogaster and montium groups of Drosophila, and between the latter and the Lordiphosa genus. The similarity of sequences found in the virilis and willistoni groups of Drosophila was found to be a consequence of lineage sorting. Therefore, the evolution of Galileo is primarily marked by vertical transmission and long-term inactivation, mainly through the deletion of open reading frames. The latter has the potential to lead copies of this transposon to become miniature inverted-repeat transposable elements.
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Affiliation(s)
- Henrique R.M. Antoniolli
- Universidade Federal do Rio Grande do Sul (UFRGS), Laboratório de
Drosophila, Programa de Pós-Graduação em Genética e Biologia Molecular, Porto
Alegre, RS, Brazil
| | - Sebastián Pita
- Universidad de la República (UdelaR), Facultad de Ciencias, Sección
Genética Evolutiva, Montevideo, Uruguay
| | - Maríndia Deprá
- Universidade Federal do Rio Grande do Sul (UFRGS), Laboratório de
Drosophila, Programa de Pós-Graduação em Genética e Biologia Molecular, Porto
Alegre, RS, Brazil
| | - Vera L.S. Valente
- Universidade Federal do Rio Grande do Sul (UFRGS), Laboratório de
Drosophila, Programa de Pós-Graduação em Genética e Biologia Molecular, Porto
Alegre, RS, Brazil
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40
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Gardner C, Chen J, Hadfield C, Lu Z, Debruin D, Zhan Y, Donlin MJ, Lin Z, Ahn TH. Chromosome-level Subgenome-aware de novo Assembly of Saccharomyces bayanus Provides Insight into Genome Divergence after Hybridization. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.17.585453. [PMID: 38562692 PMCID: PMC10983925 DOI: 10.1101/2024.03.17.585453] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
Interspecies hybridization is prevalent in various eukaryotic lineages and plays important roles in phenotypic diversification, adaption, and speciation. To better understand the changes that occurred in the different subgenomes of a hybrid species and how they facilitated adaptation, we completed chromosome-level de novo assemblies of all 16 pairs chromosomes for a recently formed hybrid yeast, Saccharomyces bayanus strain CBS380 (IFO11022), using Nanopore MinION long-read sequencing. Characterization of S. bayanus subgenomes and comparative analysis with the genomes of its parent species, S. uvarum and S. eubayanus, provide several new insights into understanding genome evolution after a relatively recent hybridization. For instance, multiple recombination events between the two subgenomes have been observed in each chromosome, followed by loss of heterozygosity (LOH) in most chromosomes in nine chromosome pairs. In addition to maintaining nearly all gene content and synteny from its parental genomes, S. bayanus has acquired many genes from other yeast species, primarily through the introgression of S. cerevisiae, such as those involved in the maltose metabolism. In addition, the patterns of recombination and LOH suggest an allotetraploid origin of S. bayanus. The gene acquisition and rapid LOH in the hybrid genome probably facilitated its adaption to maltose brewing environments and mitigated the maladaptive effect of hybridization.
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Affiliation(s)
- Cory Gardner
- Department of Computer Science, Saint Louis University, St. Louis, MO, USA
- Program in Bioinformatics and Computational Biology, Saint Louis University, St. Louis, MO, USA
| | - Junhao Chen
- Department of Biology, Saint Louis University, St. Louis, MO, USA
| | - Christina Hadfield
- Program in Bioinformatics and Computational Biology, Saint Louis University, St. Louis, MO, USA
| | - Zhaolian Lu
- Department of Biology, Saint Louis University, St. Louis, MO, USA
| | - David Debruin
- Program in Bioinformatics and Computational Biology, Saint Louis University, St. Louis, MO, USA
| | - Yu Zhan
- Department of Biology, Saint Louis University, St. Louis, MO, USA
| | - Maureen J. Donlin
- Program in Bioinformatics and Computational Biology, Saint Louis University, St. Louis, MO, USA
- Department of Biochemistry and Molecular Biology, Saint Louis University, St. Louis, MO, USA
| | - Zhenguo Lin
- Program in Bioinformatics and Computational Biology, Saint Louis University, St. Louis, MO, USA
- Department of Biology, Saint Louis University, St. Louis, MO, USA
| | - Tae-Hyuk Ahn
- Department of Computer Science, Saint Louis University, St. Louis, MO, USA
- Program in Bioinformatics and Computational Biology, Saint Louis University, St. Louis, MO, USA
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Bastide H, Legout H, Dogbo N, Ogereau D, Prediger C, Carcaud J, Filée J, Garnery L, Gilbert C, Marion-Poll F, Requier F, Sandoz JC, Yassin A. The genome of the blind bee louse fly reveals deep convergences with its social host and illuminates Drosophila origins. Curr Biol 2024; 34:1122-1132.e5. [PMID: 38309271 DOI: 10.1016/j.cub.2024.01.034] [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: 01/22/2023] [Revised: 10/22/2023] [Accepted: 01/12/2024] [Indexed: 02/05/2024]
Abstract
Social insects' nests harbor intruders known as inquilines,1 which are usually related to their hosts.2,3 However, distant non-social inquilines may also show convergences with their hosts,4,5 although the underlying genomic changes remain unclear. We analyzed the genome of the wingless and blind bee louse fly Braula coeca, an inquiline kleptoparasite of the western honey bee, Apis mellifera.6,7 Using large phylogenomic data, we confirmed recent accounts that the bee louse fly is a drosophilid8,9 and showed that it had likely evolved from a sap-breeder ancestor associated with honeydew and scale insects' wax. Unlike many parasites, the bee louse fly genome did not show significant erosion or strict reliance on an endosymbiont, likely due to a relatively recent age of inquilinism. However, we observed a horizontal transfer of a transposon and a striking parallel evolution in a set of gene families between the honey bee and the bee louse fly. Convergences included genes potentially involved in metabolism and immunity and the loss of nearly all bitter-tasting gustatory receptors, in agreement with life in a protective nest and a diet of honey, pollen, and beeswax. Vision and odorant receptor genes also exhibited rapid losses. Only genes whose orthologs in the closely related Drosophila melanogaster respond to honey bee pheromone components or floral aroma were retained, whereas the losses included orthologous receptors responsive to the anti-ovarian honey bee queen pheromones. Hence, deep genomic convergences can underlie major phenotypic transitions during the evolution of inquilinism between non-social parasites and their social hosts.
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Affiliation(s)
- Héloïse Bastide
- Université Paris-Saclay, CNRS, IRD, UMR Évolution, Génomes, Comportement et Écologie, 91198 Gif-sur-Yvette, France.
| | - Hélène Legout
- Université Paris-Saclay, CNRS, IRD, UMR Évolution, Génomes, Comportement et Écologie, 91198 Gif-sur-Yvette, France
| | - Noé Dogbo
- Université Paris-Saclay, CNRS, IRD, UMR Évolution, Génomes, Comportement et Écologie, 91198 Gif-sur-Yvette, France
| | - David Ogereau
- Université Paris-Saclay, CNRS, IRD, UMR Évolution, Génomes, Comportement et Écologie, 91198 Gif-sur-Yvette, France
| | - Carolina Prediger
- Université Paris-Saclay, CNRS, IRD, UMR Évolution, Génomes, Comportement et Écologie, 91198 Gif-sur-Yvette, France
| | - Julie Carcaud
- Université Paris-Saclay, CNRS, IRD, UMR Évolution, Génomes, Comportement et Écologie, 91198 Gif-sur-Yvette, France
| | - Jonathan Filée
- Université Paris-Saclay, CNRS, IRD, UMR Évolution, Génomes, Comportement et Écologie, 91198 Gif-sur-Yvette, France
| | - Lionel Garnery
- Université Paris-Saclay, CNRS, IRD, UMR Évolution, Génomes, Comportement et Écologie, 91198 Gif-sur-Yvette, France
| | - Clément Gilbert
- Université Paris-Saclay, CNRS, IRD, UMR Évolution, Génomes, Comportement et Écologie, 91198 Gif-sur-Yvette, France
| | - Frédéric Marion-Poll
- Université Paris-Saclay, CNRS, IRD, UMR Évolution, Génomes, Comportement et Écologie, 91198 Gif-sur-Yvette, France; Université Paris-Saclay, AgroParisTech, 91123 Palaiseau Cedex, France
| | - Fabrice Requier
- Université Paris-Saclay, CNRS, IRD, UMR Évolution, Génomes, Comportement et Écologie, 91198 Gif-sur-Yvette, France
| | - Jean-Christophe Sandoz
- Université Paris-Saclay, CNRS, IRD, UMR Évolution, Génomes, Comportement et Écologie, 91198 Gif-sur-Yvette, France
| | - Amir Yassin
- Université Paris-Saclay, CNRS, IRD, UMR Évolution, Génomes, Comportement et Écologie, 91198 Gif-sur-Yvette, France
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Bladen J, Cooper JC, Ridges JT, Guo P, Phadnis N. A new hybrid incompatibility locus between Drosophila melanogaster and Drosophila sechellia. Genetics 2024; 226:iyae001. [PMID: 38184848 PMCID: PMC10917521 DOI: 10.1093/genetics/iyae001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2023] [Revised: 11/11/2023] [Accepted: 12/15/2023] [Indexed: 01/09/2024] Open
Abstract
Despite the fundamental importance of hybrid incompatibilities to the process of speciation, there are few cases where the evolution and genetic architecture of hybrid incompatibilities are understood. One of the longest studied hybrid incompatibilities causes F1 hybrid male inviability in crosses between Drosophila melanogaster females and males from the Drosophila simulans clade of species-Drosophila simulans, Drosophila mauritiana, and Drosophila sechellia. Here, we discover dramatic differences in the manifestation of this lethal hybrid incompatibility among the D. simulans clade of species. In particular, F1 hybrid males between D. melanogaster and D. sechellia are resistant to hybrid rescue through RNAi knockdown of an essential hybrid incompatibility gene. To understand the genetic basis of this inter-species difference in hybrid rescue, we developed a triple-hybrid mapping method. Our results show that 2 discrete large effect loci and many dispersed small effect changes across the genome underlie D. sechellia aversion to hybrid rescue. The large effect loci encompass a known incompatibility gene Lethal hybrid rescue (Lhr) and previously unknown factor, Sechellia aversion to hybrid rescue (Satyr). These results show that the genetic architecture of F1 hybrid male inviability is overlapping but not identical in the 3 inter-species crosses. Our results raise questions about whether new hybrid incompatibility genes can integrate into an existing hybrid incompatibility thus increasing in complexity over time, or if the continued evolution of genes can gradually strengthen an existing hybrid incompatibility.
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Affiliation(s)
- Jackson Bladen
- School of Biological Sciences, University of Utah, Salt Lake City, UT 84112, USA
| | - Jacob C Cooper
- School of Biological Sciences, University of Utah, Salt Lake City, UT 84112, USA
| | - Jackson T Ridges
- School of Biological Sciences, University of Utah, Salt Lake City, UT 84112, USA
| | - Ping Guo
- School of Biological Sciences, University of Utah, Salt Lake City, UT 84112, USA
| | - Nitin Phadnis
- School of Biological Sciences, University of Utah, Salt Lake City, UT 84112, USA
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Nunes WVB, Oliveira DS, Dias GDR, Carvalho AB, Caruso ÍP, Biselli JM, Guegen N, Akkouche A, Burlet N, Vieira C, Carareto CMA. A comprehensive evolutionary scenario for the origin and neofunctionalization of the Drosophila speciation gene Odysseus (OdsH). G3 (BETHESDA, MD.) 2024; 14:jkad299. [PMID: 38156703 PMCID: PMC10917504 DOI: 10.1093/g3journal/jkad299] [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: 11/22/2023] [Revised: 11/22/2023] [Accepted: 12/20/2023] [Indexed: 01/03/2024]
Abstract
Odysseus (OdsH) was the first speciation gene described in Drosophila related to hybrid sterility in offspring of mating between Drosophila mauritiana and Drosophila simulans. Its origin is attributed to the duplication of the gene unc-4 in the subgenus Sophophora. By using a much larger sample of Drosophilidae species, we showed that contrary to what has been previously proposed, OdsH origin occurred 62 MYA. Evolutionary rates, expression, and transcription factor-binding sites of OdsH evidence that it may have rapidly experienced neofunctionalization in male sexual functions. Furthermore, the analysis of the OdsH peptide allowed the identification of mutations of D. mauritiana that could result in incompatibility in hybrids. In order to find if OdsH could be related to hybrid sterility, beyond Sophophora, we explored the expression of OdsH in Drosophila arizonae and Drosophila mojavensis, a pair of sister species with incomplete reproductive isolation. Our data indicated that OdsH expression is not atypical in their male-sterile hybrids. In conclusion, we have proposed that the origin of OdsH occurred earlier than previously proposed, followed by neofunctionalization. Our results also suggested that its role as a speciation gene might be restricted to D. mauritiana and D. simulans.
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Affiliation(s)
- William Vilas Boas Nunes
- Institute of Biosciences, Humanities and Exact Sciences, São Paulo State University (Unesp), 2265 Cristóvão Colombo Street, 15054-000 São José do Rio Preto, Brazil
- Laboratoire de Biométrie et Biologie Evolutive UMR 5558, Université de Lyon, Université Lyon 1, CNRS, Bât. Grégor Mendel, 43 Boulevard 11 Novembre 1918, 69622 Villeurbanne, France
| | - Daniel Siqueira Oliveira
- Institute of Biosciences, Humanities and Exact Sciences, São Paulo State University (Unesp), 2265 Cristóvão Colombo Street, 15054-000 São José do Rio Preto, Brazil
- Laboratoire de Biométrie et Biologie Evolutive UMR 5558, Université de Lyon, Université Lyon 1, CNRS, Bât. Grégor Mendel, 43 Boulevard 11 Novembre 1918, 69622 Villeurbanne, France
| | - Guilherme de Rezende Dias
- Departamento de Genética, Instituto de Biologia, Universidade Federal do Rio de Janeiro, CCS sl A2-075, 373 Carlos Chagas Filho Avenue, 21941-971 Rio de Janeiro, Brazil
| | - Antonio Bernardo Carvalho
- Departamento de Genética, Instituto de Biologia, Universidade Federal do Rio de Janeiro, CCS sl A2-075, 373 Carlos Chagas Filho Avenue, 21941-971 Rio de Janeiro, Brazil
| | - Ícaro Putinhon Caruso
- Institute of Biosciences, Humanities and Exact Sciences, São Paulo State University (Unesp), 2265 Cristóvão Colombo Street, 15054-000 São José do Rio Preto, Brazil
| | - Joice Matos Biselli
- Institute of Biosciences, Humanities and Exact Sciences, São Paulo State University (Unesp), 2265 Cristóvão Colombo Street, 15054-000 São José do Rio Preto, Brazil
| | - Nathalie Guegen
- Faculté de Médecine, iGReD, Université Clermont Auvergne, CNRS, INSERM, 4 Bd Claude Bernard, 63000 Clermont-Ferrande, France
| | - Abdou Akkouche
- Faculté de Médecine, iGReD, Université Clermont Auvergne, CNRS, INSERM, 4 Bd Claude Bernard, 63000 Clermont-Ferrande, France
| | - Nelly Burlet
- Laboratoire de Biométrie et Biologie Evolutive UMR 5558, Université de Lyon, Université Lyon 1, CNRS, Bât. Grégor Mendel, 43 Boulevard 11 Novembre 1918, 69622 Villeurbanne, France
| | - Cristina Vieira
- Laboratoire de Biométrie et Biologie Evolutive UMR 5558, Université de Lyon, Université Lyon 1, CNRS, Bât. Grégor Mendel, 43 Boulevard 11 Novembre 1918, 69622 Villeurbanne, France
| | - Claudia M A Carareto
- Institute of Biosciences, Humanities and Exact Sciences, São Paulo State University (Unesp), 2265 Cristóvão Colombo Street, 15054-000 São José do Rio Preto, Brazil
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44
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Sato A, Yew JY, Takahashi A. Effect of acetic acid bacteria colonization on oviposition and feeding site choice in Drosophila suzukii and its related species. MICROPUBLICATION BIOLOGY 2024; 2024:10.17912/micropub.biology.001111. [PMID: 38404921 PMCID: PMC10884830 DOI: 10.17912/micropub.biology.001111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Figures] [Subscribe] [Scholar Register] [Received: 01/04/2024] [Revised: 01/26/2024] [Accepted: 01/31/2024] [Indexed: 02/27/2024]
Abstract
Unlike many species of Drosophila flies that colonize decaying fruits, Drosophila suzukii lay eggs in ripening fruits. The oviposition and feeding site preferences for bacterial growth were quantified in multiple strains of D. suzukii and its closely related species, D. subpulchrella and D. biarmipes . A continuous degree of preference for oviposition sites with Acetobacter growth both within and across species suggested that the separation in resource usage is notable but not complete among these species. The lack of interspecific differences in feeding site preference for Acetobacter -containing media implied that the oviposition site preferences evolved independently from the feeding site preference.
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Affiliation(s)
- Airi Sato
- Department of Biological Sciences, Tokyo Metropolitan University, Hachioji, Tokyo, Japan
| | - Joanne Y. Yew
- Pacific Biosciences Research Center, University of Hawaiʻi at Mānoa, Honolulu, Hawaii, United States
| | - Aya Takahashi
- Department of Biological Sciences, Tokyo Metropolitan University, Hachioji, Tokyo, Japan
- Research Center for Genomics and Bioinformatics, Tokyo Metropolitan University, Hachioji, Tokyo, Japan
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45
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Bontonou G, Saint-Leandre B, Kafle T, Baticle T, Hassan A, Sánchez-Alcañiz JA, Arguello JR. Evolution of chemosensory tissues and cells across ecologically diverse Drosophilids. Nat Commun 2024; 15:1047. [PMID: 38316749 PMCID: PMC10844241 DOI: 10.1038/s41467-023-44558-4] [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: 05/10/2023] [Accepted: 12/19/2023] [Indexed: 02/07/2024] Open
Abstract
Chemosensory tissues exhibit significant between-species variability, yet the evolution of gene expression and cell types underlying this diversity remain poorly understood. To address these questions, we conducted transcriptomic analyses of five chemosensory tissues from six Drosophila species and integrated the findings with single-cell datasets. While stabilizing selection predominantly shapes chemosensory transcriptomes, thousands of genes in each tissue have evolved expression differences. Genes that have changed expression in one tissue have often changed in multiple other tissues but at different past epochs and are more likely to be cell type-specific than unchanged genes. Notably, chemosensory-related genes have undergone widespread expression changes, with numerous species-specific gains/losses including novel chemoreceptors expression patterns. Sex differences are also pervasive, including a D. melanogaster-specific excess of male-biased expression in sensory and muscle cells in its forelegs. Together, our analyses provide new insights for understanding evolutionary changes in chemosensory tissues at both global and individual gene levels.
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Affiliation(s)
- Gwénaëlle Bontonou
- Department of Ecology & Evolution, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland.
- Swiss Institute of Bioinformatics, Lausanne, Switzerland.
| | - Bastien Saint-Leandre
- Department of Ecology & Evolution, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland.
- Swiss Institute of Bioinformatics, Lausanne, Switzerland.
| | - Tane Kafle
- Department of Ecology & Evolution, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
- Swiss Institute of Bioinformatics, Lausanne, Switzerland
| | - Tess Baticle
- Department of Ecology & Evolution, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| | - Afrah Hassan
- Department of Ecology & Evolution, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| | | | - J Roman Arguello
- Department of Ecology & Evolution, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland.
- Swiss Institute of Bioinformatics, Lausanne, Switzerland.
- School of Biological and Behavioural Sciences, Queen Mary University of London, London, UK.
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46
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Monier M, Nuez I, Borne F, Courtier-Orgogozo V. Higher evolutionary dynamics of gene copy number for Drosophila glue genes located near short repeat sequences. BMC Ecol Evol 2024; 24:18. [PMID: 38308233 PMCID: PMC10835880 DOI: 10.1186/s12862-023-02178-y] [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: 01/19/2023] [Accepted: 11/23/2023] [Indexed: 02/04/2024] Open
Abstract
BACKGROUND During evolution, genes can experience duplications, losses, inversions and gene conversions. Why certain genes are more dynamic than others is poorly understood. Here we examine how several Sgs genes encoding glue proteins, which make up a bioadhesive that sticks the animal during metamorphosis, have evolved in Drosophila species. RESULTS We examined high-quality genome assemblies of 24 Drosophila species to study the evolutionary dynamics of four glue genes that are present in D. melanogaster and are part of the same gene family - Sgs1, Sgs3, Sgs7 and Sgs8 - across approximately 30 millions of years. We annotated a total of 102 Sgs genes and grouped them into 4 subfamilies. We present here a new nomenclature for these Sgs genes based on protein sequence conservation, genomic location and presence/absence of internal repeats. Two types of glue genes were uncovered. The first category (Sgs1, Sgs3x, Sgs3e) showed a few gene losses but no duplication, no local inversion and no gene conversion. The second group (Sgs3b, Sgs7, Sgs8) exhibited multiple events of gene losses, gene duplications, local inversions and gene conversions. Our data suggest that the presence of short "new glue" genes near the genes of the latter group may have accelerated their dynamics. CONCLUSIONS Our comparative analysis suggests that the evolutionary dynamics of glue genes is influenced by genomic context. Our molecular, phylogenetic and comparative analysis of the four glue genes Sgs1, Sgs3, Sgs7 and Sgs8 provides the foundation for investigating the role of the various glue genes during Drosophila life.
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Affiliation(s)
- Manon Monier
- Université Paris Cité, CNRS, Institut Jacques Monod, 75013, Paris, France
| | - Isabelle Nuez
- Université Paris Cité, CNRS, Institut Jacques Monod, 75013, Paris, France
| | - Flora Borne
- Université Paris Cité, CNRS, Institut Jacques Monod, 75013, Paris, France
- Department of Biological Sciences, Columbia University, New York city, New York, USA
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47
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Sperling AL, Glover DM. Aneuploidy during development in facultative parthenogenetic Drosophila. Heredity (Edinb) 2024; 132:89-97. [PMID: 38017115 PMCID: PMC10844303 DOI: 10.1038/s41437-023-00664-z] [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: 07/22/2023] [Revised: 11/10/2023] [Accepted: 11/14/2023] [Indexed: 11/30/2023] Open
Abstract
From concatenated chromosomes to polyploidization, large-scale genome changes are known to occur in parthenogenetic animals. Here, we report mosaic aneuploidy in larval brains of facultatively parthenogenetic Drosophila. We identified a background of aneuploidy in D. mercatorum strains and found increased levels of aneuploidy in the larval brain tissue of animals arising parthenogenetically versus those arising from sexual reproduction. There is also intra-individual variation in germline-derived aneuploidy within the same strain. To determine if this is a general feature of facultative parthenogenesis in drosophilids, we compared sexually reproduced and parthenogenetic offspring from an engineered facultative parthenogenetic strain of D. melanogaster. In addition to germline-derived aneuploidy, this revealed somatic aneuploidy that increased by up to fourfold in parthenogens compared to sexually reproduced offspring. Therefore, the genetic combination identified in D. mercatorum that causes facultative parthenogenesis in D. melanogaster results in aneuploidy, which indicates that the loss of mitotic control resulting in parthenogenesis causes subsequent genome variation within the parthenogenetic offspring. Our findings challenge the assumption that parthenogenetic offspring are near genetic replicas of their mothers.
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Affiliation(s)
- A L Sperling
- Department of Genetics, University of Cambridge, Cambridge, UK.
| | - D M Glover
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA.
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48
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Seto Y, Iwasaki Y, Ogawa Y, Tamura K, Toda MJ. Skeleton phylogeny reconstructed with transcriptomes for the tribe Drosophilini (Diptera: Drosophilidae). Mol Phylogenet Evol 2024; 191:107978. [PMID: 38013068 DOI: 10.1016/j.ympev.2023.107978] [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: 03/18/2023] [Revised: 10/30/2023] [Accepted: 11/23/2023] [Indexed: 11/29/2023]
Abstract
The family Drosophilidae is one of the most important model systems in evolutionary biology. Thanks to advances in high-throughput sequencing technology, a number of molecular phylogenetic analyses have been undertaken by using large data sets of many genes and many species sampled across this family. Especially, recent analyses using genome sequences have depicted the family-wide skeleton phylogeny with high confidence. However, the taxon sampling is still insufficient for minor lineages and non-Drosophila genera. In this study, we carried out phylogenetic analyses using a large number of transcriptome-based nucleotide sequences, focusing on the largest, core tribe Drosophilini in the Drosophilidae. In our analyses, some noise factors against phylogenetic reconstruction were taken into account by removing putative paralogy from the datasets and examining the effects of missing data, i.e. gene occupancy and site coverage, and incomplete lineage sorting. The inferred phylogeny has newly resolved the following phylogenetic positions/relationships at the genomic scale: (i) the monophyly of the subgenus Siphlodora including Zaprionus flavofasciatus to be transferred therein; (ii) the paraphyly of the robusta and melanica species groups within a clade comprised of the robusta, melanica and quadrisetata groups and Z. flavofasciatus; (iii) Drosophila curviceps (representing the curviceps group), D. annulipes (the quadrilineata subgroup of the immigrans group) and D. maculinotata clustered into a clade sister to the Idiomyia + Scaptomyza clade, forming together the expanded Hawaiian drosophilid lineage; (iv) Dichaetophora tenuicauda (representing the lineage comprised of the Zygothrica genus group and Dichaetophora) placed as the sister to the clade of the expanded Hawaiian drosophilid lineage and Siphlodora; and (v) relationships of the subgenus Drosophila and the genus Zaprionus as follows: (Zaprionus, (the quadrilineata subgroup, ((D. sternopleuralis, the immigrans group proper), (the quinaria radiation, the tripunctata radiation)))). These results are to be incorporated into the so-far published phylogenomic tree as a backbone (constraint) tree for grafting much more species based on sequences of a limited number of genes. Such a comprehensive, highly confident phylogenetic tree with extensive and dense taxon sampling will provide an essential framework for comparative studies of the Drosophilidae.
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Affiliation(s)
- Yosuke Seto
- Department of Biological Sciences, Tokyo Metropolitan University, Tokyo, Japan; Division of Experimental Chemotherapy, Cancer Chemotherapy Center, Japanese Foundation for Cancer Research, Tokyo, Japan.
| | - Yuma Iwasaki
- Department of Biological Sciences, Tokyo Metropolitan University, Tokyo, Japan.
| | - Yoshitaka Ogawa
- Department of Biological Sciences, Tokyo Metropolitan University, Tokyo, Japan.
| | - Koichiro Tamura
- Department of Biological Sciences, Tokyo Metropolitan University, Tokyo, Japan; Research Center for Genomics and Bioinformatics, Tokyo Metropolitan University, Tokyo, Japan.
| | - Masanori J Toda
- Hokkaido University Museum, Hokkaido University, Sapporo, Japan.
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49
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Ray DD, Flagel L, Schrider DR. IntroUNET: Identifying introgressed alleles via semantic segmentation. PLoS Genet 2024; 20:e1010657. [PMID: 38377104 PMCID: PMC10906877 DOI: 10.1371/journal.pgen.1010657] [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: 02/06/2023] [Revised: 03/01/2024] [Accepted: 01/29/2024] [Indexed: 02/22/2024] Open
Abstract
A growing body of evidence suggests that gene flow between closely related species is a widespread phenomenon. Alleles that introgress from one species into a close relative are typically neutral or deleterious, but sometimes confer a significant fitness advantage. Given the potential relevance to speciation and adaptation, numerous methods have therefore been devised to identify regions of the genome that have experienced introgression. Recently, supervised machine learning approaches have been shown to be highly effective for detecting introgression. One especially promising approach is to treat population genetic inference as an image classification problem, and feed an image representation of a population genetic alignment as input to a deep neural network that distinguishes among evolutionary models (i.e. introgression or no introgression). However, if we wish to investigate the full extent and fitness effects of introgression, merely identifying genomic regions in a population genetic alignment that harbor introgressed loci is insufficient-ideally we would be able to infer precisely which individuals have introgressed material and at which positions in the genome. Here we adapt a deep learning algorithm for semantic segmentation, the task of correctly identifying the type of object to which each individual pixel in an image belongs, to the task of identifying introgressed alleles. Our trained neural network is thus able to infer, for each individual in a two-population alignment, which of those individual's alleles were introgressed from the other population. We use simulated data to show that this approach is highly accurate, and that it can be readily extended to identify alleles that are introgressed from an unsampled "ghost" population, performing comparably to a supervised learning method tailored specifically to that task. Finally, we apply this method to data from Drosophila, showing that it is able to accurately recover introgressed haplotypes from real data. This analysis reveals that introgressed alleles are typically confined to lower frequencies within genic regions, suggestive of purifying selection, but are found at much higher frequencies in a region previously shown to be affected by adaptive introgression. Our method's success in recovering introgressed haplotypes in challenging real-world scenarios underscores the utility of deep learning approaches for making richer evolutionary inferences from genomic data.
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Affiliation(s)
- Dylan D. Ray
- Department of Genetics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Lex Flagel
- Division of Data Science, Gencove Inc., New York, New York, United States of America
- Department of Plant and Microbial Biology, University of Minnesota, Saint Paul, Minnesota, United States of America
| | - Daniel R. Schrider
- Department of Genetics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
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50
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Ray DD, Flagel L, Schrider DR. IntroUNET: identifying introgressed alleles via semantic segmentation. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.02.07.527435. [PMID: 36865105 PMCID: PMC9979274 DOI: 10.1101/2023.02.07.527435] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
A growing body of evidence suggests that gene flow between closely related species is a widespread phenomenon. Alleles that introgress from one species into a close relative are typically neutral or deleterious, but sometimes confer a significant fitness advantage. Given the potential relevance to speciation and adaptation, numerous methods have therefore been devised to identify regions of the genome that have experienced introgression. Recently, supervised machine learning approaches have been shown to be highly effective for detecting introgression. One especially promising approach is to treat population genetic inference as an image classification problem, and feed an image representation of a population genetic alignment as input to a deep neural network that distinguishes among evolutionary models (i.e. introgression or no introgression). However, if we wish to investigate the full extent and fitness effects of introgression, merely identifying genomic regions in a population genetic alignment that harbor introgressed loci is insufficient-ideally we would be able to infer precisely which individuals have introgressed material and at which positions in the genome. Here we adapt a deep learning algorithm for semantic segmentation, the task of correctly identifying the type of object to which each individual pixel in an image belongs, to the task of identifying introgressed alleles. Our trained neural network is thus able to infer, for each individual in a two-population alignment, which of those individual's alleles were introgressed from the other population. We use simulated data to show that this approach is highly accurate, and that it can be readily extended to identify alleles that are introgressed from an unsampled "ghost" population, performing comparably to a supervised learning method tailored specifically to that task. Finally, we apply this method to data from Drosophila, showing that it is able to accurately recover introgressed haplotypes from real data. This analysis reveals that introgressed alleles are typically confined to lower frequencies within genic regions, suggestive of purifying selection, but are found at much higher frequencies in a region previously shown to be affected by adaptive introgression. Our method's success in recovering introgressed haplotypes in challenging real-world scenarios underscores the utility of deep learning approaches for making richer evolutionary inferences from genomic data.
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Affiliation(s)
- Dylan D. Ray
- Department of Genetics, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Lex Flagel
- Division of Data Science, Gencove Inc., New York, NY 11101, USA
- Department of Plant and Microbial Biology, University of Minnesota, St Paul MN, 55108, USA
| | - Daniel R. Schrider
- Department of Genetics, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
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