Microplastic exposure disturbs sleep structure,reduces lifespan,and decreases ovary size in Drosophila melanogaster

The organ-specific toxicity resulting from microplastic(MP)exposure has been extensively explored,particularly concerning the gut,liver,testis,and lung.However,under natural conditions,these effects are not restricted to specific organs or tissues.Investigating whether MP exposure presents a systemic threat to an entire organism,impacting factors such as lifespan,sleep,and fecundity,is essential.In this study,we investigated the effects of dietary exposure to two different doses of MPs(1–5μm)using the terrestrial model organism Drosophila melanogaster.Results indicated that the particles caused gut damage and remained within the digestive system.Continuous MP exposure significantly shortened the lifespan of adult flies.Even short-term exposure disrupted sleep patterns,increasing the length of daytime sleep episodes.Additionally,one week of MP exposure reduced ovary size,with a trend towards decreased egg-laying in mated females.Although MPs did not penetrate the brain or ovaries,transcriptome analysis revealed altered gene expression in these tissues.In the ovary,Gene Ontology(GO)analysis indicated genotoxic effects impacting inflammation,circadian regulation,and metabolic processes,with significant impacts on extracellular structure-related pathways.In the brain,GO analysis identified changes in pathways associated with proteolysis and carbohydrate metabolism.Overall,this study provides compelling evidence of the systemic negative effects of MP exposure,highlighting the urgent need to address and mitigate environmental MP pollution.

Naringin ameliorates H_(2)O_(2)-induced oxidative damage in cells and prolongs the lifespan of female Drosophila melanogaster via the insulin signaling pathway

Naringin exists in a wide range of Chinese herbal medicine and has proven to possess several pharmacological properties.In this study,PC12,HepG2 cells,and female Drosophila melanogaster were used to investigate the antioxidative and anti-aging effects of naringin and explore the underlying mechanisms.The results showed that naringin inhibited H_(2)O_(2)-induced decline in cell viability and decreased,the content of reactive oxygen species in cells.Meanwhile,naringin prolonged the lifespan of flies,enhanced the abilities of climbing and the resistance to stress,improved the activities of antioxidant enzymes,and decreased malondialdehyde content.Naringin also improved intestinal barrier dysfunction and reduced abnormal proliferation of intestinal stem cells.Moreover,naringin down-regulated the mRNA expressions of inr,chico,pi 3k,and akt-1,and up-regulated the mRNA expressions of dilp2,dilp3,dilp5,and foxo,thereby activating autophagy-related genes and increasing the number of lysosomes.Furthermore,the mutant stocks assays and computer molecular simulation results further indicated that naringin delayed aging by inhibiting the insulin signaling(IIS)pathway and activating the autophagy pathway,which was consistent with the result of network pharmacological predictions.

Effects of Sodium Cyclohexyl Sulfamate on Growth and Development of Drosophila melanogaster

[Objectives]This study was conducted to investigate the effects of different concentrations of sodium cyclohexyl sulfamate on the growth and development of Drosophila melanogaster.[Methods]Different concentrations of sodium cyclohexyl sulfamate were added to the culture medium,and the effects of different concentrations of sodium cyclohexyl sulfamate on the development time and weight of D.melanogaster in various life stages were statistically analyzed.[Results]High concentration of sodium cyclohexyl sulfamate delayed the time of pupation and eclosion of D.melanogaster,which made D.melanogaster lose weight.The number of male D.melanogaster in the first generation was much larger than that of female individuals,which indicated that the effect of sodium cyclohexyl sulfamate on male D.melanogaster was greater than that of female individuals.In a word,high concentration of sodium cyclohexyl sulfamate significantly inhibited the growth and development of D.melanogaster.[Conclusions]This study provides some reference data for the research perspective of food additives and the safe use of sodium cyclohexyl sulfamate.

Research on the Karyotype and Evolution of Drosophila melanogaster Species Group

Mitotic metaphase chromosomes of 34 species of Drosophila melanogaster species group were examined. Certain new karyotypes were described for the first time, and their evolutionary and interspecific genetic relationships among 8 subgroups of D. melanogaster species group were analyzed systematically. The results were as follows. The basic karyotype of elegans subgroup was type A. The karyotypes of eugracilis subgroup, melanogaster subgroup, and ficusphila subgroup were all type C. The karyotypes of takahashii subgroup and suzukii subgroup were both type C and type D. The montium subgroup had six kinds of karyotypes types B, C, C＇, D, D＇, and E. The ananassae subgroup had three kinds of karyotypes： types F, G, and H. Thus, the melanogaster species group was classified into five pedigrees based on the diversity of these karyotypes： 1） elegans; 2） eugracilis-melanogasterficusphila; 3） takkahashii-suzukii; 4） montium; 5） ananassae. The above-mentioned results in karyotypic evolution were consistent with those of DNA sequence analysis reported by Yang except for the elegans subgroup and this subgroup was considered as the ancestral subgroup. Karyotype analysis of the same drosophila from different isofemale lines indicated that the same Drosophila from different places showed karyotypic variation which might be due to different geographical environment and evolutionary degree or interaction between the two factors.

Simulation of gene pyramiding in Drosophila melanogaster

Gene pyramiding has been successfully practiced in plant breeding for developing new breeds or lines in which favorable genes from several different lines were integrated. But it has not been used in animal breeding, and some theoretical investigation and simulation analysis with respect to its strategies, feasibility and efficiency are needed before it can be implemented in animals. In this study, we used four different pure lines of Drosophila melanogaster, each of which is homozygous at a specific mutant gene with a visible effect on phenotype, to simulate the gene pyramiding process and analyze the duration and population size required in different pyramiding strategies. We finally got the ideal individuals, which are homozygous at the four target genes simultaneously. This study demonstrates that gene pyramiding is feasible in animal breeding and the interaction between genes may affect the final results.

Ganoderma lucidum spore oil(GLSO),a novel antioxidant,extends the average life span in Drosophila melanogaster

In ancient China,Ganoderma lucidum was believed to be a medical fungus that could increase lifespan.Recently,pharmacologic studies have found that polysaccharide peptides and triterpenoids extracted from Ganoderma lucidum have various physiological effects as active compounds.However,the effects of spore oil isolated from Ganoderma lucidum remains unknown.In this study,the biological effects of Ganoderma lucidum spore oil(GLSO)were evaluated using a Drosophila melanogaster model.Compared with untreated groups,groups treated with GLSO had significantly longer average and maximum lifespan in both normal conditions and under oxidative stress.The activities of various antioxidant enzymes were measured to determine the antioxidant effect of GLSO.GLSO treatment markedly enhanced total superoxide dismutase(SOD)and catalase(CAT)activity and decreased levels of malondialdehyde(MDA).Further,we found dose-dependent increases in the mRNA expression of Cu,Zn-SOD,Mn-SOD,and CAT in GLSO-treated groups.These results suggest that GLSO may effectively eliminate free radicals and extend lifespan in Drosophila.Future work should investigate the value of GLSO as a functional food for the prevention of aging in larger animal models.

Factors affecting mito-nuclear codon usage interactions in the OXPHOS system of Drosophila melanogaster

Codon usage bias varies considerably among genomes and even within the genes of the same genome. In eukaryotic organisms, energy production in the form of oxidative phosphorylation （OXPHOS） is the only process under control of both nuclear and mitochondrial genomes. Although factors affecting codon usage in a single genome have been studied, this has not occurred when both interactional genomes are involved. Consequently, we investigated whether or not other factors influence codon usage of coevolved genes. We used Drosophila melanogaster as a model organism. Our χ^2 test on the number of codons of nuclear and mitochondrial genes involved in the OXPHOS system was significantly different （χ^2= 7945.16, P 〈 0.01）. A plot of effective number of codons against GC3s content of nuclear genes showed that few genes lie on the expected curve, indicating that codon usage was random. Correspondence analysis indicated a significant correlation between axis 1 and codon adaptation index （R = 0.947, P 〈 0.01） in every nuclear gene sequence. Thus, codon usage bias of nuclear genes appeared to be affected by translational selection. Correlation between axis 1 coordinates and GC content （R = 0.814, P 〈 0.01） indicated that the codon usage of nuclear genes was also affected by GC composition. Analysis of mitochondrial genes did not reveal a significant correlation between axis 1 and any parameter. Statistical analyses indicated that codon usages of both nDNA and mtDNA were subjected to context-dependent mutations.

Stability and Refolding of Prophenol Oxidase Protein with 2-Propanol in Drosophila melanogaster

Phenol oxidase in Drosophila melanogaster occurs as folded phase precursors designated as prophenol oxidase A1 and A3, and prophenol oxidase is activated with alcohol, especially 2-propanol, within a few minutes as unfolded-phase in vitro. To clarify a common effect of alcohols on proteins and peptides, the extract containing prophenol oxidase protein was prepared. Phenol oxidase activity activated with 2-propanol has been maintained stable at least 24 hours remains as it is. Protein of prophenol oxidase was not denatured opposite hypnoses known as the instability of protein with alcohol. Activated prophenol oxidase with 2-propanol remain enzyme activity with no aggregation, stable, renaturation, and the refolding phenomena occurred around the active phase within the catalytic active center of prophenol oxidase protein in Drosophila melanogaster. This study is important to induce the wide range applications of the effect in many fields for rational drag design.

Positive effect of porphyrans on the lifespan and vitality of Drosophila melanogaster

The effects of degraded porphyran (P1) and natural porphyran (P) on the lifespan and vitality of Drosophila melanogaster are studied. The porphyrans, added daily to the food medium at 0.2% and 1% concentrations, can significantly increase the lifespan in average of 55.79 and 58.23 d in 0.2% P1 diet females and 1% P1 diet males, extending by 12.29% and 8.60% over the corresponding controls, respectively. The effects of porphyrans on D. melanogaster in heat-stress condition were also examined, and found a remarkable increase in survival time. The results which are consistently associated with the use of porphyrans are related to their free radical scavenger action. Considerable increase in vitality demonstrated that vitalities of middle-aged fly (assessed by measuring their mating capacity) was observed after porphyrans addition. Therefore, porphyrans are effective in reducing the rate of aging, and P1 in low molecular weight is better than natural P.

Observation of Biological Character of Drosophila melanogaster Meigen on Cherry and Screening of Its Insecticides

Indoor rearing observation and efficacy test of insecticides were conducted in 2010 to understand the biochemical characteristics of Drosophila rnelano-gaster and high efficient insecticides against the insect pest. The results showed that D. melanogaster had preference to eight kinds of fruits with proliferation. Fe-male adults of D. melanogaster laid eggs under epidermis of cherry fruits and newly hatched larvae caused damage on fruits. When the temperatures were （ 18 ±2） ℃ and （ 23 ± 2 ） ℃, the egg stage was 2.4 - 3.0 and 1.2 - 1.8 d ; the larval stage was 11.2 - 12.2 and 5.6 - 6.5 d; the papal stage was 9.5 - 10.6 and 5.0 - 6.2 d ; one generation was 23.1 - 25.4 and 12.8 - 14.2 d, respectively. Four insecticides （ including 1% emamectin benzoate EC 3 000 times dilution, 90% crys- tal trichlorfon 1 000 times dilution, 40% phoxim EC 1 500 times dilution and 25% buprofezin WP 2 000 times dilution） had higher control effects against D. mela-nogaster, with mortalities of 85.00% - 100.00%, 96.67% - 100.00% and 100.00% after insecticide application for 1, 3 and 6 h, respectively.

Effects of SPNE on Growth,Development and Correlated Traits of Five Drosophila melanogaster Strains

Five homozygous strains of Drosophila melanogaster were used as the experimental materials and treated with SPNE （ Special Plant Nutritional Element）. D. melanogaster larvae were incubated at 18 ℃ in Drosophila culture medium with SPNE addition. The results showed that larva emergence, pupa emergence and adult emergence in SPNE treatment were earlier than that in control. SPNE treatment accelerated the growth and development, shortened the life cycle, significantly increased the quantity of offspring and slightly improved the weight of D. melanogaster, which confirmed that SPNE posed significant effects on D. melanogaster. This study laid foundation for the breeding of D. melanogaster and other insects and provided new materials and a new approach for broadening the application of SPNE.

Activation of Prophenol Oxidase PHOX-S with Limited Proteolysis in Drosophila Melanogaster

Prophenol oxidase isoform A1 was isolated from Drosophila melanogaster （The sequence has been deposited in GenBank data base under accession number AB557586） PHOX-S strain, and its characteristics and activation mechanism were determined. The NH2-terminal region of PHOX-S A1 was determined to be comprised of 15 amino acids with the following sequence MTNMKMKMKAMMR. Comparison of an alignment in the known prophenol oxidase protein sequences from Drosophila melanogaster strains showed high homology in the copper-binding sequences at the Cu （A） site of the active center. Limited proteolysis takes place between Arg-50 and Val-51. Therefore, it is concluded that prophenol oxidase PHOX-S protein was evolved at the upstream, but no evolved at the central site in Drosophila melanogaster.

Microevolution of Mitochondrial Cytochrome oxidase subunit I in Drosophila melanogaster at ＂Evolution Canyon＂, Israel

We determined the sequence of mitochondrial Cytochrome oxidase subunit I （CO1） in two Drosophila melanogaster strains originating at ＂Evolution Canyon＂, Israel. CO1 nucleotide sequences from two iso-female strains, 2-1 and 6-1, were 1,534 and 1,543 base-pairs, respectively. In each strain, ATAA was used in initiation of translation. Exchange rates for nucleotide and amino acid sequences were larger in the 6-1 strain than in the 2-1 strain when Oregon-R was used as the standard. Non-synonymous exchange rate was larger than synonymous exchange rate among the three strains.

Recombinogenic Effect of the Ternary Complex of Copper（II） with Doxycycline and 1,10-Phenanthroline on Somatic Cells of Drosophila melanogaster

In the search for new anti-tumor agents, exploiting features such as the flexibility of coordination modes of metals have become an alternative strategy for synthesizing pharmaceuticals. It has been shown that the CuDP （copper（II）, doxycycline, and 1,10-phenanthroline） complex cleaves DNA strands by an oxidative mechanism and by intercalating the major groove, resulting in a cytotoxic action. The objective of this study was to assess the mutageinc/recombinogenic effects of the CuDP complex in vivo using the SMART （Somatic Mutation and Recombination Test） in Drosophila melanogaster. Treatments were carried out with third instar larvae at the standard cross and high bioactivation cross using three concentrations of CuDP （6.92, 13.84 or 27.67 mM）. The mutagenic doxorubicin （0.4 mM） was used as a positive control and reverse osmosis water as a negative control. For each compound, marked trans-heterozygous and balanced heterozygous individuals were analyzed to determine the mutational and recombinogenic events occurring in the cells, We found that CuDP significantly increased the frequencies of mutant cells in both standard and high bioactivation crosses, mostly by induction of recombination. These data show that CuDP is a direct recombinogenic agent that is independent of bioactivation,

Effects of a Carbonated Soft Drink on Epitheial Tumor Incidence in Drosophila melanogaster

Diet represents an important risk factor for tumor development and numerous food dyes have been tested for their carcinogenic potential. Caramel IV colorant and its byproduct, the 4-methylimidazole （4-MI）, are part of the composition of cola soft drinks, although in undefined concentration. Considering that this concentration depends on the manufacturing place, we aimed to evaluate the potential carcinogenic activity of cola soft drinks from Brazil, Canada, Egypt and Netherlands, through the test for detection of epithelial tumor clones （warts） in somatic cells of Drosophila melanogaster. We used 72-hour larvae resulting from the crossing of wts/TM3, Sb^1 virgin females and mwh/mwh males. Larvae were exposed to the media containing the cola soft drinks for 48 hours and the analysis was performed in adults after transformation. Cola soft drinks from Brazil significantly induced epithelial tumor in D. melanogaster, while those from Canada, Egypt and Netherlands did not. In fact, the concentration of 4-MI is higher in cola soft drink commercialized in Brazil. Our results highlight the importance of investigating the toxic potential of current drinks, which may correlate with the rising incidence of malignant diseases.

Inhibition of foxo and minibrain in Dopaminergic Neurons Can Model Aspects of Parkinson Disease in Drosophila melanogaster

Symptoms of Parkinson Disease (PD), the second most common neurodegenerative disease, emerge due to degeneration of dopaminergic neurons. Recently, a genome wide study revealed a role for a foxo transcription factor in PD. In the model organism Drosophila melanogaster, we have attempted 1) to inhibit the sole Drosophila homologue of foxo through the directed expression of a stable inducible RNAi transgene and 2) to indirectly increase foxo transcription activity through the inhibition of the kinase minibrain (mnb), a foxo transcriptional inhibitor. To evaluate the lifetime consequences upon the flies, longevity assays and locomotion over time assays were conducted. The inhibition of foxo by foxo-RNAi decreases life span significantly when expressed under the control of Tyrosine Hydroxylase-Gal4 (TH-Gal4). The targeted expression of mnb-RNAi, in the dopaminergic neurons, with an expected loss of suppression of foxo transcriptional activity, results in a significant loss of climbing ability. Thus alteration of foxo activity, both by RNA-inhibition and by down-regulation of an inhibitor of foxo, minibrain, produces novel Drosophila models of Parkinson Disease.

Increased life-span of Drosophila melanogaster by Flavonoids from Scutellariabaicalensis Georgi induced by hydrogen peroxide

Objective： To explore the effects and mechanisms of flavonoids from Scutellaria baicalensis Georgi in hydrogenperoxide （H2O2） induced Drosophila melanogaster model. Method： H2O2 induced Drosophila melanogaster agingmodel was used to study the effects of flavonoids from Scutellaria baicalensis Georgi. Secondly, the effects ofbaicalein and wogonin on mRNA expressions were examined. Results： Our results found that baicalein andwogonin could extend the life-spans of H2O2 induced Drosophila melanogaster aging model via increased mRNAexpressions of superoxide dismutase catalase and rosy. Conclusion： Baicalein and wogonin could extend life-spansof H2O2 induced Drosophila melanogaster aging model through increasing mRNA expressions of superoxidedismutase, catalase and rosy.

Adenine nucleotide translocase 2(Ant2)is required for individualization of spermatogenesis of Drosophila melanogaster

Successful completion of spermatogenesis is crucial for the perpetuation of the species.In Drosophila,spermatid individualization,a process involving changes in mitochondrial structure and function is critical to produce functional mature sperm.Ant2,encoding a mitochondrial adenine nucleotide translocase,is highly expressed in male testes and plays a role in energy metabolism in the mitochondria.However,its molecular function remains unclear.Here,we identified an important role of Ant2 in spermatid individualization.In Ant2 knockdown testes,spermatid individualization complexes composed of F-actin cones exhibited a diffuse distribution,and mature sperms were absent in the seminal vesicle,thus leading to male sterility.The most striking effects in Ant2-knockdown spermatids were decrease in tubulin polyglycylation and disruption of proper mitochondria derivatives function.Excessive apoptotic cells were also observed in Ant2-knockdown testes.To further investigate the phenotype of Ant2 knockdown in testes at the molecular level,complementary transcriptome and proteome analyses were performed.At the mRNA level,868 differentially expressed genes were identified,of which 229 genes were upregulated and 639 were downregulated induced via Ant2 knockdown.iTRAQ-labeling proteome analysis revealed 350 differentially expressed proteins,of which 117 proteins were upregulated and 233 were downregulated.The expression of glutathione transferase(GstD5,GstE5,GstE8,and GstD3),proteins involved in reproduction were significantly regulated at both the mRNA and protein levels.These results indicate that Ant2 is crucial for spermatid maturation by affecting mitochondrial morphogenesis.

Molecular toxicity and defense mechanisms induced by silver nanoparticles in Drosophila melanogaster

The widely use of silver nanoparticles(AgNPs) as antimicrobial agents gives rise to potential environmental risks. AgNPs exposure have been reported to cause toxicity in animals.Nevertheless, the known mechanisms of AgNPs toxicity are still limited. In this study, we systematically investigated the toxicity of AgNPs exposure using Drosophila melanogaster.We show here that AgNPs significantly decreased Drosophila fecundity, the third-instar larvae weight and rates of pupation and eclosion in a dose-dependent manner. AgNPs reduced fat body cell viability in MTT(3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide)assays. AgNPs caused DNA damage in hemocytes and S2 cells. Interestingly, the mRNA levels of the entire metallothionein gene family were increased under AgNPs exposure as determined by RNA-seq analysis and validated by qRT-PCR, indicating that Drosophila responded to the metal toxicity of AgNPs by producing metallothioneins for detoxification. These findings provide a better understanding of the mechanisms of AgNPs toxicity and may provide clues to effect on other organisms, including humans.

Genome editing in Drosophila melanogaster： from basic genome engineering to the multipurpose CRISPR-Cas9 system

Nowadays, genome editing tools are indispensable for studying gene function in order to increase our knowledge of biochemical processes and disease mechanisms. The extensive availability of mutagenesis and transgenesis tools make Drosophila melanogaster an excellent model organism for geneticists. Early mutagenesis tools relied on chemical or physical methods,ethyl methane sulfonate(EMS) and X-rays respectively, to randomly alter DNA at a nucleotide or chromosomal level. Since the discovery of transposable elements and the availability of the complete fly genome, specific genome editing tools, such as P-elements, zinc-finger nucleases(ZFNs) and transcription activator-like effector nucleases(TALENs), have undergone rapid development. Currently, one of the leading and most effective contemporary tools is the CRISPR-cas9 system made popular because of its low cost, effectiveness, specificity and simplicity of use. This review briefly addresses the most commonly used mutagenesis and transgenesis tools in Drosophila, followed by an in-depth review of the multipurpose CRISPR-Cas9 system and its current applications.