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...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.展开更多
Ergothioneine is a natural amino acid with powerful antioxidant activity.Previous studies have demonstrated that ergothioneine can increase the lifespan of Drosophila melanogaster and Caenorhabditis elegans,and enhanc...Ergothioneine is a natural amino acid with powerful antioxidant activity.Previous studies have demonstrated that ergothioneine can increase the lifespan of Drosophila melanogaster and Caenorhabditis elegans,and enhance telomerase activity.In present study,the metagenomics sequencing and quantitative real-time polymerase chain reaction analysis were employed to characterize the composition and diversity of gut microbiome in aging flies.And the alterations in the gut barrier,gut morphology,and other gut physiological indicators of aging flies were evaluated.Here,the results showed that ergothioneine induced little variations in gut microbiota composition in flies at mid-life,and significant alterations in the gut microbiota populations were only observed in flies at late-life.And ergothioneine attenuated age-related gut injuries,including decreasing reactive oxygen species levels in intestinal enterocytes,reduction of intestinal cells death,and preservation of gut integrity in aging flies.Ergothioneine also improved the gut morphology by preserving the structure and shape of cell organelles and inducing the intestinal autophagy.And activation of intestinal autophagy also contributed to the longevity effect mediated by ergothioneine in an unidentified mechanism.展开更多
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 an...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.展开更多
[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 ...[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.展开更多
Neuroscience and neurology research is dominated by experimentation with rodents.Around 75%of neurology disease-associated genes have orthologs in Drosophila mel-anogaster,the fruit fly amenable to complex neurologica...Neuroscience and neurology research is dominated by experimentation with rodents.Around 75%of neurology disease-associated genes have orthologs in Drosophila mel-anogaster,the fruit fly amenable to complex neurological and behavioral investiga-tions.However,non-vertebrate models including Drosophila have so far been unable to significantly replace mice and rats in this field of studies.One reason for this situ-ation is the predominance of gene overexpression(and gene loss-of-function)meth-odologies used when establishing a Drosophila model of a given neurological disease,a strategy that does not recapitulate accurately enough the genetic disease condi-tions.I argue here the need for a systematic humanization approach,whereby the Drosophila orthologs of human disease genes are replaced with the human sequences.This approach will identify the list of diseases and the underlying genes that can be adequately modeled in the fruit fly.I discuss the neurological disease genes to which this systematic humanization approach should be applied and provide an example of such an application,and consider its importance for subsequent disease modeling and drug discovery in Drosophila.I argue that this paradigm will not only advance our un-derstanding of the molecular etiology of a number of neurological disorders,but will also gradually enable researchers to reduce experimentation using rodent models of multiple neurological diseases and eventually replace these models.展开更多
The purpose of this study was to explore the potential of the development and application of Paecilomyces hepiali,a fungus with edible and medicinal value,as a foodborne antioxidant and anti-aging agent.Its n-butanol ...The purpose of this study was to explore the potential of the development and application of Paecilomyces hepiali,a fungus with edible and medicinal value,as a foodborne antioxidant and anti-aging agent.Its n-butanol extract(PHE)from rice cultures was selected for anti-aging experiment because of significant free radical scavenging activity in vitro.In vivo,PHE could significantly prolong the mean lifespan,50%survival days,and the maximum lifespan of Drosophila on a high-fat diet.It is amazing that the mean lifespan increased from 19.1 days to 32.9 days,50%survival days increased from 15.7 days to 34.3 days,and the maximum lifespan extended from 44.7 days to 52.7 days,when the high-fat female Drosophila model was fed with 10μg/mL PHE.Further research showed that PHE reduced the accumulation of peroxide products and increased the activity of antioxidant enzymes.Then,through antioxidant activity tracking,dimerumic acid(compound 1,the IC_(50) value of 3.4μg/mL on DPPH free radicals scavenging activity),4,5-dihydroxy-3-methoxypentanoic acid(compound 2,new compound),and thymidine(compound 3)were isolated from PHE.It is worth mentioning that dimerumic acid,the major antioxidant compound of PHE(content up to 3%),was discovered in P.hepiali for the first time.It was concluded that PHE showed excellent anti-aging activity at a very low concentration on fat diet-induced high fat Drosophila melanogaster,and dimerumic acid may be its main material basis.These results indicated that PHE had the potential to be developed as antioxidant and anti-aging agent in the healthcare industry.展开更多
The conditional mutations in drosophila were obtained by γ-irradiation and selected using the test for dominant lethality. The conditional mutations survive under permissive genetic conditions and, additionally, comm...The conditional mutations in drosophila were obtained by γ-irradiation and selected using the test for dominant lethality. The conditional mutations survive under permissive genetic conditions and, additionally, commence to display novel properties. One of such properties is a recessive lethality. Ten conditional mutations that displayed recessive lethality were mapped with the help of a standard set of deletions. Half mutations contained two and more lethal defects. The fact that a large number of the lethal defects are associated with one mutation suggests that γ-irradiation is the most unlikely cause of the defects. One of the conditional mutations carried four lethal regions and had a Small barrel (Smba) visual phenotype. The Smba phenotype in the Smba/ In(2LR) Cy strain is inherited according to a parental type and disappears in the Smba/In(2LR) Pm strain. Lethality in two of the four lethal regions also disappears in this strain. A separate experiment was conducted to clarify how these regions lost a lethal manifestation after the In(2LR) Cy chromosome in the Smba/In(2LR) Cy strain was replaced with the In(2LR) Pm chromosome. The process of disappearance of the Smba phenotype was also observed in three Smba/In(2LR) Cy substocks. These data suggest that the regions of multiple recessive lethality emerge in a secondary manner under the effect of the earlier formed radiation-induced mutation in ontogene. It is assumed that the recessive lethal regions are the ontogenes with an altered DNA conformation. The conformation in ontogenes is changed in the germline cells during a regular “editing” of the individual development program.展开更多
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 relationsh...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.展开更多
[ Objective ] The aim of this study was to investigate the infectivity of Nosema bombycis to drosophila, which offered a new vision for systematical studies on the infection mechanism of Nosema bombycis, and also prov...[ Objective ] The aim of this study was to investigate the infectivity of Nosema bombycis to drosophila, which offered a new vision for systematical studies on the infection mechanism of Nosema bombycis, and also provided reference for the bio-control effect of Nosema bombycis. [ Method ] Nosema bombycis was used to feed wild type and mutant drosophila, and the morphological observation of Nosema bombycis in drosophila body fluid was also analyzed by calcofluor white M2R fluorescent staining. [ Result] Nosema bombycis could infect drosophila, and the number of Nosema bombycis in the infected mutant drosophila was higher than that in wild type drosophila. [ Conclusion ] Nosema bombycis can infect drosophila, which provides primary reference for studies on the infectivity of Nosema bombycis to other hosts and also lays a foundation for further study on the infection mechanism of Nosema bombycis.展开更多
Recently,some of the genetic mechanisms of heart specification have been elucidated in Drosophila .However,genes involved in early cardiogenesis of human remain to be identified.Since the pathways that regulate ear...Recently,some of the genetic mechanisms of heart specification have been elucidated in Drosophila .However,genes involved in early cardiogenesis of human remain to be identified.Since the pathways that regulate early cardiac fate determination are conserved between Drosophila and vertebrates,flies can be used as a model test system to explore the genetic basis of cardiogenesis in human.In this project,about 3000 reccieve lethal gene lines were produced by P or EMS mutagenesis.With staining of antibodies against heart precussor cells of Drosophila ,about 200 lines were observed to show heart phenotype.In pilot studies of their function with RNAi technique,the RNAi phenotypes of several genes tested were observed,which were very similar to that of their mutants,showing heart tube defects or no heart precursors formation.Taking advantage of the advanced genetic information available in the Drosophila and human systems,we have identified about 50 human transcripts homologous to the Drosophila heart related gene candidates.Northern blot analysis for some of the human candidates showed that several genes were expressed in both adult and early embryonic tissues,which may help in the evaluation of candidate genes for human cardiogenesis.Our further experiments with transgenic flies generated with wild type and mutant forms of these candidate genes to examine for defects in cardiogenesis or cardiac function are under way.The candidate genes producing cardiac specific defects suggestive of similarities to the heart disease syndromes can then be pursued further as likely disease gene candidates.Such an approach is likely to provide a dramatic reduction of possible candidate genes,or to screen and identify mutations that may generate the disease in human.展开更多
Spotted wing drosophila, Drosophila suzukii (Matsumura) (SWD), is emerging as the most significant pest of berries and stone fruits worldwide. With a broad host range, thin-skinned berries are particularly susceptible...Spotted wing drosophila, Drosophila suzukii (Matsumura) (SWD), is emerging as the most significant pest of berries and stone fruits worldwide. With a broad host range, thin-skinned berries are particularly susceptible to infestation, and fruit producers are desperate for methods to control this pest. One of the keys to developing an integrated management program for SWD is to understand host preference and varietal susceptibility of highly susceptible crop hosts. Working in replicated small plots, experiments were conducted to evaluate differences in varietal susceptibility on cold hardy red primocane fruiting raspberries. Significant differences were observed in both the level of infestation and in the average number of larvae per berry by variety. In addition, it appears that there is a significant negative correlation between the level of infestation and the number of larvae per fruit with the time of sampling, but only an interaction of variety and time for the number of larvae per berry. These data provide a better understanding of the biology and ecology of this pest which is critical in refining current management practices. Knowledge of these interactions can aid in optimizing control strategies such as fine-tuning spatial and temporal control measures, which may be particularly important for early season infestations.展开更多
Spotted wing drosophila, <i>Drosophila suzukii</i> (Matsumura) (SWD), is emerging as the most significant pest of berries and stone fruits worldwide. With a broad host range, thin-skinned berries are parti...Spotted wing drosophila, <i>Drosophila suzukii</i> (Matsumura) (SWD), is emerging as the most significant pest of berries and stone fruits worldwide. With a broad host range, thin-skinned berries are particularly susceptible to infestation, and fruit producers are desperate for methods to control this pest. One of the keys to developing an integrated management program for SWD is to understand host preference and varietal susceptibility of highly susceptible crop hosts. Working in replicated small plots, experiments were conducted to evaluate differences in varietal susceptibility on cold hardy red primocane fruiting raspberries. Significant differences were observed in both the level of infestation and in the average number of larvae per berry by variety. In addition, it appears that there is a significant negative correlation between the level of infestation and the number of larvae per fruit with the time of sampling, but only an interaction of variety and time for the number of larvae per berry. These data provide a better understanding of the biology and ecology of this pest which is critical in refining current management practices. Knowledge of these interactions can aid in optimizing control strategies such as fine-tuning spatial and temporal control measures, which may be particularly important for early season infestations.展开更多
We examined mitotic chromosomes of three newly found members of the Drosophila obscura species group,D.luguensis,D.dianensis and D.limingi from Yunnan and compared their karyotypes to those of respective related speci...We examined mitotic chromosomes of three newly found members of the Drosophila obscura species group,D.luguensis,D.dianensis and D.limingi from Yunnan and compared their karyotypes to those of respective related species.D.luguensis possessed a diploid number of 12 chromosomes,comprising 3 pairs of metacentrics (V-shaped),2 pairs of acrocentrics (rod-like) and 1 pair of micro-chromosomes (dot-like).Both the X and Y were metacentrics.D.dianensis and D.limingi possessed a diploid number of 10 chromosomes,comprising 1 pair of large V-shaped,1 pair of moderate-sized V-shaped,2 pairs of submetacentric (J-shaped) chromosomes,and 1 pairs of dot-like chromosomes,with their X chromosomes were J-shaped and Y chromosomes were short rod-like ones.Based upon the results of chromosomal comparisons,geographic information of the sinobscura subgroup,as well inter-specific phylogenetic relationship deduced elsewhere,D.luguensis was considered to retain an ancestral form of the karyotype within this subgroup.The present observations have also implied that D.sinobscura (2n=12:2V,1J,2R,1D) might have derived from a sub-lineage of a pre-“sinobscura-hubeiensis” lineage by pericentric inversion of moderate-sized metacentric autosomes and D.hubeiensis (2n=10:4V,1D) from another sub-lineage of the same lineage by centric fusion of 2 pairs of acrocentric autosomes.Similar chromosomal changes of centric fusion,centric fission and/or pericentric inversion might have occurred during the course of species divergences between D.dianensis and D.subsilvestris (2n=12:3V,2R,1D),an European member closely related to D.dianensis,and between D.limingi and D.tsukubaensis (2n=12:3V,2R,1D),an East Asian member near to D.limingi.展开更多
Both transcription and post-transcriptional processes, such as alternative splicing, play crucial roles in controlling developmental programs in metazoans. Recently emerged RNA-seq method has brought our understanding...Both transcription and post-transcriptional processes, such as alternative splicing, play crucial roles in controlling developmental programs in metazoans. Recently emerged RNA-seq method has brought our understanding of eukaryotic transcriptomes to a new level, because it can resolve both gene expression level and alternative splicing events simultaneously. To gain a better understanding of cellular differentiation in gonads, we analyzed mRNA profiles from Drosophila testes and ovaries using RNA-seq. We identified a set of genes that have sex-specific isoforms in wild-type (WT) gonads, including several transcription factors. We found that differentiation of sperms from undifferentiated germ cells induced a dramatic downregulation of RNA splicing factors. Our data confirmed that RNA splicing events are significantly more frequent in the undifferentiated cell-enriched bag of marbles (barn) mutant testis, but downregulated upon differentiation in WT testis. Consistent with this, we showed that genes required for meiosis and terminal differentiation in WT testis were mainly regulated at the transcriptional level, but not by alternative splicing. Unexpectedly, we observed an increase in expression of all families of chromatin remodeling factors and histone modifying enzymes in the undifferentiated cell-enriched bam testis. More interestingly, chromatin regulators and histone modifying enzymes with opposite enzymatic activities are coenriched in undifferentiated cells in testis, suggesting that these cells may possess dynamic chromatin architecture. Finally, our data revealed many new features of the Drosophila gonadal transcriptomes, and will lead to a more comprehensive understanding of how differential gene expression and splicing regulate gametogenesis in Drosophila. Our data provided a foundation for the systematic study of gene expression and alternative splicing in many interesting areas of germ cell biology in Droso- phila, such as the molecular basis for sexual dimorphism and the regulation of the proliferation vs terminal differentiation programs in germline stem cell lineages. The GEO accession number for the raw and analyzed RNA-seq data is GSE16960.展开更多
基金Key Collaborative Research Program of the Alliance of International Science Organizations(ANSO-CR-KP-2021-12 to L.L.)National Natural Science Foundation of China(32071009,32371063,82341248 to C.L.,31971072 and 32171154 to L.L.)+1 种基金Guangdong Basic and Applied Basic Research Foundation(2024A1515011500 to C.L.)Shenzhen Science Technology and Innovative Commission(SZSTI JCYJ20180508152336419 to L.L.and GJHZ20200731095406021 to S.J.)。
文摘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.
基金supported by the National Natural Science Foundation of China(32072646,31772373,and 32001832).
文摘Ergothioneine is a natural amino acid with powerful antioxidant activity.Previous studies have demonstrated that ergothioneine can increase the lifespan of Drosophila melanogaster and Caenorhabditis elegans,and enhance telomerase activity.In present study,the metagenomics sequencing and quantitative real-time polymerase chain reaction analysis were employed to characterize the composition and diversity of gut microbiome in aging flies.And the alterations in the gut barrier,gut morphology,and other gut physiological indicators of aging flies were evaluated.Here,the results showed that ergothioneine induced little variations in gut microbiota composition in flies at mid-life,and significant alterations in the gut microbiota populations were only observed in flies at late-life.And ergothioneine attenuated age-related gut injuries,including decreasing reactive oxygen species levels in intestinal enterocytes,reduction of intestinal cells death,and preservation of gut integrity in aging flies.Ergothioneine also improved the gut morphology by preserving the structure and shape of cell organelles and inducing the intestinal autophagy.And activation of intestinal autophagy also contributed to the longevity effect mediated by ergothioneine in an unidentified mechanism.
基金supported by the open project of the Key Laboratory of Environmental Pollution Monitoring and Disease Control,Ministry of Education,Guizhou Medical University,China (GMU-2022-HJZ-06)。
文摘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.
基金Supported by Undergraduate Innovation and Entrepreneurship Training Program(202314390006)Undergraduate Innovation and Entrepreneurship Training Program(2024DC078)Construction Project of Biological Experiment Teaching Demonstration Center in Colleges and Universities in Shaanxi Province.
文摘[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.
基金This work was supported by Swiss National Science Foundation,grant#31003A_175658 to VLK.
文摘Neuroscience and neurology research is dominated by experimentation with rodents.Around 75%of neurology disease-associated genes have orthologs in Drosophila mel-anogaster,the fruit fly amenable to complex neurological and behavioral investiga-tions.However,non-vertebrate models including Drosophila have so far been unable to significantly replace mice and rats in this field of studies.One reason for this situ-ation is the predominance of gene overexpression(and gene loss-of-function)meth-odologies used when establishing a Drosophila model of a given neurological disease,a strategy that does not recapitulate accurately enough the genetic disease condi-tions.I argue here the need for a systematic humanization approach,whereby the Drosophila orthologs of human disease genes are replaced with the human sequences.This approach will identify the list of diseases and the underlying genes that can be adequately modeled in the fruit fly.I discuss the neurological disease genes to which this systematic humanization approach should be applied and provide an example of such an application,and consider its importance for subsequent disease modeling and drug discovery in Drosophila.I argue that this paradigm will not only advance our un-derstanding of the molecular etiology of a number of neurological disorders,but will also gradually enable researchers to reduce experimentation using rodent models of multiple neurological diseases and eventually replace these models.
基金supported by the National Natural Science Foundation of China(42006094)by Fujian Natural Science Foundation(2019J05032).
文摘The purpose of this study was to explore the potential of the development and application of Paecilomyces hepiali,a fungus with edible and medicinal value,as a foodborne antioxidant and anti-aging agent.Its n-butanol extract(PHE)from rice cultures was selected for anti-aging experiment because of significant free radical scavenging activity in vitro.In vivo,PHE could significantly prolong the mean lifespan,50%survival days,and the maximum lifespan of Drosophila on a high-fat diet.It is amazing that the mean lifespan increased from 19.1 days to 32.9 days,50%survival days increased from 15.7 days to 34.3 days,and the maximum lifespan extended from 44.7 days to 52.7 days,when the high-fat female Drosophila model was fed with 10μg/mL PHE.Further research showed that PHE reduced the accumulation of peroxide products and increased the activity of antioxidant enzymes.Then,through antioxidant activity tracking,dimerumic acid(compound 1,the IC_(50) value of 3.4μg/mL on DPPH free radicals scavenging activity),4,5-dihydroxy-3-methoxypentanoic acid(compound 2,new compound),and thymidine(compound 3)were isolated from PHE.It is worth mentioning that dimerumic acid,the major antioxidant compound of PHE(content up to 3%),was discovered in P.hepiali for the first time.It was concluded that PHE showed excellent anti-aging activity at a very low concentration on fat diet-induced high fat Drosophila melanogaster,and dimerumic acid may be its main material basis.These results indicated that PHE had the potential to be developed as antioxidant and anti-aging agent in the healthcare industry.
文摘The conditional mutations in drosophila were obtained by γ-irradiation and selected using the test for dominant lethality. The conditional mutations survive under permissive genetic conditions and, additionally, commence to display novel properties. One of such properties is a recessive lethality. Ten conditional mutations that displayed recessive lethality were mapped with the help of a standard set of deletions. Half mutations contained two and more lethal defects. The fact that a large number of the lethal defects are associated with one mutation suggests that γ-irradiation is the most unlikely cause of the defects. One of the conditional mutations carried four lethal regions and had a Small barrel (Smba) visual phenotype. The Smba phenotype in the Smba/ In(2LR) Cy strain is inherited according to a parental type and disappears in the Smba/In(2LR) Pm strain. Lethality in two of the four lethal regions also disappears in this strain. A separate experiment was conducted to clarify how these regions lost a lethal manifestation after the In(2LR) Cy chromosome in the Smba/In(2LR) Cy strain was replaced with the In(2LR) Pm chromosome. The process of disappearance of the Smba phenotype was also observed in three Smba/In(2LR) Cy substocks. These data suggest that the regions of multiple recessive lethality emerge in a secondary manner under the effect of the earlier formed radiation-induced mutation in ontogene. It is assumed that the recessive lethal regions are the ontogenes with an altered DNA conformation. The conformation in ontogenes is changed in the germline cells during a regular “editing” of the individual development program.
基金This work was supported by National Natural Sciences Foundation of China (No. 39930100) International Collaborative Project of Hubei Provincial Department of Education (No. G200610001).
文摘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.
基金Supported by Natural Science Foundation of Chongqing(2008BB1368)~~
文摘[ Objective ] The aim of this study was to investigate the infectivity of Nosema bombycis to drosophila, which offered a new vision for systematical studies on the infection mechanism of Nosema bombycis, and also provided reference for the bio-control effect of Nosema bombycis. [ Method ] Nosema bombycis was used to feed wild type and mutant drosophila, and the morphological observation of Nosema bombycis in drosophila body fluid was also analyzed by calcofluor white M2R fluorescent staining. [ Result] Nosema bombycis could infect drosophila, and the number of Nosema bombycis in the infected mutant drosophila was higher than that in wild type drosophila. [ Conclusion ] Nosema bombycis can infect drosophila, which provides primary reference for studies on the infectivity of Nosema bombycis to other hosts and also lays a foundation for further study on the infection mechanism of Nosema bombycis.
文摘Recently,some of the genetic mechanisms of heart specification have been elucidated in Drosophila .However,genes involved in early cardiogenesis of human remain to be identified.Since the pathways that regulate early cardiac fate determination are conserved between Drosophila and vertebrates,flies can be used as a model test system to explore the genetic basis of cardiogenesis in human.In this project,about 3000 reccieve lethal gene lines were produced by P or EMS mutagenesis.With staining of antibodies against heart precussor cells of Drosophila ,about 200 lines were observed to show heart phenotype.In pilot studies of their function with RNAi technique,the RNAi phenotypes of several genes tested were observed,which were very similar to that of their mutants,showing heart tube defects or no heart precursors formation.Taking advantage of the advanced genetic information available in the Drosophila and human systems,we have identified about 50 human transcripts homologous to the Drosophila heart related gene candidates.Northern blot analysis for some of the human candidates showed that several genes were expressed in both adult and early embryonic tissues,which may help in the evaluation of candidate genes for human cardiogenesis.Our further experiments with transgenic flies generated with wild type and mutant forms of these candidate genes to examine for defects in cardiogenesis or cardiac function are under way.The candidate genes producing cardiac specific defects suggestive of similarities to the heart disease syndromes can then be pursued further as likely disease gene candidates.Such an approach is likely to provide a dramatic reduction of possible candidate genes,or to screen and identify mutations that may generate the disease in human.
文摘Spotted wing drosophila, Drosophila suzukii (Matsumura) (SWD), is emerging as the most significant pest of berries and stone fruits worldwide. With a broad host range, thin-skinned berries are particularly susceptible to infestation, and fruit producers are desperate for methods to control this pest. One of the keys to developing an integrated management program for SWD is to understand host preference and varietal susceptibility of highly susceptible crop hosts. Working in replicated small plots, experiments were conducted to evaluate differences in varietal susceptibility on cold hardy red primocane fruiting raspberries. Significant differences were observed in both the level of infestation and in the average number of larvae per berry by variety. In addition, it appears that there is a significant negative correlation between the level of infestation and the number of larvae per fruit with the time of sampling, but only an interaction of variety and time for the number of larvae per berry. These data provide a better understanding of the biology and ecology of this pest which is critical in refining current management practices. Knowledge of these interactions can aid in optimizing control strategies such as fine-tuning spatial and temporal control measures, which may be particularly important for early season infestations.
文摘Spotted wing drosophila, <i>Drosophila suzukii</i> (Matsumura) (SWD), is emerging as the most significant pest of berries and stone fruits worldwide. With a broad host range, thin-skinned berries are particularly susceptible to infestation, and fruit producers are desperate for methods to control this pest. One of the keys to developing an integrated management program for SWD is to understand host preference and varietal susceptibility of highly susceptible crop hosts. Working in replicated small plots, experiments were conducted to evaluate differences in varietal susceptibility on cold hardy red primocane fruiting raspberries. Significant differences were observed in both the level of infestation and in the average number of larvae per berry by variety. In addition, it appears that there is a significant negative correlation between the level of infestation and the number of larvae per fruit with the time of sampling, but only an interaction of variety and time for the number of larvae per berry. These data provide a better understanding of the biology and ecology of this pest which is critical in refining current management practices. Knowledge of these interactions can aid in optimizing control strategies such as fine-tuning spatial and temporal control measures, which may be particularly important for early season infestations.
文摘We examined mitotic chromosomes of three newly found members of the Drosophila obscura species group,D.luguensis,D.dianensis and D.limingi from Yunnan and compared their karyotypes to those of respective related species.D.luguensis possessed a diploid number of 12 chromosomes,comprising 3 pairs of metacentrics (V-shaped),2 pairs of acrocentrics (rod-like) and 1 pair of micro-chromosomes (dot-like).Both the X and Y were metacentrics.D.dianensis and D.limingi possessed a diploid number of 10 chromosomes,comprising 1 pair of large V-shaped,1 pair of moderate-sized V-shaped,2 pairs of submetacentric (J-shaped) chromosomes,and 1 pairs of dot-like chromosomes,with their X chromosomes were J-shaped and Y chromosomes were short rod-like ones.Based upon the results of chromosomal comparisons,geographic information of the sinobscura subgroup,as well inter-specific phylogenetic relationship deduced elsewhere,D.luguensis was considered to retain an ancestral form of the karyotype within this subgroup.The present observations have also implied that D.sinobscura (2n=12:2V,1J,2R,1D) might have derived from a sub-lineage of a pre-“sinobscura-hubeiensis” lineage by pericentric inversion of moderate-sized metacentric autosomes and D.hubeiensis (2n=10:4V,1D) from another sub-lineage of the same lineage by centric fusion of 2 pairs of acrocentric autosomes.Similar chromosomal changes of centric fusion,centric fission and/or pericentric inversion might have occurred during the course of species divergences between D.dianensis and D.subsilvestris (2n=12:3V,2R,1D),an European member closely related to D.dianensis,and between D.limingi and D.tsukubaensis (2n=12:3V,2R,1D),an East Asian member near to D.limingi.
文摘Both transcription and post-transcriptional processes, such as alternative splicing, play crucial roles in controlling developmental programs in metazoans. Recently emerged RNA-seq method has brought our understanding of eukaryotic transcriptomes to a new level, because it can resolve both gene expression level and alternative splicing events simultaneously. To gain a better understanding of cellular differentiation in gonads, we analyzed mRNA profiles from Drosophila testes and ovaries using RNA-seq. We identified a set of genes that have sex-specific isoforms in wild-type (WT) gonads, including several transcription factors. We found that differentiation of sperms from undifferentiated germ cells induced a dramatic downregulation of RNA splicing factors. Our data confirmed that RNA splicing events are significantly more frequent in the undifferentiated cell-enriched bag of marbles (barn) mutant testis, but downregulated upon differentiation in WT testis. Consistent with this, we showed that genes required for meiosis and terminal differentiation in WT testis were mainly regulated at the transcriptional level, but not by alternative splicing. Unexpectedly, we observed an increase in expression of all families of chromatin remodeling factors and histone modifying enzymes in the undifferentiated cell-enriched bam testis. More interestingly, chromatin regulators and histone modifying enzymes with opposite enzymatic activities are coenriched in undifferentiated cells in testis, suggesting that these cells may possess dynamic chromatin architecture. Finally, our data revealed many new features of the Drosophila gonadal transcriptomes, and will lead to a more comprehensive understanding of how differential gene expression and splicing regulate gametogenesis in Drosophila. Our data provided a foundation for the systematic study of gene expression and alternative splicing in many interesting areas of germ cell biology in Droso- phila, such as the molecular basis for sexual dimorphism and the regulation of the proliferation vs terminal differentiation programs in germline stem cell lineages. The GEO accession number for the raw and analyzed RNA-seq data is GSE16960.