The immune interactions occurring between parasitoids and their host insects,especially in Drosophila-wasp models,have long been the research focus of insect immunology and parasitology.Parasitoid infestation in Droso...The immune interactions occurring between parasitoids and their host insects,especially in Drosophila-wasp models,have long been the research focus of insect immunology and parasitology.Parasitoid infestation in Drosophila is counteracted by its multiple natural immune defense systems,which include cellular and humoral immunity,Occurring in the hemocoel,cellular immune responses involve the proliferation,differentiation,migration and spreading of host hemocytes and parasitoid encapsulation by them.Contrastingly,humoral immune responses rely more heavily on melanization and on the Toll,Imd and Jak/Stat immune pathways associated w ith antimicrobial peptides along with stress factors.On the wasps'side,successful development is achieved by introducing various virulence factors to counteract immune responses of Drosophila.Some or all of these factors manipulate the host's immunity for successful parasitism.Here we review current knowledge of the cellular and humoral immune interactions between Drosophila and its parasitoids,focusing on the defense mechanisms used by Drosophila and the strategies evolved by parasitic wasps to outwit it.展开更多
Technology development has always been one of the forces driving breakthroughs in biomedical research. Since the time of Thomas Morgan, Drosophilists have, step by step, developed powerful genetic tools for manipulati...Technology development has always been one of the forces driving breakthroughs in biomedical research. Since the time of Thomas Morgan, Drosophilists have, step by step, developed powerful genetic tools for manipulating and functionally dissecting the Drosophila genome, but room for improving these technologies and developing new techniques is still large, especially today as biologists start to study systematically the functional genomics of different model organisms, including humans, in a high-throughput manner. Here, we report, for the first time in Drosophila, a rapid, easy, and highly specific method for modifying the Drosophila genome at a very high efficiency by means of an improved transcription activator-like effector nuclease （TALEN） strategy. We took advantage of the very recently developed ＂unit assembly＂ strategy to assemble two pairs of specific TALENs designed to modify the yellow gene （on the sex chromosome） and a novel autosomal gene. The mRNAs of TALENs were subsequently injected into Drosophila embryos. From 31.2% of the injected Fo fertile flies, we detected inheritable modification involving the yellow gene. The entire process from construction of specific TALENs to detection of inheritable modifications can be accomplished within one month. The potential applications of this TALEN-mediated genome modification method in Drosophila are discussed.展开更多
Achyranthes bidentata polysaccharides (ABPS), water_soluble polysaccharides, isolated from the roots of Achyranthes bidentata Bl. of Amaranthaceae family, was divided into four parts, named as Con.1, Con.2, Con....Achyranthes bidentata polysaccharides (ABPS), water_soluble polysaccharides, isolated from the roots of Achyranthes bidentata Bl. of Amaranthaceae family, was divided into four parts, named as Con.1, Con.2, Con.3 and Con.4, respectively, by chromatography on DEAE_Sepharose fast_flow column and Sephadex G_100 column in order. Con.1 was the constituent of high molecular weight and the other three were all of low molecular weight. Micro_Kjeldahl analysis showed that Con.1 contained 3.95% of nitrogen and neither did the other three parts. The antisenile effects of the four parts of ABPS were studied with Drosophila melanogaster. Results showed that Con.1 has no antisenile effect and all the others could significantly increase the average body weight by 3.85%-5.47% and significantly prolonged the average lifespan by 2.61%- 3.16% of D. melanogaster at the concentration of 2 or 5 mg/g (ABPS/medium).展开更多
The innate immune system of insects is divided into humoral defenses that include the production of soluble effector molecules and cellular defenses like phagocytosis and encapsulation that are mediated by hemocytes. ...The innate immune system of insects is divided into humoral defenses that include the production of soluble effector molecules and cellular defenses like phagocytosis and encapsulation that are mediated by hemocytes. This review summarizes current understand- ing of the cellular immune response. Insects produce several terminally differentiated types of hemocytes that are distinguished by morphology, molecular and antigenic markers, and function. The differentiated hemocytes that circulate in larval or nymphal stage insects arise from two sources： progenitor cells produced during embryogenesis and mesodermally derived hematopoietic organs. Regulation of hematopoiesis and hemocyte differentiation also involves several different signaling pathways. Phagocytosis and encapsulation require that hemocytes first recognize a given target as foreign followed by activation of downstream signaling and effector responses. A number of humoral and cellular receptors have been identified that recognize different microbes and multicellular parasites. In turn, activation of these receptors stimulates a number of signaling pathways that regulate different hemocyte functions. Recent studies also identify hemocytes as important sources Of a number of humoral effector molecules required for killing different foreign invaders.展开更多
Recent advances in our ability to design DNA binding factors with specificity for desired sequences have resulted in a revolution in genetic engineering, enabling directed changes to the genome to be made relatively e...Recent advances in our ability to design DNA binding factors with specificity for desired sequences have resulted in a revolution in genetic engineering, enabling directed changes to the genome to be made relatively easily. Traditional techniques for generating genetic mutations in most organisms have relied on selection from large pools of randomly induced mutations for those of particular interest, or time-consuming gene targeting by homologous recombination. Drosophila melanogaster has always been at the forefront of genetic analysis, and application of these new genome editing techniques to this organism will revolutionise our approach to performing analysis of gene function in the future. We discuss the recent techniques that apply the CRISPR/Cas9 system to Drosophila, highlight potential uses for this technology and speculate upon the future of genome engineering in this model organism.展开更多
Compartmentation is essential for the localization of biological processes within a eukaryotic cell. ATP synthase localizes to organelles such as mitochondria and chloroplasts. By contrast, little is known about the s...Compartmentation is essential for the localization of biological processes within a eukaryotic cell. ATP synthase localizes to organelles such as mitochondria and chloroplasts. By contrast, little is known about the subcellular distribution of CTP synthase, the critical enzyme in the production of CTP, a high-energy molecule similar to ATP. Here I describe the identification of a novel intracellular structure con- taining CTP synthase, termed the cytoophidium, in Drosophila cells. I find that cytoophidia are present in all major cell types in the ovary and exist in a wide range of tissues such as brain, gut, trachea, testis, accessory gland, salivary gland and lymph gland. In addition, I find CTP synthase-containing cytoophidia in other fruit fly species. The observation of compartmentation of CTP synthase now permits a broad range of questions to be addressed concerning not only the structure and function of cytoophidia but also the organization and regulation of CTP synthesis.展开更多
基金the Key Program of Na-tional Natural Science Foundation of China(31830074)the Major International(Regional)Joint Research Project of NSFC(31620103915)+1 种基金the Program for Chinese Inno-vation Team in Key Areas of Science and Technology of the Ministry of Science and Technology of the People's Republic of China(2016RA4008)the Program for Chinese Outstanding Talents in Agricultural Scientific Research of the Ministry of Agriculture and Rural Af-fairs of the People's Republic of China.
文摘The immune interactions occurring between parasitoids and their host insects,especially in Drosophila-wasp models,have long been the research focus of insect immunology and parasitology.Parasitoid infestation in Drosophila is counteracted by its multiple natural immune defense systems,which include cellular and humoral immunity,Occurring in the hemocoel,cellular immune responses involve the proliferation,differentiation,migration and spreading of host hemocytes and parasitoid encapsulation by them.Contrastingly,humoral immune responses rely more heavily on melanization and on the Toll,Imd and Jak/Stat immune pathways associated w ith antimicrobial peptides along with stress factors.On the wasps'side,successful development is achieved by introducing various virulence factors to counteract immune responses of Drosophila.Some or all of these factors manipulate the host's immunity for successful parasitism.Here we review current knowledge of the cellular and humoral immune interactions between Drosophila and its parasitoids,focusing on the defense mechanisms used by Drosophila and the strategies evolved by parasitic wasps to outwit it.
基金supported by the grants from the 973 Program(Nos.2009CB918702 and 2012CB945101)the NSFC(Nos.31071087 and 31100889)+1 种基金W.-M.D.is supported by NIH grant R01GM072562National Science Foundation of USA(IOS-1052333)
文摘Technology development has always been one of the forces driving breakthroughs in biomedical research. Since the time of Thomas Morgan, Drosophilists have, step by step, developed powerful genetic tools for manipulating and functionally dissecting the Drosophila genome, but room for improving these technologies and developing new techniques is still large, especially today as biologists start to study systematically the functional genomics of different model organisms, including humans, in a high-throughput manner. Here, we report, for the first time in Drosophila, a rapid, easy, and highly specific method for modifying the Drosophila genome at a very high efficiency by means of an improved transcription activator-like effector nuclease （TALEN） strategy. We took advantage of the very recently developed ＂unit assembly＂ strategy to assemble two pairs of specific TALENs designed to modify the yellow gene （on the sex chromosome） and a novel autosomal gene. The mRNAs of TALENs were subsequently injected into Drosophila embryos. From 31.2% of the injected Fo fertile flies, we detected inheritable modification involving the yellow gene. The entire process from construction of specific TALENs to detection of inheritable modifications can be accomplished within one month. The potential applications of this TALEN-mediated genome modification method in Drosophila are discussed.
文摘Achyranthes bidentata polysaccharides (ABPS), water_soluble polysaccharides, isolated from the roots of Achyranthes bidentata Bl. of Amaranthaceae family, was divided into four parts, named as Con.1, Con.2, Con.3 and Con.4, respectively, by chromatography on DEAE_Sepharose fast_flow column and Sephadex G_100 column in order. Con.1 was the constituent of high molecular weight and the other three were all of low molecular weight. Micro_Kjeldahl analysis showed that Con.1 contained 3.95% of nitrogen and neither did the other three parts. The antisenile effects of the four parts of ABPS were studied with Drosophila melanogaster. Results showed that Con.1 has no antisenile effect and all the others could significantly increase the average body weight by 3.85%-5.47% and significantly prolonged the average lifespan by 2.61%- 3.16% of D. melanogaster at the concentration of 2 or 5 mg/g (ABPS/medium).
文摘The innate immune system of insects is divided into humoral defenses that include the production of soluble effector molecules and cellular defenses like phagocytosis and encapsulation that are mediated by hemocytes. This review summarizes current understand- ing of the cellular immune response. Insects produce several terminally differentiated types of hemocytes that are distinguished by morphology, molecular and antigenic markers, and function. The differentiated hemocytes that circulate in larval or nymphal stage insects arise from two sources： progenitor cells produced during embryogenesis and mesodermally derived hematopoietic organs. Regulation of hematopoiesis and hemocyte differentiation also involves several different signaling pathways. Phagocytosis and encapsulation require that hemocytes first recognize a given target as foreign followed by activation of downstream signaling and effector responses. A number of humoral and cellular receptors have been identified that recognize different microbes and multicellular parasites. In turn, activation of these receptors stimulates a number of signaling pathways that regulate different hemocyte functions. Recent studies also identify hemocytes as important sources Of a number of humoral effector molecules required for killing different foreign invaders.
基金supported by the UK Medical Research Council and the European Research Council (DARCGENs, No. 249869)
文摘Recent advances in our ability to design DNA binding factors with specificity for desired sequences have resulted in a revolution in genetic engineering, enabling directed changes to the genome to be made relatively easily. Traditional techniques for generating genetic mutations in most organisms have relied on selection from large pools of randomly induced mutations for those of particular interest, or time-consuming gene targeting by homologous recombination. Drosophila melanogaster has always been at the forefront of genetic analysis, and application of these new genome editing techniques to this organism will revolutionise our approach to performing analysis of gene function in the future. We discuss the recent techniques that apply the CRISPR/Cas9 system to Drosophila, highlight potential uses for this technology and speculate upon the future of genome engineering in this model organism.
文摘Compartmentation is essential for the localization of biological processes within a eukaryotic cell. ATP synthase localizes to organelles such as mitochondria and chloroplasts. By contrast, little is known about the subcellular distribution of CTP synthase, the critical enzyme in the production of CTP, a high-energy molecule similar to ATP. Here I describe the identification of a novel intracellular structure con- taining CTP synthase, termed the cytoophidium, in Drosophila cells. I find that cytoophidia are present in all major cell types in the ovary and exist in a wide range of tissues such as brain, gut, trachea, testis, accessory gland, salivary gland and lymph gland. In addition, I find CTP synthase-containing cytoophidia in other fruit fly species. The observation of compartmentation of CTP synthase now permits a broad range of questions to be addressed concerning not only the structure and function of cytoophidia but also the organization and regulation of CTP synthesis.
