Fly Wing Research Articles

Phenotypic divergence of Glossina morsitans (Diptera: Glossinidae) populations in Zambia: Application of landmark-based wing geometric morphometrics to discriminate population-level variation.

An important consequence of the discontinuous distribution of insect populations within their geographic range is phenotypic divergence. Detection of this divergence can be challenging when it occurs through subtle shifts in morphological traits with complex geometries, such as insect wing venation. Here, we used landmark-based wing geometric morphometrics to investigate the population-level phenotypic variation of the two subspecies of Glossina morsitans, G. m. centralis Machado and G. m. morsitans Westwood that occur in Zambia. Twelve homologous landmarks digitised on the right wings of 720 specimens collected from four and five sites (80 per site with 1:1 sex ratio) within the G. m. centralis and G. m. morsitans range respectively, were subjected to generalised Procrustes analysis to obtain wing centroid size (CS) and wing shape variables. Linear permutation models and redundancy analysis were then used to compare CS and wing shape between male and female G. morsitans, the two subspecies G. m. centralis and G. m. morsitans, the sexes of each subspecies and between sample locations within each subspecies range, respectively. Significant differences in CS and wing shape were observed between G. morsitans sexes, subspecies and sample locations within each subspecies range. A neighbour-joining cladogram derived from the analysis of Procrustes distances showed that tsetse within each subspecies range were highly divergent. We conclude that G. morsitans populations in Zambia exhibit significant population-level variation in fly size and wing shape which suggests high levels of population structuring. The main drivers of this structuring could be random genetic drift in G. m. centralis demes and local adaptation to environmental conditions in G. m. morsitans populations. We therefore recommend molecular studies to estimate the levels of gene flow between these populations and identify possible barriers to genetic flow.

Identifications of three novel alleles of Serrate in Drosophila

The Notch signaling pathway, an evolutionarily highly conserved pathway, participates in various essential physiological processes in organisms. Activation of Notch signaling in the canonical manner requires the combination of ligand and receptor. There are two ligands of Notch in Drosophila: Delta (Dl) and Serrate (Ser). A mutation mf157 is identified for causing nicks of fly wings in genetic analysis from a mutant library (unpublished) that was established previously. Immunofluorescent staining illustrates that mf157 represses the expression of Cut and Wingless (Wg), the targets of Notch signaling. MARCM cloning analysis reveals that mf157 functions at the same level or the upstream of ligands of Notch in signaling sending cells. Sequencing demonstrates that mf157 is a novel allele of the Ser gene. Subsequently, mf553 and mf167 are also identified as new alleles of Ser from our library. Furthermore, the complementary assays and the examination of transcripts confirm the sequencing results. Besides, the repressed phenotypes of Notch signaling were reverted by transposon excision experiments of mf157. In conclusion, we identify three fresh alleles of Ser. Our works supply additional genetic resources for further study of functions of Ser and Notch signaling regulation.

Investigation of the antiadhesive properties of biomimetic titanium nanostructures in fluidic flow

Abstract Within this work, the bacterial adhesion on biomimetic titanium nanostructures is investigated in fluidic flow. The motile, gram-negative bacteria strain Escherichia coli was used for the experiments and was incubated on nanostructured titanium, polished titanium and on the wings of the dragonfly Neuorbasis kaupi. After incubation period different flow velocities have been applied and the reduction of adhered bacteria was determined via fluorescence microscopy. Results show that nanostructured titanium surfaces have the ability to reduce the bacterial contamination as it is for the dragon fly wings used in this study. This behavior can also be predicted by analyzing the bearing area of the nanotopography which describes the actual part of the topography which is in contact to the bacteria.

Analysis of Synthetic Notch activation in Clonal Cell Populations in the Fly Wing Using Different Promoters

Analysis of Synthetic Notch activation in Clonal Cell Populations in the Fly Wing Using Different Promoters

Al-I'jāz al-Ilmī 'an Khalqi aż-żubab fī Al-Qur'an 'inda Ṭanṭāwī Jauharī

There are so many scientific signs in the Qur’an. Including scientific cues in verses that talk about insects. One of the insects recorded in the Qur’an is a fly, even the Qur’an directly relates the creation of this fly to a theological problem. This paper seeks to explore scientific wisdom in the verse regarding the creation of flies which are often underestimated by humans because of their existence which is considered not to bring benefits but on the contrary as a source of disease according to Thantawi Jauhari. Research using the descriptive approach has several conclusions, including that Thantawi Jauhari explained the unique design of the fly's limbs, especially the fly's eyes and wings. Flies also help reduce airborne diseases and fungi that can cause more severe illnesses in humans. In addition, Thantawi also tried to explain the wisdom of the creation of flies. The verse about the design of flies shows how weak humans are before God, especially statues worshippers.

Juan Modolell (1937-2023).

Juan Modolell (1937-2023).

Developmental bias predicts 60 million years of wing shape evolution

The degree to which developmental biases affect trait evolution is subject to much debate. Here, we first quantify fluctuating asymmetry as a measure of developmental variability, i.e., the propensity of developmental systems to create some phenotypic variants more often than others, and show that it predicts phenotypic and standing genetic variation as well as deep macroevolutionary divergence in wing shape in sepsid flies. Comparing our data to the findings of a previous study demonstrates that developmental variability in the sepsid fly Sepsis punctum strongly aligns with mutational, standing genetic, and macroevolutionary variation in the Drosophilidae--a group that diverged from the sepsid lineage ca. 64 My ago. We also find that developmental bias in S. punctum wing shape aligns with the effects of allometry, but less so with putatively adaptive thermal plasticity and population differentiation along latitude. Our findings demonstrate that developmental bias in fly wings predicts evolvability and macroevolutionary trajectories on a much greater scale than previously appreciated but also suggest that causal explanations for such alignments may go beyond simple constraint hypotheses.

Track Dating Hadith Fly Wings

This study explored and analyzed fly wings from the perspectives of hadith and science. It used a qualitative, analytical descriptive approach and integrated Harald Motzki's Isnad Cum Matn analysis with pharmaceutical studies. The research question was: How do hadith and pharmacy view fly wings? The results showed that 21 hadith books mention fly wings, including Sahih Bukhari. The hadith of the fly wings is valid, with Utbah bin Muslim as the common link (disseminator of hadith). From the perspective of pharmaceutical science, most microorganisms on flies, such as germs, viruses, and microbes, can cause diseases. However, drowning flies can neutralize these microorganisms against the fluid they perceive. This shows that science is in harmony with the hadith of the Prophet.

RNAi screen in the Drosophila wing of genes encoding proteins related to cytoskeleton organization and cell division

Cell division and cytoskeleton organization are fundamental processes participating in the development of Drosophila imaginal discs. In this manuscript we describe the phenotypes in the adult fly wing generated by knockdowns of 85% of Drosophila genes encoding proteins likely related to the regulation of cell division and cytoskeleton organization. We also compile a molecular classification of these proteins into classes that describe their expected or known main biochemical characteristics, as well as mRNA expression in the wing disc and likely protein subcellular localization for a subset of these genes. Finally, we analyze in more detail one protein family of cytoskeleton genes (Arp2/3 complex), and define the consequences of interfering with cell division for wing growth and patterning.

Wing Morphometrics of Forensic Important Fly Species in Kelantan, Malaysia

This research discusses the possibility of determining the species and sex of necrophagous flies by examining their wing morphology. Fresh beef meat (500 g) was placed in both rural and urban areas of Kelantan, Malaysia, and third instar maggots were collected for rearing from the third to the seventh day. Adult flies were killed with chloroform and their species and sexual status were determined using standard procedures. After detaching their wings, the morphology was documented using a Leica MC 170HD digital camera attached to a Leica stereo microscope. Thirteen wing landmarks were chosen for geometric morphometric analysis. Principal Component Analysis (PCA), canonical variate analysis (CVA), centroid size variation, and the unweighted pair-group method with arithmetic averages (UPGMA) were used to analyse the wing morphology of Chyrsomya megacephala (Fabricius, 1794), Chrysomya rufifacies (Macquart, 1843), and Sarcophaga ruficornis (Fabricius, 1794) The results indicate that sex and fly species can be distinguished based on wing morphology, and that CVA is more effective at species differentiation than sex grouping using Malahanobis distances, with a P value of 0.0001. When comparing different species and sexes of the fly, CVA demonstrates distinct clustering. Identification of necrophagous fly wings is a useful alternative tool for fly classification.

Blue as an Abstraction of Carmel

Blue as an Abstraction of Carmel Robert Dorsett A man who looked for the worldbeneath the blue, without blue . . . —Wallace Stevens The blue of the sea, the shadowsthat fall beneath the skirts of water,the larkspur, lupine of the valleys,gnat-like flocks of thyme.The blue gas jets of rosemary,the lichen upon the sea break boulders,fly wing panes, tide-pools, theirshallows blended with gentian, plum gray fogsabove the cliff wash, and noon sky’s blaze,purpura of the evenings . . . And beyond the land spit—in theclarity of those waters—the blue beneaththe blue unworkable in metaphor. [End Page 112] The Woman Who Speaks My Words If you doubt the woman whospeaks my words, hesitate before heras before a rhetorical device, not knowing whether sheaccompanies me or I’m alone, then listen: She speaks,yet I have my say, and now it’s me, and yet again she, untilout of the fragments of our contradictory play, asingle voice devolves, and you know it’s not only she who speaksnor I who love alone. [End Page 113] Robert Dorsett Berkeley, California Copyright © 2023 Johns Hopkins University Press

Learning Probabilistic Piecewise Rigid Atlases of Model Organisms via Generative Deep Networks.

Atlases are crucial to imaging statistics as they enable the standardization of inter-subject and inter-population analyses. While existing atlas estimation methods based on fluid/elastic/diffusion registration yield high-quality results for the human brain, these deformation models do not extend to a variety of other challenging areas of neuroscience such as the anatomy of C. elegans worms and fruit flies. To this end, this work presents a general probabilistic deep network-based framework for atlas estimation and registration which can flexibly incorporate various deformation models and levels of keypoint supervision that can be applied to a wide class of model organisms. Of particular relevance, it also develops a deformable piecewise rigid atlas model which is regularized to preserve inter-observation distances between neighbors. These modeling considerations are shown to improve atlas construction and key-point alignment across a diversity of datasets with small sample sizes including neuron positions in C. elegans hermaphrodites, fluorescence microscopy of male C. elegans, and images of fruit fly wings. Code is accessible at https://github.com/amin-nejat/Deformable-Atlas.

Deconstructing a visual signal: the role of motion and colour in predator deterrence.

Visual animal communication, whether to the same species or to other species, is largely conducted through dynamic and colourful signals. For a signal to be effective, the signaller must capture and retain the attention of the receiver. Signal efficacy is also dependent on the sensory limitations of the receiver. However, most signalling studies consider movement and colour separately, resulting in a partial understanding of the signal in question. We explored the structure and function of predator-prey signalling in the jumping spider-tephritid fly system, where the prey performs a wing waving display that deters an attack from the predator. Using a custom-built spider retinal tracker combined with visual modelling, and behavioural assays, we studied the effect of fly wing movement and colour on the jumping spider's visual system. We show that jumping spiders track their prey less effectively during wing display and this can be attributed to a series of fluctuations in chromatic and achromatic contrasts arising from the wing movements. These results suggest that displaying flies deter spider attacks by manipulating the movement biases of the spider's visual system. Our results emphasise the importance of receiver attention on the evolution of interspecific communication.

Sensing of a spore surface protein by a Drosophila chemosensory protein induces behavioral defense against fungal parasitic infections

In addition to innate immunity in a physiological context, insects have evolved behavioral defenses against parasite attacks. Here, we report that Drosophila can sense the CFEM (common in fungal extracellular membrane) protein Mcdc9, which acts as a negative virulence factor of the entomopathogenic fungus Metarhizium robertsii. The individual deletions of 18 CFEM genes in Metarhizium followed by fly infection identified three null mutants that could kill the flies more quickly than the wild-type strain, among which Mcdc9 can coat fungal spores and interact with the fly chemosensory protein CheA75a. The deletion of Mcdc9 in the fungus or the knockdown of CheA75a in flies had a similar effect, in which a greater number of fungal spores were left on flies than on the respective controls after topical infection. Thus, similar to the accelerated death of the wild-type flies treated with ΔMcdc9, the CheA75aRNAi flies succumbed more quickly than the control insects topically challenged with the wild-type strain. The CheA75a gene is highly transcribed in fly legs and wings, and positive electrophysiological responses were evidenced in tarsal sensilla after stimulation with the Mcdc9 protein. The results imply that this CFEM protein could be sensed as a contact elicitor inducing the hygienic behavior of flies against fungal parasitic infection, which reveals a previously unsuspected mechanism of fungus-insect interactions.

Coupling cell proliferation rates to the duration of recruitment controls final size of the Drosophila wing.

Organ growth driven by cell proliferation is an exponential process. As a result, even small variations in proliferation rates, when integrated over a relatively long developmental time, will lead to large differences in size. How organs robustly control their final size despite perturbations in cell proliferation rates throughout development is a long-standing question in biology. Using a mathematical model, we show that in the developing wing of the fruit fly, Drosophila melanogaster, variations in proliferation rates of wing-committed cells are inversely proportional to the duration of cell recruitment, a differentiation process in which a population of undifferentiated cells adopt the wing fate by expressing the selector gene, vestigial. A time-course experiment shows that vestigial-expressing cells increase exponentially while recruitment takes place, but slows down when recruitable cells start to vanish, suggesting that undifferentiated cells may be driving proliferation of wing-committed cells. When this observation is incorporated in our model, we show that the duration of cell recruitment robustly determines a final wing size even when cell proliferation rates of wing-committed cells are perturbed. Finally, we show that this control mechanism fails when perturbations in proliferation rates affect both wing-committed and recruitable cells, providing an experimentally testable hypothesis of our model.

Preprint Highlight: Dynamic interplay of protrusive microtubule and contractile actomyosin forces drive tissue extension.

Cytoskeletal mechanical forces shape tissues during development. Although the role of the actomyosin machinery is extensively studied, how microtubules actively generate forces to shape tissues remains unknown. Combining in vivo experiments and simulations, this study elucidates that initial cell elongation during fly wing development is not driven by myosin contractility or external forces. Instead, protrusive forces generated by planar polarized noncentrosomal microtubules actively drive cell elongation, while myosin contractility is needed for final cell shape refinement. Thus ordered coordination between microtubules and actomyosin shapes the fly wing. This study will appeal to the broad cell and developmental biology community as it strengthens the growing notion that microtubules are active morphogenetic effectors. Beyond their core functions in cell division and intracellular transport, microtubule-mediated forces can directly dictate cell and tissue shape during development.

Live Imaging of Mitochondria in the Intact Fly Wing.

Detailed mechanisms governing the transport of mitochondria in neurons have recently emerged, although it is still poorly understood how the regulation of transport is coordinated in space and time within the physiological context of an organism. Here, we provide a protocol to study the intracellular dynamics of mitochondria in the wing neurons of adult Drosophila in situ. The mounting and imaging procedures that we describe are suitable for use on most microscopes, and they can be easily implemented in any laboratory. Our noninvasive mounting procedures, combined with the translucency of the wing cuticle in adult animals, makes the wing nervous system accessible to advanced microscopy studies in a physiological environment. Combining the powerful genetics of Drosophila with time-lapse live imaging, users of this protocol will be able to analyze mitochondrial dynamics over time in a subset of sensory neurons in the wing. These cells extend long axons with a stereotypical plus-end-out microtubule orientation that represents a unique model to understand the logic of neuronal cargo transport, including the mitochondria. Finally, the neurons in this tissue respond to mechanical and chemical stimulation of the sensory organs of the wing, opening up the possibility of coupling the study of mitochondrial dynamics with the modulation of neuronal activity in aging Drosophila We anticipate that the unique characteristics of this in vivo system will contribute to the discovery of novel mechanisms that regulate mitochondrial dynamics within an organismal context with relevant implications for the pathogenesis of age-dependent neurological disorders.

Clonal Imaging of Mitochondria in the Dissected Fly Wing.

Mitochondria are essential for long-term neuronal function and survival. They are maintained in neurons, including long axonal stretches, through dynamic processes such as fission, fusion, biogenesis, and mitophagy. Here, we describe a protocol for the in-depth morphological analysis of individual mitochondria in axons in vivo. Most mitochondrial analysis of axons is currently performed in vitro with neurons in a developmental state. Therefore, an understanding of the axonal mitochondrial network during aging in fully differentiated neurons and the long-term consequence of gene knockout is often not developed. By using a clonal system paired with fluorescent genetically encoded markers in the Drosophila wing, we can visualize individual neurons (out of the whole bundle), including their long axons and the mitochondria that they contain, using confocal imaging. The clonal system also allows visualization of neurons with genetic perturbations that would otherwise be lethal if present in the whole organism, allowing investigators to bypass lethality. This protocol can further be adapted to measure the physiological and biochemical state of the mitochondria. Mitochondrial morphology and health in axons are tightly linked to aging, axon injury, and neurodegeneration; therefore, this method can be used to investigate mitochondrial dysfunction associated with novel genes or those linked to neurodegenerative disease and axonopathy.

A method to predict the response to directional selection using a Kalman filter

Predicting evolution remains challenging. The field of quantitative genetics provides predictions for the response to directional selection through the breeder's equation, but these predictions can have errors. The sources of these errors include omission of traits under selection, inaccurate estimates of genetic variance, and nonlinearities in the relationship between genetic and phenotypic variation. Previous research showed that the expected value of these prediction errors is often not zero, so predictions are systematically biased. Here, we propose that this bias, rather than being a nuisance, can be used to improve the predictions. We use this to develop a method to predict evolution, which is built on three key innovations. First, the method predicts change as the breeder's equation plus a bias term. Second, the method combines information from the breeder's equation and from the record of past changes in the mean to predict change using a Kalman filter. Third, the parameters of the filter are fitted in each generation using a learning algorithm on the record of past changes. We compare the method to the breeder's equation in two artificial selection experiments, one using the wing of the fruit fly and another using simulations that include a complex mapping of genotypes to phenotypes. The proposed method outperforms the breeder's equation, particularly when traits under selection are omitted from the analysis, when data are noisy, and when additive genetic variance is estimated inaccurately or not estimated at all. The proposed method is easy to apply, requiring only the trait means over past generations.

A role for Flower and cell death in controlling morphogen gradient scaling.

During development, morphogen gradients encode positional information to pattern morphological structures during organogenesis1. Some gradients, like that of Dpp in the fly wing, remain proportional to the size of growing organs-that is, they scale. Gradient scaling keeps morphological patterns proportioned in organs of different sizes2,3. Here we show a mechanism of scaling that ensures that, when the gradient is smaller than the organ, cell death trims the developing tissue to match the size of the gradient. Scaling is controlled by molecular associations between Dally and Pentagone, known factors involved in scaling, and a key factor that mediates cell death, Flower4-6. We show that Flower activity in gradient expansion is not dominated by cell death, but by the activity of Dally/Pentagone on scaling. Here we show a potential connection between scaling and cell death that may uncover a molecular toolbox hijacked by tumours.