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1.
J Insect Sci ; 19(4)2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31268546

RESUMO

Drosophila suzukii Matsumura (Diptera: Drosophilidae) is currently a major pest management challenge in berry and cherry production. This species has a winter morph phenotype with longer wings and increased melanization associated with survival in colder conditions. Measurements of wing morphology in Michigan D. suzukii collected during 2016 and 2017 showed that induction of this morph began in September and increased into December, correlated with decreasing temperature and day length. Importantly, we found that wing length increases along a continuous scale and there is overlap between the two morph types. We tested whether temperature or photoperiod elicited this phenotypic change using a factorial design with each preadult lifestage held at 10 or 25°C and 16:8 or 8:16 L:D. Our results support temperature as the main driver of transition to the winter morph for all immature stages. Comparing the reproductive capacity of winter morph flies in cold conditions and when previously acclimated to warm conditions, flies with the acclimation experience laid comparable numbers of eggs as the summer morphs at 25°C, indicating that winter morphs can reproduce after surviving cold periods. These results highlight the ability of D. suzukii to adapt to changing temperature conditions, allowing it to survive cold and also exploit warmer periods to build populations when conditions allow.


Assuntos
Aclimatação , Drosophila/fisiologia , Oviposição , Estações do Ano , Asas de Animais/anatomia & histologia , Animais , Drosophila/anatomia & histologia , Feminino , Masculino , Fenótipo , Fotoperíodo , Temperatura Ambiente
2.
Microsc Res Tech ; 82(10): 1741-1747, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31295381

RESUMO

In this work a single glycerol-water mixture, determined to be most apt at 30% (wt/vol), was used to immobilize Drosophila samples as well as to create a liquid lens for smartphone magnification viewing. This provides the advantage of being able to observe immobilized insects directly in the field rather than in the laboratory. In order to avoid having bubbles in the liquid lens and immobilizing medium that hinder visibility, an approach was developed where a stable pendant drop is moved in tandem with the dispensing tip by gravity and stopped abruptly so that sufficient momentum is transferred to the drop for its dislodgement. With 30% glycerol-water (wt/vol) mixtures, applying a minimal stroke of 10 mm with longitudinal impact delivered a momentum of 0.1464 N/s that allowed transfer of a preselected liquid volume for the processes.


Assuntos
Drosophila/anatomia & histologia , Entomologia/instrumentação , Entomologia/métodos , Microscopia/instrumentação , Microscopia/métodos , Smartphone , Animais
3.
BMC Evol Biol ; 19(1): 109, 2019 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-31132984

RESUMO

BACKGROUND: Male genitals have repeatedly evolved left-right asymmetries, and the causes of such evolution remain unclear. The Drosophila nannoptera group contains four species, among which three exhibit left-right asymmetries of distinct genital organs. In the most studied species, Drosophila pachea, males display asymmetric genital lobes and they mate right-sided on top of the female. Copulation position of the other species is unknown. RESULTS: To assess whether the evolution of genital asymmetry could be linked to the evolution of one-sided mating, we examined phallus morphology and copulation position in D. pachea and closely related species. The phallus was found to be symmetric in all investigated species except D. pachea, which displays an asymmetric phallus with a right-sided gonopore, and D. acanthoptera, which harbors an asymmetrically bent phallus. In all examined species, males were found to position themselves symmetrically on top of the female, except in D. pachea and D. nannoptera, where males mated right-sided, in distinctive, species-specific positions. In addition, the copulation duration was found to be increased in the nannoptera group species compared to closely related outgroup species. CONCLUSION: Our study shows that gains, and possibly losses, of asymmetry in genital morphology and mating position have evolved repeatedly in the nannoptera group. Current data does not allow us to conclude whether genital asymmetry has evolved in response to changes in mating position, or vice versa.


Assuntos
Evolução Biológica , Drosophila/anatomia & histologia , Drosophila/fisiologia , Genitália/anatomia & histologia , Comportamento Sexual Animal/fisiologia , Abdome/anatomia & histologia , Animais , Copulação/fisiologia , Feminino , Genitália Masculina/anatomia & histologia , Masculino , Filogenia , Especificidade da Espécie
4.
Elife ; 82019 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-31112130

RESUMO

Animals exhibit innate behaviours to a variety of sensory stimuli including olfactory cues. In Drosophila, one higher olfactory centre, the lateral horn (LH), is implicated in innate behaviour. However, our structural and functional understanding of the LH is scant, in large part due to a lack of sparse neurogenetic tools for this region. We generate a collection of split-GAL4 driver lines providing genetic access to 82 LH cell types. We use these to create an anatomical and neurotransmitter map of the LH and link this to EM connectomics data. We find ~30% of LH projections converge with outputs from the mushroom body, site of olfactory learning and memory. Using optogenetic activation, we identify LH cell types that drive changes in valence behavior or specific locomotor programs. In summary, we have generated a resource for manipulating and mapping LH neurons, providing new insights into the circuit basis of innate and learned olfactory behavior.


Assuntos
Comportamento Animal , Drosophila/anatomia & histologia , Drosophila/fisiologia , Corpos Pedunculados/anatomia & histologia , Corpos Pedunculados/fisiologia , Córtex Olfatório/anatomia & histologia , Córtex Olfatório/fisiologia , Animais , Conectoma , Vias Neurais/anatomia & histologia , Vias Neurais/fisiologia , Optogenética
5.
Eur Phys J E Soft Matter ; 42(4): 47, 2019 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-31011840

RESUMO

Drosophila wing discs show a remarkable variability when subject to mechanical perturbation. We developed a stretching bench that allows accurate measurements of instantaneous and time-dependent material behaviour of the disc as a whole, while determining the exact three-dimensional structure of the disc during stretching. Our experiments reveal force relaxation dynamics on timescales that are significant for development, along with a surprisingly nonlinear force-displacement relationship. Concurrently our imaging indicates that the disc is a highly heterogeneous tissue with a complex geometry. Using image-based 3D finite element modelling we are able to identify the contributions of size, shape and materials parameters to the measured force-displacement relations. In particular, we find that simulating the stretching of a disc with stiffness patterns in the extra-cellular matrix (ECM) recapitulates the experimentally found stretched geometries. In our simulations, linear hyperelasticity explains the measured nonlinearity to a surprising extent. To fully match the experimental force-displacement curves, we use an exponentially elastic material, which, when coupled to material relaxation also explains time-dependent experiments. Our simulations predict that as the disc develops, two counteracting effects, namely the discs foldedness and the hardening of the ECM lead to force-relative displacement curves that are nearly conserved during development.


Assuntos
Drosophila/anatomia & histologia , Elasticidade , Asas de Animais , Animais , Fenômenos Biomecânicos , Espaço Extracelular/metabolismo , Modelos Lineares , Dinâmica não Linear , Viscosidade , Asas de Animais/citologia
6.
Microsc Res Tech ; 82(7): 1145-1156, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30912875

RESUMO

Although scanning electron microscopy (SEM) has been broadly used for the examination of fixed whole insects or their hard exoskeleton-derived structures, including model organisms such as Drosophila, the routine use of SEM to evaluate vulnerable soft internal organs and tissues was often hampered by their fragile nature and frequent surface contamination. Here, we describe a simple four-step protocol that allows for the reliable and reproducible preparation of the larval and prepupal salivary glands (SGs) of Drosophila for SEM devoid of any surface contamination. The steps are to: first, proteolytically digest the adhering fat body; second, use detergent washes to remove contaminating coarse tissue fragments, including sticky remnants of the fat body; third, use nonionic emulsifying polysorbate emulsifiers to remove fine contaminants from the SGs surface; and fourth, use aminopolycarboxylate-based chelating agents to detach sessile hemocytes. Short but repeated rinses in 100 µL of a saline-based buffer between steps ensure efficient removal of remnants removed by each treatment. After these steps, the SGs are fixed in glutaraldehyde, postfixed in osmium tetroxide, dehydrated, critically point-dried, mounted on aluminum stubs, sputter coated with gold-palladium alloy and examined in the SEM.


Assuntos
Drosophila/anatomia & histologia , Larva/anatomia & histologia , Microscopia Eletrônica de Varredura , Glândulas Salivares/ultraestrutura , Fixação de Tecidos/métodos , Animais , Reprodutibilidade dos Testes
7.
J Insect Sci ; 18(6)2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-30445636

RESUMO

Life history parameters are used to estimate population dynamics, mortality, and reproduction in insects relative to their surrounding environment. For Drosophila suzukii Matsumura (Diptera: Drosophilidae), an invasive agricultural pest, previous studies have estimated net reproductive rate (Ro), generation time (T), and intrinsic rate of population increase (rm). A main limitation is that these estimates were measured under relatively favorable settings, and do not reflect environmental conditions and physiological states encountered during dormancy periods. Therefore, this study investigated the impacts of 1) low temperatures and 2) dietary protein: carbohydrate ratios (P:C) on both survival and fecundity parameters of D. suzukii summer morphs (SM) and postoverwintering winter morphs (WM) over physiological age (degree-days, DD). In both morphs, reproductive rates were higher and lifespan was longer when flies were exposed to low protein (P:C 1:4) or carbohydrate-only diets (P:C 0:1) compared with high protein diets (P:C 1:1). WM had higher reproductive rates and longer generation times than SM on optimal 1:4 diet in all trialed temperatures, but at the lowest temperatures, SM had higher reproductive rates than WM in carbohydrate-only and high protein diets. This likely reflected delayed oogenesis and hindered reproduction after an overwintering period in WM receiving suboptimal diets. Oviposition for SM and WM receiving 1:4 diet commenced from 0 to 100 DD, and peaked between 400 and 500 DD, earlier than flies receiving 0:1 diet. These results suggest that dietary protein has a crucial role in early oogenesis, particularly for postoverwintering WM. The parameters developed here reflect the population dynamics of D. suzukii before and after the crop growing season, an essential time for population buildup, survival, and early and late host infestation.


Assuntos
Temperatura Baixa , Dieta , Drosophila/fisiologia , Fertilidade/fisiologia , Animais , Drosophila/anatomia & histologia , Análise de Sobrevida
8.
Nat Commun ; 9(1): 4620, 2018 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-30397306

RESUMO

Epithelial folding transforms simple sheets of cells into complex three-dimensional tissues and organs during animal development. Epithelial folding has mainly been attributed to mechanical forces generated by an apically localized actomyosin network, however, contributions of forces generated at basal and lateral cell surfaces remain largely unknown. Here we show that a local decrease of basal tension and an increased lateral tension, but not apical constriction, drive the formation of two neighboring folds in developing Drosophila wing imaginal discs. Spatially defined reduction of extracellular matrix density results in local decrease of basal tension in the first fold; fluctuations in F-actin lead to increased lateral tension in the second fold. Simulations using a 3D vertex model show that the two distinct mechanisms can drive epithelial folding. Our combination of lateral and basal tension measurements with a mechanical tissue model reveals how simple modulations of surface and edge tension drive complex three-dimensional morphological changes.


Assuntos
Drosophila/crescimento & desenvolvimento , Células Epiteliais/citologia , Epitélio/anatomia & histologia , Epitélio/embriologia , Morfogênese , Estresse Mecânico , Actinas/metabolismo , Actomiosina , Amidas/antagonistas & inibidores , Animais , Fenômenos Biomecânicos , Padronização Corporal/genética , Divisão Celular , Proliferação de Células , Forma Celular , Tamanho Celular , Drosophila/anatomia & histologia , Drosophila/embriologia , Drosophila/genética , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Células Epiteliais/efeitos dos fármacos , Epitélio/efeitos dos fármacos , Matriz Extracelular , Discos Imaginais/crescimento & desenvolvimento , Larva/citologia , Larva/metabolismo , Terapia a Laser , Modelos Anatômicos , Modelos Biológicos , Piridinas/antagonistas & inibidores
9.
J Morphol ; 279(12): 1725-1752, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30397938

RESUMO

Ecological diversification of the endemic Hawaiian Drosophilidae has been accompanied by striking divergence in egg morphology, and ovarian structure and function. To determine how these flies successfully oviposit in a variety of breeding substrates, we used Scanning Electron Microscopy to examine the ultrastructure of the ovipositor of a sample of 65 Drosophila species and five Scaptomyza species of this hyperdiverse monophyletic group. The Drosophila species analyzed included representatives of the fungus-breeding haleakalae group, the leaf-breeding antopocerus and modified tarsus groups, the modified mouthparts species group, the nudidrosophila, and the picture wing clade; the latter sample of 41 species from four species groups included stem- and bark-breeders, as well as tree sap flux-breeders. Ovipositor length was found to vary more than 12-fold among Hawaiian drosophilids, with the longest ovipositors observed in the bark-breeding species and the shortest among the Scaptomyza and fungus-breeders. More noteworthy is the striking variation in overall shape and proportions of the ovipositor, in the shape of the apical region, and in the pattern of sensory structures or ovisensilla. Ultrastructural observations of the pair of long subapical sensilla on the ventral side identify these, for the first time, as taste bristles. Ovipositor form correlates strongly with the oviposition substrate used by the species, being of a distinctive shape and size in each case. We infer that the observed morphological divergence in the ovipositor is adaptive and the product of natural selection for successful reproduction in alternate microhabitats. The array of ovipositor forms that have evolved among the Hawaiian Drosophila species represent a series of ecomorphs that along with other divergent traits of the female reproductive system, have contributed to the successful adaptive radiation of this remarkable fauna.


Assuntos
Adaptação Fisiológica , Evolução Biológica , Drosophila/anatomia & histologia , Drosophila/ultraestrutura , Oviposição/fisiologia , Animais , Tamanho Corporal , Feminino , Fenótipo , Filogenia , Reprodução , Sensilas/anatomia & histologia , Sensilas/ultraestrutura , Especificidade da Espécie , Asas de Animais/anatomia & histologia , Asas de Animais/ultraestrutura
10.
Environ Entomol ; 47(6): 1365-1375, 2018 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-30395182

RESUMO

Drosophila suzukii (Matsumura) is an invasive pest of soft-skinned fruits that has caused significant economic damage worldwide. In this study, we focused on the seasonal abundance of D. suzukii during the early years of establishment in Wisconsin. We explored the seasonal patterns of summer and winter morphs, their reproductive output, and the effect temperature and humidity may have on their seasonal phenology. The seasonal abundance of D. suzukii during 2 yr (2014-2015) revealed that flies were detected in Wisconsin from early July to late December, with winter morphs being trapped from August through December. The adult populations trapped spanned 1 mo longer in 2015 than in 2014. The peak proportional abundance of D. suzukii in 2015 was recorded in August which was about 2 mo earlier than that in 2014. The combined factor [maximum temperature and maximum humidity] explained the most amount of variation in D. suzukii abundance consistently across the 2 yr in Wisconsin. We did not find significant differences in the fat content, number of mature eggs, proportion of females with immature eggs, or proportion of mated females between summer morph females at the beginning, summer and winter morph females during the middle, or winter morph females at the end of the collecting season in 2015. Our results build on the body of work providing a better understanding of the D. suzukii-overwintering abilities and strengthen the importance of early crop risk assessment and targeted control strategies.


Assuntos
Drosophila/fisiologia , Estações do Ano , Animais , Drosophila/anatomia & histologia , Feminino , Umidade , Masculino , Reprodução , Temperatura Ambiente
11.
Curr Biol ; 28(21): 3450-3457.e13, 2018 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-30344115

RESUMO

Diverse traits often covary between species [1-3]. The possibility that a single mutation could contribute to the evolution of several characters between species [3] is rarely investigated as relatively few cases are dissected at the nucleotide level. Drosophila santomea has evolved additional sex comb sensory teeth on its legs and has lost two sensory bristles on its genitalia. We present evidence that a single nucleotide substitution in an enhancer of the scute gene contributes to both changes. The mutation alters a binding site for the Hox protein Abdominal-B in the developing genitalia, leading to bristle loss, and for another factor in the developing leg, leading to bristle gain. Our study suggests that morphological evolution between species can occur through a single nucleotide change affecting several sexually dimorphic traits. VIDEO ABSTRACT.


Assuntos
Evolução Biológica , Proteínas de Drosophila/genética , Drosophila/anatomia & histologia , Drosophila/genética , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Homeodomínio/genética , Animais , Sítios de Ligação , Proteínas de Drosophila/metabolismo , Evolução Molecular , Genitália Masculina/anatomia & histologia , Proteínas de Homeodomínio/metabolismo , Masculino , Mutação , Nucleotídeos/genética
12.
Microscopy (Oxf) ; 67(6): 367-370, 2018 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-30272156

RESUMO

In transmission electron microscopy (TEM), silicon nitride (SiN) films are widely used as sample-supporting films owing to their robustness. We fabricated large-scale SiN films deposited by low-pressure chemical vapor deposition (LPCVD). This preparation method is advantageous for large window areas, since it yields films with control over properties such as tension and thickness. We fabricated large SiN windows for mounting large ultrathin sections and for acquiring large-area TEM images. Thus, sample sections sliced by conventional sample preparation techniques were successfully mounted on these sample-supporting films. We successfully obtained a 680 × 250 µm2 TEM montage image of a whole Drosophila embryo.


Assuntos
Microscopia Eletrônica de Transmissão/métodos , Compostos de Silício , Manejo de Espécimes/instrumentação , Animais , Drosophila/anatomia & histologia , Manejo de Espécimes/métodos
13.
Proc Biol Sci ; 285(1887)2018 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-30257912

RESUMO

Limited attention has been given to ecological factors influencing the coevolution of male and female genitalia. The innovative ovipositor of Drosophila suzukii, an invading fruit pest, represents an appealing case to document this phenomenon. The serrated saw-like ovipositor is used to pierce the hard skin of ripening fruits that are not used by other fruit flies that prefer soft decaying fruits. Here, we highlight another function of the ovipositor related to its involvement in genital coupling during copulation. We compared the morphology and coupling of male and female genitalia in this species to its sibling species, Drosophila subpulchrella, and to an outgroup species, Drosophila biarmipes These comparisons and a surgical manipulation indicated that the shape of male genitalia in D. suzukii has had to be adjusted to ensure tight coupling, despite having to abandon the use of a hook-like structure, paramere, because of the more linearly elongated ovipositor. This phenomenon demonstrates that ecological niche exploitation can directly affect the mechanics of genital coupling and potentially cause incompatibility among divergent forms. This model case provides new insights towards elucidating the importance of the dual functions of ovipositors in other insect species that potentially induce genital coevolution and ecological speciation.


Assuntos
Copulação , Drosophila/anatomia & histologia , Genitália Feminina/anatomia & histologia , Genitália Masculina/anatomia & histologia , Animais , Evolução Biológica , Ecossistema , Feminino , Frutas/parasitologia , Masculino , Oviposição , Especificidade da Espécie
14.
Evolution ; 72(11): 2406-2418, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30198555

RESUMO

Mechanical incompatibility of male and female genitalia is common in animals with internal fertilization. However, our knowledge regarding the precise mechanisms is limited. One key question regards the susceptibility of the match between male and female genitalia to morphological modification. To address this issue, we generated six different second-chromosome introgression lines possessing partially Drosophila mauritiana-like genital morphology in multiple structures in D. simulans background. Three of the six introgression males showed elevated mobility at some stages during copulation with D. simulans females; this was assumed to be an indication of genital mismatch. Notably, one of the introgression males with D. mauritiana-like enlarged anal plates showed occasional leakage of adhesive ejaculate on the body surface when mated with pure D. simulans females, suggesting apparent structural incompatibility in genital coupling. These observations suggested that both sexual and natural selection shape the anal plate morphology, highlighting the role of this structure as an important component of mechanical isolation. Partial replacement (introgression) by a sibling species genome can induce perturbations in genital coupling mechanics, suggesting that genital compatibility can be susceptible to subtle genomic changes at the early stages of divergence in these species.


Assuntos
Copulação , Drosophila/anatomia & histologia , Genitália Masculina/anatomia & histologia , Animais , Drosophila/genética , Feminino , Masculino , Sêmen , Especificidade da Espécie
15.
Curr Opin Neurobiol ; 52: 156-164, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30029143

RESUMO

A network of a few hundred neurons in the Drosophila central complex carries an estimate of the fly's heading in the world, akin to the mammalian head-direction system. Here we describe how anatomically defined neuronal classes in this network are poised to implement specific sub-processes for building and updating this population-level heading signal. The computations we describe in the fly central complex strongly resemble those posited to exist in the mammalian brain, in computational models for building head-direction signals. By linking circuit anatomy to navigational physiology, the Drosophila central complex should provide a detailed example of how a heading signal is built.


Assuntos
Encéfalo/fisiologia , Drosophila/fisiologia , Cabeça/fisiologia , Rede Nervosa/fisiologia , Neurônios/fisiologia , Navegação Espacial/fisiologia , Animais , Encéfalo/anatomia & histologia , Drosophila/anatomia & histologia , Rede Nervosa/anatomia & histologia
16.
J Therm Biol ; 75: 62-68, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30017053

RESUMO

Drosophila suzukii (Matsumura, 1931) is a highly successful invasive dipteran which represents a serious threat for global fruit industry. Among other adaptive traits, D. suzukii owes its success to the derived morphological features of its ovipositor, which allows the insect to exploit the exclusive ecological niche of fresh fruit, thus avoiding competition with other closely related species. With the aim of investigating temperature-induced phenotypic plasticity of D. suzukii ovipositor, we reared this insect in four different laboratory conditions, represented by the combination of two developmental temperatures and two diet regimes for the larvae. We recorded the effects of these two factors on ovipositor size and shape and overall body size through a combination of distance-based and geometric morphometric analyses. Results showed that insects attain the largest body sizes at lower temperature, whereas the diet does not determine significant difference in size. However, the effect on size of the two factors is less pronounced in the ovipositor, which shows a negative allometry with respect to body size in all treatments. At higher temperature, ovipositor shape tends also to co-vary with its own size. Neither temperature nor diet have significant effect on ovipositor bilateral fluctuating asymmetry. These results confirm the hypothesis that in D. suzukii the toughened valve of the ovipositor are subjected to effective morpho-functional constraints, while probably being under strong selection by reason of their mechanical role.


Assuntos
Drosophila/anatomia & histologia , Oviposição , Temperatura Ambiente , Animais , Tamanho Corporal , Feminino , Espécies Introduzidas , Larva , Fenótipo
17.
Neural Dev ; 13(1): 11, 2018 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-29875010

RESUMO

A striking feature of neural circuit structure is the arrangement of neurons into regularly spaced ensembles (i.e. columns) and neural connections into parallel layers. These patterns of organization are thought to underlie precise synaptic connectivity and provide a basis for the parallel processing of information. In this article we discuss in detail specific findings that contribute to a framework for understanding how columns and layers are assembled in the Drosophila visual system, and discuss their broader implications.


Assuntos
Drosophila/anatomia & histologia , Rede Nervosa/fisiologia , Neurônios/fisiologia , Vias Visuais/anatomia & histologia , Animais , Sinapses/fisiologia
18.
G3 (Bethesda) ; 8(7): 2399-2409, 2018 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-29844017

RESUMO

Quantitative genetic variation in morphology is pervasive in all species and is the basis for the evolution of differences among species. The measurement of morphological form in adults is now beginning to be combined with comparable measurements of form during development. Here we compare the shape of the developing wing to its adult form in a holometabolous insect, Drosophila melanogaster We used protein expression patterns to measure shape in the developing precursors of the final adult wing. Three developmental stages were studied: late larval third instar, post-pupariation and in the adult fly. We studied wild-type animals in addition to mutants of two genes (shf and ds) that have known effects on adult wing shape and size. Despite experimental noise related to the difficulty of comparing developing structures, we found consistent differences in wing shape and size at each developmental stage between genotypes. Quantitative comparisons of variation arising at different developmental stages with the variation in the final structure enable us to determine when variation arises, and to generate hypotheses about the causes of that variation. In addition we provide linear rules allowing us to link wing morphology in the larva, with wing morphology in the pupa. Our approach provides a framework to analyze quantitative morphological variation in the developing fly wing. This framework should help to characterize the natural variation of the larval and pupal wing shape, and to measure the contribution of the processes occurring during these developmental stages to the natural variation in adult wing morphology.


Assuntos
Variação Biológica da População/genética , Drosophila/crescimento & desenvolvimento , Drosophila/genética , Morfogênese/genética , Organogênese/genética , Asas de Animais/crescimento & desenvolvimento , Animais , Drosophila/anatomia & histologia , Feminino , Estudos de Associação Genética , Genótipo , Estágios do Ciclo de Vida , Masculino , Mutação , Fenótipo , Asas de Animais/anatomia & histologia
19.
J Vis Exp ; (131)2018 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-29443109

RESUMO

Diversified species of Drosophila (fruit fly) provide opportunities to study mechanisms of development and genetic changes responsible for evolutionary changes. In particular, the adult stage is a rich source of morphological traits for interspecific comparison, including wing pigmentation comparison. To study developmental differences among species, detailed observation and appropriate staging are required for precise comparison. Here we describe protocols for staging of pupal periods and quantification of wing pigmentation in a polka-dotted fruit fly, Drosophila guttifera. First, we describe the method for detailed morphological observation and definition of pupal stages based on morphologies. This method includes a technique for removing the puparium, which is the outer chitinous case of the pupa, to enable detailed observation of pupal morphologies. Second, we describe the method for measuring the duration of defined pupal stages. Finally, we describe the method for quantification of wing pigmentation based on image analysis using digital images and ImageJ software. With these methods, we can establish a solid basis for comparing developmental processes of adult traits during pupal stages.


Assuntos
Proteínas de Drosophila/metabolismo , Drosophila/fisiologia , Asas de Animais/anatomia & histologia , Asas de Animais/metabolismo , Animais , Drosophila/anatomia & histologia , Drosophila/crescimento & desenvolvimento , Drosophila/metabolismo , Pigmentação , Pupa , Asas de Animais/crescimento & desenvolvimento
20.
J Econ Entomol ; 111(2): 741-746, 2018 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-29415132

RESUMO

Drosophila suzukii (Matsumura, 1931) (Diptera: Drosophilidae) is a widely distributed pest of soft-skinned and stone fruits that is controlled mainly with pesticides. An alternative to the chemical control is the sterile insect technique (SIT), an ecologically friendly method of pest management that could be used against D. suzukii. The objective of the present study was to evaluate the effects of gamma radiation on reproductive sterility, ovarian morphometry, and quality parameters of D. suzukii. Full female sterility was achieved at 75 Gy, while an adequate level of male sterility (99.67%) was obtained at 200 Gy. The ovarian size showed an exponential decay in function of irradiation dose increase. There was no significant influence of irradiation dose on the quality parameters evaluated. Our data suggest that gamma radiation can be recommended to be used in an SIT program for D. suzukii.


Assuntos
Drosophila/efeitos da radiação , Raios gama , Controle de Insetos/métodos , Animais , Drosophila/anatomia & histologia , Drosophila/fisiologia , Feminino , Fertilidade/efeitos da radiação , Masculino , Ovário/anatomia & histologia , Ovário/efeitos da radiação , Doses de Radiação
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