1
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Berardi S, Rhodes JA, Berner MC, Greenblum SI, Bitter MC, Behrman EL, Betancourt NJ, Bergland AO, Petrov DA, Rajpurohit S, Schmidt P. Drosophila melanogaster pigmentation demonstrates adaptive phenotypic parallelism but genomic unpredictability over multiple timescales. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.08.09.607378. [PMID: 39211235 PMCID: PMC11361081 DOI: 10.1101/2024.08.09.607378] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/04/2024]
Abstract
Populations are capable of responding to environmental change over ecological timescales via adaptive tracking. However, the translation from patterns of allele frequency change to rapid adaptation of complex traits remains unresolved. We used abdominal pigmentation in Drosophila melanogaster as a model phenotype to address the nature, genetic architecture, and repeatability of rapid adaptation in the field. We show that D. melanogaster pigmentation evolves as a highly parallel and deterministic response to shared environmental gradients across latitude and season in natural North American populations. We then experimentally evolved replicate, genetically diverse fly populations in field mesocosms to remove any confounding effects of demography and/or cryptic structure that may drive patterns in wild populations; we show that pigmentation rapidly responds, in parallel, in fewer than ten generations. Thus, pigmentation evolves concordantly in response to spatial and temporal climatic gradients. We next examined whether phenotypic differentiation was associated with allele frequency change at loci with established links to genetic variance in pigmentation in natural populations. We found that across all spatial and temporal scales, phenotypic patterns were associated with variation at pigmentation-related loci, and the sets of genes we identified in each context were largely nonoverlapping. Therefore, our findings suggest that parallel phenotypic evolution is associated with an unpredictable genomic response, with distinct components of the polygenic architecture shifting across each environmental gradient to produce redundant adaptive patterns. Significance Statement Shifts in global climate conditions have heightened our need to understand the dynamics and pace of adaptation in natural populations. In order to anticipate the population-level response to rapidly changing environmental conditions, we need to understand whether trait evolution is predictable over short timescales, and whether the genetic basis of adaptation is shared or distinct across multiple timescales. Here, we explored parallelism in the adaptive response of a complex phenotype, D. melanogaster pigmentation, to shared conditions that varied over multiple spatiotemporal scales. Our results demonstrate that while phenotypic adaptation proceeds as a predictable response to environmental gradients, even over short timescales, the genetic basis of the adaptive response is variable and nuanced across spatial and temporal contexts.
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2
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Stavenga DG. Butterfly blues and greens caused by subtractive colour mixing of carotenoids and bile pigments. J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2024; 210:371-380. [PMID: 37436440 PMCID: PMC11106126 DOI: 10.1007/s00359-023-01656-4] [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: 05/06/2023] [Revised: 06/29/2023] [Accepted: 06/30/2023] [Indexed: 07/13/2023]
Abstract
Butterflies often have conspicuously patterned wings, due to pigmentary and/or structurally wing scales that cover the wing membrane. The wing membrane of several butterfly species is also pigmentary coloured, notably by the bile pigments pterobilin, pharcobilin and sarpedobilin. The absorption spectra of the bilins have bands in the ultraviolet and red wavelength range, resulting in blue-cyan colours. Here, a survey of papilionoid and nymphalid butterflies reveals that several species with wings containing bile pigments combine them with carotenoids and other short-wavelength absorbing pigments, e.g., papiliochrome II, ommochromes and flavonoids, which creates green-coloured patterns. Various uncharacterized, long-wavelength absorbing wing pigments were encountered, particularly in heliconiines. The wings thus exhibit quite variable reflectance spectra, extending the enormous pigmentary and structural colouration richness of butterflies.
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Affiliation(s)
- Doekele G Stavenga
- Groningen Institute for Evolutionary Life Sciences, University of Groningen, Nijenborgh 7, 9747AG, Groningen, The Netherlands.
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3
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Yang W, Cui J, Chen Y, Wang C, Yin Y, Zhang W, Liu S, Sun C, Li H, Duan Y, Song F, Cai W, Hines HM, Tian L. Genetic Modification of a Hox Locus Drives Mimetic Color Pattern Variation in a Highly Polymorphic Bumble Bee. Mol Biol Evol 2023; 40:msad261. [PMID: 38039153 PMCID: PMC10724181 DOI: 10.1093/molbev/msad261] [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: 09/01/2023] [Revised: 11/11/2023] [Accepted: 11/27/2023] [Indexed: 12/03/2023] Open
Abstract
Müllerian mimicry provides natural replicates ideal for exploring mechanisms underlying adaptive phenotypic divergence and convergence, yet the genetic mechanisms underlying mimetic variation remain largely unknown. The current study investigates the genetic basis of mimetic color pattern variation in a highly polymorphic bumble bee, Bombus breviceps (Hymenoptera, Apidae). In South Asia, this species and multiple comimetic species converge onto local Müllerian mimicry patterns by shifting the abdominal setal color from orange to black. Genetic crossing between the orange and black phenotypes suggested the color dimorphism being controlled by a single Mendelian locus, with the orange allele being dominant over black. Genome-wide association suggests that a locus at the intergenic region between 2 abdominal fate-determining Hox genes, abd-A and Abd-B, is associated with the color change. This locus is therefore in the same intergenic region but not the same exact locus as found to drive red black midabdominal variation in a distantly related bumble bee species, Bombus melanopygus. Gene expression analysis and RNA interferences suggest that differential expression of an intergenic long noncoding RNA between abd-A and Abd-B at the onset setal color differentiation may drive the orange black color variation by causing a homeotic shift late in development. Analysis of this same color locus in comimetic species reveals no sequence association with the same color shift, suggesting that mimetic convergence is achieved through distinct genetic routes. Our study establishes Hox regions as genomic hotspots for color pattern evolution in bumble bees and demonstrates how pleiotropic developmental loci can drive adaptive radiations in nature.
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Affiliation(s)
- Wanhu Yang
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, Beijing 100193, China
| | - Jixiang Cui
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, Beijing 100193, China
| | - Yuxin Chen
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, Beijing 100193, China
| | - Chao Wang
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, Beijing 100193, China
| | - Yuanzhi Yin
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, Beijing 100193, China
| | - Wei Zhang
- State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, Beijing 100871, China
| | - Shanlin Liu
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, Beijing 100193, China
| | - Cheng Sun
- College of Life Sciences, Capital Normal University, Beijing 100048, China
| | - Hu Li
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, Beijing 100193, China
| | - Yuange Duan
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, Beijing 100193, China
| | - Fan Song
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, Beijing 100193, China
| | - Wanzhi Cai
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, Beijing 100193, China
| | - Heather M Hines
- Department of Biology, The Pennsylvania State University, University Park, PA 16802, USA
| | - Li Tian
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, Beijing 100193, China
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4
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Milinkovitch MC, Jahanbakhsh E, Zakany S. The Unreasonable Effectiveness of Reaction Diffusion in Vertebrate Skin Color Patterning. Annu Rev Cell Dev Biol 2023; 39:145-174. [PMID: 37843926 DOI: 10.1146/annurev-cellbio-120319-024414] [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] [Indexed: 10/18/2023]
Abstract
In 1952, Alan Turing published the reaction-diffusion (RD) mathematical framework, laying the foundations of morphogenesis as a self-organized process emerging from physicochemical first principles. Regrettably, this approach has been widely doubted in the field of developmental biology. First, we summarize Turing's line of thoughts to alleviate the misconception that RD is an artificial mathematical construct. Second, we discuss why phenomenological RD models are particularly effective for understanding skin color patterning at the meso/macroscopic scales, without the need to parameterize the profusion of variables at lower scales. More specifically, we discuss how RD models (a) recapitulate the diversity of actual skin patterns, (b) capture the underlying dynamics of cellular interactions, (c) interact with tissue size and shape, (d) can lead to ordered sequential patterning, (e) generate cellular automaton dynamics in lizards and snakes, (f) predict actual patterns beyond their statistical features, and (g) are robust to model variations. Third, we discuss the utility of linear stability analysis and perform numerical simulations to demonstrate how deterministic RD emerges from the underlying chaotic microscopic agents.
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Affiliation(s)
- Michel C Milinkovitch
- Laboratory of Artificial and Natural Evolution, Department of Genetics and Evolution, University of Geneva, Geneva, Switzerland;
| | - Ebrahim Jahanbakhsh
- Laboratory of Artificial and Natural Evolution, Department of Genetics and Evolution, University of Geneva, Geneva, Switzerland;
| | - Szabolcs Zakany
- Laboratory of Artificial and Natural Evolution, Department of Genetics and Evolution, University of Geneva, Geneva, Switzerland;
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5
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Kronforst MR, Sheikh SI. New molecular insights into butterfly pigmentation. Cell Rep 2023; 42:112981. [PMID: 37594895 DOI: 10.1016/j.celrep.2023.112981] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Revised: 07/28/2023] [Accepted: 07/31/2023] [Indexed: 08/20/2023] Open
Abstract
Hanly et al.1 and Nishida et al.2 use distinct approaches to provide exceptional lessons regarding the genetic, molecular, morphological, and biochemical bases of butterfly wing pigmentation. These mechanistic insights collectively have important implications for our understanding of phenotype evolution.
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Affiliation(s)
- Marcus R Kronforst
- Department of Ecology & Evolution, The University of Chicago, Chicago, IL 60637, USA.
| | - Sofia I Sheikh
- Department of Ecology & Evolution, The University of Chicago, Chicago, IL 60637, USA
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6
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Elkin J, Martin A, Courtier-Orgogozo V, Santos ME. Analysis of the genetic loci of pigment pattern evolution in vertebrates. Biol Rev Camb Philos Soc 2023; 98:1250-1277. [PMID: 37017088 DOI: 10.1111/brv.12952] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Revised: 03/08/2023] [Accepted: 03/14/2023] [Indexed: 04/06/2023]
Abstract
Vertebrate pigmentation patterns are amongst the best characterised model systems for studying the genetic basis of adaptive evolution. The wealth of available data on the genetic basis for pigmentation evolution allows for analysis of trends and quantitative testing of evolutionary hypotheses. We employed Gephebase, a database of genetic variants associated with natural and domesticated trait variation, to examine trends in how cis-regulatory and coding mutations contribute to vertebrate pigmentation phenotypes, as well as factors that favour one mutation type over the other. We found that studies with lower ascertainment bias identified higher proportions of cis-regulatory mutations, and that cis-regulatory mutations were more common amongst animals harbouring a higher number of pigment cell classes. We classified pigmentation traits firstly according to their physiological basis and secondly according to whether they affect colour or pattern, and identified that carotenoid-based pigmentation and variation in pattern boundaries are preferentially associated with cis-regulatory change. We also classified genes according to their developmental, cellular, and molecular functions. We found a greater proportion of cis-regulatory mutations in genes implicated in upstream developmental processes compared to those involved in downstream cellular functions, and that ligands were associated with a higher proportion of cis-regulatory mutations than their respective receptors. Based on these trends, we discuss future directions for research in vertebrate pigmentation evolution.
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Affiliation(s)
- Joel Elkin
- Department of Zoology, University of Cambridge, Downing Street, Cambridge, CB2 3EJ, UK
| | - Arnaud Martin
- Department of Biological Sciences, The George Washington University, 800 22nd St. NW, Suite 6000, Washington, DC, 20052, USA
| | | | - M Emília Santos
- Department of Zoology, University of Cambridge, Downing Street, Cambridge, CB2 3EJ, UK
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7
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Hidalgo M, Curantz C, Quenech’Du N, Neguer J, Beck S, Mohammad A, Manceau M. A conserved molecular template underlies color pattern diversity in estrildid finches. SCIENCE ADVANCES 2022; 8:eabm5800. [PMID: 36044564 PMCID: PMC9432839 DOI: 10.1126/sciadv.abm5800] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Accepted: 07/13/2022] [Indexed: 05/05/2023]
Abstract
The color patterns that adorn animals' coats not only exhibit extensive diversity linked to various ecological functions but also display recurrences in geometry, orientation, or body location. How processes of pattern formation shape such phenotypic trends remains a mystery. Here, we surveyed plumage color patterns in passerine finches displaying extreme apparent variation and identified a conserved set of color domains. We linked these domains to putative embryonic skin regions instructed by early developmental tissues and outlined by the combinatory expression of few genetic markers. We found that this embryonic prepattern is largely conserved in birds displaying drastic color differences in the adult, interspecies variation resulting from the masking or display of each domain depending on their coloration. This work showed that a simple molecular landscape serves as common spatial template to extensive color pattern variation in finches, revealing that early conserved landmarks and molecular pathways are a major cause of phenotypic trends.
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Affiliation(s)
- Magdalena Hidalgo
- Center for Interdisciplinary Research in Biology, Collège de France, CNRS, INSERM, Université PSL, Paris, France
| | - Camille Curantz
- Center for Interdisciplinary Research in Biology, Collège de France, CNRS, INSERM, Université PSL, Paris, France
- Sorbonne University, UPMC Paris VI, Paris, France
| | - Nicole Quenech’Du
- Center for Interdisciplinary Research in Biology, Collège de France, CNRS, INSERM, Université PSL, Paris, France
| | - Julia Neguer
- Center for Interdisciplinary Research in Biology, Collège de France, CNRS, INSERM, Université PSL, Paris, France
| | - Samantha Beck
- Center for Interdisciplinary Research in Biology, Collège de France, CNRS, INSERM, Université PSL, Paris, France
| | - Ammara Mohammad
- Genomic Facility, Institute of Biology of the Ecole Normale Supérieure, CNRS, INSERM Paris, France
| | - Marie Manceau
- Center for Interdisciplinary Research in Biology, Collège de France, CNRS, INSERM, Université PSL, Paris, France
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8
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Bosque RJ, Hyseni C, Santos MLG, Rangel E, Da Silva Dias CJ, Hearin JB, Da Silva NJ, Domingos FMCB, Colli GR, Noonan BP. Müllerian mimicry and the coloration patterns of sympatric coral snakes. Biol J Linn Soc Lond 2022. [DOI: 10.1093/biolinnean/blab155] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Abstract
Coral snakes in the genus Micrurus are venomous, aposematic organisms that signal danger to predators through vivid coloration. Previous studies found that they serve as models to several harmless species of Batesian mimics. However, the extent to which Micrurus species engage in Müllerian mimicry remains poorly understood. We integrate detailed morphological and geographical distribution data to investigate if coral snakes are Müllerian mimics. We found that coloration is spatially structured and that Micrurus species tend to be more similar where they co-occur. Though long supposed, we demonstrate for the first time that coral snakes might indeed be Müllerian mimics as they show some convergence in coloration patterns. Additionally, we found that the length of red-coloured rings in Micrurus is conserved, even at large geographic scales. This finding suggests that bright red rings may be under more substantial stabilizing selection than other aspects of coloration and probably function as a generalized signal for deterring predators.
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Affiliation(s)
- Renan Janke Bosque
- Universidade de Brasília, Instituto de Biologia, Departamento de Zoologia, Brasília, Distrito Federal, Brazil
| | - Chaz Hyseni
- Uppsala University, Department of Ecology and Genetics, Uppsala, Uppsala County, Sweden
- USDA Forest Service, Southern Research Station, Center for Bottomland Hardwoods Research, Oxford, Mississippi, USA
| | | | - Eduardo Rangel
- The University of Mississippi, Department of Biology, University, Mississippi, USA
| | - Camila Juliana Da Silva Dias
- Universidade Federal de Mato Grosso, Instituto de Ciências Biológicas e da Saúde, Pontal do Araguaia, Mato Grosso, Brazil
| | - Jacob Beathea Hearin
- The University of Mississippi, Department of Biology, University, Mississippi, USA
| | - Nelson Jorge Da Silva
- Pontifícia Universidade Católica de Goiás, Escola de Ciências Médicas e da Vida, Goiânia, Goías, Brazil
| | | | - Guarino Rinaldi Colli
- Universidade de Brasília, Instituto de Biologia, Departamento de Zoologia, Brasília, Distrito Federal, Brazil
| | - Brice Patrick Noonan
- The University of Mississippi, Department of Biology, University, Mississippi, USA
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9
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Stervander M, Cresko WA. A highly contiguous nuclear genome assembly of the mandarinfish Synchiropus splendidus (Syngnathiformes: Callionymidae). G3 (BETHESDA, MD.) 2021; 11:jkab306. [PMID: 34849773 PMCID: PMC8664458 DOI: 10.1093/g3journal/jkab306] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/29/2021] [Accepted: 08/23/2021] [Indexed: 12/21/2022]
Abstract
The fish order Syngnathiformes has been referred to as a collection of misfit fishes, comprising commercially important fish such as red mullets as well as the highly diverse seahorses, pipefishes, and seadragons-the well-known family Syngnathidae, with their unique adaptations including male pregnancy. Another ornate member of this order is the species mandarinfish. No less than two types of chromatophores have been discovered in the spectacularly colored mandarinfish: the cyanophore (producing blue color) and the dichromatic cyano-erythrophore (producing blue and red). The phylogenetic position of mandarinfish in Syngnathiformes, and their promise of additional genetic discoveries beyond the chromatophores, made mandarinfish an appealing target for whole-genome sequencing. We used linked sequences to create synthetic long reads, producing a highly contiguous genome assembly for the mandarinfish. The genome assembly comprises 483 Mbp (longest scaffold 29 Mbp), has an N50 of 12 Mbp, and an L50 of 14 scaffolds. The assembly completeness is also high, with 92.6% complete, 4.4% fragmented, and 2.9% missing out of 4584 BUSCO genes found in ray-finned fishes. Outside the family Syngnathidae, the mandarinfish represents one of the most contiguous syngnathiform genome assemblies to date. The mandarinfish genomic resource will likely serve as a high-quality outgroup to syngnathid fish, and furthermore for research on the genomic underpinnings of the evolution of novel pigmentation.
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Affiliation(s)
- Martin Stervander
- Institute of Ecology and Evolution, University of Oregon, Eugene, OR 97403-5289, USA
| | - William A Cresko
- Institute of Ecology and Evolution, University of Oregon, Eugene, OR 97403-5289, USA
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10
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Massey JH, Li J, Stern DL, Wittkopp PJ. Distinct genetic architectures underlie divergent thorax, leg, and wing pigmentation between Drosophila elegans and D. gunungcola. Heredity (Edinb) 2021; 127:467-474. [PMID: 34537820 PMCID: PMC8551284 DOI: 10.1038/s41437-021-00467-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Accepted: 08/09/2021] [Indexed: 02/07/2023] Open
Abstract
Pigmentation divergence between Drosophila species has emerged as a model trait for studying the genetic basis of phenotypic evolution, with genetic changes contributing to pigmentation differences often mapping to genes in the pigment synthesis pathway and their regulators. These studies of Drosophila pigmentation have tended to focus on pigmentation changes in one body part for a particular pair of species, but changes in pigmentation are often observed in multiple body parts between the same pair of species. The similarities and differences of genetic changes responsible for divergent pigmentation in different body parts of the same species thus remain largely unknown. Here we compare the genetic basis of pigmentation divergence between Drosophila elegans and D. gunungcola in the wing, legs, and thorax. Prior work has shown that regions of the genome containing the pigmentation genes yellow and ebony influence the size of divergent male-specific wing spots between these two species. We find that these same two regions of the genome underlie differences in leg and thorax pigmentation; however, divergent alleles in these regions show differences in allelic dominance and epistasis among the three body parts. These complex patterns of inheritance can be explained by a model of evolution involving tissue-specific changes in the expression of Yellow and Ebony between D. elegans and D. gunungcola.
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Affiliation(s)
- Jonathan H Massey
- Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI, USA
- Janelia Research Campus of the Howard Hughes Medical Institute, Ashburn, VA, USA
| | - Jun Li
- Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI, USA
- Institute of Evolution and Ecology, School of Life Sciences, Central China Normal University, Wuhan, China
| | - David L Stern
- Janelia Research Campus of the Howard Hughes Medical Institute, Ashburn, VA, USA
| | - Patricia J Wittkopp
- Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI, USA.
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI, USA.
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11
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Janssen K, Bustnes JO, Mundy NI. Variation in Genetic Mechanisms for Plumage Polymorphism in Skuas (Stercorarius). J Hered 2021; 112:430-435. [PMID: 34343335 PMCID: PMC8634071 DOI: 10.1093/jhered/esab038] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Accepted: 06/28/2021] [Indexed: 11/13/2022] Open
Abstract
Coloration is evolutionarily labile and so provides an excellent trait for examining the repeatability of evolution. Here, we investigate the repeatability of the evolution of polymorphic variation in ventral plumage coloration in skuas (Stercorarius: Stercorariidae). In 2 species, arctic (S. parasiticus) and pomarine skuas (S. pomarinus), plumage polymorphism was previously shown to be associated with coding changes at the melanocortin-1 receptor (MC1R) locus. Here, we show that polymorphism in a third species, the south polar skua (S. maccormicki), is not associated with coding variation at MC1R or with variation at a Z-linked second candidate locus, tyrosinase-related protein 1 (TYRP1). Hence, convergent evolution of plumage polymorphisms in skuas is only partly repeatable at the level of the genetic locus involved. Interestingly, the pattern of repeatability in skuas is aligned not with phylogeny but with the nature of the phenotypic variation. In particular, south polar skuas show a strong sex bias to coloration that is absent in the other species, and it may be that this has a unique genetic architecture.
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Affiliation(s)
- Kirstin Janssen
- Department of Natural Sciences, Tromsø University Museum, NO-9037 Tromsø, Norway.,Centre of Forensic Genetics, Institute of Medical Biology, Faculty of Health Sciences, UIT The Arctic University of Norway, NO-9037 Tromsø, Norway
| | - Jan Ove Bustnes
- Norwegian Institute for Nature Research, The Fram Centre, NO-9296 Tromsø,Norway
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12
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Rahman SR, Terranova T, Tian L, Hines HM. Developmental Transcriptomics Reveals a Gene Network Driving Mimetic Color Variation in a Bumble Bee. Genome Biol Evol 2021; 13:6244266. [PMID: 33881508 PMCID: PMC8220310 DOI: 10.1093/gbe/evab080] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/10/2021] [Indexed: 11/24/2022] Open
Abstract
A major goal of evolutionary genetics and evo-devo is to understand how changes in genotype manifest as changes in phenotype. Bumble bees display remarkable color pattern diversity while converging onto numerous regional Müllerian mimicry patterns, thus enabling exploration of the genetic mechanisms underlying convergent phenotypic evolution. In western North America, multiple bumble bee species converge onto local mimicry patterns through parallel shifts of midabdominal segments from red to black. It was previously demonstrated that a Hox gene, Abd-B, is the key regulator of the phenotypic switch in one of these species, Bombus melanopygus, however, the mechanism by which Abd-B regulates color differentiation remains unclear. Using tissue/stage-specific transcriptomic analysis followed by qRT–PCR validation, this study reveals a suite of genes potentially involved downstream of Abd-B during color pattern differentiation. The data support differential genes expression of not only the first switch gene Abd-B, but also an intermediate developmental gene nubbin, and a whole suite of downstream melanin and redox genes that together reinforce the observed eumelanin (black)-pheomelanin (red) ratios. These include potential genes involved in the production of insect pheomelanins, a pigment until recently not thought to occur in insects and thus lacking known regulatory enzymes. The results enhance understanding of pigmentation gene networks involved in bumble bee color pattern development and diversification, while providing insights into how upstream regulators such as Hox genes interact with downstream morphogenic players to facilitate this adaptive phenotypic radiation.
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Affiliation(s)
- Sarthok Rasique Rahman
- Department of Biology, The Pennsylvania State University, University Park, Pennsylvania, USA.,Department of Biological Sciences, The University of Alabama, Tuscaloosa, Alabama, USA
| | - Tatiana Terranova
- Department of Biology, The Pennsylvania State University, University Park, Pennsylvania, USA
| | - Li Tian
- Department of Entomology, China Agricultural University, Beijing, China
| | - Heather M Hines
- Department of Biology, The Pennsylvania State University, University Park, Pennsylvania, USA.,Department of Entomology, The Pennsylvania State University, University Park, Pennsylvania, USA
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13
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Rahman SR, Cnaani J, Kinch LN, Grishin NV, Hines HM. A combined RAD-Seq and WGS approach reveals the genomic basis of yellow color variation in bumble bee Bombus terrestris. Sci Rep 2021; 11:7996. [PMID: 33846496 PMCID: PMC8042027 DOI: 10.1038/s41598-021-87194-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Accepted: 03/22/2021] [Indexed: 12/30/2022] Open
Abstract
Bumble bees exhibit exceptional diversity in their segmental body coloration largely as a result of mimicry. In this study we sought to discover genes involved in this variation through studying a lab-generated mutant in bumble bee Bombus terrestris, in which the typical black coloration of the pleuron, scutellum, and first metasomal tergite is replaced by yellow, a color variant also found in sister lineages to B. terrestris. Utilizing a combination of RAD-Seq and whole-genome re-sequencing, we localized the color-generating variant to a single SNP in the protein-coding sequence of transcription factor cut. This mutation generates an amino acid change that modifies the conformation of a coiled-coil structure outside DNA-binding domains. We found that all sequenced Hymenoptera, including sister lineages, possess the non-mutant allele, indicating different mechanisms are involved in the same color transition in nature. Cut is important for multiple facets of development, yet this mutation generated no noticeable external phenotypic effects outside of setal characteristics. Reproductive capacity was reduced, however, as queens were less likely to mate and produce female offspring, exhibiting behavior similar to that of workers. Our research implicates a novel developmental player in pigmentation, and potentially caste, thus contributing to a better understanding of the evolution of diversity in both of these processes.
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Affiliation(s)
- Sarthok Rasique Rahman
- Department of Biology, The Pennsylvania State University, 208 Mueller Labs, University Park, PA, USA
- Department of Biological Sciences, The University of Alabama, Tuscaloosa, AL, 35487, USA
| | | | - Lisa N Kinch
- Howard Hughes Medical Institute and Departments of Biophysics and Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Nick V Grishin
- Howard Hughes Medical Institute and Departments of Biophysics and Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Heather M Hines
- Department of Biology, The Pennsylvania State University, 208 Mueller Labs, University Park, PA, USA.
- Department of Entomology, The Pennsylvania State University, University Park, PA, USA.
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14
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Clerbaux LA, Schultz H, Roman-Holba S, Ruan DF, Yu R, Lamb AM, Bommer GT, Kennell JA. The microRNA miR-33 is a pleiotropic regulator of metabolic and developmental processes in Drosophila melanogaster. Dev Dyn 2021; 250:1634-1650. [PMID: 33840153 DOI: 10.1002/dvdy.344] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 03/31/2021] [Accepted: 04/06/2021] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND miR-33 family members are well characterized regulators of cellular lipid levels in mammals. Previous studies have shown that overexpression of miR-33 in Drosophila melanogaster leads to elevated triacylglycerol (TAG) levels in certain contexts. Although loss of miR-33 in flies causes subtle defects in larval and adult ovaries, the effects of miR-33 deficiency on lipid metabolism and other phenotypes impacted by metabolic state have not yet been characterized. RESULTS We found that loss of miR-33 predisposes flies to elevated TAG levels, and we identified genes involved in TAG synthesis as direct targets of miR-33, including atpcl, midway, and Akt1. miR-33 mutants survived longer upon starvation but showed greater sensitivity to an oxidative stressor. We also found evidence that miR-33 is a negative regulator of cuticle pigmentation and that miR-33 mutants show a reduction in interfollicular stalk cells during oogenesis. CONCLUSION Our data suggest that miR-33 is a conserved regulator of lipid homeostasis, and its targets are involved in both degradation and synthesis of fatty acids and TAG. The constellation of phenotypes involving tissues that are highly sensitive to metabolic state suggests that miR-33 serves to prevent extreme fluctuations in metabolically sensitive tissues.
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Affiliation(s)
- Laure-Alix Clerbaux
- Laboratory of Physiological Chemistry, de Duve Institute, Université Catholique de Louvain, Bruxelles, Belgium.,Department of Biology and Program in Biochemistry, Vassar College, Poughkeepsie, New York, USA
| | - Hayley Schultz
- Department of Biology and Program in Biochemistry, Vassar College, Poughkeepsie, New York, USA
| | - Samara Roman-Holba
- Department of Biology and Program in Biochemistry, Vassar College, Poughkeepsie, New York, USA
| | - Dan Fu Ruan
- Department of Biology and Program in Biochemistry, Vassar College, Poughkeepsie, New York, USA
| | - Ronald Yu
- Department of Biology and Program in Biochemistry, Vassar College, Poughkeepsie, New York, USA
| | - Abigail M Lamb
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, Michigan, USA
| | - Guido T Bommer
- Laboratory of Physiological Chemistry, de Duve Institute, Université Catholique de Louvain, Bruxelles, Belgium
| | - Jennifer A Kennell
- Department of Biology and Program in Biochemistry, Vassar College, Poughkeepsie, New York, USA
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15
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Waters CD, Clemento A, Aykanat T, Garza JC, Naish KA, Narum S, Primmer CR. Heterogeneous genetic basis of age at maturity in salmonid fishes. Mol Ecol 2021; 30:1435-1456. [PMID: 33527498 DOI: 10.1111/mec.15822] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Revised: 11/07/2020] [Accepted: 01/11/2021] [Indexed: 12/12/2022]
Abstract
Understanding the genetic basis of repeated evolution of the same phenotype across taxa is a fundamental aim in evolutionary biology and has applications in conservation and management. However, the extent to which interspecific life-history trait polymorphisms share evolutionary pathways remains underexplored. Here, we address this gap by studying the genetic basis of a key life-history trait, age at maturity, in four species of Pacific salmonids (genus Oncorhynchus) that exhibit intra- and interspecific variation in this trait-Chinook Salmon, Coho Salmon, Sockeye Salmon, and Steelhead Trout. We tested for associations in all four species between age at maturity and two genome regions, six6 and vgll3, that are strongly associated with the same trait in Atlantic Salmon (Salmo salar). We also conducted a genome-wide association analysis in Steelhead to assess whether additional regions were associated with this trait. We found the genetic basis of age at maturity to be heterogeneous across salmonid species. Significant associations between six6 and age at maturity were observed in two of the four species, Sockeye and Steelhead, with the association in Steelhead being particularly strong in both sexes (p = 4.46 × 10-9 after adjusting for genomic inflation). However, no significant associations were detected between age at maturity and the vgll3 genome region in any of the species, despite its strong association with the same trait in Atlantic Salmon. We discuss possible explanations for the heterogeneous nature of the genetic architecture of this key life-history trait, as well as the implications of our findings for conservation and management.
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Affiliation(s)
- Charles D Waters
- School of Aquatic and Fishery Sciences, University of Washington, Seattle, WA, USA
| | - Anthony Clemento
- Institute of Marine Sciences, University of California, Santa Cruz, CA, USA.,Santa Cruz Laboratory, Southwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, Santa Cruz, CA, USA
| | - Tutku Aykanat
- Organismal and Evolutionary Biology Research Programme, University of Helsinki, Helsinki, Finland
| | - John Carlos Garza
- Institute of Marine Sciences, University of California, Santa Cruz, CA, USA.,Santa Cruz Laboratory, Southwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, Santa Cruz, CA, USA
| | - Kerry A Naish
- School of Aquatic and Fishery Sciences, University of Washington, Seattle, WA, USA
| | - Shawn Narum
- Hagerman Genetics Laboratory, Columbia River Inter-Tribal Fish Commission, Hagerman, ID, USA
| | - Craig R Primmer
- Organismal and Evolutionary Biology Research Programme, University of Helsinki, Helsinki, Finland.,Institute of Biotechnology, University of Helsinki, Helsinki, Finland
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16
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Molecular and evolutionary processes generating variation in gene expression. Nat Rev Genet 2020; 22:203-215. [PMID: 33268840 DOI: 10.1038/s41576-020-00304-w] [Citation(s) in RCA: 114] [Impact Index Per Article: 28.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/21/2020] [Indexed: 12/18/2022]
Abstract
Heritable variation in gene expression is common within and between species. This variation arises from mutations that alter the form or function of molecular gene regulatory networks that are then filtered by natural selection. High-throughput methods for introducing mutations and characterizing their cis- and trans-regulatory effects on gene expression (particularly, transcription) are revealing how different molecular mechanisms generate regulatory variation, and studies comparing these mutational effects with variation seen in the wild are teasing apart the role of neutral and non-neutral evolutionary processes. This integration of molecular and evolutionary biology allows us to understand how the variation in gene expression we see today came to be and to predict how it is most likely to evolve in the future.
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17
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Shen CH, Xu QY, Fu KY, Guo WC, Jin L, Li GQ. Two Splice Isoforms of Leptinotarsa Ecdysis Triggering Hormone Receptor Have Distinct Roles in Larva-Pupa Transition. Front Physiol 2020; 11:593962. [PMID: 33335488 PMCID: PMC7736071 DOI: 10.3389/fphys.2020.593962] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Accepted: 11/11/2020] [Indexed: 12/13/2022] Open
Abstract
Insect ecdysis triggering hormone (ETH) receptors (ETHRs) are rhodopsin-like G protein-coupled receptors. Upon binding its ligand ETH, ETHR initiates a precisely programed ecdysis behavior series and physiological events. In Drosophila melanogaster, the ethr gene produces two functionally distinct splicing isoforms, ethra and ethrb. ETH/ETHRA activates eclosion hormone (EH), kinin, crustacean cardioactive peptide (CCAP), and bursicon (burs and pburs) neurons, among others, in a rigid order, to elicit the behavioral sequences and physiological actions for ecdysis at all developmental stages, whereas ETH/ETHRB is required at both pupal and adult ecdysis. However, the role of ETHRB in regulation of molting has not been clarified in any non-drosophila insects. In the present paper, we found that 20-hydroxyecdysone (20E) signaling triggers the expression of both ethra and ethrb in a Coleopteran insect pest, the Colorado potato beetle Leptinotarsa decemlineata. RNA interference (RNAi) was performed using double-stranded RNAs (dsRNAs) targeting the common (dsethr) or isoform-specific (dsethra, dsethrb) regions of ethr. RNAi of dsethr, dsethra, or dsethrb by the final-instar larvae arrested larva development. The arrest was not rescued by feeding 20E. All the ethra depleted larvae stopped development at prepupae stage; the body cavity was expanded by a large amount of liquid. Comparably, more than 80% of the ethrb RNAi larvae developmentally halted at the prepupae stage. The remaining Ldethrb hypomorphs became pupae, with blackened wings and highly-expressed burs, pburs and four melanin biosynthesis genes. Therefore, ETHRA and ETHRB play isoform-specific roles in regulation of ecdysis during larva-pupa transition in L. decemlineata.
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Affiliation(s)
- Chen-Hui Shen
- Education Ministry Key Laboratory of Integrated Management of Crop Diseases and Pests, College of Plant Protection, Nanjing Agricultural University, Nanjing, China
| | - Qing-Yu Xu
- Education Ministry Key Laboratory of Integrated Management of Crop Diseases and Pests, College of Plant Protection, Nanjing Agricultural University, Nanjing, China
| | - Kai-Yun Fu
- Institute of Plant Protection, Xinjiang Academy of Agricultural Sciences, Urumqi, China
| | - Wen-Chao Guo
- Institute of Microbiological Application, Xinjiang Academy of Agricultural Science, Urumqi, China
| | - Lin Jin
- Education Ministry Key Laboratory of Integrated Management of Crop Diseases and Pests, College of Plant Protection, Nanjing Agricultural University, Nanjing, China
| | - Guo-Qing Li
- Education Ministry Key Laboratory of Integrated Management of Crop Diseases and Pests, College of Plant Protection, Nanjing Agricultural University, Nanjing, China
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18
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Kuriyama T, Murakami A, Brandley M, Hasegawa M. Blue, Black, and Stripes: Evolution and Development of Color Production and Pattern Formation in Lizards and Snakes. Front Ecol Evol 2020. [DOI: 10.3389/fevo.2020.00232] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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19
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Lamb AM, Wang Z, Simmer P, Chung H, Wittkopp PJ. ebony Affects Pigmentation Divergence and Cuticular Hydrocarbons in Drosophila americana and D. novamexicana. Front Ecol Evol 2020; 8. [PMID: 37035752 PMCID: PMC10077920 DOI: 10.3389/fevo.2020.00184] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Drosophila pigmentation has been a fruitful model system for understanding the genetic and developmental mechanisms underlying phenotypic evolution. For example, prior work has shown that divergence of the tan gene contributes to pigmentation differences between two members of the virilis group: Drosophila novamexicana, which has a light yellow body color, and D. americana, which has a dark brown body color. Quantitative trait locus (QTL) mapping and expression analysis has suggested that divergence of the ebony gene might also contribute to pigmentation differences between these two species. Here, we directly test this hypothesis by using CRISPR/Cas9 genome editing to generate ebony null mutants in D. americana and D. novamexicana and then using reciprocal hemizygosity testing to compare the effects of each species' ebony allele on pigmentation. We find that divergence of ebony does indeed contribute to the pigmentation divergence between species, with effects on both the overall body color as well as a difference in pigmentation along the dorsal abdominal midline. Motivated by recent work in D. melanogaster, we also used the ebony null mutants to test for effects of ebony on cuticular hydrocarbon (CHC) profiles. We found that ebony affects CHC abundance in both species, but does not contribute to qualitative differences in the CHC profiles between these two species. Additional transgenic resources for working with D. americana and D. novamexicana, such as white mutants of both species and yellow mutants in D. novamexicana, were generated in the course of this work and are also described. Taken together, this study advances our understanding of loci contributing to phenotypic divergence and illustrates how the latest genome editing tools can be used for functional testing in non-model species.
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Affiliation(s)
- Abigail M. Lamb
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI, United States
| | - Zinan Wang
- Department of Entomology, Michigan State University, East Lansing, MI, United States
- Ecology, Evolutionary Biology, and Behavior Program, Michigan State University, East Lansing, MI, United States
| | - Patricia Simmer
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI, United States
| | - Henry Chung
- Department of Entomology, Michigan State University, East Lansing, MI, United States
- Ecology, Evolutionary Biology, and Behavior Program, Michigan State University, East Lansing, MI, United States
| | - Patricia J. Wittkopp
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI, United States
- Department of Ecology and Evolutionary Biology, and Behavior Program, University of Michigan, Ann Arbor, MI, United States
- Correspondence: Patricia J Wittkopp,
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20
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Kowalczyk A, Meyer WK, Partha R, Mao W, Clark NL, Chikina M. RERconverge: an R package for associating evolutionary rates with convergent traits. Bioinformatics 2020; 35:4815-4817. [PMID: 31192356 DOI: 10.1093/bioinformatics/btz468] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Revised: 04/08/2019] [Accepted: 06/06/2019] [Indexed: 11/15/2022] Open
Abstract
MOTIVATION When different lineages of organisms independently adapt to similar environments, selection often acts repeatedly upon the same genes, leading to signatures of convergent evolutionary rate shifts at these genes. With the increasing availability of genome sequences for organisms displaying a variety of convergent traits, the ability to identify genes with such convergent rate signatures would enable new insights into the molecular basis of these traits. RESULTS Here we present the R package RERconverge, which tests for association between relative evolutionary rates of genes and the evolution of traits across a phylogeny. RERconverge can perform associations with binary and continuous traits, and it contains tools for visualization and enrichment analyses of association results. AVAILABILITY AND IMPLEMENTATION RERconverge source code, documentation and a detailed usage walk-through are freely available at https://github.com/nclark-lab/RERconverge. Datasets for mammals, Drosophila and yeast are available at https://bit.ly/2J2QBnj. SUPPLEMENTARY INFORMATION Supplementary data are available at Bioinformatics online.
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Affiliation(s)
- Amanda Kowalczyk
- Department of Computational and Systems Biology, University of Pittsburgh, Pittsburgh, PA 15213, USA.,Joint Carnegie Mellon University-University of Pittsburgh Ph.D. Program in Computational Biology, Pittsburgh, PA 15213, USA
| | - Wynn K Meyer
- Department of Computational and Systems Biology, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Raghavendran Partha
- Department of Computational and Systems Biology, University of Pittsburgh, Pittsburgh, PA 15213, USA.,Joint Carnegie Mellon University-University of Pittsburgh Ph.D. Program in Computational Biology, Pittsburgh, PA 15213, USA
| | - Weiguang Mao
- Department of Computational and Systems Biology, University of Pittsburgh, Pittsburgh, PA 15213, USA.,Joint Carnegie Mellon University-University of Pittsburgh Ph.D. Program in Computational Biology, Pittsburgh, PA 15213, USA
| | - Nathan L Clark
- Department of Computational and Systems Biology, University of Pittsburgh, Pittsburgh, PA 15213, USA.,Joint Carnegie Mellon University-University of Pittsburgh Ph.D. Program in Computational Biology, Pittsburgh, PA 15213, USA
| | - Maria Chikina
- Department of Computational and Systems Biology, University of Pittsburgh, Pittsburgh, PA 15213, USA.,Joint Carnegie Mellon University-University of Pittsburgh Ph.D. Program in Computational Biology, Pittsburgh, PA 15213, USA
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21
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VanKuren NW, Massardo D, Nallu S, Kronforst MR. Butterfly Mimicry Polymorphisms Highlight Phylogenetic Limits of Gene Reuse in the Evolution of Diverse Adaptations. Mol Biol Evol 2020; 36:2842-2853. [PMID: 31504750 DOI: 10.1093/molbev/msz194] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Some genes have repeatedly been found to control diverse adaptations in a wide variety of organisms. Such gene reuse reveals not only the diversity of phenotypes these unique genes control but also the composition of developmental gene networks and the genetic routes available to and taken by organisms during adaptation. However, the causes of gene reuse remain unclear. A small number of large-effect Mendelian loci control a huge diversity of mimetic butterfly wing color patterns, but reasons for their reuse are difficult to identify because the genetic basis of mimicry has primarily been studied in two systems with correlated factors: female-limited Batesian mimicry in Papilio swallowtails (Papilionidae) and non-sex-limited Müllerian mimicry in Heliconius longwings (Nymphalidae). Here, we break the correlation between phylogenetic relationship and sex-limited mimicry by identifying loci controlling female-limited mimicry polymorphism Hypolimnas misippus (Nymphalidae) and non-sex-limited mimicry polymorphism in Papilio clytia (Papilionidae). The Papilio clytia polymorphism is controlled by the genome region containing the gene cortex, the classic P supergene in Heliconius numata, and loci controlling color pattern variation across Lepidoptera. In contrast, female-limited mimicry polymorphism in Hypolimnas misippus is associated with a locus not previously implicated in color patterning. Thus, although many species repeatedly converged on cortex and its neighboring genes over 120 My of evolution of diverse color patterns, female-limited mimicry polymorphisms each evolved using a different gene. Our results support conclusions that gene reuse occurs mainly within ∼10 My and highlight the puzzling diversity of genes controlling seemingly complex female-limited mimicry polymorphisms.
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Affiliation(s)
| | - Darli Massardo
- Department of Ecology & Evolution, The University of Chicago, Chicago, IL
| | - Sumitha Nallu
- Department of Ecology & Evolution, The University of Chicago, Chicago, IL
| | - Marcus R Kronforst
- Department of Ecology & Evolution, The University of Chicago, Chicago, IL
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22
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McGaugh SE, Weaver S, Gilbertson EN, Garrett B, Rudeen ML, Grieb S, Roberts J, Donny A, Marchetto P, Gluesenkamp AG. Evidence for rapid phenotypic and behavioural shifts in a recently established cavefish population. Biol J Linn Soc Lond 2019. [DOI: 10.1093/biolinnean/blz162] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Abstract
Cave colonization offers a natural laboratory to study an extreme environmental shift, and diverse cave species from around the world often have converged on robust morphological, physiological and behavioural traits. The Mexican tetra (Astyanax mexicanus) has repeatedly colonized caves in the Sierra de El Abra and Sierra de Guatemala regions of north-east Mexico ~0.20–1 Mya, indicating an ability to adapt to the cave environment. The time frame for the evolution of these traits in any cave animal, however, is poorly understood. Astyanax mexicanus from the Río Grande in South Texas were brought to Central Texas beginning in the early 1900s and colonized underground environments. Here, we investigate whether phenotypic and behavioural differences have occurred rapidly between a surface population and a geographically proximate cave population, probably of recent origin. Fish from the cave and surface populations differ significantly in morphological traits, including coloration, lateral line expansion and dorsal fin placement. Striking behavioural shifts in aggression, feeding and wall-following have also occurred. Together, our results suggest that morphological and behavioural changes accompanying cave colonization can be established rapidly, and this system offers an exciting and unique opportunity for isolating the genetic and environmental contributions to colonization of extreme environments.
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Affiliation(s)
- Suzanne E McGaugh
- Ecology, Evolution, and Behavior, University of Minnesota, Saint Paul, MN, USA
| | - Sam Weaver
- Ecology, Evolution, and Behavior, University of Minnesota, Saint Paul, MN, USA
| | - Erin N Gilbertson
- Ecology, Evolution, and Behavior, University of Minnesota, Saint Paul, MN, USA
| | - Brianna Garrett
- Ecology, Evolution, and Behavior, University of Minnesota, Saint Paul, MN, USA
| | - Melissa L Rudeen
- Ecology, Evolution, and Behavior, University of Minnesota, Saint Paul, MN, USA
| | - Stephanie Grieb
- Ecology, Evolution, and Behavior, University of Minnesota, Saint Paul, MN, USA
| | - Jennifer Roberts
- Ecology, Evolution, and Behavior, University of Minnesota, Saint Paul, MN, USA
| | - Alexandra Donny
- Ecology, Evolution, and Behavior, University of Minnesota, Saint Paul, MN, USA
| | - Peter Marchetto
- Department of Bioproducts and Biosystems Engineering, University of Minnesota, Saint Paul, MN, USA
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23
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Quantitation of eumelanin and pheomelanin markers in diverse biological samples by HPLC-UV-MS following solid-phase extraction. PLoS One 2019; 14:e0223552. [PMID: 31622353 PMCID: PMC6797180 DOI: 10.1371/journal.pone.0223552] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Accepted: 09/24/2019] [Indexed: 01/02/2023] Open
Abstract
Eumelanin and pheomelanin are well known and common pigments found in nature. However, their complex polymer structure and high thermostability complicate their direct chemical identification. A widely used analytical method is indirect determination using HPLC with UV detection of both types of melanin by their most abundant oxidation products: pyrrole-2,3-dicarboxylic acid (PDCA), pyrrole-2,3,5-tricarboxylic acid (PTCA), thiazole-4,5-dicarboxylic acid (TDCA), and thiazole-2,4,5-tricarboxylic acid (TTCA). An increasing interest in pigmentation in biological research led us to develop a highly sensitive and selective method to identify and quantify these melanin markers in diverse biological samples with complex matrices. By introducing solid-phase extraction (SPE, reversed-phase) following alkaline oxidation we could significantly decrease background signals while maintaining recoveries greater than 70%. Our HPLC-UV-MS method allows for confident peak identification via exact mass information in corresponding UV signals used for quantitation. In addition to synthetic melanin and Sepia officinalis ink as reference compounds eumelanin markers were detected in brown human hair and a brown bivalve shell (Mytilus edulis). Brown feathers from the common chicken (Gallus g. domesticus) yielded all four eumelanin and pheomelanin markers. The present method can be easily adapted for a wide range of future studies on biological samples with unknown melanin content.
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24
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Ding X, Liu J, Tong X, Wu S, Li C, Song J, Hu H, Tan D, Dai F. Comparative analysis of integument transcriptomes identifies genes that participate in marking pattern formation in three allelic mutants of silkworm, Bombyx mori. Funct Integr Genomics 2019; 20:223-235. [PMID: 31478115 PMCID: PMC7018788 DOI: 10.1007/s10142-019-00708-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2018] [Revised: 08/04/2019] [Accepted: 08/08/2019] [Indexed: 11/26/2022]
Abstract
The diversity markings and pigment patterns in insects are outcomes of adaptive evolution. The elucidation of the molecular mechanism underlying variations in pigment patterns may improve our understanding of the origin and evolution of these spectacular diverse phenotypes. Melanin, ommochrome, and pteridine are the three main types of insect pigments, and the genes that directly participate in pigment biosynthesis have been extensively studied. However, available information on gene interactions and the whole pigment regulatory network is limited. In this study, we performed integument transcriptome sequencing to analyze three larval marking allelic mutants, namely, multi lunar (L), LC, and LCa, which have similar twin-spot markings on the dorsal side of multiple segments. Further analysis identified 336 differentially expressed genes (DEGs) between L and Dazao (wild type which exhibits normal markings), 68 DEGs between LC/+ and +LC/+LC, and 188 DEGs between LCa/+ and +LCa/+LCa. Gene Ontology (GO) analysis indicated a significant DEG enrichment of the functional terms catalytic activity, binding, metabolic process, and cellular process. Furthermore, three mutants share six common enriched KEGG pathways. We finally identified eight common DEGs among three pairwise comparisons, including Krueppel-like factor, TATA-binding protein, protein patched, UDP-glycosyltransferase, an unknown secreted protein, and three cuticular proteins. Microarray-based gene expression analysis revealed that the eight genes are upregulated during molting, which coincides with marking formation, and are significantly differentially expressed between marking and non-marking regions. The results suggest that the eight common genes are involved in the construction of the multiple twin-spot marking patterns in the three mutants.
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Affiliation(s)
- Xin Ding
- State Key Laboratory of Silkworm Genome Biology, Key Laboratory of Sericultural Biology and Genetic Breeding, Ministry of Agriculture and Rural Affairs, College of Biotechnology, Southwest University, Chongqing, 400715, China
| | - Junxia Liu
- State Key Laboratory of Silkworm Genome Biology, Key Laboratory of Sericultural Biology and Genetic Breeding, Ministry of Agriculture and Rural Affairs, College of Biotechnology, Southwest University, Chongqing, 400715, China
| | - Xiaoling Tong
- State Key Laboratory of Silkworm Genome Biology, Key Laboratory of Sericultural Biology and Genetic Breeding, Ministry of Agriculture and Rural Affairs, College of Biotechnology, Southwest University, Chongqing, 400715, China
| | - Songyuan Wu
- State Key Laboratory of Silkworm Genome Biology, Key Laboratory of Sericultural Biology and Genetic Breeding, Ministry of Agriculture and Rural Affairs, College of Biotechnology, Southwest University, Chongqing, 400715, China
| | - Chunlin Li
- State Key Laboratory of Silkworm Genome Biology, Key Laboratory of Sericultural Biology and Genetic Breeding, Ministry of Agriculture and Rural Affairs, College of Biotechnology, Southwest University, Chongqing, 400715, China
| | - Jiangbo Song
- State Key Laboratory of Silkworm Genome Biology, Key Laboratory of Sericultural Biology and Genetic Breeding, Ministry of Agriculture and Rural Affairs, College of Biotechnology, Southwest University, Chongqing, 400715, China
| | - Hai Hu
- State Key Laboratory of Silkworm Genome Biology, Key Laboratory of Sericultural Biology and Genetic Breeding, Ministry of Agriculture and Rural Affairs, College of Biotechnology, Southwest University, Chongqing, 400715, China
| | - Duan Tan
- State Key Laboratory of Silkworm Genome Biology, Key Laboratory of Sericultural Biology and Genetic Breeding, Ministry of Agriculture and Rural Affairs, College of Biotechnology, Southwest University, Chongqing, 400715, China
| | - Fangyin Dai
- State Key Laboratory of Silkworm Genome Biology, Key Laboratory of Sericultural Biology and Genetic Breeding, Ministry of Agriculture and Rural Affairs, College of Biotechnology, Southwest University, Chongqing, 400715, China.
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25
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Mishra M, Rathore V, Sahu S, Sahoo H. The contribution of nanostructures towards the wing patterning of yellow Catopsilia pomona. How it differs from the lime? Microscopy (Oxf) 2019; 68:289-300. [PMID: 30839060 DOI: 10.1093/jmicro/dfz012] [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: 10/30/2018] [Revised: 02/06/2019] [Indexed: 11/12/2022] Open
Abstract
Polyphenism, an adaptation to survive throughout the year, is shown by many butterflies including Catopsilia pomona. With the variation of seasons, different morphs were found. Among all the morphs, lime exists throughout the year whereas the yellow one is available only in the winter season. The current study deciphers the colouration mechanism of yellow morph using various microscopic and spectroscopic techniques. The scanning electron microscopy analysis reveals various types of scales on the dorsal as well as the ventral side. The shape of the cover scale varies from region to region. The fine structural arrangement of the scale like window, ridge, microrib, crossrib and pigments vary throughout the wing. The pigment present in the wing is pterin as evidenced from the shape and its isolation technique. Absorption spectroscopy further confirms the presence of various types of pterin within the wing. Scanning electron microscopy discloses the dense amount of pigments within the wing. The fine structural arrangement of the wing of yellow C. pomona is compared with the yellow region of the lime C. pomona. All together, the current study describes the fine structural arrangement of the wing of yellow C. pomona and the various types of pterin which contribute towards the wing colouration. The advantage of yellow morph over lime is also discussed in this paper.
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Affiliation(s)
- Monalisa Mishra
- Neural Developmental Biology Lab, Department of Life Science, National Institute of Rourkela, Rourkela, Odisha, India
| | - Varsha Rathore
- Neural Developmental Biology Lab, Department of Life Science, National Institute of Rourkela, Rourkela, Odisha, India
| | - Swetapadma Sahu
- Neural Developmental Biology Lab, Department of Life Science, National Institute of Rourkela, Rourkela, Odisha, India
| | - Harekrushna Sahoo
- Biophysical Chemistry Lab, Department of Chemistry, National Institute of Rourkela, Rourkela, Odisha, India
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26
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Lamichhaney S, Card DC, Grayson P, Tonini JFR, Bravo GA, Näpflin K, Termignoni-Garcia F, Torres C, Burbrink F, Clarke JA, Sackton TB, Edwards SV. Integrating natural history collections and comparative genomics to study the genetic architecture of convergent evolution. Philos Trans R Soc Lond B Biol Sci 2019; 374:20180248. [PMID: 31154982 PMCID: PMC6560268 DOI: 10.1098/rstb.2018.0248] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/25/2019] [Indexed: 12/20/2022] Open
Abstract
Evolutionary convergence has been long considered primary evidence of adaptation driven by natural selection and provides opportunities to explore evolutionary repeatability and predictability. In recent years, there has been increased interest in exploring the genetic mechanisms underlying convergent evolution, in part, owing to the advent of genomic techniques. However, the current 'genomics gold rush' in studies of convergence has overshadowed the reality that most trait classifications are quite broadly defined, resulting in incomplete or potentially biased interpretations of results. Genomic studies of convergence would be greatly improved by integrating deep 'vertical', natural history knowledge with 'horizontal' knowledge focusing on the breadth of taxonomic diversity. Natural history collections have and continue to be best positioned for increasing our comprehensive understanding of phenotypic diversity, with modern practices of digitization and databasing of morphological traits providing exciting improvements in our ability to evaluate the degree of morphological convergence. Combining more detailed phenotypic data with the well-established field of genomics will enable scientists to make progress on an important goal in biology: to understand the degree to which genetic or molecular convergence is associated with phenotypic convergence. Although the fields of comparative biology or comparative genomics alone can separately reveal important insights into convergent evolution, here we suggest that the synergistic and complementary roles of natural history collection-derived phenomic data and comparative genomics methods can be particularly powerful in together elucidating the genomic basis of convergent evolution among higher taxa. This article is part of the theme issue 'Convergent evolution in the genomics era: new insights and directions'.
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Affiliation(s)
- Sangeet Lamichhaney
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138, USA
- Museum of Comparative Zoology, Harvard University, Cambridge, MA 02138, USA
| | - Daren C. Card
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138, USA
- Museum of Comparative Zoology, Harvard University, Cambridge, MA 02138, USA
- Department of Biology, University of Texas Arlington, Arlington, TX 76019, USA
| | - Phil Grayson
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138, USA
- Museum of Comparative Zoology, Harvard University, Cambridge, MA 02138, USA
| | - João F. R. Tonini
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138, USA
- Museum of Comparative Zoology, Harvard University, Cambridge, MA 02138, USA
| | - Gustavo A. Bravo
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138, USA
- Museum of Comparative Zoology, Harvard University, Cambridge, MA 02138, USA
| | - Kathrin Näpflin
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138, USA
- Museum of Comparative Zoology, Harvard University, Cambridge, MA 02138, USA
| | - Flavia Termignoni-Garcia
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138, USA
- Museum of Comparative Zoology, Harvard University, Cambridge, MA 02138, USA
| | - Christopher Torres
- Department of Biology, The University of Texas at Austin, Austin, MA 78712, USA
- Department of Geological Sciences, The University of Texas at Austin, Austin, MA 78712, USA
| | - Frank Burbrink
- Department of Herpetology, The American Museum of Natural History, New York, NY 10024, USA
| | - Julia A. Clarke
- Department of Biology, The University of Texas at Austin, Austin, MA 78712, USA
- Department of Geological Sciences, The University of Texas at Austin, Austin, MA 78712, USA
| | | | - Scott V. Edwards
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138, USA
- Museum of Comparative Zoology, Harvard University, Cambridge, MA 02138, USA
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27
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Liu A, He F, Zhou J, Zou Y, Su Z, Gu X. Comparative Transcriptome Analyses Reveal the Role of Conserved Function in Electric Organ Convergence Across Electric Fishes. Front Genet 2019; 10:664. [PMID: 31379927 PMCID: PMC6657706 DOI: 10.3389/fgene.2019.00664] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2019] [Accepted: 06/25/2019] [Indexed: 11/24/2022] Open
Abstract
The independent origins of multiple electric organs (EOs) of fish are fascinating examples of convergent evolution. However, comparative transcriptomics of different electric fish lineages are scarce. In this study, we found that the gene expression of EOs and skeletal muscles from three lineages (Mormyroidea, Siluriformes, and Gymnotiformes) tended to cluster together based on the species of origin, irrespective of the organ from which they are derived. A pairwise comparison of differentially expressed genes (DEGs) revealed that no less than half of shared DEGs exhibited parallel expression differentiation, indicating conserved directionality of differential expression either in or between lineages, but only a few shared DEGs were identified across all focal species. Nevertheless, the functional enrichment analysis of DEGs indicated that there were more parallel gene expression changes at the level of pathways and biological functions. Therefore, we may conclude that there is no parallel evolution of the entire transcriptomes of EOs among different lineages. Further, our results support the hypothesis that it is not different genes but conserved biological functions that play a crucial role in the convergence of complex phenotypes. This study provides insight into the genetic basis underlying the EO convergent evolution; however, more studies in different cases will be needed to demonstrate whether this pattern can be extended to other cases to derive a general rule for convergent evolution.
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Affiliation(s)
- Ake Liu
- Faculty of Biology Sciences and Technology, Changzhi University, Changzhi, China.,School of Life Sciences, Fudan University, Shanghai, China
| | - Funan He
- School of Life Sciences, Fudan University, Shanghai, China
| | - Jingqi Zhou
- School of Public Health, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Yangyun Zou
- School of Life Sciences, Fudan University, Shanghai, China
| | - Zhixi Su
- School of Life Sciences, Fudan University, Shanghai, China.,Singlera Genomics Inc., Shanghai, China
| | - Xun Gu
- Department of GDC Biology, Iowa State University, Ames, IA, United States.,Fudan Human Phenome Institute, Shanghai, China
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28
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Tian L, Rahman SR, Ezray BD, Franzini L, Strange JP, Lhomme P, Hines HM. A homeotic shift late in development drives mimetic color variation in a bumble bee. Proc Natl Acad Sci U S A 2019; 116:11857-11865. [PMID: 31043564 PMCID: PMC6575597 DOI: 10.1073/pnas.1900365116] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Natural phenotypic radiations, with their high diversity and convergence, are well-suited for informing how genomic changes translate to natural phenotypic variation. New genomic tools enable discovery in such traditionally nonmodel systems. Here, we characterize the genomic basis of color pattern variation in bumble bees (Hymenoptera, Apidae, Bombus), a group that has undergone extensive convergence of setal color patterns as a result of Müllerian mimicry. In western North America, multiple species converge on local mimicry patterns through parallel shifts of midabdominal segments from red to black. Using genome-wide association, we establish that a cis-regulatory locus between the abdominal fate-determining Hox genes, abd-A and Abd-B, controls the red-black color switch in a western species, Bombus melanopygus Gene expression analysis reveals distinct shifts in Abd-B aligned with the duration of setal pigmentation at the pupal-adult transition. This results in atypical anterior Abd-B expression, a late developmental homeotic shift. Changing expression of Hox genes can have widespread effects, given their important role across segmental phenotypes; however, the late timing reduces this pleiotropy, making Hox genes suitable targets. Analysis of this locus across mimics and relatives reveals that other species follow independent genetic routes to obtain the same phenotypes.
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Affiliation(s)
- Li Tian
- Department of Biology, The Pennsylvania State University, University Park, PA 16802
| | | | - Briana D Ezray
- Department of Entomology, The Pennsylvania State University, University Park, PA 16802
| | - Luca Franzini
- Department of Entomology, The Pennsylvania State University, University Park, PA 16802
| | - James P Strange
- United States Department of Agriculture-Agricultural Research Service Pollinating Insects Research Unit, Utah State University, Logan, UT 84322
| | - Patrick Lhomme
- Department of Biology, The Pennsylvania State University, University Park, PA 16802
- Biodiversity and Crop Improvement Program, International Center of Agricultural Research in the Dry Areas, 10112 Rabat, Morocco
| | - Heather M Hines
- Department of Biology, The Pennsylvania State University, University Park, PA 16802;
- Department of Entomology, The Pennsylvania State University, University Park, PA 16802
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29
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Zhang Y, Li H, Du J, Zhang J, Shen J, Cai W. Three Melanin Pathway Genes, TH, yellow, and aaNAT, Regulate Pigmentation in the Twin-Spotted Assassin Bug, Platymeris biguttatus (Linnaeus). Int J Mol Sci 2019; 20:ijms20112728. [PMID: 31163651 PMCID: PMC6600426 DOI: 10.3390/ijms20112728] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2019] [Revised: 05/25/2019] [Accepted: 05/25/2019] [Indexed: 12/04/2022] Open
Abstract
Pigmentation plays a vital role in insect survival and reproduction. Many melanin pathway genes have been studied in holometabolous insects; however, they have only been studied in two hemimetabolous insect genera, Oncopeltus and Periplaneta. Here we analyzed three melanin pathway genes (TH, yellow, and aaNAT) using RNA interference (RNAi) in another hemimetabolous insect, namely the twin-spotted assassin bug, Platymeris biguttatus. TH was highly expressed in freshly molted nymphs and adults. TH RNAi resulted in a complete loss of black pigment, with yellow coloration maintained. Therefore, black pigment in this assassin bug is solely generated from the melanin pathway, whereas yellow pigment is generated from other unknown pigmentation pathways. yellow and aaNAT were highly expressed in the white spot of the hemelytra. Downregulation of yellow caused a brown phenotype with high mortality, indicating an important role of yellow functions in cuticle formation and in the process of converting melanin from brown to black. Interestingly, aaNAT RNAi caused not only loss of white pigment, but also loss of yellow and red pigments. This phenotype of aaNAT has not been reported in other insects. Our results provide new information for understanding the melanin pathway in which aaNAT is essential for the formation of colorless patterns.
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Affiliation(s)
- Yinqiao Zhang
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, Beijing 100193, China.
| | - Hu Li
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, Beijing 100193, China.
| | - Juan Du
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, Beijing 100193, China.
| | - Junzheng Zhang
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, Beijing 100193, China.
| | - Jie Shen
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, Beijing 100193, China.
| | - Wanzhi Cai
- Department of Entomology and MOA Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, Beijing 100193, China.
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30
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Keesey IW, Grabe V, Gruber L, Koerte S, Obiero GF, Bolton G, Khallaf MA, Kunert G, Lavista-Llanos S, Valenzano DR, Rybak J, Barrett BA, Knaden M, Hansson BS. Inverse resource allocation between vision and olfaction across the genus Drosophila. Nat Commun 2019; 10:1162. [PMID: 30858374 PMCID: PMC6411718 DOI: 10.1038/s41467-019-09087-z] [Citation(s) in RCA: 60] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Accepted: 02/14/2019] [Indexed: 11/09/2022] Open
Abstract
Divergent populations across different environments are exposed to critical sensory information related to locating a host or mate, as well as avoiding predators and pathogens. These sensory signals generate evolutionary changes in neuroanatomy and behavior; however, few studies have investigated patterns of neural architecture that occur between sensory systems, or that occur within large groups of closely-related organisms. Here we examine 62 species within the genus Drosophila and describe an inverse resource allocation between vision and olfaction, which we consistently observe at the periphery, within the brain, as well as during larval development. This sensory variation was noted across the entire genus and appears to represent repeated, independent evolutionary events, where one sensory modality is consistently selected for at the expense of the other. Moreover, we provide evidence of a developmental genetic constraint through the sharing of a single larval structure, the eye-antennal imaginal disc. In addition, we examine the ecological implications of visual or olfactory bias, including the potential impact on host-navigation and courtship.
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Affiliation(s)
- Ian W Keesey
- Max Planck Institute for Chemical Ecology, Department of Evolutionary Neuroethology, Hans-Knöll-Straße 8, D-07745, Jena, Germany
| | - Veit Grabe
- Max Planck Institute for Chemical Ecology, Department of Evolutionary Neuroethology, Hans-Knöll-Straße 8, D-07745, Jena, Germany
| | - Lydia Gruber
- Max Planck Institute for Chemical Ecology, Department of Evolutionary Neuroethology, Hans-Knöll-Straße 8, D-07745, Jena, Germany
| | - Sarah Koerte
- Max Planck Institute for Chemical Ecology, Department of Evolutionary Neuroethology, Hans-Knöll-Straße 8, D-07745, Jena, Germany
| | - George F Obiero
- Max Planck Institute for Chemical Ecology, Department of Evolutionary Neuroethology, Hans-Knöll-Straße 8, D-07745, Jena, Germany
- Department of Biochemistry and Biotechnology, Technical University of Kenya, Haille-Sellasie Avenue, Workshop Road, 0200, Nairobi, Kenya
| | - Grant Bolton
- University of Missouri, Division of Plant Sciences, 3-22I Agriculture Building, Columbia, Missouri, 65211, USA
| | - Mohammed A Khallaf
- Max Planck Institute for Chemical Ecology, Department of Evolutionary Neuroethology, Hans-Knöll-Straße 8, D-07745, Jena, Germany
| | - Grit Kunert
- Max Planck Institute for Chemical Ecology, Department of Biochemistry, Hans-Knöll-Straße 8, D-07745, Jena, Germany
| | - Sofia Lavista-Llanos
- Max Planck Institute for Chemical Ecology, Department of Evolutionary Neuroethology, Hans-Knöll-Straße 8, D-07745, Jena, Germany
| | - Dario Riccardo Valenzano
- Max Planck Institute for Biology of Ageing and CECAD at University of Cologne, Joseph-Stelzmann-Str 9b and 26, Cologne, 50931, Germany
| | - Jürgen Rybak
- Max Planck Institute for Chemical Ecology, Department of Evolutionary Neuroethology, Hans-Knöll-Straße 8, D-07745, Jena, Germany
| | - Bruce A Barrett
- University of Missouri, Division of Plant Sciences, 3-22I Agriculture Building, Columbia, Missouri, 65211, USA
| | - Markus Knaden
- Max Planck Institute for Chemical Ecology, Department of Evolutionary Neuroethology, Hans-Knöll-Straße 8, D-07745, Jena, Germany.
| | - Bill S Hansson
- Max Planck Institute for Chemical Ecology, Department of Evolutionary Neuroethology, Hans-Knöll-Straße 8, D-07745, Jena, Germany.
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31
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Wu CC, Klaesson A, Buskas J, Ranefall P, Mirzazadeh R, Söderberg O, Wolf JBW. In situ quantification of individual mRNA transcripts in melanocytes discloses gene regulation of relevance to speciation. J Exp Biol 2019; 222:jeb194431. [PMID: 30718374 PMCID: PMC6650291 DOI: 10.1242/jeb.194431] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2018] [Accepted: 01/31/2019] [Indexed: 01/12/2023]
Abstract
Functional validation of candidate genes involved in adaptation and speciation remains challenging. Here, we exemplify the utility of a method quantifying individual mRNA transcripts in revealing the molecular basis of divergence in feather pigment synthesis during early-stage speciation in crows. Using a padlock probe assay combined with rolling circle amplification, we quantified cell-type-specific gene expression in the histological context of growing feather follicles. Expression of Tyrosinase Related Protein 1 (TYRP1), Solute Carrier Family 45 member 2 (SLC45A2) and Hematopoietic Prostaglandin D Synthase (HPGDS) was melanocyte-limited and significantly reduced in follicles from hooded crow, explaining the substantially lower eumelanin content in grey versus black feathers. The central upstream Melanocyte Inducing Transcription Factor (MITF) only showed differential expression specific to melanocytes - a feature not captured by bulk RNA-seq. Overall, this study provides insight into the molecular basis of an evolutionary young transition in pigment synthesis, and demonstrates the power of histologically explicit, statistically substantiated single-cell gene expression quantification for functional genetic inference in natural populations.
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Affiliation(s)
- Chi-Chih Wu
- Science of Life Laboratories and Department of Evolutionary Biology, Uppsala University, SE-752 36 Uppsala, Sweden
| | - Axel Klaesson
- Department of Pharmaceutical Biosciences, Uppsala University, SE-752 36 Uppsala, Sweden
| | - Julia Buskas
- Science of Life Laboratories and Department of Evolutionary Biology, Uppsala University, SE-752 36 Uppsala, Sweden
- Department of Physics, Chemistry and Biology (IFM), Linköping University, SE-581 83 Linköping, Sweden
| | - Petter Ranefall
- Science of Life Laboratories and Department of Information Technology, Uppsala University, SE-752 36 Uppsala, Sweden
| | - Reza Mirzazadeh
- Science for Life Laboratory, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm SE-17165, Sweden
| | - Ola Söderberg
- Department of Pharmaceutical Biosciences, Uppsala University, SE-752 36 Uppsala, Sweden
| | - Jochen B W Wolf
- Science of Life Laboratories and Department of Evolutionary Biology, Uppsala University, SE-752 36 Uppsala, Sweden
- Division of Evolutionary Biology, Faculty of Biology, LMU Munich, D-82152 Planegg-Martinsried, Germany
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32
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Rajpurohit S, Schmidt PS. Latitudinal Pigmentation Variation Contradicts Ultraviolet Radiation Exposure: A Case Study in Tropical Indian Drosophila melanogaster. Front Physiol 2019; 10:84. [PMID: 30804808 PMCID: PMC6377395 DOI: 10.3389/fphys.2019.00084] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Accepted: 01/24/2019] [Indexed: 12/04/2022] Open
Abstract
The effects of ultraviolet radiation (UV) on the animal body have been reported in many studies, and melanin has emerged as a protective mechanism. In smaller insects such as Drosophila, replicated patterns of geographical variation in pigmentation have been observed on multiple continents. Such patterns are particularly pronounced on the Indian subcontinent where several species show a parallel cline in pigmentation traits. However, the potential role of UV exposure in generating the observed patterns of pigmentation variation has not been addressed. Here, we examine the association between UV intensity and body pigmentation in D. melanogaster natural populations collected along the latitudinal gradient of the Indian subcontinent. A strong negative relationship was observed between UV intensity and body pigmentation. This analysis clearly indicates that, in the sampled populations, pigmentation variation is independent of UV exposure and related selection pressures. Patterns of pigmentation in natural populations from the Indian subcontinent are better predicted by latitude itself and temperature-related climatic variables.
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Affiliation(s)
- Subhash Rajpurohit
- Division of Biological and Life Sciences, School of Arts and Sciences, Ahmedabad University, Ahmedabad, India
| | - Paul S Schmidt
- Department of Biology, University of Pennsylvania, Philadelphia, PA, United States
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33
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Guo Z, Qin J, Zhou X, Zhang Y. Insect Transcription Factors: A Landscape of Their Structures and Biological Functions in Drosophila and beyond. Int J Mol Sci 2018; 19:ijms19113691. [PMID: 30469390 PMCID: PMC6274879 DOI: 10.3390/ijms19113691] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Revised: 11/16/2018] [Accepted: 11/16/2018] [Indexed: 12/17/2022] Open
Abstract
Transcription factors (TFs) play essential roles in the transcriptional regulation of functional genes, and are involved in diverse physiological processes in living organisms. The fruit fly Drosophila melanogaster, a simple and easily manipulated organismal model, has been extensively applied to study the biological functions of TFs and their related transcriptional regulation mechanisms. It is noteworthy that with the development of genetic tools such as CRISPR/Cas9 and the next-generation genome sequencing techniques in recent years, identification and dissection the complex genetic regulatory networks of TFs have also made great progress in other insects beyond Drosophila. However, unfortunately, there is no comprehensive review that systematically summarizes the structures and biological functions of TFs in both model and non-model insects. Here, we spend extensive effort in collecting vast related studies, and attempt to provide an impartial overview of the progress of the structure and biological functions of current documented TFs in insects, as well as the classical and emerging research methods for studying their regulatory functions. Consequently, considering the importance of versatile TFs in orchestrating diverse insect physiological processes, this review will assist a growing number of entomologists to interrogate this understudied field, and to propel the progress of their contributions to pest control and even human health.
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Affiliation(s)
- Zhaojiang Guo
- Department of Plant Protection, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
| | - Jianying Qin
- Department of Plant Protection, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
- Longping Branch, Graduate School of Hunan University, Changsha 410125, China.
| | - Xiaomao Zhou
- Longping Branch, Graduate School of Hunan University, Changsha 410125, China.
| | - Youjun Zhang
- Department of Plant Protection, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
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Iwanishi S, Zaitsu S, Shibata H, Nitasaka E. An albino mutant of the Japanese rat snake (Elaphe climacophora) carries a nonsense mutation in the tyrosinase gene. Genes Genet Syst 2018; 93:163-167. [PMID: 30158334 DOI: 10.1266/ggs.18-00021] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
The Japanese rat snake (Elaphe climacophora) is a common species in Japan and is widely distributed across the Japanese islands. An albino mutant of the Japanese rat snake ("pet trade" albino) has been bred and traded by hobbyists for around two decades because of its remarkable light-yellowish coloration with red eyes, attributable to a lack of melanin. Another albino Japanese rat snake mutant found in a natural population of the Japanese rat snake at high frequency in Iwakuni City, Yamaguchi Prefecture is known as "Iwakuni no Shirohebi". It has been conserved by the government as a natural monument. The Iwakuni albino also lacks melanin, having light-yellowish body coloration and red eyes. Albino mutants of several organisms have been studied, and mutation of the tyrosinase gene (TYR) is responsible for this phenotype. By determining the sequence of the TYR coding region of the pet trade albino, we identified a nonsense mutation in the second exon. Furthermore, RT-PCR revealed that TYR transcripts were not detected in this snake. These findings suggest that mutation of TYR is responsible for the albino phenotype of the pet trade line of the Japanese rat snake. However, the Iwakuni albino did not share this TYR mutation; thus, these two albino lines differ in their origins.
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Affiliation(s)
- Shuzo Iwanishi
- Graduate School of Systems Life Sciences, Kyushu University
| | - Shohei Zaitsu
- Graduate School of Systems Life Sciences, Kyushu University
| | - Hiroki Shibata
- Division of Genomics, Medical Institute of Bioregulation, Kyushu University
| | - Eiji Nitasaka
- Department of Biological Science, Faculty of Science, Kyushu University
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35
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Panettieri S, Gjinaj E, John G, Lohman DJ. Different ommochrome pigment mixtures enable sexually dimorphic Batesian mimicry in disjunct populations of the common palmfly butterfly, Elymnias hypermnestra. PLoS One 2018; 13:e0202465. [PMID: 30208047 PMCID: PMC6135364 DOI: 10.1371/journal.pone.0202465] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Accepted: 08/04/2018] [Indexed: 11/18/2022] Open
Abstract
With varied, brightly patterned wings, butterflies have been the focus of much work on the evolution and development of phenotypic novelty. However, the chemical structures of wing pigments from few butterfly species have been identified. We characterized the orange wing pigments of female Elymnias hypermnestra butterflies (Lepidoptera: Nymphalidae: Satyrinae) from two Southeast Asian populations. This species is a sexually dimorphic Batesian mimic of several model species. Females are polymorphic: in some populations, females are dark, resemble conspecific males, and mimic Euploea spp. In other populations, females differ from males and mimic orange Danaus spp. Using LC-MS/MS, we identified nine ommochrome pigments: six from a population in Chiang Mai, Thailand, and five compounds from a population in Bali, Indonesia. Two ommochromes were found in both populations, and only two of the nine compounds have been previously reported. The sexually dimorphic Thai and Balinese populations are separated spatially by monomorphic populations in peninsular Malaysia, Singapore, and Sumatra, suggesting independent evolution of mimetic female wing pigments in these disjunct populations. These results indicate that other butterfly wing pigments remain to be discovered.
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Affiliation(s)
- Silvio Panettieri
- Department of Chemistry and Biochemistry, City College of New York, City University of New York, New York, NY, United States of America
- Ph.D. Program in Chemistry, Graduate Center, City University of New York, New York, NY, United States of America
| | - Erisa Gjinaj
- Department of Chemistry and Biochemistry, City College of New York, City University of New York, New York, NY, United States of America
| | - George John
- Department of Chemistry and Biochemistry, City College of New York, City University of New York, New York, NY, United States of America
- Ph.D. Program in Chemistry, Graduate Center, City University of New York, New York, NY, United States of America
- * E-mail: (DJL); (GJ)
| | - David J. Lohman
- Biology Department, City College of New York, City University of New York, New York, NY, United States of America
- Ph.D. Program in Biology, Graduate Center, City University of New York, New York, NY, United States of America
- Entomology Section, National Museum of the Philippines, Manila, Philippines
- * E-mail: (DJL); (GJ)
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36
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Endler L, Gibert J, Nolte V, Schlötterer C. Pleiotropic effects of regulatory variation in tan result in correlation of two pigmentation traits in Drosophila melanogaster. Mol Ecol 2018; 27:3207-3218. [PMID: 29957826 PMCID: PMC6120501 DOI: 10.1111/mec.14781] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Revised: 05/24/2018] [Accepted: 06/25/2018] [Indexed: 01/10/2023]
Abstract
Traits with a common genetic basis frequently display correlated phenotypic responses to selection or environmental conditions. In Drosophila melanogaster, pigmentation of the abdomen and a trident-shaped region on the thorax are genetically correlated. Here, we used a pooled replicated genomewide association approach (Pool-GWAS) to identify the genetic basis of variation in thoracic trident pigmentation in two Drosophila melanogaster populations. We confirmed the previously reported large effect of ebony and the association of the cosmopolitan inversion In(3R)Payne. For the first time, we identified tan as another major locus contributing to variation in trident pigmentation. Intriguingly, the regulatory variants of tan that were most strongly associated with female abdominal pigmentation also showed a strong association with trident pigmentation. We validated this common genetic basis in transgenic assays and found qualitatively similar effects on trident and abdominal pigmentation. Further work is required to determine whether this genetic correlation is favoured by natural selection or reflects a neutral by-product of a shared regulatory architecture.
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Affiliation(s)
- Lukas Endler
- Institute of PopulationsgenetikVetmeduni WienWienAustria
| | - Jean‐Michel Gibert
- CNRSBiologie du Développement Paris Seine‐Institut de Biologie Paris Seine (LBD‐IBPS)Sorbonne UniversitéParisFrance
| | - Viola Nolte
- Institute of PopulationsgenetikVetmeduni WienWienAustria
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Re C, Fišer Ž, Perez J, Tacdol A, Trontelj P, Protas ME. Common Genetic Basis of Eye and Pigment Loss in Two Distinct Cave Populations of the Isopod Crustacean Asellus aquaticus. Integr Comp Biol 2018; 58:421-430. [DOI: 10.1093/icb/icy028] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Cassandra Re
- Dominican University of California, 50 Acacia Avenue, San Rafael, CA 94901, USA
| | - Žiga Fišer
- Department of Biology, Biotechnical Faculty, University of Ljubljana, Ljubljana SI-1000, Slovenia
| | - Justin Perez
- Dominican University of California, 50 Acacia Avenue, San Rafael, CA 94901, USA
| | - Allyson Tacdol
- Dominican University of California, 50 Acacia Avenue, San Rafael, CA 94901, USA
| | - Peter Trontelj
- Department of Biology, Biotechnical Faculty, University of Ljubljana, Ljubljana SI-1000, Slovenia
| | - Meredith E Protas
- Dominican University of California, 50 Acacia Avenue, San Rafael, CA 94901, USA
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Hinaux H, Bachem K, Battistara M, Rossi M, Xin Y, Jaenichen R, Le Poul Y, Arnoult L, Kobler JM, Grunwald Kadow IC, Rodermund L, Prud'homme B, Gompel N. Revisiting the developmental and cellular role of the pigmentation gene yellow in Drosophila using a tagged allele. Dev Biol 2018; 438:111-123. [PMID: 29634916 DOI: 10.1016/j.ydbio.2018.04.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Revised: 03/28/2018] [Accepted: 04/06/2018] [Indexed: 10/17/2022]
Abstract
Pigmentation is a diverse and ecologically relevant trait in insects. Pigment formation has been studied extensively at the genetic and biochemical levels. The temporality of pigment formation during animal development, however, is more elusive. Here, we examine this temporality, focusing on yellow, a gene involved in the formation of black melanin. We generated a protein-tagged yellow allele in the fruit fly Drosophila melanogaster, which allowed us to precisely describe Yellow expression pattern at the tissue and cellular levels throughout development. We found Yellow expressed in the pupal epidermis in patterns prefiguring black pigmentation. We also found Yellow expressed in a few central neurons from the second larval instar to adult stages, including a subset of neurons adjacent to the clock neurons marked by the gene Pdf. We then specifically examined the dynamics of Yellow expression domain and subcellular localization in relationship to pigment formation. In particular, we showed how a late step of re-internalization is regulated by the large low-density lipoprotein receptor-related protein Megalin. Finally we suggest a new function for Yellow in the establishment of sharp pigmentation pattern boundaries, whereby this protein may assume a structural role, anchoring pigment deposits or pigmentation enzymes in the cuticle.
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Affiliation(s)
- Hélène Hinaux
- Ludwig-Maximilians Universität München, Fakultät für Biologie, Biozentrum, Grosshaderner Strasse 2, 82152 Planegg-Martinsried, Germany
| | - Katharina Bachem
- Ludwig-Maximilians Universität München, Fakultät für Biologie, Biozentrum, Grosshaderner Strasse 2, 82152 Planegg-Martinsried, Germany
| | - Margherita Battistara
- Ludwig-Maximilians Universität München, Fakultät für Biologie, Biozentrum, Grosshaderner Strasse 2, 82152 Planegg-Martinsried, Germany
| | - Matteo Rossi
- Ludwig-Maximilians Universität München, Fakultät für Biologie, Biozentrum, Grosshaderner Strasse 2, 82152 Planegg-Martinsried, Germany
| | - Yaqun Xin
- Ludwig-Maximilians Universität München, Fakultät für Biologie, Biozentrum, Grosshaderner Strasse 2, 82152 Planegg-Martinsried, Germany
| | - Rita Jaenichen
- Ludwig-Maximilians Universität München, Fakultät für Biologie, Biozentrum, Grosshaderner Strasse 2, 82152 Planegg-Martinsried, Germany
| | - Yann Le Poul
- Ludwig-Maximilians Universität München, Fakultät für Biologie, Biozentrum, Grosshaderner Strasse 2, 82152 Planegg-Martinsried, Germany
| | - Laurent Arnoult
- Aix-Marseille Université, CNRS, IBDM, Institut de Biologie du Développement de Marseille, Campus de Luminy Case 907, 13288 Marseille Cedex 9, France
| | - Johanna M Kobler
- Technical University of Munich, School of Life Sciences, ZIEL - Institute for Food And Health, Liesel-Beckmann-Str. 4, 85354 Freising, Germany; Chemosensory Coding, Max-Planck Institute of Neurobiology, Am Klopferspitz 18, 82152 Planegg-Martinsried, Germany
| | - Ilona C Grunwald Kadow
- Technical University of Munich, School of Life Sciences, ZIEL - Institute for Food And Health, Liesel-Beckmann-Str. 4, 85354 Freising, Germany
| | - Lisa Rodermund
- Ludwig-Maximilians Universität München, Fakultät für Biologie, Biozentrum, Grosshaderner Strasse 2, 82152 Planegg-Martinsried, Germany
| | - Benjamin Prud'homme
- Aix-Marseille Université, CNRS, IBDM, Institut de Biologie du Développement de Marseille, Campus de Luminy Case 907, 13288 Marseille Cedex 9, France
| | - Nicolas Gompel
- Ludwig-Maximilians Universität München, Fakultät für Biologie, Biozentrum, Grosshaderner Strasse 2, 82152 Planegg-Martinsried, Germany.
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McGirr JA, Martin CH. Parallel evolution of gene expression between trophic specialists despite divergent genotypes and morphologies. Evol Lett 2018; 2:62-75. [PMID: 30283665 PMCID: PMC6089502 DOI: 10.1002/evl3.41] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2017] [Revised: 12/22/2017] [Accepted: 01/03/2018] [Indexed: 12/20/2022] Open
Abstract
Parallel evolution of gene expression commonly underlies convergent niche specialization, but parallel changes in expression could also underlie divergent specialization. We investigated divergence in gene expression and whole-genome genetic variation across three sympatric Cyprinodon pupfishes endemic to San Salvador Island, Bahamas. This recent radiation consists of a generalist and two derived specialists adapted to novel niches: a scale-eating and a snail-eating pupfish. We sampled total mRNA from all three species at two early developmental stages and compared gene expression with whole-genome genetic differentiation among all three species in 42 resequenced genomes. Eighty percent of genes that were differentially expressed between snail-eaters and generalists were up or down regulated in the same direction between scale-eaters and generalists; however, there were no fixed variants shared between species underlying these parallel changes in expression. Genes showing parallel evolution of expression were enriched for effects on metabolic processes, whereas genes showing divergent expression were enriched for effects on cranial skeleton development and pigment biosynthesis, reflecting the most divergent phenotypes observed between specialist species. Our findings reveal that even divergent niche specialists may exhibit convergent adaptation to higher trophic levels through shared genetic pathways. This counterintuitive result suggests that parallel evolution in gene expression can accompany divergent ecological speciation during adaptive radiation.
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Affiliation(s)
- Joseph A. McGirr
- Department of BiologyUniversity of North Carolina at Chapel HillChapel HillNorth Carolina27514
| | - Christopher H. Martin
- Department of BiologyUniversity of North Carolina at Chapel HillChapel HillNorth Carolina27514
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40
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San-Jose LM, Roulin A. Genomics of coloration in natural animal populations. Philos Trans R Soc Lond B Biol Sci 2018; 372:rstb.2016.0337. [PMID: 28533454 DOI: 10.1098/rstb.2016.0337] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/15/2017] [Indexed: 12/28/2022] Open
Abstract
Animal coloration has traditionally been the target of genetic and evolutionary studies. However, until very recently, the study of the genetic basis of animal coloration has been mainly restricted to model species, whereas research on non-model species has been either neglected or mainly based on candidate approaches, and thereby limited by the knowledge obtained in model species. Recent high-throughput sequencing technologies allow us to overcome previous limitations, and open new avenues to study the genetic basis of animal coloration in a broader number of species and colour traits, and to address the general relevance of different genetic structures and their implications for the evolution of colour. In this review, we highlight aspects where genome-wide studies could be of major utility to fill in the gaps in our understanding of the biology and evolution of animal coloration. The new genomic approaches have been promptly adopted to study animal coloration although substantial work is still needed to consider a larger range of species and colour traits, such as those exhibiting continuous variation or based on reflective structures. We argue that a robust advancement in the study of animal coloration will also require large efforts to validate the functional role of the genes and variants discovered using genome-wide tools.This article is part of the themed issue 'Animal coloration: production, perception, function and application'.
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Affiliation(s)
- Luis M San-Jose
- Department of Ecology and Evolution, University of Lausanne, Building Le Biophore, 1015 Lausanne, Switzerland
| | - Alexandre Roulin
- Department of Ecology and Evolution, University of Lausanne, Building Le Biophore, 1015 Lausanne, Switzerland
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41
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Genetic Basis of Body Color and Spotting Pattern in Redheaded Pine Sawfly Larvae ( Neodiprion lecontei). Genetics 2018; 209:291-305. [PMID: 29496749 DOI: 10.1534/genetics.118.300793] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2017] [Accepted: 02/22/2018] [Indexed: 11/18/2022] Open
Abstract
Pigmentation has emerged as a premier model for understanding the genetic basis of phenotypic evolution, and a growing catalog of color loci is starting to reveal biases in the mutations, genes, and genetic architectures underlying color variation in the wild. However, existing studies have sampled a limited subset of taxa, color traits, and developmental stages. To expand the existing sample of color loci, we performed QTL mapping analyses on two types of larval pigmentation traits that vary among populations of the redheaded pine sawfly (Neodiprion lecontei): carotenoid-based yellow body color and melanin-based spotting pattern. For both traits, our QTL models explained a substantial proportion of phenotypic variation and suggested a genetic architecture that is neither monogenic nor highly polygenic. Additionally, we used our linkage map to anchor the current N. lecontei genome assembly. With these data, we identified promising candidate genes underlying (1) a loss of yellow pigmentation in populations in the mid-Atlantic/northeastern United States [C locus-associated membrane protein homologous to a mammalian HDL receptor-2 gene (Cameo2) and lipid transfer particle apolipoproteins II and I gene (apoLTP-II/I)], and (2) a pronounced reduction in black spotting in Great Lakes populations [members of the yellow gene family, tyrosine hydroxylase gene (pale), and dopamine N-acetyltransferase gene (Dat)]. Several of these genes also contribute to color variation in other wild and domesticated taxa. Overall, our findings are consistent with the hypothesis that predictable genes of large effect contribute to color evolution in nature.
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42
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Feng D, Li Q, Yu H, Kong L, Du S. Transcriptional profiling of long non-coding RNAs in mantle of Crassostrea gigas and their association with shell pigmentation. Sci Rep 2018; 8:1436. [PMID: 29362405 PMCID: PMC5780484 DOI: 10.1038/s41598-018-19950-6] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2017] [Accepted: 01/10/2018] [Indexed: 02/07/2023] Open
Abstract
Long non-coding RNAs (lncRNAs) play crucial roles in diverse biological processes and have drawn extensive attention in the past few years. However, lncRNAs remain poorly understood about expression and roles in Crassostrea gigas, a potential model organism for marine molluscan studies. Here, we systematically identified lncRNAs in the mantles of C. gigas from four full-sib families characterized by white, black, golden, and partially pigmented shell. Using poly(A)-independent and strand-specific RNA-seq, a total of 441,205,852 clean reads and 12,243 lncRNA transcripts were obtained. LncRNA transcripts were relatively short with few exons and low levels of expression in comparison to protein coding mRNA transcripts. A total of 427 lncRNAs and 349 mRNAs were identified to differentially express among six pairwise groups, mainly involving in biomineralization and pigmentation through functional enrichment. Furthermore, a total of 6 mRNAs and their cis-acting lncRNAs were predicted to involve in synthesis of melanin, carotenoid, tetrapyrrole, or ommochrome. Of them, chorion peroxidase and its cis-acting lincRNA TCONS_00951105 are implicated in playing an essential role in the melanin synthetic pathway. Our studies provided the first systematic characterization of lncRNAs catalog expressed in oyster mantle, which may facilitate understanding the molecular regulation of shell colour diversity and provide new insights into future selective breeding of C. gigas for aquaculture.
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Affiliation(s)
- Dandan Feng
- Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, Qingdao, 266003, China
| | - Qi Li
- Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, Qingdao, 266003, China.
- Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266237, China.
| | - Hong Yu
- Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, Qingdao, 266003, China
| | - Lingfeng Kong
- Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, Qingdao, 266003, China
| | - Shaojun Du
- Institute of Marine and Environmental Technology, Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD, United States
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43
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Feindt W, Oppenheim SJ, DeSalle R, Goldstein PZ, Hadrys H. Transcriptome profiling with focus on potential key genes for wing development and evolution in Megaloprepus caerulatus, the damselfly species with the world's largest wings. PLoS One 2018; 13:e0189898. [PMID: 29329292 PMCID: PMC5766104 DOI: 10.1371/journal.pone.0189898] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2017] [Accepted: 12/04/2017] [Indexed: 11/20/2022] Open
Abstract
The evolution, development and coloration of insect wings remains a puzzling subject in evolutionary research. In basal flying insects such as Odonata, genomic research regarding bauplan evolution is still rare. Here we focus on the world's largest odonate species-the "forest giant" Megaloprepus caerulatus, to explore its potential for looking deeper into the development and evolution of wings. A recently discovered cryptic species complex in this genus previously considered monotypic is characterized by morphological differences in wing shape and color patterns. As a first step toward understanding wing pattern divergence and pathways involved in adaptation and speciation at the genomic level, we present a transcriptome profiling of M. caerulatus using RNA-Seq and compare these data with two other odonate species. The de novo transcriptome assembly consists of 61,560 high quality transcripts and is approximately 93% complete. For almost 75% of the identified transcripts a possible function could be assigned: 48,104 transcripts had a hit to an InterPro protein family or domain, and 28,653 were mapped to a Gene Ontology term. In particular, we focused on genes related to wing development and coloration. The comparison with two other species revealed larva-specific genes and a conserved 'core' set of over 8,000 genes forming orthologous clusters with Ischnura elegans and Ladona fulva. This transcriptome may provide a first point of reference for future research in odonates addressing questions surrounding the evolution of wing development, wing coloration and their role in speciation.
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Affiliation(s)
- Wiebke Feindt
- University of Veterinary Medicine Hannover, ITZ—Division of Ecology and Evolution, Hannover, Germany
- Leibniz University Hannover, Hannover, Germany
| | - Sara J. Oppenheim
- American Museum of Natural History, Sackler Institute for Comparative Genomics, New York, NY, United States of America
| | - Robert DeSalle
- American Museum of Natural History, Sackler Institute for Comparative Genomics, New York, NY, United States of America
| | - Paul Z. Goldstein
- Systematic Entomology Laboratory (USDA-ARS), National Museum of Natural History, Washington, DC, United States of America
| | - Heike Hadrys
- University of Veterinary Medicine Hannover, ITZ—Division of Ecology and Evolution, Hannover, Germany
- American Museum of Natural History, Sackler Institute for Comparative Genomics, New York, NY, United States of America
- Yale University, Department of Ecology & Evolutionary Biology, New Haven, Connecticut, United States of America
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44
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San-Jose LM, Ducret V, Ducrest AL, Simon C, Roulin A. Beyond mean allelic effects: A locus at the major color gene MC1R associates also with differing levels of phenotypic and genetic (co)variance for coloration in barn owls. Evolution 2017; 71:2469-2483. [PMID: 28861897 DOI: 10.1111/evo.13343] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Revised: 08/09/2017] [Accepted: 08/11/2017] [Indexed: 01/05/2023]
Abstract
The mean phenotypic effects of a discovered variant help to predict major aspects of the evolution and inheritance of a phenotype. However, differences in the phenotypic variance associated to distinct genotypes are often overlooked despite being suggestive of processes that largely influence phenotypic evolution, such as interactions between the genotypes with the environment or the genetic background. We present empirical evidence for a mutation at the melanocortin-1-receptor gene, a major vertebrate coloration gene, affecting phenotypic variance in the barn owl, Tyto alba. The white MC1R allele, which associates with whiter plumage coloration, also associates with a pronounced phenotypic and additive genetic variance for distinct color traits. Contrarily, the rufous allele, associated with a rufous coloration, relates to a lower phenotypic and additive genetic variance, suggesting that this allele may be epistatic over other color loci. Variance differences between genotypes entailed differences in the strength of phenotypic and genetic associations between color traits, suggesting that differences in variance also alter the level of integration between traits. This study highlights that addressing variance differences of genotypes in wild populations provides interesting new insights into the evolutionary mechanisms and the genetic architecture underlying the phenotype.
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Affiliation(s)
- Luis M San-Jose
- Department of Ecology and Evolution, University of Lausanne, Biophore Building, CH-1015 Lausanne, Switzerland
| | - Valérie Ducret
- Department of Ecology and Evolution, University of Lausanne, Biophore Building, CH-1015 Lausanne, Switzerland
| | - Anne-Lyse Ducrest
- Department of Ecology and Evolution, University of Lausanne, Biophore Building, CH-1015 Lausanne, Switzerland
| | - Céline Simon
- Department of Ecology and Evolution, University of Lausanne, Biophore Building, CH-1015 Lausanne, Switzerland
| | - Alexandre Roulin
- Department of Ecology and Evolution, University of Lausanne, Biophore Building, CH-1015 Lausanne, Switzerland
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45
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Whitten MMA, Coates CJ. Re-evaluation of insect melanogenesis research: Views from the dark side. Pigment Cell Melanoma Res 2017; 30:386-401. [PMID: 28378380 DOI: 10.1111/pcmr.12590] [Citation(s) in RCA: 66] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Accepted: 03/29/2017] [Indexed: 12/16/2022]
Abstract
Melanins (eumelanin and pheomelanin) are synthesized in insects for several purposes including cuticle sclerotization and color patterning, clot formation, organogenesis, and innate immunity. Traditional views of insect immunity detail the storage of pro-phenoloxidases inside specialized blood cells (hemocytes) and their release upon recognition of foreign bodies. Activated phenoloxidases convert monophenols into reactive quinones in a two-step enzymatic reaction, and until recently, the mechanism of tyrosine hydroxylation remained a mystery. Herein, we present our interpretations of these enzyme-substrate complexes. The resultant melanins are deposited onto the surface of microbes to immobilize, agglutinate, and suffocate them. Phenoloxidase activity and melanin production are not limited to the blood (hemolymph) or cuticle, as recent evidence points to more diverse, sophisticated interactions in the gut and with the resident symbionts. This review offers insight into the somewhat neglected areas of insect melanogenesis research, particularly in innate immunity, its role in beneficial insects such as pollinators, the functional versatility of phenoloxidases, and the limitations of common experimental approaches that may impede progress inadvertently.
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46
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Saleh Ziabari O, Shingleton AW. Quantifying Abdominal Pigmentation in Drosophila melanogaster. J Vis Exp 2017. [PMID: 28605370 DOI: 10.3791/55732] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Pigmentation is a morphologically simple but highly variable trait that often has adaptive significance. It has served extensively as a model for understanding the development and evolution of morphological phenotypes. Abdominal pigmentation in Drosophila melanogaster has been particularly useful, allowing researchers to identify the loci that underlie inter- and intraspecific variations in morphology. Hitherto, however, D. melanogaster abdominal pigmentation has been largely assayed qualitatively, through scoring, rather than quantitatively, which limits the forms of statistical analysis that can be applied to pigmentation data. This work describes a new methodology that allows for the quantification of various aspects of the abdominal pigmentation pattern of adult D. melanogaster. The protocol includes specimen mounting, image capture, data extraction, and analysis. All the software used for image capture and analysis feature macros written for open-source image analysis. The advantage of this approach is the ability to precisely measure pigmentation traits using a methodology that is highly reproducible across different imaging systems. While the technique has been used to measure variation in the tergal pigmentation patterns of adult D. melanogaster, the methodology is flexible and broadly applicable to pigmentation patterns in myriad different organisms.
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47
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Manukyan L, Montandon SA, Fofonjka A, Smirnov S, Milinkovitch MC. A living mesoscopic cellular automaton made of skin scales. Nature 2017; 544:173-179. [DOI: 10.1038/nature22031] [Citation(s) in RCA: 80] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2016] [Accepted: 03/01/2017] [Indexed: 11/09/2022]
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48
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Pimsler ML, Jackson JM, Lozier JD. Population genomics reveals a candidate gene involved in bumble bee pigmentation. Ecol Evol 2017; 7:3406-3413. [PMID: 28515876 PMCID: PMC5433978 DOI: 10.1002/ece3.2935] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2016] [Revised: 02/27/2017] [Accepted: 03/03/2017] [Indexed: 01/03/2023] Open
Abstract
Variation in bumble bee color patterns is well‐documented within and between species. Identifying the genetic mechanisms underlying such variation may be useful in revealing evolutionary forces shaping rapid phenotypic diversification. The widespread North American species Bombus bifarius exhibits regional variation in abdominal color forms, ranging from red‐banded to black‐banded phenotypes and including geographically and phenotypically intermediate forms. Identifying genomic regions linked to this variation has been complicated by strong, near species level, genome‐wide differentiation between red‐ and black‐banded forms. Here, we instead focus on the closely related black‐banded and intermediate forms that both belong to the subspecies B. bifarius nearcticus. We analyze an RNA sequencing (RNAseq) data set and identify a cluster of single nucleotide polymorphisms (SNPs) within one gene, Xanthine dehydrogenase/oxidase‐like, that exhibit highly unusual differentiation compared to the rest of the sequenced genome. Homologs of this gene contribute to pigmentation in other insects, and results thus represent a strong candidate for investigating the genetic basis of pigment variation in B. bifarius and other bumble bee mimicry complexes.
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Affiliation(s)
- Meaghan L Pimsler
- Department of Biological Sciences University of Alabama Tuscaloosa AL USA
| | - Jason M Jackson
- Department of Biological Sciences University of Alabama Tuscaloosa AL USA
| | - Jeffrey D Lozier
- Department of Biological Sciences University of Alabama Tuscaloosa AL USA
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49
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Fukutomi Y, Matsumoto K, Agata K, Funayama N, Koshikawa S. Pupal development and pigmentation process of a polka-dotted fruit fly, Drosophila guttifera (Insecta, Diptera). Dev Genes Evol 2017; 227:171-180. [PMID: 28280924 DOI: 10.1007/s00427-017-0578-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2016] [Accepted: 02/21/2017] [Indexed: 12/21/2022]
Abstract
Various organisms have color patterns on their body surfaces, and these color patterns are thought to contribute to physiological regulation, communication with conspecifics, and signaling with the environment. An adult fly of Drosophila guttifera (Insecta: Diptera: Drosophilidae) has melanin pigmentation patterns on its body and wings. Though D. guttifera has been used for research into color pattern formation, how its pupal development proceeds and when the pigmentation starts have not been well studied. In this study, we defined the pupal stages of D. guttifera and measured the pigment content of wing spots from the pupal period to the period after eclosion. Using a transgenic line which carries eGFP connected with an enhancer of yellow, a gene necessary for melanin synthesis, we analyzed the timing at which the yellow enhancer starts to drive eGFP. We also analyzed the distribution of Yellow-producing cells, as indicated by the expression of eGFP during pupal and young adult periods. The results suggested that Yellow-producing cells were removed from wings within 3 h after eclosion, and wing pigmentation continued without epithelial cells. Furthermore, the results of vein cutting experiments showed that the transport of melanin precursors through veins was necessary for wing pigmentation. These results showed the importance of melanin precursors transported through veins and of extracellular factors which were secreted from epithelial cells and left in the cuticle.
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Affiliation(s)
- Yuichi Fukutomi
- Graduate School of Science, Kyoto University, Kitashirakawa-Oiwake-Cho, Sakyo-ku, Kyoto, 606-8502, Japan
| | - Keiji Matsumoto
- Graduate School of Science, Kyoto University, Kitashirakawa-Oiwake-Cho, Sakyo-ku, Kyoto, 606-8502, Japan
| | - Kiyokazu Agata
- Graduate School of Science, Kyoto University, Kitashirakawa-Oiwake-Cho, Sakyo-ku, Kyoto, 606-8502, Japan.,Graduate School of Science, Gakushuin University, Mejiro 1-5-1, Toshima-ku, Tokyo, 171-8588, Japan
| | - Noriko Funayama
- Graduate School of Science, Kyoto University, Kitashirakawa-Oiwake-Cho, Sakyo-ku, Kyoto, 606-8502, Japan
| | - Shigeyuki Koshikawa
- Graduate School of Science, Kyoto University, Kitashirakawa-Oiwake-Cho, Sakyo-ku, Kyoto, 606-8502, Japan. .,The Hakubi Center for Advanced Research, Kyoto University, Yoshida-Honmachi, Sakyo-ku, Kyoto, 606-8501, Japan.
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50
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Eroh GD, Clayton FC, Florell SR, Cassidy PB, Chirife A, Marón CF, Valenzuela LO, Campbell MS, Seger J, Rowntree VJ, Leachman SA. Cellular and ultrastructural characterization of the grey-morph phenotype in southern right whales (Eubalaena australis). PLoS One 2017; 12:e0171449. [PMID: 28170433 PMCID: PMC5295704 DOI: 10.1371/journal.pone.0171449] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Accepted: 01/20/2017] [Indexed: 11/18/2022] Open
Abstract
Southern right whales (SRWs, Eubalena australis) are polymorphic for an X-linked pigmentation pattern known as grey morphism. Most SRWs have completely black skin with white patches on their bellies and occasionally on their backs; these patches remain white as the whale ages. Grey morphs (previously referred to as partial albinos) appear mostly white at birth, with a splattering of rounded black marks; but as the whales age, the white skin gradually changes to a brownish grey color. The cellular and developmental bases of grey morphism are not understood. Here we describe cellular and ultrastructural features of grey-morph skin in relation to that of normal, wild-type skin. Melanocytes were identified histologically and counted, and melanosomes were measured using transmission electron microscopy. Grey-morph skin had fewer melanocytes when compared to wild-type skin, suggesting reduced melanocyte survival, migration, or proliferation in these whales. Grey-morph melanocytes had smaller melanosomes relative to wild-type skin, normal transport of melanosomes to surrounding keratinocytes, and normal localization of melanin granules above the keratinocyte nuclei. These findings indicate that SRW grey-morph pigmentation patterns are caused by reduced numbers of melanocytes in the skin, as well as by reduced amounts of melanin production and/or reduced sizes of mature melanosomes. Grey morphism is distinct from piebaldism and albinism found in other species, which are genetic pigmentation conditions resulting from the local absence of melanocytes, or the inability to synthesize melanin, respectively.
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Affiliation(s)
- Guy D. Eroh
- Huntsman Cancer Institute, Salt Lake City, Utah, United States of America
- University of Georgia, Athens, Georgia, United States of America
| | - Fred C. Clayton
- Department of Pathology, University of Utah, Salt Lake City, Utah, United States of America
| | - Scott R. Florell
- Department of Dermatology, University of Utah, Salt Lake City, Utah, United States of America
| | - Pamela B. Cassidy
- Huntsman Cancer Institute, Salt Lake City, Utah, United States of America
- Department of Dermatology, Oregon Health & Science University, Portland, Oregon, United States of America
| | - Andrea Chirife
- Programa de Monitoreo Sanitario Ballena Franca Austral, Puerto Madryn, Chubut, Argentina
| | - Carina F. Marón
- Department of Biology, University of Utah, Salt Lake City, Utah, United States of America
- Instituto de Conservación de Ballenas, Buenos Aires, Argentina
| | - Luciano O. Valenzuela
- Department of Biology, University of Utah, Salt Lake City, Utah, United States of America
- Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Ciencias Sociales, Universidad Nacional del Centro de la Provincia de Buenos Aires, Buenos Aires, Argentina
| | - Michael S. Campbell
- Department of Pediatrics, University of Utah, Salt Lake City, Utah, United States of America
- Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, United States of America
| | - Jon Seger
- Department of Biology, University of Utah, Salt Lake City, Utah, United States of America
| | - Victoria J. Rowntree
- Programa de Monitoreo Sanitario Ballena Franca Austral, Puerto Madryn, Chubut, Argentina
- Department of Biology, University of Utah, Salt Lake City, Utah, United States of America
- Instituto de Conservación de Ballenas, Buenos Aires, Argentina
- Ocean Alliance/Whale Conservation Institute, Gloucester, Massachusetts, United States of America
| | - Sancy A. Leachman
- Huntsman Cancer Institute, Salt Lake City, Utah, United States of America
- Department of Dermatology, Oregon Health & Science University, Portland, Oregon, United States of America
- * E-mail:
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