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1.
Nat Commun ; 12(1): 50, 2021 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-33397914

RESUMO

Gene flow is predicted to impede parallel adaptation via de novo mutation, because it can introduce pre-existing adaptive alleles from population to population. We test this using Hawaiian crickets (Teleogryllus oceanicus) in which 'flatwing' males that lack sound-producing wing structures recently arose and spread under selection from an acoustically-orienting parasitoid. Morphometric and genetic comparisons identify distinct flatwing phenotypes in populations on three islands, localized to different loci. Nevertheless, we detect strong, recent and ongoing gene flow among the populations. Using genome scans and gene expression analysis we find that parallel evolution of flatwing on different islands is associated with shared genomic hotspots of adaptation that contain the gene doublesex, but the form of selection differs among islands and corresponds to known flatwing demographics in the wild. We thus show how parallel adaptation can occur on contemporary timescales despite gene flow, indicating that it could be less constrained than previously appreciated.


Assuntos
Adaptação Fisiológica/genética , Fluxo Gênico , Gryllidae/genética , Gryllidae/fisiologia , Animais , Regulação da Expressão Gênica no Desenvolvimento , Loci Gênicos , Variação Genética , Genética Populacional , Genoma de Inseto , Geografia , Hawaii , Ilhas , Masculino , Seleção Genética , Asas de Animais/anatomia & histologia
2.
Int J Mol Sci ; 21(24)2020 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-33371331

RESUMO

Many insects are capable of developing two types of wings (i.e., wing polyphenism) to adapt to various environments. Though the roles of microRNAs (miRNAs) in regulating animal growth and development have been well studied, their potential roles in modulating wing polyphenism remain largely elusive. To identify wing polyphenism-related miRNAs, we isolated small RNAs from 1st to 5th instar nymphs of long-wing (LW) and short-wing (SW) strains of the brown planthopper (BPH), Nilaparvata lugens. Small RNA libraries were then constructed and sequenced, yielding 158 conserved and 96 novel miRNAs. Among these, 122 miRNAs were differentially expressed between the two BPH strains. Specifically, 47, 2, 27 and 41 miRNAs were more highly expressed in the 1st, 3rd, 4th and 5th instars, respectively, of the LW strain compared with the SW strain. In contrast, 47, 3, 29 and 25 miRNAs were more highly expressed in the 1st, 3rd, 4th and 5th instars, respectively, of the SW strain compared with the LW strain. Next, we predicted the targets of these miRNAs and carried out Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analysis. We found that a number of pathways might be involved in wing form determination, such as the insulin, MAPK, mTOR, FoxO and thyroid hormone signaling pathways and the thyroid hormone synthesis pathway. Thirty and 45 differentially expressed miRNAs targeted genes in the insulin signaling and insect hormone biosynthesis pathways, respectively, which are related to wing dimorphism. Among these miRNAs, Nlu-miR-14-3p, Nlu-miR-9a-5p and Nlu-miR-315-5p, were confirmed to interact with insulin receptors (NlInRs) in dual luciferase reporter assays. These discoveries are helpful for understanding the miRNA-mediated regulatory mechanism of wing polyphenism in BPHs and shed new light on how insects respond to environmental cues through developmental plasticity.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento , Hemípteros/genética , Proteínas de Insetos/metabolismo , MicroRNAs/genética , Asas de Animais/anatomia & histologia , Animais , Perfilação da Expressão Gênica , Hemípteros/anatomia & histologia , Hemípteros/crescimento & desenvolvimento , Proteínas de Insetos/genética , Fenótipo , Transdução de Sinais , Transcriptoma , Asas de Animais/crescimento & desenvolvimento , Asas de Animais/metabolismo
3.
PLoS One ; 15(10): e0239620, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33125377

RESUMO

Flight morphological variations and its consequences on animal performance are common in winged insects. In the butterfly Heliconius charithonia, sex-related differences in the wing morphological design have been described resulting in differences in foraging behavior, daily flight distances and flight aerodynamics. It has been suggested that these differences should be reflected in the metabolic capacities and energetic budgets associated with flight in both sexes. In this study, we analyzed the relationship between wing morphological variation and metabolic performance, flight aerodynamics and energetic reserves in females and males of Heliconius charithonia over two years. The results confirm the presence of wing shape sexual dimorphism, but also show an unexpected sex-related annual variation in wing shape, mirrored in the metabolic condition (resting metabolic rate) of individuals. However, contrary to expectation, intersexual variations in wing shape are not related to differences between the sexes in terms of flight aerodynamics, flight metabolic rates, or energetic reserves (carbohydrates, lipids and proteins). Our results indicate a considerable plasticity in H. charithonia wing shape, which we suggest is determined by a trade-off between environmental pressures and reproductive restriction of each sex, maintaining an optimum flight design. Finally, similarities in metabolic rates between young and older males and females in both years may be a consequence of the ability of Heliconius species to feed on pollen.


Assuntos
Borboletas/anatomia & histologia , Borboletas/metabolismo , Voo Animal/fisiologia , Asas de Animais/anatomia & histologia , Animais , Metabolismo Basal , Evolução Biológica , Fenômenos Biofísicos , Borboletas/fisiologia , Metabolismo Energético , Feminino , Masculino , México , Caracteres Sexuais , Asas de Animais/fisiologia
4.
Chemosphere ; 261: 127787, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32750623

RESUMO

Drosophila is among the most commonly used models for toxicity assessment of different types of nanoparticles. This study aims to examine the effects of a constant exposure to the low concentration of human food grade titanium dioxide nanoparticles (TiO2 E171) on Drosophila melanogaster wing morphology over multiple generations. Subsequently, the Geometric Morphometrics Analysis was employed to examine possible changes in the wing shape and size of the treated flies. The treatment resulted in the diminishment but not a disruption in the sexual dimorphism in wings. Consequently, the female flies were clearly separated from the male flies by the differences in wing morphology as in the control group. A splitting by generations was overly similar within the control and the treatment, but it was slightly more pronounced in the treatment. However, the observed generational differences seemed mostly random between generations, irrespective of the treatment. Specifically, the treated groups displayed slightly higher splitting by generations in females than in males. Regardless of the generation, the results show a clear splitting by the differences in the wing shape between the treated flies and the flies from control. The mean value of centroid size, which refers to the wing size, of both female and male wings was smaller in the treatment when compared to the control. The overall effect of TiO2 was to induce significant difference in Drosophila wing morphology but it did not alter the general wing morphology pattern. Therefore, the change in the wings occurred only within the normally allowed wing variation.


Assuntos
Drosophila melanogaster/fisiologia , Nanopartículas/toxicidade , Titânio/toxicidade , Asas de Animais/efeitos dos fármacos , Animais , Drosophila , Drosophila melanogaster/efeitos dos fármacos , Feminino , Alimentos , Humanos , Masculino , Caracteres Sexuais , Asas de Animais/anatomia & histologia
5.
PLoS Comput Biol ; 16(8): e1008105, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32817654

RESUMO

Epithelial sheets define organ architecture during development. Here, we employed an iterative multiscale computational modeling and quantitative experimental approach to decouple direct and indirect effects of actomyosin-generated forces, nuclear positioning, extracellular matrix, and cell-cell adhesion in shaping Drosophila wing imaginal discs. Basally generated actomyosin forces generate epithelial bending of the wing disc pouch. Surprisingly, acute pharmacological inhibition of ROCK-driven actomyosin contractility does not impact the maintenance of tissue height or curved shape. Computational simulations show that ECM tautness provides only a minor contribution to modulating tissue shape. Instead, passive ECM pre-strain serves to maintain the shape independent from actomyosin contractility. These results provide general insight into how the subcellular forces are generated and maintained within individual cells to induce tissue curvature. Thus, the results suggest an important design principle of separable contributions from ECM prestrain and actomyosin tension during epithelial organogenesis and homeostasis.


Assuntos
Actomiosina/metabolismo , Epitélio/anatomia & histologia , Matriz Extracelular/metabolismo , Animais , Drosophila/anatomia & histologia , Drosophila/embriologia , Drosophila/metabolismo , Epitélio/metabolismo , Fosforilação , Asas de Animais/anatomia & histologia , Asas de Animais/embriologia , Asas de Animais/metabolismo
6.
PLoS One ; 15(8): e0228975, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32817690

RESUMO

In mosquitoes of medical importance, wing shape and size can vary with altitude, an aspect that can influence dispersion and, consequently, their vector capacity. Using geometric morphometry analysis, Aedes aegypti wing size and shape variation of males and females was studied in four altitudes in the second-smallest department in Colombia: 1,200 m (Tebaida), 1,400 m (Armenia), 1,500 m (Calarcá), and 1,700 m (Filandia). Wing shape in males (P < 0.001) and females (P < 0.001) was significantly different through the altitudinal gradient; in turn, wing size in males followed the altitudinal gradient males (R2 = 0.04946, P = 0.0002), females (R2 = 0.0011, P = 0.46). Wing allometry for males (P < 0.001) and females (P < 0.001) was significant. Likewise, the shape and size of the wings of males (P < 0.001) and females (P < 0.001) had significant fluctuating asymmetry. It is concluded that, in a small scale with an altitudinal variation of 500 meters, it is detected that the size and shape of the wings varied in A. aegypti, main vector the agents that cause dengue, chikungunya, and Zika. The fluctuating asymmetry is present in the individuals studied and could be associated with environmental effects caused by vector control campaigns present in some sampling locations.


Assuntos
Aedes/fisiologia , Asas de Animais/anatomia & histologia , Asas de Animais/fisiologia , Altitude , Animais , Febre de Chikungunya , Colômbia , Dengue , Feminino , Masculino , Mosquitos Vetores/anatomia & histologia , Infecção por Zika virus
7.
Arthropod Struct Dev ; 57: 100947, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32505064

RESUMO

The covering by scales of the wings of Lepidoptera contributes to multiple functions that are critical for their survival and reproduction. In order to gain a better understanding about their distribution, we have exhaustively studied 4 specimens of Colias crocea (Geoffroy, 1785). We have quantified the sources of variability affecting scale density. The results indicate that the scale covering of butterfly wings may be remarkably heterogeneous, and that the importance of the sources of variability differs between forewings and hindwings. Thus, in forewing the greatest variability occurs between sectors, while in the hindwings it occurs between sides, with a higher density of scales on the underside, considerably higher (almost 19%) than on the upperside. It seems likely that this difference has an adaptive value, as the hindwing underside is more exposed (in resting position) to predators. These results are in contrast with the generally accepted notion that scale covering is uniform and homogeneous. Moreover, the cover scale density is independent of the size of the specimen and therefore an average density of scales can be attributed to this species. According to our measurements C. crocea has 312 scales/mm2 and the total number of scales per individual is about 520,000 on average.


Assuntos
Escamas de Animais/anatomia & histologia , Borboletas/anatomia & histologia , Asas de Animais/anatomia & histologia , Animais , Feminino
8.
Folia Parasitol (Praha) ; 672020 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-32350157

RESUMO

In Thailand, Anopheles (Cellia) epiroticus Linton et Harbach (Diptera: Culicidae) is the secondary vector of human malaria along coastal regions. While there are some studies of phenotypic variability and population structure of A. epiroticus, more information on morphological variation would enhance epidemiological understanding of medically important mosquito vectors. This research examined morphological variation at three different distances from coastlines of Samut Songkhram Province, Thailand, using landmark-based geometric morphometrics. Wing shape of A. epiroticus was significantly different in the area 0.2 km away from the sea compared to areas 2 and 4 km away from the sea (p < 0.05). Phenotypic variability in wing shape is associated with distance from the sea. Morphological variations in the area closest to the sea were most pronounced, showing a relationship between A. epiroticus and the ecosystem that affects wing geometry. These results provide important information to understand morphological variation of A. epiroticus in coastal areas.


Assuntos
Anopheles/anatomia & histologia , Mosquitos Vetores/anatomia & histologia , Asas de Animais/anatomia & histologia , Animais , Malária , Plasmodium , Chuva , Estações do Ano , Tailândia
9.
PLoS Genet ; 16(5): e1008772, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32365064

RESUMO

In the postgenomics era, comparative genomics have advanced the understanding of evolutionary processes of neuropeptidergic signaling systems. The evolutionary origin of many neuropeptidergic signaling systems can be traced date back to early metazoan evolution based on the conserved sequences. Insect parathyroid hormone receptor (iPTHR) was previously described as an ortholog of vertebrate PTHR that has a well-known function in controlling bone remodeling. However, there was no sequence homologous to PTH sequence in insect genomes, leaving the iPTHR as an orphan receptor. Here, we identified the authentic ligand insect PTH (iPTH) for the iPTHR. The taxonomic distribution of iPTHR, which is lacking in Diptera and Lepidoptera, provided a lead for identifying the authentic ligand. We found that a previously described orphan ligand known as PXXXamide (where X is any amino acid) described in the cuttlefish Sepia officinalis has a similar taxonomic distribution pattern as iPTHR. Tests of this peptide, iPTH, in functional reporter assays confirmed the interaction of the ligand-receptor pair. Study of a model beetle, Tribolium castaneum, was used to investigate the function of the iPTH signaling system by RNA interference followed by RNA sequencing and phenotyping. The results suggested that the iPTH system is likely involved in the regulation of cuticle formation that culminates with a phenotype of defects in wing exoskeleton maturation at the time of adult eclosion. Moreover, RNAi of iPTHRs also led to significant reductions in egg numbers and hatching rates after parental RNAi.


Assuntos
Neuropeptídeos/metabolismo , Hormônio Paratireóideo/metabolismo , Receptores de Hormônios Paratireóideos/genética , Tribolium/anatomia & histologia , Animais , Evolução Molecular , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Fenótipo , Filogenia , Receptores de Hormônios Paratireóideos/metabolismo , Análise de Sequência de RNA , Tribolium/genética , Tribolium/metabolismo , Asas de Animais/anatomia & histologia
10.
Nat Commun ; 11(1): 2463, 2020 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-32424113

RESUMO

An organism's ability to disperse influences many fundamental processes, from speciation and geographical range expansion to community assembly. However, the patterns and underlying drivers of variation in dispersal across species remain unclear, partly because standardised estimates of dispersal ability are rarely available. Here we present a global dataset of avian hand-wing index (HWI), an estimate of wing shape widely adopted as a proxy for dispersal ability in birds. We show that HWI is correlated with geography and ecology across 10,338 (>99%) species, increasing at higher latitudes and with migration, and decreasing with territoriality. After controlling for these effects, the strongest predictor of HWI is temperature variability (seasonality), with secondary effects of diet and habitat type. Finally, we also show that HWI is a strong predictor of geographical range size. Our analyses reveal a prominent latitudinal gradient in HWI shaped by a combination of environmental and behavioural factors, and also provide a global index of avian dispersal ability for use in community ecology, macroecology, and macroevolution.


Assuntos
Migração Animal/fisiologia , Aves/anatomia & histologia , Ecossistema , Asas de Animais/anatomia & histologia , Animais , Filogeografia
11.
PLoS One ; 15(5): e0232601, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32392221

RESUMO

Morphological variation between individuals can increase niche segregation and decrease intraspecific competition when heterogeneous individuals explore their environment in different ways. Among bat species, wing shape correlates with flight maneuverability and habitat use, with species that possess broader wings typically foraging in more cluttered habitats. However, few studies have investigated the role of morphological variation in bats for niche partitioning at the individual level. To determine the relationship between wing shape and diet, we studied a population of the insectivorous bat species Pteronotus mesoamericanus in the dry forest of Costa Rica. Individual diet was resolved using DNA metabarcoding, and bat wing shape was assessed using geometric morphometric analysis. Inter-individual variation in wing shape showed a significant relationship with both dietary dissimilarity based on Bray-Curtis estimates, and nestedness derived from an ecological network. Individual bats with broader and more rounded wings were found to feed on a greater diversity of arthropods (less nested) in comparison to individuals with triangular and pointed wings (more nested). We conclude that individual variation in bat wing morphology can impact foraging efficiency leading to the observed overall patterns of diet specialization and differentiation within the population.


Assuntos
Quirópteros/anatomia & histologia , Asas de Animais/anatomia & histologia , Animais , Quirópteros/fisiologia , Costa Rica , Ecossistema , Feminino , Voo Animal , Florestas , Masculino , Comportamento Predatório , Especificidade da Espécie , Asas de Animais/fisiologia
12.
Proc Natl Acad Sci U S A ; 117(21): 11589-11596, 2020 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-32393634

RESUMO

Organisms have evolved endless morphological, physiological, and behavioral novel traits during the course of evolution. Novel traits were proposed to evolve mainly by orchestration of preexisting genes. Over the past two decades, biologists have shown that cooption of gene regulatory networks (GRNs) indeed underlies numerous evolutionary novelties. However, very little is known about the actual GRN properties that allow such redeployment. Here we have investigated the generation and evolution of the complex wing pattern of the fly Samoaia leonensis We show that the transcription factor Engrailed is recruited independently from the other players of the anterior-posterior specification network to generate a new wing pattern. We argue that partial cooption is made possible because 1) the anterior-posterior specification GRN is flexible over time in the developing wing and 2) this flexibility results from the fact that every single gene of the GRN possesses its own functional time window. We propose that the temporal flexibility of a GRN is a general prerequisite for its possible cooption during the course of evolution.


Assuntos
Drosophilidae , Regulação da Expressão Gênica no Desenvolvimento/genética , Redes Reguladoras de Genes/genética , Pigmentação/genética , Asas de Animais , Animais , Padronização Corporal/genética , Drosophilidae/genética , Drosophilidae/crescimento & desenvolvimento , Proteínas de Insetos/genética , Fatores de Transcrição/genética , Asas de Animais/anatomia & histologia , Asas de Animais/crescimento & desenvolvimento , Asas de Animais/fisiologia
13.
Mol Phylogenet Evol ; 149: 106822, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32294546

RESUMO

The evolution of flight triggered the rise of pterygote insects, but secondary flightlessness has evolved numerous times and is often associated with reduced gene flow among populations and patterns of diversification. With 85 species most of which are wing reduced, the ground beetle genus Trechus in the European Alps may be one such example. Here, we reconstructed a molecular phylogeny using 72 of these species based on mitochondrial and nuclear DNA sequences as a basis for reconstructing their evolutionary history. We rearranged the species into 20 monophyletic species groups, of which five are novel and 15 were already established but with different species allocated. Wing measurements revealed a strong tendency for wing reduction but also variation within and among species, with the few fully-winged species distributed across multiple species groups containing also wing-reduced species. Using character mapping and phylogenetic independent contrasts, we found that neither distribution area, body size, pigmentation, elevational zone, nor hygrophily explained wing status in our sample. Assessing five completely sampled clades, we inferred that each of their ancestors had most likely already been wing reduced. We discuss putative scenarios explaining this pattern and the presence of wing polymorphism across the phylogeny. One plausible scenario would be an already wing-reduced last common ancestor of all Trechus species and multiple regains of full wing length via back mutation and/or hybridisation. Alternatively and possibly more likely, the ancestors were either fully winged, with subsequent rapid and repeated wing reduction explaining the current wing-status pattern, or polymorphic, with long-term polymorphism or reselection acting on standing genetic variation explaining the recent fully-winged species. Either way, Trechus ground beetles are a promising, taxonomically and ecologically diverse system for studying the evolution of flightlessness. Areas for future research include morphological assessment of flight muscles, functional analysis of flight capability, and exploration of the mechanistic and genetic bases of wing and flight evolution.


Assuntos
Evolução Biológica , Besouros/anatomia & histologia , Besouros/classificação , Asas de Animais/anatomia & histologia , Animais , Europa (Continente) , Geografia , Filogenia , Pigmentação , Análise de Sequência de DNA , Especificidade da Espécie
14.
PLoS One ; 15(4): e0232193, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32348334

RESUMO

Insect wings are highly evolved structures with aerodynamic and structural properties that are not fully understood or systematically modeled. Most species in the insect order Odonata have permanently deployed high aspect ratio wings. Odonata have been documented to exhibit extraordinary flight performance and a wide range of interesting flight behaviors that rely on agility and efficiency. The characteristic three-dimensional corrugated structures of these wings have been observed and modeled for a small number of species, with studies showing that corrugations can provide significant aerodynamic and structural advantages. Comprehensive museum collections are the most practical source of Odonata wing, despite the risk of adverse effects caused by dehydration and preservation of specimens. Museum specimens are not to be handled or damaged and are best left undisturbed in their display enclosures. We have undertaken a systematic process of scanning, modeling, and post-processing the wings of over 80 Odonata species using a novel and accurate method and apparatus we developed for this purpose. The method allows the samples to stay inside their glass cases if necessary and is non-destructive. The measurements taken have been validated against micro-computed tomography scanning and against similar-sized objects with measured dimensions. The resulting publicly available dataset will allow aeronautical analysis of Odonata aerodynamics and structures, the study of the evolution of functional structures, and research into insect ecology. The technique is useable for other orders of insects and other fragile samples.


Assuntos
Odonatos/anatomia & histologia , Asas de Animais/anatomia & histologia , Animais , Bases de Dados Factuais , Voo Animal/fisiologia , Processamento de Imagem Assistida por Computador , Imageamento Tridimensional/instrumentação , Imageamento Tridimensional/métodos , Microscopia Eletrônica de Varredura , Modelos Anatômicos , Museus , Odonatos/classificação , Odonatos/fisiologia , Fotogrametria/instrumentação , Austrália do Sul , Asas de Animais/fisiologia , Asas de Animais/ultraestrutura , Microtomografia por Raio-X
15.
An Acad Bras Cienc ; 92 Suppl 1: e20181306, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32348412

RESUMO

The objective of this study was to evaluate the influence of wing bands and the behavior of Anastrepha fraterculus in the presence of Megafreya sutrix. The first experiment used specimens of M. sutrix (n = 40), 20 males and 20 females of A. fraterculus and Musca domestica. The second experiment used 20 individuals of M. sutrix (10 males and 10 females) and 120 of A. fraterculus (20 males and 20 females) for each treatment. Marks were made on the wings of the flies: a group with painted wing bands (n = 40) with their wings fully painted; another with highlighted wing bands (n = 40) and normal bands (n = 40). Recordings were made for 15 min or until the fly was preyed upon. The analyses were performed through observation of the recordings and Chi-square test with Yates correction for continuity. The values found for predation of A. fraterculus were significant when compared to M. domestica when evaluating the predation factor, showing that, A. fraterculus is less predated than M. domestica. It was found that the wing patterns did not influence the predatory behavior of M. sutrix.


Assuntos
Comportamento Predatório/fisiologia , Aranhas/fisiologia , Tephritidae/anatomia & histologia , Asas de Animais/anatomia & histologia , Animais , Feminino , Masculino , Tephritidae/fisiologia , Asas de Animais/fisiologia
16.
J Vis Exp ; (157)2020 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-32225164

RESUMO

Axon degeneration is a shared feature in neurodegenerative disease and when nervous systems are challenged by mechanical or chemical forces. However, our understanding of the molecular mechanisms underlying axon degeneration remains limited. Injury-induced axon degeneration serves as a simple model to study how severed axons execute their own disassembly (axon death). Over recent years, an evolutionarily conserved axon death signaling cascade has been identified from flies to mammals, which is required for the separated axon to degenerate after injury. Conversely, attenuated axon death signaling results in morphological and functional preservation of severed axons and their synapses. Here, we present three simple and recently developed protocols that allow for the observation of axonal morphology, or axonal and synaptic function of severed axons that have been cut-off from the neuronal cell body, in the fruit fly Drosophila. Morphology can be observed in the wing, where a partial injury results in axon death side-by-side of uninjured control axons within the same nerve bundle. Alternatively, axonal morphology can also be observed in the brain, where the whole nerve bundle undergoes axon death triggered by antennal ablation. Functional preservation of severed axons and their synapses can be assessed by a simple optogenetic approach coupled with a post-synaptic grooming behavior. We present examples using a highwire loss-of-function mutation and by over-expressing dnmnat, both capable of delaying axon death for weeks to months. Importantly, these protocols can be used beyond injury; they facilitate the characterization of neuronal maintenance factors, axonal transport, and axonal mitochondria.


Assuntos
Axônios/fisiologia , Drosophila melanogaster/fisiologia , Sinapses/fisiologia , Animais , Mutação , Doenças Neurodegenerativas/metabolismo , Neurônios/fisiologia , Optogenética , Transdução de Sinais , Asas de Animais/anatomia & histologia , Asas de Animais/fisiologia
17.
J Chem Ecol ; 46(4): 363-377, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32125582

RESUMO

Insects have evolved highly sensitive olfactory sensory systems to detect plant hosts and mates, with plant volatiles playing an important role in informing insect behavior. Chemosensory proteins (CSPs) are thought to play a key role in this process, but in this respect, there is limited information on brown planthopper Nilaparvata lugens, one of the most destructive pests of rice. To expand our understanding of CSP function in N. lugens we explored expression profiles and binding characteristics of NlugCSP3. The ligands with higher binding affinity were also validated by molecular docking and behavioral assays. NlugCSP3 mRNA was expressed at relatively higher levels in antennae and abdomen of 3-day-old unmated macropterous males as well as in antennae of 3-day mated macropterous and brachypterous females. Fluorescence competitive binding assays revealed that 5 out of 25 candidate volatiles are strong binders (Ki < 10 µM). Behavioral assays revealed that nonadecane and 2-tridecanone, which have high binding affinities in fluorescence competition-binding assays, displayed strong attractiveness to N. lugens. Pursuing this further, molecular docking analysis identified key amino acid residues involved in binding volatile compounds. Overall, our data provide a base for further investigation of the potential physiological functions of CSP3 in Nilaparvata lugens, and extend the function of NlugCSP3 in chemoreception of N. lugens.


Assuntos
Expressão Gênica , Hemípteros/genética , Proteínas de Insetos/genética , Compostos Orgânicos Voláteis/metabolismo , Fatores Etários , Aminoácidos/metabolismo , Animais , Antenas de Artrópodes/metabolismo , Feminino , Perfilação da Expressão Gênica , Hemípteros/química , Hemípteros/metabolismo , Proteínas de Insetos/metabolismo , Ligantes , Masculino , Simulação de Acoplamento Molecular , Reprodução , Fatores Sexuais , Asas de Animais/anatomia & histologia
18.
Am Nat ; 195(4): 733-742, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32216666

RESUMO

Communication requires both the encoding of information and its effective transmission, but little is known about display traits that primarily serve to enhance efficacy. Here we examined the visual courtships of Lispe cana, a cursorial fly that lives and mates in heterogeneous foreshores, and tested the prediction that males should seek to enhance signal salience and consequent fitness through the flexible choice of display locations. We show that courting males access the field of view of females by straddling them and holding their wings closed before moving ahead to present their structurally colored faces in ritualized dances. Males preferentially present these UV-white signals against darker backgrounds and the magnitude of contrast predicts female attention, which in turn predicts mating success. Our results demonstrate a striking interplay between the physical and attentional manipulation of receivers and reveal novel routes to the enhancement of signal efficacy in noisy environments.


Assuntos
Corte , Preferência de Acasalamento Animal , Muscidae/fisiologia , Animais , Cor , Feminino , Cabeça/anatomia & histologia , Masculino , Muscidae/anatomia & histologia , Percepção Visual , Asas de Animais/anatomia & histologia
19.
PLoS One ; 15(3): e0229120, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32130246

RESUMO

A remarkable new genus and species of Nemourinae, Sinonemura balangshana gen. et sp. n., is described from Balang Mountains, Sichuan, southwestern China. The description is based on morphology and molecular data. The Nemourinae genera related to the new taxon are re-evaluated on the basis of comparative functional morphology of male epiproct. Notes on the Asian distribution of the Nemourinae are also given.


Assuntos
Insetos/classificação , Neópteros/classificação , Filogenia , Distribuição Animal , Animais , China , Classificação/métodos , Demografia , Feminino , Especiação Genética , Cabeça/anatomia & histologia , Cabeça/crescimento & desenvolvimento , Insetos/anatomia & histologia , Insetos/crescimento & desenvolvimento , Masculino , Neópteros/anatomia & histologia , Neópteros/crescimento & desenvolvimento , Especificidade da Espécie , Asas de Animais/anatomia & histologia , Asas de Animais/crescimento & desenvolvimento
20.
Nat Commun ; 11(1): 1294, 2020 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-32157090

RESUMO

Recently, it has been shown that animals such as jumping spiders, birds, and butterflies have evolved ultra-black coloration comparable to the blackest synthetic materials. Of these, certain papilionid butterflies have reflectances approaching 0.2%, resulting from a polydisperse honeycomb structure. It is unknown if other ultra-black butterflies use this mechanism. Here, we examine a phylogenetically diverse set of butterflies and demonstrate that other butterflies employ simpler nanostructures that achieve ultra-black coloration in scales thinner than synthetic alternatives. Using scanning electron microscopy, we find considerable interspecific variation in the geometry of the holes in the structures, and verify with finite-difference time-domain modeling that expanded trabeculae and ridges, found across ultra-black butterflies, reduce reflectance up to 16-fold. Our results demonstrate that butterflies produce ultra-black by creating a sparse material with high surface area to increase absorption and minimize surface reflection. We hypothesize that butterflies use ultra-black to increase the contrast of color signals.


Assuntos
Escamas de Animais/anatomia & histologia , Borboletas/anatomia & histologia , Nanoestruturas/química , Pigmentação , Escamas de Animais/ultraestrutura , Animais , Borboletas/ultraestrutura , Simulação por Computador , Nanoestruturas/ultraestrutura , Refratometria , Asas de Animais/anatomia & histologia
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