Regulated inositol synthesis is critical for balanced metabolism and development in Drosophila melanogaster

ABSTRACT Myo-inositol is a precursor of the membrane phospholipid, phosphatidylinositol (PI). It is involved in many essential cellular processes including signal transduction, energy metabolism, endoplasmic reticulum stress, and osmoregulation. Inositol is synthesized from glucose-6-phosphate by myo-inositol-3-phosphate synthase (MIPSp). The Drosophila melanogaster Inos gene encodes MIPSp. Abnormalities in myo-inositol metabolism have been implicated in type 2 diabetes, cancer, and neurodegenerative disorders. Obesity and high blood (hemolymph) glucose are two hallmarks of diabetes, which can be induced in Drosophila melanogaster third-instar larvae by high-sucrose diets. This study shows that dietary inositol reduces the obese-like and high-hemolymph glucose phenotypes of third-instar larvae fed high-sucrose diets. Furthermore, this study demonstrates Inos mRNA regulation by dietary inositol; when more inositol is provided there is less Inos mRNA. Third-instar larvae with dysregulated high levels of Inos mRNA and MIPSp show dramatic reductions of the obese-like and high-hemolymph glucose phenotypes. These strains, however, also display developmental defects and pupal lethality. The few individuals that eclose die within two days with striking defects: structural alterations of the wings and legs, and heads lacking proboscises. This study is an exciting extension of the use of Drosophila melanogaster as a model organism for exploring the junction of development and metabolism.

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Copine A Interacts with Actin Filaments and Plays a Role in Chemotaxis and Adhesion

Cells ◽

10.3390/cells8070758 ◽

2019 ◽

Vol 8 (7) ◽

pp. 758 ◽

Cited By ~ 1

Author(s):

Matthew J. Buccilli ◽

April N. Ilacqua ◽

Mingxi Han ◽

Andrew A. Banas ◽

Elise M. Wight ◽

...

Keyword(s):

Protein Function ◽

Actin Filaments ◽

Model Organism ◽

Dependent Manner ◽

Developmental Defects ◽

Calcium Dependent ◽

Cellular Processes ◽

Eukaryotic Organisms ◽

Von Willebrand

Copines make up a family of calcium-dependent, phospholipid-binding proteins found in numerous eukaryotic organisms. Copine proteins consist of two C2 domains at the N-terminus followed by an A domain similar to the von Willebrand A domain found in integrins. We are studying copine protein function in the model organism, Dictyostelium discoideum, which has six copine genes, cpnA-cpnF. Previous research showed that cells lacking the cpnA gene exhibited a cytokinesis defect, a contractile vacuole defect, and developmental defects. To provide insight into the role of CpnA in these cellular processes, we used column chromatography and immunoprecipitation to isolate proteins that bind to CpnA. These proteins were identified by mass spectrometry. One of the proteins identified was actin. Purified CpnA was shown to bind to actin filaments in a calcium-dependent manner in vitro. cpnA− cells exhibited defects in three actin-based processes: chemotaxis, cell polarity, and adhesion. These results suggest that CpnA plays a role in chemotaxis and adhesion and may do so by interacting with actin filaments.

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FlyBase: updates to the Drosophila melanogaster knowledge base

Nucleic Acids Research ◽

10.1093/nar/gkaa1026 ◽

2020 ◽

Vol 49 (D1) ◽

pp. D899-D907 ◽

Cited By ~ 1

Author(s):

Aoife Larkin ◽

Steven J Marygold ◽

Giulia Antonazzo ◽

Helen Attrill ◽

Gilberto dos Santos ◽

...

Keyword(s):

Drosophila Melanogaster ◽

Knowledge Base ◽

Fast Track ◽

Model Organism ◽

Disease Models ◽

Online Database ◽

Experimental Tool

Abstract FlyBase (flybase.org) is an essential online database for researchers using Drosophila melanogaster as a model organism, facilitating access to a diverse array of information that includes genetic, molecular, genomic and reagent resources. Here, we describe the introduction of several new features at FlyBase, including Pathway Reports, paralog information, disease models based on orthology, customizable tables within reports and overview displays (‘ribbons’) of expression and disease data. We also describe a variety of recent important updates, including incorporation of a developmental proteome, upgrades to the GAL4 search tab, additional Experimental Tool Reports, migration to JBrowse for genome browsing and improvements to batch queries/downloads and the Fast-Track Your Paper tool.

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Structure and Regulation of the Salivary Gland Secretion Protein Gene Sgs-1 of Drosophila melanogaster

Genetics ◽

10.1093/genetics/153.2.753 ◽

1999 ◽

Vol 153 (2) ◽

pp. 753-762

Author(s):

Günther E Roth ◽

Sigrid Wattler ◽

Hartmut Bornschein ◽

Michael Lehmann ◽

Günter Korge

Keyword(s):

Drosophila Melanogaster ◽

Tandem Repeats ◽

Transcriptional Start Site ◽

Regulatory Elements ◽

Coding Region ◽

Band Shift ◽

Salivary Gland Secretion ◽

Enhancer Binding Protein ◽

Factor Secretion ◽

Third Instar Larvae

Abstract The Drosophila melanogaster gene Sgs-1 belongs to the secretion protein genes, which are coordinately expressed in salivary glands of third instar larvae. Earlier analysis had implied that Sgs-1 is located at the 25B2-3 puff. We cloned Sgs-1 from a YAC covering 25B2-3. Despite using a variety of vectors and Escherichia coli strains, subcloning from the YAC led to deletions within the Sgs-1 coding region. Analysis of clonable and unclonable sequences revealed that Sgs-1 mainly consists of 48-bp tandem repeats encoding a threonine-rich protein. The Sgs-1 inserts from single λ clones are heterogeneous in length, indicating that repeats are eliminated. By analyzing the expression of Sgs-1/lacZ fusions in transgenic flies, cis-regulatory elements of Sgs-1 were mapped to lie within 1 kb upstream of the transcriptional start site. Band shift assays revealed binding sites for the transcription factor fork head (FKH) and the factor secretion enhancer binding protein 3 (SEBP3) at positions that are functionally relevant. FKH and SEBP3 have been shown previously to be involved in the regulation of Sgs-3 and Sgs-4. Comparison of the levels of steady state RNA and of the transcription rates for Sgs-1 and Sgs-1/lacZ reporter genes indicates that Sgs-1 RNA is 100-fold more stable than Sgs-1/lacZ RNA. This has implications for the model of how Sgs transcripts accumulate in late third instar larvae.

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Influence of Dopamine on Fluorescent Advanced Glycation End Products Formation Using Drosophila melanogaster

Biomolecules ◽

10.3390/biom11030453 ◽

2021 ◽

Vol 11 (3) ◽

pp. 453

Author(s):

Ana Filošević Vujnović ◽

Katarina Jović ◽

Emanuel Pištan ◽

Rozi Andretić Waldowski

Keyword(s):

Drosophila Melanogaster ◽

Advanced Glycation End Products ◽

Model Organism ◽

Covalent Modification ◽

Advanced Glycation ◽

Biomarkers Of Aging ◽

Glycation End Products ◽

End Products

Non-enzymatic glycation and covalent modification of proteins leads to Advanced Glycation End products (AGEs). AGEs are biomarkers of aging and neurodegenerative disease, and can be induced by impaired neuronal signaling. The objective of this study was to investigate if manipulation of dopamine (DA) in vitro using the model protein, bovine serum albumin (BSA), and in vivo using the model organism Drosophila melanogaster, influences fluorescent AGEs (fAGEs) formation as an indicator of dopamine-induced oxidation events. DA inhibited fAGEs-BSA synthesis in vitro, suggesting an anti-oxidative effect, which was not observed when flies were fed DA. Feeding flies cocaine and methamphetamine led to increased fAGEs formation. Mutants lacking the dopaminergic transporter or the D1-type showed further elevation of fAGEs accumulation, indicating that the long-term perturbation in DA function leads to higher production of fAGEs. To confirm that DA has oxidative properties in vivo, we fed flies antioxidant quercetin (QUE) together with methamphetamine. QUE significantly decreased methamphetamine-induced fAGEs formation suggesting that the perturbation of DA function in vivo leads to increased oxidation. These findings present arguments for the use of fAGEs as a biomarker of DA-associated neurodegenerative changes and for assessment of antioxidant interventions such as QUE treatment.

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PRESENCE OF A BASE LINE LEVEL OF SISTER CHROMATID EXCHANGES IN SOMATIC CELLS OF DROSOPHILA MELANOGASTER IN VIVO AND IN VITRO

Genetics ◽

10.1093/genetics/100.2.259 ◽

1982 ◽

Vol 100 (2) ◽

pp. 259-278

Author(s):

Hideo Tsuji

Keyword(s):

Drosophila Melanogaster ◽

Sister Chromatid ◽

Ganglion Cells ◽

Sister Chromatid Exchanges ◽

Base Line ◽

Cell Cycles ◽

Chromatid Exchanges ◽

Third Instar Larvae

ABSTRACT Sister chromatid exchanges (SCEs) under in vivo and in vitro conditions were examined in ganglion cells of third-instar larvae of Drosophila melanogaster (Oregon-R). In the in vivo experiment, third-instar larvae were fed on synthetic media containing 5-bromo-2′-deoxyuridine (BrdUrd). After two cell cycles, ganglia were dissected and treated with colchicine. In the in vitro experiment, the ganglia were also incubated in media containing BrdUrd for two cell cycles, and treated with colchicine. SCEs were scored in metaphase stained with Hoechst 33258 plus Giemsa. The frequencies of SCEs stayed constant in the range of 25-150 vg/ml and 0.25-2.5 vg/ml of BrdUrd in vivo and in vitro, respectively. SCEs gradually increased at higher concentrations, strongly suggesting that at least a fraction of the detected SCEs are spontaneous. The constant levels of SCE frequency were estimated, on the average, at 0.103 per cell per two cell cycles for females and 0.101 for males in vivo and at 0.096 for females and 0.091 for males in vitro. No difference was found in the SCE frequency between sexes at any of the BrdUrd concentrations. The analysis for the distribution of SCEs within chromosomes revealed an extraordinarily high proportion of the SCEs at the junctions between euchromatin and heterochromatin; the remaining SCEs were preferentially localized in the euchromatic regions of the chromosomes and in the heterochromatic Y chromosome. These results were largely inconsistent with those of Gatti et al. (1979).

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Quantitative investigation reveals distinct phases in Drosophila sleep

Communications Biology ◽

10.1038/s42003-021-01883-y ◽

2021 ◽

Vol 4 (1) ◽

Author(s):

Xiaochan Xu ◽

Wei Yang ◽

Binghui Tian ◽

Xiuwen Sui ◽

Weilai Chi ◽

...

Keyword(s):

Drosophila Melanogaster ◽

General Pattern ◽

Model Organism ◽

Infrared Camera ◽

Fruit Fly ◽

Genetic Dissection ◽

Power Law Distribution ◽

Quantitative Investigation ◽

Waking Up ◽

Set Up

AbstractThe fruit fly, Drosophila melanogaster, has been used as a model organism for the molecular and genetic dissection of sleeping behaviors. However, most previous studies were based on qualitative or semi-quantitative characterizations. Here we quantified sleep in flies. We set up an assay to continuously track the activity of flies using infrared camera, which monitored the movement of tens of flies simultaneously with high spatial and temporal resolution. We obtained accurate statistics regarding the rest and sleep patterns of single flies. Analysis of our data has revealed a general pattern of rest and sleep: the rest statistics obeyed a power law distribution and the sleep statistics obeyed an exponential distribution. Thus, a resting fly would start to move again with a probability that decreased with the time it has rested, whereas a sleeping fly would wake up with a probability independent of how long it had slept. Resting transits to sleeping at time scales of minutes. Our method allows quantitative investigations of resting and sleeping behaviors and our results provide insights for mechanisms of falling into and waking up from sleep.

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Learning the distribution of single-cell chromosome conformations in bacteria reveals emergent order across genomic scales

Nature Communications ◽

10.1038/s41467-021-22189-x ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Joris J. B. Messelink ◽

Muriel C. F. van Teeseling ◽

Jacqueline Janssen ◽

Martin Thanbichler ◽

Chase P. Broedersz

Keyword(s):

Single Cell ◽

Caulobacter Crescentus ◽

Model Organism ◽

Super Resolution ◽

Chromosome Organization ◽

General Strategy ◽

Cell Axis ◽

Cellular Processes ◽

Emergent Order ◽

Genomic Clusters

AbstractThe order and variability of bacterial chromosome organization, contained within the distribution of chromosome conformations, are unclear. Here, we develop a fully data-driven maximum entropy approach to extract single-cell 3D chromosome conformations from Hi–C experiments on the model organism Caulobacter crescentus. The predictive power of our model is validated by independent experiments. We find that on large genomic scales, organizational features are predominantly present along the long cell axis: chromosomal loci exhibit striking long-ranged two-point axial correlations, indicating emergent order. This organization is associated with large genomic clusters we term Super Domains (SuDs), whose existence we support with super-resolution microscopy. On smaller genomic scales, our model reveals chromosome extensions that correlate with transcriptional and loop extrusion activity. Finally, we quantify the information contained in chromosome organization that may guide cellular processes. Our approach can be extended to other species, providing a general strategy to resolve variability in single-cell chromosomal organization.

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