Smell is an ancient sensory system presented virtually in organisms from bacteria tohumans. In Drosophila odors elicit a variety of behavioral responses in relatively simple butsensitive olfactory system. An increasing number of mutants have been found to be defective inolfactory function. Genetic and molecular analysis of the olfactory system of the fruit fly haveidentified many molecular components, and have revealed some principles of its function andorganization
Metabolic syndrome (MetS) is a cluster of metabolic disturbances increasing a risk of cardiovascular diseases and diabetes 2 types. The main features of MetS include atherogenic dyslipidemia, elevated blood pressure, insulin resistance and elevated glucose levels, a pro-thrombotic state, pro-oxidant and pro-inflammatory states. Excessive consumption of high caloric food and sedentary lifestyle followed by overweight and obesity, as well as aging and stresses are major contributing factors to the MetS development. MeS affects between 10 and 84% of adults depending on the used MetS criteria and increases significantly a risk of cardiovascular diseases, diabetes 2 type and kidney diseases. Patients with metabolic disorders like obesity, diabetes, cardiovascular, and liver disease may have a higher risk of infection of COVID-19 with significantly worse prognosis and outcomes in these patients. In recent years, the fruit fly, Drosophila melanogaster, has been actively used to study human metabolic disorders as a cost-effective and expedient model. Drosophila belongs to insects with full metamorphosis and its life cycle includes four developmental stages: embryo, larva, pupa, and adult flies. Each developmental stage has its own specific advantages and can be used to study metabolic homeostasis. Studies of metabolic disturbances in Drosophila and mammalian models along with humans have demonstrated that flies and small mammalian models have many similarities with humans in basic metabolic functions and share many molecular mechanisms which regulate these metabolic processes. In this paper, we describe the advantages and limitations of Drosophila models of metabolic syndrome and obesity in light of physiological and biochemical similarities and differences between insects and mammals.
AbstractGenetically engineered gene drives (geGD) are potentially powerful tools for suppressing or even eradicating populations of pest insects. Before living geGD insects can be released into the environment, they must pass an environmental risk assessment to ensure that their release will not cause unacceptable harm to non‐targeted entities of the environment. A key research question concerns the likelihood that nontarget species will acquire the functional GD elements; such acquisition could lead to reduced abundance or loss of those species and to a disruption of the ecosystem services they provide. The main route for gene flow is through hybridization between the geGD insect strain and closely related species that co‐occur in the area of release and its expected dispersal. Using the invasive spotted‐wing drosophila, Drosophila suzukii, as a case study, we provide a generally applicable strategy on how a combination of interspecific hybridization experiments, behavioral observations, and molecular genetic analyses can be used to assess the potential for hybridization.
Chromatin is known to undergo extensive remodeling during nuclear reprogramming. However, the factors and mechanisms involved in this remodeling are still poorly understood and current experimental approaches to study it are not best suited for molecular and genetic analyses. Here we report on the use of Drosophila preblastodermic embryo extracts (DREX) in chromatin remodeling experiments. Our results show that incubation of somatic nuclei in DREX induces changes in chromatin organization similar to those associated with nuclear reprogramming, such as rapid binding of the germline specific linker histone dBigH1 variant to somatic chromatin, heterochromatin reorganization, changes in the epigenetic state of chromatin, and nuclear lamin disassembly. These results raise the possibility of using the powerful tools of Drosophila genetics for the analysis of chromatin changes associated with this essential process. ; This work was supported by grants from MINECO (BFU2015-65082-P), the Generalitat de Catalunya (SGR2014-204), and the European Community FEDER program. This work was carried out within the framework of the "Centre de Referència en Biotecnologia" of the Generalitat de Catalunya. EŠ acknowledges receipt of a NEWFELPRO Fellowship of the Croatian Government and Ministry of Science and Education within EU FP7 Programme framework. ; Peer reviewed
Chromatin is known to undergo extensive remodeling during nuclear reprogramming. However, the factors and mechanisms involved in this remodeling are still poorly understood and current experimental approaches to study it are not best suited for molecular and genetic analyses. Here we report on the use of Drosophila preblastodermic embryo extracts (DREX) in chromatin remodeling experiments. Our results show that incubation of somatic nuclei in DREX induces changes in chromatin organization similar to those associated with nuclear reprogramming, such as rapid binding of the germline specific linker histone dBigH1 variant to somatic chromatin, heterochromatin reorganization, changes in the epigenetic state of chromatin, and nuclear lamin disassembly. These results raise the possibility of using the powerful tools of Drosophila genetics for the analysis of chromatin changes associated with this essential process. ; This work was supported by grants from MINECO (BFU2015-65082-P), the Generalitat de Catalunya (SGR2014-204), and the European Community FEDER program. This work was carried out within the framework of the "Centre de Referència en Biotecnologia" of the Generalitat de Catalunya. EŠ acknowledges receipt of a NEWFELPRO Fellowship of the Croatian Government and Ministry of Science and Education within EU FP7 Programme framework.
Mit der Beschreibung von Drosophila orena spec. nov. erhöht sich die Zahl der Spezies in der Artgruppe melanogaster auf sieben. Vier dieser Arten wurden seit 1971 deskribiert. Diese Entdeckung bestätigt die Hypothese der afrikanischen Herkunft von D. melanogaster. Interessant ist die Feststellung, daß die Untergruppe melanogaster im Laufe ihrer Entwicklung sowohl ubiquitäre, kosmopolitische und kolonisierende Arten als auch spezialisierte Arten mit einer schmalen ökologischen Nische bilden konnte.Nomenklatorische Handlungenorena Tsacas & David, 1978 (Drosophila (Sophophora)), spec. n. ; The description of Drosophila orena spec. nov. adds a 7th species to the melanogaster sub-group. Four of these species have been described since 1971. This discovery confirms the hypothesis of an African origin of D. melanogaster. It is interesting to note that, during its evolution, the melanogaster sub-group was able to produce both ubiquitous, cosmopolitan, colonizing species and specialized ones with a narrow ecological niche. Nomenclatural Actsorena Tsacas & David, 1978 (Drosophila (Sophophora)), spec. n.
The influence of oncogenic phenomena on the ecology and evolution of animal species is becoming an important research topic. Similar to host–pathogen interactions, cancer negatively affects host fitness, which should lead to the selection of host control mechanisms, including behavioral traits that best minimize the proliferation of malignant cells. Social behavior is suggested to influence tumor progression. While the ecological benefits of sociality in gregarious species are widely acknowledged, only limited data are available on the role of the social environment on cancer progression. Here, we exposed adult Drosophila, with colorectal-like tumors, to different social environments. We show how subtle variations in social structure have dramatic effects on the progression of tumor growth. Finally, we reveal that flies can discriminate between individuals at different stages of tumor development and selectively choose their social environment accordingly. Our study demonstrates the reciprocal links between cancer and social interactions and how sociality may impact health and fitness in animals and its potential implications for disease ecology. ; This work was supported by the ANR (Blanc project EVOCAN to F.T. and project DROSONET to F.M. and C.S.), the CNRS (INEE and INSB), Fondation ARC (1555286 to J.M. and F.M.), The French league against Cancer (M27218 to J.M.), IDEEV program (to F.M.), by an International Associated Laboratory Project France/Australia, by the French-Australian Science Innovation Collaboration Program Early Career Fellowship (B.U.), by André Hoffmann (Fondation MAVA), Fyssen Foundation (to F.M. and E.H. D.) and the French Government (fellowship 2015–155 to M.D.).
GAGA factor plays important roles during Drosophila embryogenesis and its maternal contribution is essential for early development. Here, the role of GAGA factor was studied in 3rd instar larvae using depletion and overexpression conditions in wing disc and transcriptome analysis. We found that genes changing expression were different to those previously described using GAGA mutants in embryos. No apparent phenotypes on GAGA depletion could usually be observed at larval stages in imaginal discs but a strong effect on salivary gland polytene chromosomes was observed. In the adult, GAGA depletion produced many defects like abnormal cell proliferation in the wing, impaired dorsal closure and resulted in homeotic transformation of abdominal segment A5. Unexpectedly, no effects on Ultrabithorax expression were observed. Short overexpression of GAGA factor in 3rd instar larvae also resulted in activation of a set of genes not previously described to be under GAGA regulation, and in lethality at pupa. Our results suggest a little contribution of GAGA factor on gene transcription in wing discs and a change of the genes regulated in comparison with embryo. GAGA factor activity thus correlates with the global changes in gene expression that take place at the embryo-to-larva and, later, at the larva-to-pupa transitions. ; This work was supported by grants of the Ministerio de Educación y Ciencia of the Spanish Government (BFU-2007-64395/BMC), the MICINN (CSD2006-49 and BFU2009-07111) and the Generalitat de Catalunya (SGR2009-1023). M.B. was supported by I3P CPG_06_0034 contract from CSIC, and grant BFU-2007-64395/BMC contract of the Spanish Government. D.P. was supported by an FPU fellowship from the Spanish Government ; Peer Reviewed
Housekeeping genes of animal genomes cluster in the same chromosomal regions. It has long been suggested that this organization contributes to their steady expression across all the tissues of the organism. Here, we show that the activity of Drosophila housekeeping gene promoters depends on the expression of their neighbors. By measuring the expression of ∼85,000 reporters integrated in Kc167 cells, we identified the best predictors of expression as chromosomal contacts with the promoters and terminators of active genes. Surprisingly, the chromatin composition at the insertion site and the contacts with enhancers were less informative. These results are substantiated by the existence of genomic "paradoxical" domains, rich in euchromatic features and enhancers, but where the reporters are expressed at low level, concomitant with a deficit of interactions with promoters and terminators. This indicates that the proper function of housekeeping genes relies not on contacts with long distance enhancers but on spatial clustering. Overall, our results suggest that spatial proximity between genes increases their expression and that the linear architecture of the Drosophila genome contributes to this effect. ; This work was supported by the Spanish Ministry of Economy and Competitiveness, "Centro de Excelencia Severo Ochoa 2013-2017," SEV-2012-0208, Plan Nacional BFU2012-37168, NWO-ALW VICI, ERC Advanced Grant 293662 (B.v.S.), ERC Synergy Grant 609989 (G.J.F.), and the People Programme (Marie Curie Actions) of the European Union's Seventh Framework Programme (FP7/2007-2013) under REA grant agreement no. 608959 (R.C.).
The brain's impotence to utilize long-chain fatty acids as fuel, one of the dogmas in neuroscience, is surprising, since the nervous system is the tissue most energy consuming and most vulnerable to a lack of energy. Challenging this view, we here show in vivo that loss of the Drosophila carnitine palmitoyltransferase 2 (CPT2), an enzyme required for mitochondrial β-oxidation of long-chain fatty acids as substrates for energy production, results in the accumulation of triacylglyceride-filled lipid droplets in adult Drosophila brain but not in obesity. CPT2 rescue in glial cells alone is sufficient to restore triacylglyceride homeostasis, and we suggest that this is mediated by the release of ketone bodies from the rescued glial cells. These results demonstrate that the adult brain is able to catabolize fatty acids for cellular energy production. ; This work was partially supported by the Flanders Fund for Scientific Research (FWO G 0.666.10N), NEUROBRAINNET IAP 7/16, Flemish Government Methusalem Grant, Spanish Ministry of Science (SAF2010-14906) and Innovation Ingenio-Consolider (CSD2010-00045) and Spanish Ministry of Economy and Competitiveness (SAF2013-45392). ; Peer Reviewed
