Dopaminergic Ric GTPase activity impacts amphetamine sensitivity and sleep quality in a dopamine transporter-dependent manner in Drosophila melanogaster

AbstractDopamine (DA) is required for movement, sleep, and reward, and DA signaling is tightly controlled by the presynaptic DA transporter (DAT). Therapeutic and addictive psychostimulants, including methylphenidate (Ritalin; MPH), cocaine, and amphetamine (AMPH), markedly elevate extracellular DA via their actions as competitive DAT inhibitors (MPH, cocaine) and substrates (AMPH). DAT silencing in mice and invertebrates results in hyperactivity, reduced sleep, and blunted psychostimulant responses, highlighting DAT’s essential role in DA-dependent behaviors. DAT surface expression is not static; rather it is dynamically regulated by endocytic trafficking. PKC-stimulated DAT endocytosis requires the neuronal GTPase, Rit2, and Rit2 silencing in mouse DA neurons impacts psychostimulant sensitivity. However, it is unknown whether or not Rit2-mediated changes in psychostimulant sensitivity are DAT-dependent. Here, we leveraged Drosophila melanogaster to test whether the Drosophila Rit2 ortholog, Ric, impacts dDAT function, trafficking, and DA-dependent behaviors. Orthologous to hDAT and Rit2, dDAT and Ric directly interact, and the constitutively active Ric mutant Q117L increased dDAT surface levels and function in cell lines and ex vivo Drosophila brains. Moreover, DAergic RicQ117L expression caused sleep fragmentation in a DAT-dependent manner, but had no effect on total sleep and daily locomotor activity. Importantly, we found that Rit2 is required for AMPH-stimulated DAT internalization in mouse striatum, and that DAergic RicQ117L expression significantly increased Drosophila AMPH sensitivity in a DAT-dependent manner, suggesting a conserved impact of Ric-dependent DAT trafficking on AMPH sensitivity. These studies support that the DAT/Rit2 interaction impacts both baseline behaviors and AMPH sensitivity, potentially by regulating DAT trafficking.

Download Full-text

A GENETICALLY DISTINCT FORM OF CYCLIC AMP PHOSPHODIESTERASE ASSOCIATED WITH CHROMOMERE 3D4 IN DROSOPHILA MELANOGASTER

Genetics ◽

10.1093/genetics/91.3.521 ◽

1979 ◽

Vol 91 (3) ◽

pp. 521-535

Author(s):

John A Kiger ◽

Eric Golanty

Keyword(s):

Drosophila Melanogaster ◽

Cyclic Amp ◽

Structural Gene ◽

Regulatory Gene ◽

Heat Stability ◽

Normal Female ◽

Dependent Manner ◽

Cyclic Amp Phosphodiesterase ◽

Heat Stable ◽

Camp Levels

ABSTRACT Two cyclic AMP phosphodiesterase enzymes (E.C.3.1.4.17) are present in homogenates of adult Drosophila melanogaster. The two enzymes differ from one another in heat stability, affinity for Mg++, Ca++ activation and molecular weight. They do not differ markedly in their affinities for cyclic AMP, and both exhibit anomalous Michaelis-Menten kinetics. The more heatlabile enzyme is controlled in a dosage-dependent manner by chromomere 3D4 of the X chromosome and is absent in flies that are deficient for chromomere 3D4. Chromomere 3D4 is also necessary for the maintenance of normal cAMP levels, for male fertility, and for normal female fertility and oogenesis. The structural gene(s) for the more heat-stable enzyme is located outside of chromomeres 3C12-3D4. Whether 3D4 contains a structural gene, or a regulatory gene necessary for the presence of the labile enzyme, remains to be determined.

Download Full-text

Study on the Sleep-Improvement Effects of Hemerocallis citrina Baroni in Drosophila melanogaster and Targeted Screening to Identify Its Active Components and Mechanism

Foods ◽

10.3390/foods10040883 ◽

2021 ◽

Vol 10 (4) ◽

pp. 883

Author(s):

Yuxuan Liang ◽

Riming Huang ◽

Yongchun Chen ◽

Jing Zhong ◽

Jie Deng ◽

...

Keyword(s):

Drosophila Melanogaster ◽

High Resolution Mass Spectrometry ◽

Sleep Time ◽

Network Pharmacology ◽

Dependent Manner ◽

Bioactive Components ◽

Active Components ◽

Edible Plant ◽

Hemerocallis Citrina ◽

Ultrahigh Performance Liquid Chromatography

Hemerocallis citrina Baroni (HC) is an edible plant in Asia, and it has been traditionally used for sleep-improvement. However, the bioactive components and mechanism of HC in sleep-improvement are still unclear. In this study, the sleep-improvement effect of HC hydroalcoholic extract was investigated based on a caffeine-induced insomnia model in Drosophila melanogaster (D. melanogaster), and the ultrahigh-performance liquid chromatography coupled with electrospray ionization quadrupole Orbitrap high-resolution mass spectrometry (UHPLC-ESI-Orbitrap-MS) and network pharmacology strategy were further combined to screen systematically the active constituents and mechanism of HC in sleep-improvement. The results suggested HC effectively regulated the number of nighttime activities and total sleep time of D. melanogaster in a dose-dependent manner and positively regulated the sleep bouts and sleep duration of D. melanogaster. The target screening suggested that quercetin, luteolin, kaempferol, caffeic acid, and nicotinic acid were the main bioactive components of HC in sleep-improvements. Moreover, the core targets (Akt1, Cat, Ple, and Sod) affected by HC were verified by the expression of the mRNA of D. melanogaster. In summary, this study showed that HC could effectively regulate the sleep of D. melanogaster and further clarifies the multi-component and multi-target features of HC in sleep-improvement, which provides a new insight for the research and utilization of HC.

Download Full-text

The P-element-induced silencing effect of KP transposons is dose dependent in Drosophila melanogaster

Genome ◽

10.1139/g11-023 ◽

2011 ◽

Vol 54 (9) ◽

pp. 752-762 ◽

Cited By ~ 7

Author(s):

Alireza Sameny ◽

John Locke

Keyword(s):

Drosophila Melanogaster ◽

Critical Role ◽

Mutagenic Effect ◽

P Element ◽

Dependent Manner ◽

Concentration Dependent Manner ◽

P Elements ◽

Single Well ◽

Dose Dependent

Transposable elements are found in the genomes of all eukaryotes and play a critical role in altering gene expression and genome organization. In Drosophila melanogaster, transposable P elements are responsible for the phenomenon of hybrid dysgenesis. KP elements, a deletion-derivative of the complete P element, can suppress this mutagenic effect. KP elements can also silence the expression of certain other P-element-mediated transgenes in a process called P-element-dependent silencing (PDS), which is thought to involve the recruitment of heterochromatin proteins. To explore the mechanism of this silencing, we have mobilized KP elements to create a series of strains that contain single, well-defined KP insertions that show PDS. To understand the quantitative role of KP elements in PDS, these single inserts were combined in a series of crosses to obtain genotypes with zero, one, or two KP elements, from which we could examine the effect of KP gene dose. The extent of PDS in these genotypes was shown to be dose dependent in a logarithmic rather than linear fashion. A logarithmic dose dependency is consistent with the KP products interacting with heterochromatic proteins in a concentration-dependent manner such that two molecules are needed to induce gene silencing.

Download Full-text

Virgin Coconut (Cocos nucifera) Oil Attenuates Rotenone-Induced Toxicity in Fruit Flies (Drosophila melanogaster)

Journal of Basic and Social Pharmacy Research ◽

10.52968/27458357 ◽

2021 ◽

Vol 2 (1) ◽

pp. 26-37

Author(s):

O.O. Dosumu ◽

◽

E.N. Akang ◽

O.K. Idowu ◽

G.J. Adeyemi

Keyword(s):

Drosophila Melanogaster ◽

Cocos Nucifera ◽

Coconut Oil ◽

Redox Status ◽

Fruit Flies ◽

Dependent Manner ◽

Toxicity Assay ◽

Behavioural Test ◽

Locomotor Deficits ◽

Dose Dependent

Background: Parkinson's disease (PD) is a multifactorial neurodegenerative disease with pathogenic mechanisms traceable to oxidative damage and mitochondrial dysfunction. Rotenone, a chemical compound commonly found in pesticides, has been found to inhibit mitochondrial complex-I and initiate PD-like symptoms in mammals and several invertebrates. Virgin Coconut Oil (VCNO) obtained from the coconut fruit has been found to possess anti-oxidative and anti-inflammatory properties. Objectives: The present study evaluated the effect of VCNO on rotenone-induced Parkinsonism in fruit flies- Drosophila melanogaster (D. melanogaster). Methods: Canton special (CS) strains of D. melanogaster, aged between 1 to 3 days were orally exposed for 7 days to 0, 250, 500 and 750 μM rotenone diet for toxicity assay, and 0, 2.5, 5 and 10 % w/w VCNO diet for longevity assay. Thereafter, 5 % VCNO diet was selected for evaluation against 500 μM rotenone. Subsequently, behavioural test (negative geotaxis), markers for redox status and enzyme activities were evaluated. Results: The results showed that rotenone induced toxicity in the flies, while VCNO increased the lifespan of D. melanogaster in a dose-dependent manner. In addition, VCNO ameliorated rotenone-induced locomotor deficits, elevated MDA, as well as the depleted GSH levels. It also mitigated the inhibited activities of SOD, CAT and ATPase in the flies. Conclusions: VCNO protected D. melanogaster against rotenone-induced toxicity by extending longevity, preventing locomotor deficits and reducing oxidative stress.

Download Full-text

Abscisic acid induction of GTP hydrolysis in maize coleoptile plasma membranes

Functional Plant Biology ◽

10.1071/pp98009 ◽

1998 ◽

Vol 25 (5) ◽

pp. 539 ◽

Cited By ~ 4

Author(s):

Helen R. Irving

Keyword(s):

Abscisic Acid ◽

G Protein ◽

G Proteins ◽

Pertussis Toxin ◽

Plasma Membranes ◽

Dependent Manner ◽

Gtpase Activity ◽

Heterotrimeric G Proteins ◽

Gtp Hydrolysis ◽

Maize Coleoptile

Since receptor-coupled G proteins increase GTP hydrolysis (GTPase) activity upon ligands binding to the receptor, a study was undertaken to determine if abscisic acid (ABA) induced such an effect. Plasma membranes isolated from etiolated maize (Zea mays L.) coleoptiles were enriched in GTPase activity relative to microsomal fractions. Vanadate was included in the assay to inhibit the high levels of vanadate sensitive low affinity GTPases present. Under these conditions, GTPase activity was enhanced by Mg2+, stimulated by mastoparan, and inhibited by GTPγS indicating the presence of either monomeric or heterotrimeric G proteins. The combination of NaF and AlCl3 is expected to inhibit heterotrimeric G protein activity but had little effect on GTPase activity in maize coleoptile membranes. Cholera toxin enhanced basal GTPase activity, confirming the presence of heterotrimeric G proteins in maize plasma membranes. Pertussis toxin also slightly enhanced basal GTPase activity in maize membranes. Abscisic acid enhanced GTPase activity optimally at 5 mmol/L Mg2+ in a concentration dependent manner by 1.5-fold at 10 µmol/L and up to three-fold at 100 µmol/L ABA. Abscisic acid induced GTPase activity was inhibited by GTPγS, the combination of NaF and AlCl3, and pertussis toxin. Overall, these results are typical of a receptor-coupled G protein responding to its ligand.

Download Full-text

The Intracellular Symbiont Wolbachia pipientis Enhances Recombination in a Dose-Dependent Manner

Insects ◽

10.3390/insects11050284 ◽

2020 ◽

Vol 11 (5) ◽

pp. 284

Author(s):

Kaeli N. Bryant ◽

Irene L. G. Newton

Keyword(s):

Drosophila Melanogaster ◽

Horizontal Transmission ◽

Wolbachia Infection ◽

Wolbachia Strain ◽

Dependent Manner ◽

Predator Prey ◽

Wolbachia Pipientis ◽

Intracellular Symbiont ◽

Dose Dependent ◽

Classical Genetics

Wolbachia pipientis is an intracellular alphaproteobacterium that infects 40%–60% of insect species and is well known for host reproductive manipulations. Although Wolbachia are primarily maternally transmitted, evidence of horizontal transmission can be found in incongruent host–symbiont phylogenies and recent acquisitions of the same Wolbachia strain by distantly related species. Parasitoids and predator–prey interactions may indeed facilitate the transfer of Wolbachia between insect lineages, but it is likely that Wolbachia are acquired via introgression in many cases. Many hypotheses exist to explain Wolbachia prevalence and penetrance, such as nutritional supplementation, protection from parasites, protection from viruses, or direct reproductive parasitism. Using classical genetics, we show that Wolbachia increase recombination in infected lineages across two genomic intervals. This increase in recombination is titer-dependent as the wMelPop variant, which infects at higher load in Drosophila melanogaster, increases recombination 5% more than the wMel variant. In addition, we also show that Spiroplasma poulsonii, another bacterial intracellular symbiont of D. melanogaster, does not induce an increase in recombination. Our results suggest that Wolbachia infection specifically alters its host’s recombination landscape in a dose-dependent manner.

Download Full-text

Transcriptional Adaptor ADA3 of Drosophila melanogaster Is Required for Histone Modification, Position Effect Variegation, and Transcription

Molecular and Cellular Biology ◽

10.1128/mcb.01307-07 ◽

2007 ◽

Vol 28 (1) ◽

pp. 376-385 ◽

Cited By ~ 18

Author(s):

Benjamin Grau ◽

Cristina Popescu ◽

Laura Torroja ◽

Daniel Ortuño-Sahagún ◽

Imre Boros ◽

...

Keyword(s):

Drosophila Melanogaster ◽

Histone Acetyltransferase ◽

Gene Dosage ◽

Position Effect ◽

Position Effect Variegation ◽

Dependent Manner ◽

Histone H4 ◽

Chromosomal Pairing ◽

Effect Variegation ◽

A Subunit

ABSTRACT The Drosophila melanogaster gene diskette (also known as dik or dAda3) encodes a protein 29% identical to human ADA3, a subunit of GCN5-containing histone acetyltransferase (HAT) complexes. The fly dADA3 is a major contributor to oogenesis, and it is also required for somatic cell viability. dADA3 localizes to chromosomes, and it is significantly reduced in dGcn5 and dAda2a, but not in dAda2b, mutant backgrounds. In dAda3 mutants, acetylation at histone H3 K9 and K14, but not K18, and at histone H4 K12, but not K5, K8, and K16, is significantly reduced. Also, phosphorylation at H3 S10 is reduced in dAda3 and dGcn5 mutants. Variegation for white (w m4 ) and scute (Hw v ) genes, caused by rearrangements of X chromosome heterochromatin, is modified in a dAda3 + gene-dosage-dependent manner. The effect is not observed with rearrangements involving Y heterochromatin (bw D ), euchromatin (Scutoid), or transvection effects on chromosomal pairing (white and zeste interaction). Activity of scute gene enhancers, targets for Iroquoi transcription factors, is abolished in dAda3 mutants. Also, Iroquoi-associated phenotypes are sensitive to dAda3 + gene dosage. We conclude that dADA3 plays a role in HAT complexes which acetylate H3 and H4 at specific residues. In turn, this acetylation results in chromatin structure effects of certain rearrangements and transcription of specific genes.

Download Full-text

Debcl, a Proapoptotic Bcl-2 Homologue, Is a Component of the Drosophila melanogaster Cell Death Machinery

The Journal of Cell Biology ◽

10.1083/jcb.148.4.703 ◽

2000 ◽

Vol 148 (4) ◽

pp. 703-714 ◽

Cited By ~ 105

Author(s):

Paul A. Colussi ◽

Leonie M. Quinn ◽

David C.S. Huang ◽

Michelle Coombe ◽

Stuart H. Read ◽

...

Keyword(s):

Cell Death ◽

Drosophila Melanogaster ◽

Mammalian Cells ◽

Cultured Cells ◽

Gene Dosage ◽

Family Members ◽

Ectopic Expression ◽

Dependent Manner ◽

Proapoptotic Protein ◽

Main Components

Bcl-2 family of proteins are key regulators of apoptosis. Both proapoptotic and antiapoptotic members of this family are found in mammalian cells, but no such proteins have been described in insects. Here, we report the identification and characterization of Debcl, the first Bcl-2 homologue in Drosophila melanogaster. Structurally, Debcl is similar to Bax-like proapoptotic Bcl-2 family members. Ectopic expression of Debcl in cultured cells and in transgenic flies causes apoptosis, which is inhibited by coexpression of the baculovirus caspase inhibitor P35, indicating that Debcl is a proapoptotic protein that functions in a caspase-dependent manner. debcl expression correlates with developmental cell death in specific Drosophila tissues. We also show that debcl genetically interacts with diap1 and dark, and that debcl-mediated apoptosis is not affected by gene dosage of rpr, hid, and grim. Biochemically, Debcl can interact with several mammalian and viral prosurvival Bcl-2 family members, but not with the proapoptotic members, suggesting that it may regulate apoptosis by antagonizing prosurvival Bcl-2 proteins. RNA interference studies indicate that Debcl is required for developmental apoptosis in Drosophila embryos. These results suggest that the main components of the mammalian apoptosis machinery are conserved in insects.

Download Full-text

Female and male genetic contributions to post-mating immune defence in female Drosophila melanogaster

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2010.0937 ◽

2010 ◽

Vol 277 (1700) ◽

pp. 3649-3657 ◽

Cited By ~ 41

Author(s):

Sarah M. Short ◽

Brian P. Lazzaro

Keyword(s):

Drosophila Melanogaster ◽

Genetic Variation ◽

Sexual Conflict ◽

Bacterial Pathogens ◽

Dependent Manner ◽

Immune Defence ◽

Trade Off ◽

Providencia Alcalifaciens ◽

Genetic Contributions ◽

Evolution Of Immunity

Post-mating reduction in immune defence is common in female insects, and a trade-off between mating and immunity could affect the evolution of immunity. In this work, we tested the capacity of virgin and mated female Drosophila melanogaster to defend against infection by four bacterial pathogens. We found that female D. melanogaster suffer post-mating immunosuppression in a pathogen-dependent manner. The effect of mating was seen after infection with two bacterial pathogens ( Providencia rettgeri and Providencia alcalifaciens ), though not after infection with two other bacteria ( Enterococcus faecalis and Pseudomonas aeruginosa ). We then asked whether the evolution of post-mating immunosuppression is primarily a ‘female’ or ‘male’ trait by assaying for genetic variation among females for the degree of post-mating immune suppression they experience and among males for the level of post-mating immunosuppression they elicit in their mates. We also assayed for an interaction between male and female genotypes to test the specific hypothesis that the evolution of a trade-off between mating and immune defence in females might be being driven by sexual conflict. We found that females, but not males, harbour significant genetic variation for post-mating immunosuppression, and we did not detect an interaction between female and male genotypes. We thus conclude that post-mating immune depression is predominantly a ‘female’ trait, and find no evidence that it is evolving under sexual conflict.

Download Full-text