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Drosophila suzukii is an invasive pest of berries and other soft-skinned fruits, was first detected in Chile in 2017, and has since spread over 2,800 km from north to south. Sustainable control of the spotted-wing drosophila (SWD) is essential due the negative attitude of the consumers toward the excessive use of insecticides. During a survey in Chile for biological control agents, thirty-two isolates of entomopathogenic fungi (EPF) were isolated from mycotized insects and soil samples, identified through sequence analysis, and tested against D. suzukii adults under laboratory conditions. The EPF identified are Akanthomyces muscarius, Beauveria bassiana, Beauveria pseudobassiana, Clonostachys rosea, Metarhizium alvesii, Metarhizium brunneum and Metarhizium robertsii. Six isolates caused 100 % of mortality of D. suzukii adults within ten days after the initial exposition to conidia; these included four B. bassiana isolates (LSB 110, LSB 114, LSB 122 and LSB 125), one M. robertsii isolate (LSB 115) and one M. brunneum isolate (LSB 127). LSB 122 and LSB 125 induced the shortest lethal time (LT 50 4 and 4.2 days, respectively), while Akanthomyces and Clonostachys caused ≤ 36 % cumulative mortality of the adults at 10 days of exposure. These results indicate that isolates of B. bassiana, M. robertsii and M. brunneum have significant potential as microbial control agents against D. suzukii adults. This study marks a critical step forward in identifying and validating native entomopathogenic fungi in Chile for sustainable pest management. Future work will focus on further testing these isolates under laboratory, semi-field and field conditions to optimize their application in real-world agricultural settings., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

The vinegar fly Drosophila melanogaster is a pivotal model for invertebrate development, genetics, physiology, neuroscience, and disease. The whole family Drosophilidae, which contains over 4,400 species, offers a plethora of cases for comparative and evolutionary studies. Despite a long history of phylogenetic inference, many relationships remain unresolved among the genera, subgenera, and species groups in the Drosophilidae. To clarify these relationships, we first developed a set of new genomic markers and assembled a multilocus data set of 17 genes from 704 species of Drosophilidae. We then inferred a species tree with highly supported groups for this family. Additionally, we were able to determine the phylogenetic position of some previously unplaced species. These results establish a new framework for investigating the evolution of traits in fruit flies, as well as valuable resources for systematics., (© The Author(s) 2021. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.)

Background: The most species-rich radiation of animal life in the 66 million years following the Cretaceous extinction event is that of schizophoran flies: a third of fly diversity including Drosophila fruit fly model organisms, house flies, forensic blow flies, agricultural pest flies, and many other well and poorly known true flies. Rapid diversification has hindered previous attempts to elucidate the phylogenetic relationships among major schizophoran clades. A robust phylogenetic hypothesis for the major lineages containing these 55,000 described species would be critical to understand the processes that contributed to the diversity of these flies. We use protein encoding sequence data from transcriptomes, including 3145 genes from 70 species, representing all superfamilies, to improve the resolution of this previously intractable phylogenetic challenge., Results: Our results support a paraphyletic acalyptrate grade including a monophyletic Calyptratae and the monophyly of half of the acalyptrate superfamilies. The primary branching framework of Schizophora is well supported for the first time, revealing the primarily parasitic Pipunculidae and Sciomyzoidea stat. rev. as successive sister groups to the remaining Schizophora. Ephydroidea, Drosophila's superfamily, is the sister group of Calyptratae. Sphaeroceroidea has modest support as the sister to all non-sciomyzoid Schizophora. We define two novel lineages corroborated by morphological traits, the 'Modified Oviscapt Clade' containing Tephritoidea, Nerioidea, and other families, and the 'Cleft Pedicel Clade' containing Calyptratae, Ephydroidea, and other families. Support values remain low among a challenging subset of lineages, including Diopsidae. The placement of these families remained uncertain in both concatenated maximum likelihood and multispecies coalescent approaches. Rogue taxon removal was effective in increasing support values compared with strategies that maximise gene coverage or minimise missing data., Conclusions: Dividing most acalyptrate fly groups into four major lineages is supported consistently across analyses. Understanding the fundamental branching patterns of schizophoran flies provides a foundation for future comparative research on the genetics, ecology, and biocontrol.

Drosophila suzukii (Matsumura) (Diptera: Drosophilidae) is a damaging pest of fruit. Reproductively diapausing adults overwinter in woodlands and remain active on warmer winter days. It is unknown if this adult phase of the lifecycle feeds during the winter period, and what the food source may be. This study characterized the flora in the digestive tract of D. suzukii using a metagenomics approach. Live D. suzukii were trapped in four woodlands in the south of England and their guts dissected for DNA extraction and amplicon-based metagenomics sequencing (internal transcribed spacer and 16S rRNA). Analysis at genus and family taxonomic levels showed high levels of diversity with no differences in digestive tract bacterial or fungal biota between woodland sites of winter-form D. suzukii. Female D. suzukii at one site appeared to have higher bacterial diversity in the alimentary canal than males, but there was a site, sex interaction. Many of the biota were associated with cold, wet climatic conditions and decomposition. This study provides the first evidence that winter-form D. suzukii may be opportunistic feeders during the winter period and are probably exploiting food sources associated with moisture on decomposing vegetation during this time. A core gut microbiome has been identified for winter-form D. suzukii., (© 2018 The Royal Entomological Society.)

Chemosensory perception allows insects to interact with the environment by perceiving odorant or tastant molecules; genes encoding chemoreceptors are the molecular interface between the environment and the insect, and play a central role in mediating its chemosensory behavior. Here, we explore how the evolution of these genes in the emerging pest Drosophila suzukii correlates with the peculiar ecology of this species. We annotated approximately 130 genes coding for gustatory receptors (GRs) and divergent ionotropic receptors (dIRs) in D. suzukii and in its close relative D. biarmipes We then analyzed the evolution, in terms of size, of each gene family as well of the molecular evolution of the genes in a 14 Drosophila species phylogenetic framework. We show that the overall evolution of GRs parallels that of dIRs not only in D. suzukii, but also in all other analyzed Drosophila Our results reveal an unprecedented burst of gene family size in the lineage leading to the suzukii subgroup, as well as genomic changes that characterize D. suzukii, particularly duplications and strong signs of positive selection in the putative bitter-taste receptor GR59d. Expression studies of duplicate genes in D. suzukii support a spatio-temporal subfunctionalization of the duplicate isoforms. Our results suggest that D. suzukii is not characterized by gene loss, as observed in other specialist Drosophila species, but rather by a dramatic acceleration of gene gains, compatible with a highly generalist feeding behavior. Overall, our analyses provide candidate taste receptors specific for D. suzukii that may correlate with its specific behavior, and which may be tested in functional studies to ultimately enhance its control in the field., (Copyright © 2016 Crava et al.)

The complete mitochondrial genome of Leptopilina myrica Chen, 2023 has been sequenced and analyzed for the first time. The total length we assembled is 15,448 bp, which comprises 13 PCGs, 22 tRNAs, 2 rRNAs, and a CR. The overall nucleotide composition consists of 41.1% A, 37.7% T, 14.7% C, and 6.5% G, respectively. The nucleotide sequences of 13 PCGs and 2 rRNAs from L. myrica and another 10 Drosophila parasitoid species were used for phylogenetic analysis by MrBayes, with one species from Drosophilidae as an outgroup. The result shows that L. myrica is closely related to L. syphax. [ABSTRACT FROM AUTHOR]

Drosophilidae, a diverse and widespread fly family, has recently received increasing attention due to the proliferation of its agricultural pest species, especially in fruit-growing regions. This study aimed to assess the diversity of Drosophilidae in strawberry fields within the Konya province from April to December 2022. A total of 10 species belonging to 4 genera (Drosophila Fallén, Hirtodrosophila Duda, Zaprionus Coquillett, Phortica Schiner) were identified in the Drosophilidae family. This study reported the presence of Drosophila busckii Coquillett, Drosophila hydei (Sturtevant), Drosophila obscura (Fallén), Drosophila subobscura (Collin), Drosophila simulans (Sturtevant), Drosophila suzukii (Matsumura), Hirtodrosophila cameraria (Haliday), Phortica variegata (Fallén) and Zaprionus indianus (Gupta) in Konya (Türkiye) for the first time. Additionally, Drosophila obscura, Drosophila simulans, Hirtodrosophila cameraria and Phortica variegata were determined for the first time in Türkiye's strawberry fields. [ABSTRACT FROM AUTHOR]

In this study, the presence and prevalence of Drosophilidae species were studied in cherry and peach plantations of Tokat province in 2021-2022. In addition, the population of the species belonging to the family was monitored for two years in one peach and cherry plantations in central district of Tokat. According to the results, a total of 10 species were recorded. These species are Drosophila hydei Sturtevant, 1921, D. immigrans Sturtevant, 1921, D. melanogaster Meigen, 1830, D. phalerata Meigen, 1830, D. simulans Sturtevant, 1919, D. subobscura Collin, 1936, D. suzukii (Matsumura, 1931), Gitona distigma Meigen, 1830, Scaptomyza pallida (Zetterstedt, 1847), D. transversa Fallen, 1823. Of these, 10 species were determined in the central district of Tokat, 9 species in Erbaa, 8 species in Turhal and 6 species in Pazar. D. subobscura Collin, 1936 was the most common species in cherry and peach fields in central district of Tokat in 2021 and 2022. In Erbaa, D. subobscura was the most common species in cherry fields in 2021 and D. hydeii Sturtevant, 1921 and S. pallida (Zetterstedt, 1847) took the first place in terms of prevalence in peach fields. In 2022, the most common species in cherry and peach fields was D. subobscura in Erbaa. While D. hydei was the most common species in cherry and peach plantations in Turhal in 2021, D. immigrans Sturtevant, 1921 in cherry fields, and D. subobscura in peach fields were common in 2022. In the cherry fields in Pazar, the common species was D. immigrans in 2021 and D. subobscura in 2022. D. suzukii (Matsumura, 1931), one of the important species in the family, was recorded in cherry and peach plantations in central district of Tokat and Erbaa, and in peach plantations in Turhal. D. suzukii was seen for the first time on 25 Aug. (2 specimens) in the cherry fields of Tokat Centre in 2021, while it could not be detected in the peach fields. In 2022, the first adult detection in cherry areas was made on 29 Aug. (7 specimes) and in peach areas on 08 Aug. (1 specimen). This study is the first detailed study on Drosophilidae family in Tokat (Türkiye) province. [ABSTRACT FROM AUTHOR]

Drosophila glue, a bioadhesive produced by fly larvae to attach themselves to a substrate for several days, has recently gained attention for its peculiar adhesive and mechanical properties. Although Drosophila glue production was described more than 50 years ago, a general survey of the adhesive and mechanical properties of this proteinaceous gel across Drosophila species is lacking. To measure adhesion, we present here a protocol that is robust to variations in protocol parameters, pupal age and calculation methods. We find that the glue, which covers the entire pupal surface, increases the animal rigidity and plasticity when bound to a glass slide. Our survey of pupal adhesion in 25 Drosophilidae species reveals a wide range of phenotypes, from species that produce no or little glue and adhere little, to species that produce high amounts of glue and adhere strongly. One species, D. hydei, stands out from the rest and emerges as a promising model for the development of future bioadhesives, as it has the highest detachment force per glue area and produces relatively large amounts of glue relative to its size. We also observe that species that invest more in glue tend to live in more windy and less rainy climates, suggesting that differences in pupal adhesion properties across species are shaped by ecological factors. Our present survey provides a basis for future biomimetic studies based on Drosophila glue. [ABSTRACT FROM AUTHOR]

The conserved bazooka (baz/par3) gene acts as a key regulator of asymmetrical cell divisions across the animal kingdom. Associated Par3/Baz-Par6-aPKC protein complexes are also well known for their role in the establishment of apical/basal cell polarity in epithelial cells. Here we define a novel, positive function of Baz/Par3 in the Notch pathway. Using Drosophila wing and eye development, we demonstrate that Baz is required for Notch signaling activity and optimal transcriptional activation of Notch target genes. Baz appears to act independently of aPKC in these contexts, as knockdown of aPKC does not cause Notch loss-of-function phenotypes. Using transgenic Notch constructs, our data positions Baz activity downstream of activating Notch cleavage steps and upstream of Su(H)/CSL transcription factor complex activity on Notch target genes. We demonstrate a biochemical interaction between NICD and Baz, suggesting that Baz is required for NICD activity before NICD binds to Su(H). Taken together, our data define a novel role of the polarity protein Baz/Par3, as a positive and direct regulator of Notch signaling through its interaction with NICD. [Display omitted] • PAR3/Bazooka acts generally in Notch-signaling in Drosophila. • PAR3/Bazooka promotes Notch signaling outside the asymmetric division context. • Notch-ICD and PAR3/Bazooka can be associated in the same physical complex. • PAR3/Bazooka acts at the level of the cleaved active Notch-ICD protein fragment. [ABSTRACT FROM AUTHOR]

Ceratocystis fimbriata, the causal agent of sweetpotato black rot, is a pathogen capable of developing and spreading within postharvest settings. A survey of North Carolina sweetpotato storage facilities was conducted to determine the arthropods present and identify potential vectors of C. fimbriata. Sixteen taxonomic categories were recovered, and the genus Drosophila (Diptera: Drosophilidae) accounted for 79% of individuals sampled, with Drosophila hydei being the most abundant species. Behavioral assays were conducted to determine if D. hydei is attracted to C. fimbriata-inoculated roots and if the pathogen could be recovered from external or intornal surfaces of the insect. Flles were released in insect-trapping pitchers containing either C. fimbriata-inoculated or noninoculated roots or Petri dishes. No significant differences in fly number were detected in sweetpotato-baited pitchers; however, significant differences were found in the pitcher baited with a mature C. fimbriata culture. Flies were subjected to washes to determine if viable C. fimbriata was present (internally or externally); washes were plated onto carrot agar plates and observed for the presence of C. fimbriata colonies. Both external and internal washes had viable C. fimbriata inocula with no significant differences, and inoculated sweetpotatoes had a significantly higher number of flies carrying C. fimbriata. This study suggests that D. hydei can carry C. fimbriata from infected sweetpotatoes and move viable C. fimbriata inocula both externally and internally, making this the first report of any Drosophila sp. serving as a potential vector for the Ceratocystis genus. [ABSTRACT FROM AUTHOR]

In the natural world, animals make decisions on an ongoing basis, continuously selecting which action to undertake next. In the lab, however, the neural bases of decision processes have mostly been studied using artificial trial structures. New experimental tools based on the genetic toolkit of model organisms now make it experimentally feasible to monitor and manipulate neural activity in small subsets of neurons during naturalistic behaviors. We thus propose a new approach to investigating decision processes, termed reverse neuroethology. In this approach, experimenters select animal models based on experimental accessibility and then utilize cutting-edge tools such as connectomes and genetically encoded reagents to analyze the flow of information through an animal's nervous system during naturalistic choice behaviors. We describe how the reverse neuroethology strategy has been applied to understand the neural underpinnings of innate, rapid decision making, with a focus on defensive behavioral choices in the vinegar fly Drosophila melanogaster. [ABSTRACT FROM AUTHOR]

Invertebrates lack the immune machinery underlying vertebrate-like acquired immunity. However, in many insects past infection by the same pathogen can 'prime' the immune response, resulting in improved survival upon reinfection. Here, we investigated the mechanistic basis and epidemiological consequences of innate immune priming in the fruit fly Drosophila melanogaster when infected with the gram-negative bacterial pathogen Providencia rettgeri. We find that priming in response to P. rettgeri infection is long-lasting and sexually dimorphic response. We further explore the epidemiological consequences of immune priming and find it has the potential to curtail pathogen transmission by reducing pathogen shedding and spread. The enhanced survival of individuals previously exposed to a non-lethal bacterial inoculum coincided with a transient decrease in bacterial loads, and we provide strong evidence that the effect of priming requires the IMD-responsive antimicrobial-peptide Diptericin-B in the fat body. Further, we show that while Diptericin B is the main effector of bacterial clearance, it is not sufficient for immune priming, which requires regulation of IMD by peptidoglycan recognition proteins. This work underscores the plasticity and complexity of invertebrate responses to infection, providing novel experimental evidence for the effects of innate immune priming on population-level epidemiological outcomes. Author summary: When we are vaccinated, our immune response is able to respond quickly if we are ever exposed to the same pathogen in the future. Unlike humans, the immune systems of invertebrates, such as insects, are not capable of the same type of specific immune memory. However, much work has shown that insects previously exposed to an inactivated pathogen will fare better if they are re-infected–a phenomenon broadly called "immune priming". How insects are able to do this is an exciting focus of current research. We investigated immune priming in the fruit fly, a powerful model system for infection and immunity. We found that exposure to an inactivated form of the bacterial fly pathogen Providencia rettgeri resulted in flies surviving a subsequent live infection. This effect lasted several days, was stronger in male flies, and was seen in different fly genetic backgrounds. We uncovered that priming requires a specific immune response in the fly fat-body (the equivalent to a fly 'liver') that produces an antimicrobial protein called Diptericin. We also found that primed flies were able to keep pathogen growth lower, and that this reduced their ability to spread the infection to other flies. [ABSTRACT FROM AUTHOR]

The last decade has been highlighted by the increased use of next-generation DNA sequencing technology to identify novel human disease genes. A critical downstream part of this process is assigning function to a candidate gene variant. Functional studies in Drosophila melanogaster, the common fruit fly, have made a prominent contribution in annotating variant impact in an in vivo system. The use of patient-derived knock-in flies or rescue-based, "humanization", approaches are novel and valuable strategies in variant testing but have been recently widely reviewed. An often-overlooked strategy for determining variant impact has been GAL4/upstream activation sequence-mediated tissue-defined overexpression in Drosophila. This mini-review will summarize the recent contribution of ectopic overexpression of human reference and variant cDNA in Drosophila to assess variant function, interpret the consequence of the variant, and in some cases infer biological mechanisms. [ABSTRACT FROM AUTHOR]

Drosophila nervous system development progresses through a series of well-characterized steps in which homeodomain transcription factors (HDTFs) play key roles during most, if not all, phases. Strikingly, although some HDTFs have only one role, many others are involved in multiple steps of the developmental process. Most Drosophila HDTFs engaged in nervous system development are conserved in vertebrates and often play similar roles during vertebrate development. In this Spotlight, we focus on the role of HDTFs during embryogenesis, where they were first characterized. [ABSTRACT FROM AUTHOR]

Drosophila remains a pre-eminent insect model system for host–virus interaction, but the host range and fitness consequences of the drosophilid virome are poorly understood. Metagenomic studies have reported approximately 200 viruses associated with Drosophilidae, but few isolates are available to characterize the Drosophila immune response, and most characterization has relied on injection and systemic infection. Here, we use a more natural infection route to characterize the fitness effects of infection and to study a wider range of viruses. We exposed laboratory Drosophila melanogaster to 23 naturally occurring viruses from wild-collected drosophilids. We recorded transmission rates along with two components of female fitness: survival and the lifetime number of adult offspring produced. Nine different viruses transmitted during contact with laboratory D. melanogaster, although for the majority, rates of transmission were less than 20%. Five virus infections led to a significant decrease in lifespan (D. melanogaster Nora virus, D. immigrans Nora virus, Muthill virus, galbut virus and Prestney Burn virus), and three led to a reduction in the total number of offspring. Our findings demonstrate the utility of the Drosophila model for community-level studies of host–virus interactions, and suggest that viral infection could be a substantial fitness burden on wild flies. [ABSTRACT FROM AUTHOR]

Flies in the Drosophila (Sophophora) obscura species group are among the most common native drosophilids in northern temperate and boreal forests; southward, into cool, montane tropical forests they are rare and localized, but diverse. Of the world's 48 species, 18 occur in the New World, including three new neotropical species described here. Here, all New World species are diagnosed, many with images and the use of some new morphological features such as female terminalia (oviscapt and spermathecal structure). A basic phylogenetic scheme of relationships based on 19 morphological characters corresponds well with molecular trees. Type series have been rediscovered of D. algonquin, athabasca, azteca, narragansett, and seminole (all described by Sturtevant and Dobzhansky in 1936), from which a lectotype is designated for each of the first four species and the holotype is recognized for seminole. Drosophila narragansett from the eastern United States, which has been found only once in 60 years, is redescribed in detail from historical material; D. seminole is found to be a synonym of narragansett. The three new species are Drosophila chibcha, n. sp. (from Costa Rica to Venezuela and Peru), D. olmeca, n. sp. (from southern Mexico), both of these in the a nis subgroup; and D. zapoteca, n. sp. (from Guatemala), in the pseudoobscura subgroup. Signifficant new distributional and host records are reported for various species. [ABSTRACT FROM AUTHOR]

Adenine phosphoribosyltransferase (APRT) and hypoxanthine-guanine phosphoribosyltransferase (HGPRT) are two structurally related enzymes involved in purine recycling in humans. Inherited mutations that suppress HGPRT activity are associated with Lesch-Nyhan disease (LND), a rare X-linked metabolic and neurological disorder in children, characterized by hyperuricemia, dystonia, and compulsive self-injury. To date, no treatment is available for these neurological defects and no animal model recapitulates all symptoms of LND patients. Here, we studied LND-related mechanisms in the fruit fly. By combining enzymatic assays and phylogenetic analysis, we confirm that no HGPRT activity is expressed in Drosophila melanogaster, making the APRT homolog (Aprt) the only purine-recycling enzyme in this organism. Whereas APRT deficiency does not trigger neurological defects in humans, we observed that Drosophila Aprt mutants show both metabolic and neurobehavioral disturbances, including increased uric acid levels, locomotor impairments, sleep alterations, seizure-like behavior, reduced lifespan, and reduction of adenosine signaling and content. Locomotor defects could be rescued by Aprt re-expression in neurons and reproduced by knocking down Aprt selectively in the protocerebral anterior medial (PAM) dopaminergic neurons, the mushroom bodies, or glia subsets. Ingestion of allopurinol rescued uric acid levels in Aprt-deficient mutants but not neurological defects, as is the case in LND patients, while feeding adenosine or N6-methyladenosine (m6A) during development fully rescued the epileptic behavior. Intriguingly, pan-neuronal expression of an LND-associated mutant form of human HGPRT (I42T), but not the wild-type enzyme, resulted in early locomotor defects and seizure in flies, similar to Aprt deficiency. Overall, our results suggest that Drosophila could be used in different ways to better understand LND and seek a cure for this dramatic disease. [ABSTRACT FROM AUTHOR]

The spotted wing drosophila (SWD), Drosophila suzukii Matsumura (Diptera: Drosophilidae), is considered a significant invasive polyphagus pest of soft-skinned fruit, including raspberries, strawberries, blackberries, figs, blueberries and cherries. Apart from ripening fruits, D. suzukii females lay eggs in numerous wild fruits as well. In the Republic of Serbia, it was detected for the first time during October and November 2014, where it endangers the production of raspberries, one of the most important fruits for the country. Considering a high reproductive rate and short generation time, easy and fast-spreading due to global trade, and a suitable climate with the presence of host plants year-round contribute towards making this pest a serious threat to the reduction of quality and yield of growing fruit. Current control efforts rely mostly on the use of chemical insecticides. In addition to insecticides, sanitary measures and mechanical control are used to control this pest, which is an indispensable and important stage in safe fruit growing. This article provides an overview of the impact of D. suzukii on fruit production and establishes available measures and strategies for its control in the Republic of Serbia. [ABSTRACT FROM AUTHOR]

CO2 anesthesia is the most common method for immobilizing Drosophila for research purposes. But CO2 exposure has consequences—it can impact fertility, behavior, morphogenesis, and cytoskeletal dynamics. In this respect, Drosophila is an outstanding model for studying the impact of CO2 exposure on tissues. In this study we explored the response of intracellular pH (pHi) to a one-minute CO2 pulse using a genetically encoded, ubiquitously expressed pH sensor, tpHusion, to monitor pHi within a live, intact, whole fly. We compared wild-type flies to flies lacking Imaginal disc growth factors (Idgfs), which are chitinase-like proteins that facilitate developmental processes and the innate immune response. Morphogenetic and cytoskeletal defects in Idgf-null flies are enhanced after CO2 exposure. We found that pHi drops sharply within seconds of the beginning of a CO2 pulse and recovers over several minutes. The initial profile was nearly identical in control and Idgf-null flies but diverged as the pHi returned to normal. This study demonstrates the feasibility of monitoring pH in live adult Drosophila. Studies exploring pH homeostasis are important for understanding human pathologies associated with pH dysregulation. [ABSTRACT FROM AUTHOR]

Lifespan is a complex quantitative trait involving genetic and non-genetic factors as well as the peculiarities of ontogenesis. As with all quantitative traits, lifespan shows considerable variation within populations and between individuals. Drosophila, a favourite object of geneticists, has greatly advanced our understanding of how different forms of variability affect lifespan. This review considers the role of heritable genetic variability, phenotypic plasticity and stochastic variability in controlling lifespan in Drosophila melanogaster. We discuss the major historical milestones in the development of the genetic approach to study lifespan, the breeding of long-lived lines, advances in lifespan QTL mapping, the environmental factors that have the greatest influence on lifespan in laboratory maintained flies, and the mechanisms, by which individual development affects longevity. The interplay between approaches to study ageing and lifespan limitation will also be discussed. Particular attention will be paid to the interaction of different types of variability in the control of lifespan. [ABSTRACT FROM AUTHOR]

Neurofibromatosis 1 (NF1) is a multisymptomatic disorder with highly variable presentations, which include short stature, susceptibility to formation of the characteristic benign tumors known as neurofibromas, intense freckling and skin discoloration, and cognitive deficits, which characterize most children with the condition. Attention deficits and Autism Spectrum manifestations augment the compromised learning presented by most patients, leading to behavioral problems and school failure, while fragmented sleep contributes to chronic fatigue and poor quality of life. Neurofibromin (Nf1) is present ubiquitously during human development and postnatally in most neuronal, oligodendrocyte, and Schwann cells. Evidence largely from animal models including Drosophila suggests that the symptomatic variability may reflect distinct cell-type-specific functions of the protein, which emerge upon its loss, or mutations affecting the different functional domains of the protein. This review summarizes the contributions of Drosophila in modeling multiple NF1 manifestations, addressing hypotheses regarding the cell-type-specific functions of the protein and exploring the molecular pathways affected upon loss of the highly conserved fly homolog dNf1. Collectively, work in this model not only has efficiently and expediently modelled multiple aspects of the condition and increased understanding of its behavioral manifestations, but also has led to pharmaceutical strategies towards their amelioration. [ABSTRACT FROM AUTHOR]

Introduction: Endosymbiotic Wolbachia bacteria are widespread in nature, present in half of all insect species. The success of Wolbachia is supported by a commensal lifestyle. Unlike bacterial pathogens that overreplicate and harm host cells, Wolbachia infections have a relatively innocuous intracellular lifestyle. This raises important questions about how Wolbachia infection is regulated. Little is known about how Wolbachia abundance is controlled at an organismal scale. Methods: This study demonstrates methodology for rigorous identification of cellular processes that affect whole-body Wolbachia abundance, as indicated by absolute counts of the Wolbachia surface protein (wsp) gene. Results: Candidate pathways, associated with well-described infection scenarios, were identified. Wolbachia-infected fruit flies were exposed to small molecule inhibitors known for targeting those same pathways. Sequential tests in D. melanogaster and D. simulans yielded a subset of chemical inhibitors that significantly affected whole-body Wolbachia abundance, including the Wnt pathway disruptor, IWR-1 and the mTOR pathway inhibitor, Rapamycin. The implicated pathways were genetically retested for effects in D. melanogaster, using inducible RNAi expression driven by constitutive as well as chemically-induced somatic GAL4 expression. Genetic disruptions of armadillo, tor, and ATG6 significantly affected whole-body Wolbachia abundance. Discussion: As such, the data corroborate reagent targeting and pathway relevance to whole-body Wolbachia infection. The results also implicate Wnt and mTOR regulation of autophagy as important for regulation of Wolbachia titer. [ABSTRACT FROM AUTHOR]

Sexual dimorphism in traits of insects during the developmental stages could potentially be the direct or indirect result of sex-specific selection provided that genetic variation for sexual dimorphism is present. We investigated genetic variation in sexual dimorphism in a set of Drosophila melanogaster inbred lines for 2 traits: egg to adult development time and pupation site preference. We observed considerable genetic variation in sexual dimorphism among lines in both traits. The sexual dimorphic patterns remained relatively consistent across multiple trials, despite both traits being sensitive to environmental conditions. Additionally, we measured 2 sexually dimorphic adult morphological traits in 6 sampled lines and investigated correlations in the sexual dimorphism patterns with the 2 developmental traits. The abundance of genetic variation in sexual dimorphism for D. melanogaster developmental traits demonstrated in this study provides evidence for a high degree of evolvability of sex differences in preadult traits in natural populations. [ABSTRACT FROM AUTHOR]

The susceptibility of insects to rising temperatures has largely been measured by their ability to survive thermal extremes. However, the capacity for maternally inherited endosymbionts to influence insect heat tolerance has been overlooked. Further, while some studies have addressed the impact of heat on traits like fertility, which can decline at temperatures below lethal thermal limits, none have considered the impact of endosymbionts. Here, we assess the impact of three Wolbachia strains (wRi, wAu and wNo) on the survival and fertility of Drosophila simulans exposed to heat stress during development or as adults. The effect of Wolbachia infection on heat tolerance was generally small and trait/strain specific. Only the wNo infection significantly reduced the survival of adult males after a heat shock. When exposed to fluctuating heat stress during development, the wRi and wAu strains reduced egg‐to‐adult survival but only the wNo infection reduced male fertility. Wolbachia densities of all three strains decreased under developmental heat stress, but reductions occurred at temperatures above those that reduced host fertility. These findings emphasize the necessity to account for endosymbionts and their effect on both survival and fertility when investigating insect responses to heat stress. [ABSTRACT FROM AUTHOR]

Insect exocrine gland products can be involved in sexual communication, defense, territory labelling, aggregation and alarm. In the vinegar fly Drosophila melanogaster the ejaculatory bulb synthesizes and releases 11-cis-Vaccenyl acetate (cVa). This pheromone, transferred to the female during copulation, affects aggregation, courtship and male-male aggressive behaviors. To determine the ability of male flies to replenish their cVa levels, males of a control laboratory strain and from the desat1 pheromone-defective mutant strain were allowed to mate successively with several females. We measured mating frequency, duration and latency, the amount of cVa transferred to mated females and the residual cVa in tested males. Mating duration remained constant with multiple matings, but we found that the amount of cVa transferred to females declined with multiple matings, indicating that, over short, biologically-relevant periods, replenishment of the pheromone does not keep up with mating frequency, resulting in the transfer of varying quantities of cVa. Adult responses to cVa are affected by early developmental exposure to this pheromone; our revelation of quantitative variation in the amount of cVa transferred to females in the event of multiple matings by a male suggests variable responses to cVa shown by adults produced by such matings. This implies that the natural role of this compound may be richer than suggested by laboratory experiments that study only one mating event and its immediate behavioral or neurobiological consequences. [ABSTRACT FROM AUTHOR]

Structural matching of genitalia between sexes of the same species would guarantee a stable mating posture and tight genital coupling that minimizes the reproductive cost in females. Interspecific mating might cause mismatches in genital structures between sexes, leading to an unstable mating posture, abnormal genital coupling, enhanced risk of wounding to the genitalia, and reduced mating duration. In this study, copulation duration, mating posture, genital coupling and copulatory wounding were analysed in reciprocal combinations of interspecific mating between Drosophila auraria and Drosophila triauraria and between Drosophila biauraria and Drosophila subauraria. Interspecific mating exhibited a large variation in copulation duration, and copulatory wounds were produced in females at positions that lacked the corresponding fold structures, although the frequency of copulatory wounds was sometimes lower than in intraspecific mating. The angle of the aedeagus insertion during mating and positions of the copulatory wounds after interspecific mating were as expected from the male species, suggesting that males attempt to tighten genital coupling and stabilize copulation using the genitalia regardless of the female species. As in other groups of Drosophila studied to date, the species-specific structures in female genitalia contact the conspecific male organs during copulation, and the results suggest that they might have functions related to sexual conflict or sexual selection. [ABSTRACT FROM AUTHOR]

Herbivorous insects and their host plants comprise most known species on Earth. Illuminating how herbivory repeatedly evolved in insects from nonherbivorous lineages is critical to understanding how this biodiversity is created and maintained. We characterized the trophic niche of Scaptomyza flava, a representative of a lineage nested within the Drosophila that transitioned to herbivory ~10–15 million years ago. We used natural history studies to determine whether S. flava is a true herbivore or a cryptic microbe‐feeder, given that the ancestral character state for the family Drosophilidae is likely microbe‐feeding. Specifically, we quantified oviposition substrate choice and larval viability across food types, trophic‐related morphological traits, and nitrogen isotope and sterol profiles across putatively herbivorous and nonherbivorous drosophilids. The results of these studies show that S. flava is an obligate herbivore of living plants. Paired with its genetic model host, Arabidopsis thaliana, S. flava is a novel and powerful system for exploring mechanisms underlying the evolution of herbivory, a complex trait that enabled the exceptional diversification of insects. [ABSTRACT FROM AUTHOR]

Microplastics (MPs) have become a prominent environmental concern due to their ubiquity in various ecosystems and widespread distribution through multiple channels. In this study, the oral effects of 2,000 mesh polytetrafluoroethylene (PTFE) microplastics were tested against Drosophila melanogaster (Meigen), at concentrations of 0, 0.1, 1, 10, and 20. After exposure to a microplastic-containing medium for 20 days, energy metabolism, fecundity, spontaneous movement, and sleeping time were measured. The study results showed that glucose levels in male flies were significantly reduced after exposure to PTFE-MPs. Measurement of lipid and protein levels indicated an increase in males but decrease in females, whereas these changes were not statistically significant. Reduction in sleep time was also observed, especially in males at the concentration of 20 g/l. Our study indicates that chronic exposure of PTFE-MPs can change energy metabolism and the amount of sleep on D. melanogaster in a sex dependent and dose dependent way. The results of our study are hoped to contribute to a better understanding of the effects of microplastics as new pollutants on insects. [ABSTRACT FROM AUTHOR]

The Drosophila repleta group is one of the most widely used model systems for studying adaptation and speciation. Traditionally, five subgroups are recognized within the repleta group: fasciola, hydei, mercatorum, repleta and mulleri. A sixth subgroup, inca, was the last to be defined. The inca species subgroup includes three species: Drosophila inca, Drosophila huancavilcae and Drosophila yangana, all of which are endemic to Ecuador and Peru. Previous molecular phylogenetic studies have been inconclusive regarding the geographic location, time and mode of diversification of lineages within the repleta group. By applying a phylogenetic and biogeographical analysis of 54 taxa belonging to the repleta, nannoptera, atalaia and virilis groups, the aim of this study was to: (1) determine the relationships between the inca subgroup and the other five subgroups within the repleta group, (2) improve the unresolved branching and low supports of the early divergent lineages in the repleta group phylogeny and (3) estimate the geographic and temporal context of the early divergence within the repleta group. Based on these findings, it is proposed that the Drosophila repleta group first diversified during the mid-late Miocene, most likely following the uplift of the Northwestern Andes. [ABSTRACT FROM AUTHOR]

Odysseus (OdsH) was the first speciation gene described in Drosophila related to hybrid sterility in offspring of mating between Drosophila mauritiana and Drosophila simulans. Its origin is attributed to the duplication of the gene unc-4 in the subgenus Sophophora. By using a much larger sample of Drosophilidae species, we showed that contrary to what has been previously proposed, OdsH origin occurred 62 MYA. Evolutionary rates, expression, and transcription factor–binding sites of OdsH evidence that it may have rapidly experienced neofunctionalization in male sexual functions. Furthermore, the analysis of the OdsH peptide allowed the identification of mutations of D. mauritiana that could result in incompatibility in hybrids. In order to find if OdsH could be related to hybrid sterility, beyond Sophophora , we explored the expression of OdsH in Drosophila arizonae and Drosophila mojavensis , a pair of sister species with incomplete reproductive isolation. Our data indicated that OdsH expression is not atypical in their male-sterile hybrids. In conclusion, we have proposed that the origin of OdsH occurred earlier than previously proposed, followed by neofunctionalization. Our results also suggested that its role as a speciation gene might be restricted to D. mauritiana and D. simulans. [ABSTRACT FROM AUTHOR]

Prezygotic isolation is often stronger between sympatric as opposed to allopatric taxa, but the underlying cause can be difficult to infer from comparative studies alone. Experimental evolution, where evolutionary responses to treatments manipulating the presence/absence of heterospecific individuals are tracked, can provide a powerful complementary approach. We used experimental evolution to investigate a naturally occurring pattern of reproductive character displacement in the mushroom-feeding fly, Drosophila subquinaria. In nature, female D. subquinaria from populations sympatric with the closely related Drosophila recens discriminate more strongly against heterospecific males than do females from allopatric populations. Starting with 16 replicate allopatric populations of D. subquinaria , we manipulated the presence/absence of D. recens during mating (experimental sympatry vs. control) and, when present, we allowed hybrids to live or kill them each generation. Across 12 generations, heterospecific offspring production from no-choice mating trials between D. subquinaria females and D. recens males declined in both experimental sympatry treatments relative to the control, suggesting increased sexual isolation. Male cuticular hydrocarbon profiles also evolved, but only in the hybrids killed treatment. Our results strongly imply that the existing reproductive character displacement in wild D. subquinaria populations was an evolutionary response to selection arising from secondary contact with D. recens. [ABSTRACT FROM AUTHOR]

Johnston's organ, the Drosophila auditory organ, is anatomically very different from the mammalian organ of Corti. However, recent evidence indicates significant cellular and molecular similarities exist between vertebrate and invertebrate hearing, suggesting that Drosophila may be a useful platform to determine the function of the many mammalian deafness genes whose underlying biological mechanisms are poorly characterized. Our goal was a comprehensive screen of all known orthologues of mammalian deafness genes in the fruit fly to better understand conservation of hearing mechanisms between the insect and the fly and ultimately gain insight into human hereditary deafness. We used bioinformatic comparisons to screen previously reported human and mouse deafness genes and found that 156 of them have orthologues in Drosophila melanogaster. We used fluorescent imaging of T2A-GAL4 gene trap and GFP or YFP fluorescent protein trap lines for 54 of the Drosophila genes and found 38 to be expressed in different cell types in Johnston's organ. We phenotypically characterized the function of strong loss-of-function mutants in three genes expressed in Johnston's organ (Cad99C, Msp-300, and Koi) using a courtship assay and electrophysiological recordings of sound-evoked potentials. Cad99C and Koi were found to have significant courtship defects. However, when we tested these genes for electrophysiological defects in hearing response, we did not see a significant difference suggesting the courtship defects were not caused by hearing deficiencies. Furthermore, we used a UAS/RNAi approach to test the function of seven genes and found two additional genes, CG5921 and Myo10a, that gave a statistically significant delay in courtship but not in sound-evoked potentials. Our results suggest that many mammalian deafness genes have Drosophila homologues expressed in the Johnston's organ, but that their requirement for hearing may not necessarily be the same as in mammals. [ABSTRACT FROM AUTHOR]

The tumour suppressor, Lethal (2) giant larvae [Lgl; also known as L(2)gl], is an evolutionarily conserved protein that was discovered in the vinegar fly Drosophila, where its depletion results in tissue overgrowth and loss of cell polarity. Lgl links cell polarity and tissue growth through regulation of the Notch and the Hippo signalling pathways. Lgl regulates the Notch pathway by inhibiting V-ATPase activity via Vap33. How Lgl regulates the Hippo pathway was unclear. In this current study, we show that V-ATPase activity inhibits the Hippo pathway, whereas Vap33 acts to activate Hippo signalling. Vap33 physically and genetically interacts with the actin cytoskeletal regulators RtGEF (Pix) and Git, which also bind to the Hippo protein (Hpo) and are involved in the activation of the Hippo pathway. Additionally, we show that the ADP ribosylation factor Arf79F (Arf1), which is a Hpo interactor, is involved in the inhibition of the Hippo pathway. Altogether, our data suggest that Lgl acts via Vap33 to activate the Hippo pathway by a dual mechanism: (1) through interaction with RtGEF, Git and Arf79F, and (2) through interaction and inhibition of the V-ATPase, thereby controlling epithelial tissue growth. [ABSTRACT FROM AUTHOR]

Both constitutive and inducible immune mechanisms are employed by hosts for defense against infection. Constitutive immunity allows for a faster response, but it comes with an associated cost that is always present. This trade-off between speed and fitness costs leads to the theoretical prediction that constitutive immunity will be favored where parasite exposure is frequent. We selected populations of Drosophila melanogaster under high parasite pressure from the parasitoid wasp Leptopilina boulardi. With RNA sequencing, we found the evolution of resistance in these populations was associated with them developing constitutively active humoral immunity, mediated by the larval fat body. Furthermore, these evolved populations were also able to induce gene expression in response to infection to a greater level, which indicates an overall more activated humoral immune response to parasitization. The anti-parasitoid immune response also relies on the JAK/STAT signaling pathway being activated in muscles following infection, and this induced response was only seen in populations that had evolved under high parasite pressure. We found that the cytokine Upd3, which induces this JAK/STAT response, is being expressed by immature lamellocytes. Furthermore, these immune cells became constitutively present when populations evolved resistance, potentially explaining why they gained the ability to activate JAK/STAT signaling. Thus, under intense parasitism, populations evolved resistance by increasing both constitutive and induced immune defenses, and there is likely an interplay between these two forms of immunity. Author summary: Immune defenses can be induced after infection or they may be constitutively active, even in uninfected individuals. As constitutive immunity is a more rapid response, theory predicts that it will be favored when animals frequently encounter parasites. When we subjected populations of Drosophila melanogaster to high rates of parasitization from its natural parasite, Leptopilina boulardi parasitoid wasps, we indeed observed that the immune response became constitutively active. Uninfected insects had an activated humoral immune response and produced cytokine-secreting immune cells that were normally induced after infection. However, we also found that these populations evolved a greater induced response. This included a greatly increased cytokine response after infection, suggesting that the constitutive activation of some aspects of the immune system may allow a greater induced response in other tissues. [ABSTRACT FROM AUTHOR]

The willistoni group of Drosophila is subdivided into the alagitans, bocainensis, and willistoni subgroups, and has been an important model for studying evolutionary processes in the Neotropics for decades. Phylogenetic studies place the bocainensis subgroup as a grade in relation to the monophyletic willistoni subgroup, although these included molecular or morphological data for up to 4 species of the 12 species included in the first subgroup. Here, we characterized the first nucleotide sequences for three mitochondrial and five nuclear genes of Drosophila bocainensis Pavan & da Cunha, 1947 and employed these for addressing the paraphyly of this subgroup under a coalescent approach. Our results still recovered this paraphyletic relationship, placing D. bocainensis, Drosophila capricorni Dobzhansky & Pavan, 1943 and Drosophila sucinea Patterson & Mainland, 1944 in a basal clade, which diverged around 6.81 million years ago. The relationship of Drosophila nebulosa Sturtevant, 1916 and Drosophila fumipennis Duda, 1925 as a sister clade to the willistoni subgroup was recovered. The possible causes of such paraphyly are discussed. [ABSTRACT FROM AUTHOR]

Ganaspis Foerster includes several cryptic species that are important larval parasitoids of the invasive pest Drosophila suzukii (Matsumura), spotted-wing drosophila (SWD). Drosophila suzukii , native to Asia, was first discovered in 2008 in North America and Europe, becoming a devastating pest of soft-skinned fruit crops. Biological control could be among the safest, most environmentally benign, and cost-effective methods for long-term and landscape-level management of this invasive pest. Foreign exploration in East Asia discovered several major larval D. suzukii parasitoids. One of them was initially described as Ganaspis brasiliensis (Ihering) and consisted of 2 major genetic groups (G1 and G3). The groups are now recognized as 2 different species, Ganaspis kimorum Buffington and Ganaspis lupini Buffington. The more host-specific species G. kimorum was selected and approved for field release in the United States in 2021 and has been widely released since 2022. Here, we provide a comprehensive overview of the parasitoid's taxonomy, current known distribution, biology, ecology, mass-rearing methods, and biological control potential. [ABSTRACT FROM AUTHOR]

A distinctive species in the family Drosophilidae, Drosophila ancora Okada, 1968, is redescribed from specimens from Vietnam, and transferred to the genus Dichaetophora Duda sensu lato. It is exceptional among Diptera for its labellar sclerites that in males have grown into a pair of heavily sclerotized, pointed lobes at the tip of the labellum, producing what appear to be chewing mandibles. This is analogous to the condition in the dolichopodid Melanderia Aldrich, but there it is not sexually dimorphic. The structures are doubtfully used in male-male aggression or in postcopulatory mate guarding. Based on their shapes and fit, it is proposed that the "mandibles" are used by males to grasp the tip of the female oviscapt during courtship or for the male to grasp the female wing edge while mounted. [ABSTRACT FROM AUTHOR]

Oviposition preference for spherical substrates has been reported in some insects but not in Drosophila species until the recent finding that Drosophila suzukii preferentially lays eggs on spherical surfaces with a smaller radius, whereas D. melanogaster does not. This finding raised two questions: (i) Was this trait specifically acquired in D. suzukii or lost in D. melanogaster? (ii) In the latter case, is it due to the long‐term laboratory culture using oviposition substrates with flat surfaces? To answer these questions, we examined the oviposition preference of three Drosophila species using the stocks recently established from wild individuals. As with D. suzukii, D. simulans and D. takahashii showed significant preference for spherical surfaces with a smaller radius, suggesting that this trait is shared by multiple Drosophila species. In contrast, D. melanogaster did not show any preference for either smaller or larger radii, showing that the preference already has been lost in the natural population of D. melanogaster. It may be possible that the loss of oviposition preference for spherical surfaces is involved in the evolutionary process of D. melanogaster becoming a human commensal. [ABSTRACT FROM AUTHOR]

Over 100 years of studies in Drosophila melanogaster and related species in the genus Drosophila have facilitated key discoveries in genetics, genomics, and evolution. While high-quality genome assemblies exist for several species in this group, they only encompass a small fraction of the genus. Recent advances in long-read sequencing allow high-quality genome assemblies for tens or even hundreds of species to be efficiently generated. Here, we utilize Oxford Nanopore sequencing to build an open community resource of genome assemblies for 101 lines of 93 drosophilid species encompassing 14 species groups and 35 sub-groups. The genomes are highly contiguous and complete, with an average contig N50 of 10.5 Mb and greater than 97% BUSCO completeness in 97/101 assemblies. We show that Nanopore-based assemblies are highly accurate in coding regions, particularly with respect to coding insertions and deletions. These assemblies, along with a detailed laboratory protocol and assembly pipelines, are released as a public resource and will serve as a starting point for addressing broad questions of genetics, ecology, and evolution at the scale of hundreds of species.

The PIWI-interacting RNA (piRNA) pathway prevents endogenous genomic parasites, i.e. transposable elements, from damaging the genetic material of animal gonadal cells. Specific regions in the genome, called piRNA clusters, are thought to define each species' piRNA repertoire and therefore its capacity to recognize and silence specific transposon families. The unistrand cluster flamenco (flam) is essential in the somatic compartment of the Drosophila ovary to restrict Gypsy-family transposons from infecting the neighbouring germ cells. Disruption of flam results in transposon de-repression and sterility, yet it remains unknown whether this silencing mechanism is present more widely. Here, we systematically characterise 119 Drosophila species and identify five additional flam-like clusters separated by up to 45 million years of evolution. Small RNA-sequencing validated these as bona-fide unistrand piRNA clusters expressed in somatic cells of the ovary, where they selectively target transposons of the Gypsy family. Together, our study provides compelling evidence of a widely conserved transposon silencing mechanism that co-evolved with virus-like Gypsy-family transposons. To control transposable elements, fruit flies rely on distinct genomic regions called piRNA clusters. Here, new piRNA clusters were identified across diverse Drosophila species, displaying a conserved and specialised role in the control of endogenous retroviruses in ovarian somatic cells. [ABSTRACT FROM AUTHOR]

Background: Behavior‐based manipulation is an essential part of Drosophila integrated pest management (IPM). Effective compounds are useful for improving the efficiency of baits and the development of attract‐and‐kill or push–pull strategies to manage Drosophila populations. Here, we investigated the olfactory behavior of two Drosophila species, as well as their pupal parasitoid, to volatiles from bananas, for the identification of effective compounds to control fly populations. Results: The results showed that overripe bananas were most attractive to both flies, with a higher attraction index (AI) in Drosophila melanogaster than in Drosophila suzukii. The profiles of volatile organic compounds (VOCs) from bananas with three different ripening stages were compared, and six VOCs were selected for behavioral tests. D. suzukii showed significantly different responses to isoamyl alcohol with D. melanogaster. The effects of ethyl butyrate and ethyl isovalerate on the two flies were dose‐dependent, with lower concentrations acting as repellent and higher concentrations acting as attractant. Isoamyl acetate, isoamyl butyrate and isoamyl isovalerate (0.005–0.05% v/v) were attractive to both flies. The parasitoid wasp Pachycrepoidus vindemmiae was repelled by isoamyl alcohol and ethyl butyrate, and attracted by ethyl isovalerate, but showed no significant response to isoamyl acetate, isoamyl butyrate and isoamyl isovalerate at the tested concentration. Conclusion: This study indicated that the behavioral response of Drosophila to the odor of chemical compounds is dose‐dependent. Isoamyl alcohol and isoamyl acetate at certain concentrations could be used as repellents, whereas ethyl isovalerate as an attractant in control strategy design for D. suzukii. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Background: Drosophila melanogaster is excellent animal model for understanding the molecular basis of human neurological and motor disorders. The experimental conditions and chamber design varied between studies. Moreover, most previously established paradigms focus on fly trace detection algorithm development. A comprehensive understanding on how fly behaves in the chamber is still lacking. Results: In this report, we established 74 unique behavior metrics quantifying spatiotemporal characteristics of adult fly locomotion and social behaviors, of which 49 were newly proposed. By the aiding of the developed analysis pipeline, Drosophila video tracking (DVT), we identified siginificantly different patterns of fly behavior confronted with different chamber height, fly density, illumination and experimental time. Meanwhile, three fly strains which are widely used as control lines, Canton-S(CS), w1118 and Oregon-R (OR), were found to exhibit distinct motion explosiveness and exercise endurance. Conclusions: We believe the proposed behavior metrics set and pipeline should help identify subtle spatial and temporal differences of drosophila behavior confronted with different environmental factors or gene variants. [ABSTRACT FROM AUTHOR]

Cryptic species represent a substantial fraction of the diversity of Drosophilidae, hampering studies on species ecologies and their evolution. Anthophilous species within the Drosophila lutzii group encompass some of the most widely distributed Neotropical lineages. Nevertheless, their ranges, ecologies, divergence times, and phylogenetic relationships are largely unknown. In this study, we analyzed the cryptic diversity of the lutzii species complex occurring in Southern Brazil and shed light on the ecological and evolutionary processes underlying their current patterns of coexistence. We used an integrative approach, evaluating molecular, ecological, and morphological traits under an evolutionary ecology framework. We documented the unexpected occurrence of D. alei in Southern Brazil, whose range was only known for the Andean region. Our phylogenetic analysis indicated that despite morphological similarities, D. alei is more closely related to D. denieri than to D. lutzii , and that divergence among these three species dates back to the Neogene (7.3 Mya). Niche modeling suggests that D. denieri and D. lutzii populations expanded their ranges and were established in Southern Brazil during the Quaternary (150 kya), being affected by similar paleoclimatic events. On the other hand, D. alei shows distinct abiotic requirements than D. denieri and D. lutzii , and environmental distribution models suggested a significant reduction in its suitable areas during the Quaternary, especially in Southern Brazil. This suggests that the current sympatry observed in this region likely reflects a secondary contact between the three species resulting from niche divergence processes. Altogether, these results advance the understanding of the distribution and phylogenetic relationships of Neotropical anthophilous Drosophila , revealing the interplay between ecological and historical factors in their speciation. [ABSTRACT FROM AUTHOR]

Drosophila melanogaster is an excellent model for dissecting innate immune signaling and functions. Humoral and cellular immune mechanisms in the fly take place in the hemolymph, where host defense components are secreted and act in response to microbial invaders. Studying hemolymph factors is critical for understanding the regulation of the host's antimicrobial immune system. Therefore, methods for extracting the fly hemolymph efficiently and in sufficient quantities are essential for isolating and characterizing immune proteins and peptides. Here, we describe a novel and simple hemolymph isolation protocol for single D. melanogaster male and female adults. This procedure substantially improves the already used technique and allows fly immunologists to explore innate immune hemolymph activity in D. melanogaster individuals. [ABSTRACT FROM AUTHOR]

Vertebrate podocytes and Drosophila nephrocytes display slit diaphragms, specialised cell junctions that are essential for the execution of the basic excretory function of ultrafiltration. To elucidate the mechanisms of slit diaphragm assembly we have studied their formation in Drosophila embryonic garland nephrocytes. These cells of mesenchymal origin lack overt apical-basal polarity. We find that their initial membrane symmetry is broken by an acytokinetic cell division that generates PIP2-enriched domains at their equator. The PIP2-enriched equatorial cortex becomes a favourable domain for hosting slit diaphragm proteins and the assembly of the first slit diaphragms. Indeed, when this division is either prevented or forced to complete cytokinesis, the formation of diaphragms is delayed to larval stages. Furthermore, although apical polarity determinants also accumulate at the equatorial cortex, they do not appear to participate in the recruitment of slit diaphragm proteins. The mechanisms we describe allow the acquisition of functional nephrocytes in embryos, which may confer on them a biological advantage similar to the formation of the first vertebrate kidney, the pronephros. [ABSTRACT FROM AUTHOR]

The difference in body size between females and males, or sexual size dimorphism (SSD), is ubiquitous, yet we have a poor understanding of the developmental genetic mechanisms that generate it and how these mechanisms may vary within and among species. Such an understanding of the genetic architecture of SSD is important if we are to evaluate alternative models of SSD evolution, but the genetic architecture is difficult to describe because SSD is a characteristic of populations, not individuals. Here, we overcome this challenge by using isogenic lineages of Drosophila to measure SSD for 196 genotypes. We demonstrate extensive genetic variation for SSD, primarily driven by higher levels of genetic variation for body size among females than among males. While we observe a general increase in SSD with sex-averaged body size (pooling for sex) among lineages, most of the variation in SSD is independent of sex-averaged body size and shows a strong genetic correlation with sex-specific plasticity, such that increased female-biased SSD is associated with increased body size plasticity in females. Our data are consistent with the condition dependence hypothesis of sexual dimorphism and suggest that SSD in Drosophila is a consequence of selection on the developmental genetic mechanisms that regulate the plasticity of body size. [ABSTRACT FROM AUTHOR]

Fruits, vegetables, and spices are natural sources of bioactive phytochemicals, such as polyphenols, carotenoids, flavonoids, curcuminoids, terpenoids, and capsaicinoids, possessing multiple health benefits and relatively low toxicity. These compounds found in the diet play a central role in organism development and fitness. Given the complexity of the whole-body response to dietary changes, invertebrate model organisms can be valuable tools to examine the interplay between genes, signaling pathways, and metabolism. Drosophila melanogaster, an invertebrate model with its extensively studied genome, has more than 70% gene homology to humans and has been used as a model system in biological studies for a long time. The notable advantages of Drosophila as a model system, such as their low maintenance cost, high reproductive rate, short generation time and lifespan, and the high similarity of metabolic pathways between Drosophila and mammals, have encouraged the use of Drosophila in the context of screening and evaluating the impact of phytochemicals present in the diet. Here, we review the benefits of Drosophila as a model system for use in the study of phytochemical ingestion and describe the previously reported effects of phytochemical consumption in Drosophila. [ABSTRACT FROM AUTHOR]