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A M Handler  R A Harrell 《BioTechniques》2001,31(4):820, 824-820, 828
Genetic transformation of most insect systems requires dominant-acting markers that do not depend on reverting a mutant phenotype in a host strain, andfor this purpose GFP has proven to be useful in several insect orders. However, detection of multiple transgenes and reporters for gene expression requires the development of new visible markers that can be unambiguously detected when co-expressed with GFP The DsRed fluorescentprotein has spectral characteristics that are most distinct from GFP and GFP variants, and we have explored the use of DsRed as a selectable marker for piggyBac transformation in Drosophila melanogaster and its use as a reporter when co-expressed with GFP. Transformants marked with polyubiquitin-regulated DsRed1 were detected throughout development at a relatively high frequency, and they exhibited brighter fluorescence than transformants marked with EGFP. The use of a Texas Red filter set eliminated detection of EGFP fluorescence and autofluorescence, and DsRed expressedfrom a reporter construct could be unambiguously detected when co-expressed with EGFP DsRed should prove to be a highly efficient marker system for the selection of transformant insects and as a reporter in gene expression studies.  相似文献   

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B Czeczuga 《Folia biologica》1991,39(1-4):17-20
The presence of carotenoids in Catopus tritis infernus Szymanowski 1957 and Choleva lederiana gracilenta Szymanowski 1957 from a cave was studies, using columnar and thin-layer chromatography. Qualitative and quantitative differences in the carotenoid content of these insect species were found.  相似文献   

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@9cIntroduction@21T issues exhibit an impressive ability to respond to a myriad of insults by repairing and regenerating complex structures. The elegant and orderly process of regeneration provides clues to the mechanisms of pattern formation but also offers the hope that the process might one day be manipulated to replace damaged body parts. To manipulate the process, it will be necessary to understand the genetic basis of the process. In the case of the insect leg, we are coming close to such a level of understanding and many of the lessons learned are relevant to vertebrate systems. A dynamic web of gene regulatory networks appears to create a robust self-organizing system that is at once extremely intricate but also perhaps simple in its reliance on a few key signaling pathways and a few simple processes, e.g. autoactivation and lateral inhibition. Here we will summarize what has been learned about the networks of gene regulation present in the Drosophila leg discs and then we will explore how the regenerative responses to different insults can be understood as predictable responses to these networks. Each of the regulatory networks could themselves serve as the subject of a detailed review and that is beyond the scope of this discussion. Here we will focus on the interplay between the regulatory networks in patterning the tissue.  相似文献   

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携播螨与昆虫   总被引:1,自引:0,他引:1  
文中指明了螨和昆虫之间的携播现象以及携播螨的特点 ,并讨论了螨和昆虫之间的携播现象与人类的关系。  相似文献   

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昆虫的体外化学防卫物质简介   总被引:4,自引:0,他引:4  
本文介绍了昆虫体外防御物质的释放部位、来源、化学成分及影响其释放的因素等的研究进展。  相似文献   

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Antibacterial peptides isolated from insects.   总被引:17,自引:0,他引:17  
Insects are amazingly resistant to bacterial infections. To combat pathogens, insects rely on cellular and humoral mechanisms, innate immunity being dominant in the latter category. Upon detection of bacteria, a complex genetic cascade is activated, which ultimately results in the synthesis of a battery of antibacterial peptides and their release into the haemolymph. The peptides are usually basic in character and are composed of 20-40 amino acid residues, although some smaller proteins are also included in the antimicrobial repertoire. While the proline-rich peptides and the glycine-rich peptides are predominantly active against Gram-negative strains, the defensins selectively kill Gram-positive bacteria and the cecropins are active against both types. The insect antibacterial peptides are very potent: their IC50 (50% of the bacterial growth inhibition) hovers in the submicromolar or low micromolar range. The majority of the peptides act through disintegrating the bacterial membrane or interfering with membrane assembly, with the exception of drosocin, apidaecin and pyrrhocoricin which appear to deactivate a bacterial protein in a stereospecific manner. In accordance with their biological function, the membrane-active peptides form ordered structures, e.g. alpha-helices or beta-pleated sheets and often cast permeable ion-pores. Their cytotoxic properties were exploited in in vivo studies targeting tumour progression. Although the native peptides degrade quickly in biological fluids other than insect haemolymph, structural modifications render the peptides resistant against proteases without sacrificing biological activity. Indeed, a pyrrhocoricin analogue shows lack of toxicity in vitro and in vivo and protects mice against experimental Escherichia coli infection. Careful selection of lead molecules based on the insect antibacterial peptides may extend their utility and produce viable alternatives to the conventional antimicrobial compounds for mammalian therapy.  相似文献   

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严莹  李恺  杨辉 《昆虫知识》2010,47(6):1287-1293
在通常的城市绿地系统规划中,植物类型的选择和配置一般仅考虑其改善生态环境方面的效应。不同的植物群落上生活着不同的昆虫群落。在昆虫群落中,观赏性昆虫,譬如蝴蝶、蟋蟀和萤火虫等,则可作为一种新兴的生态景观应用于绿化中,可形成动态的景观。本文通过对崇明地区的观赏性昆虫类群调查及其与植物关系的理论分析,提出了适合崇明地区的观赏性昆虫造景方案,提供了营建生态小区的新思路。  相似文献   

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The conditions of phospholipase C (EC 3.1.4.3) production by a strain ofBacillus cereus and a method of its preparation are described. The molecular weight of the enzyme as determined by gel filtration is 24,000. Comparison of several characteristics of the enzyme (pH optimum, immunospecificity, mobility in discelectrophoresis) with that fromClostridium perfringens shows them to be different molecules.  相似文献   

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Acidified 2,2-dimethoxypropane (DMP), used as an alternative to regular fixation and dehydration methods for insects, was found to be the only successful means of preparing the sugarbeet root maggot larva, Tetanops myopaeformis (R?der) (Diptera:Otitidae), for the scanning electron microscope. No morphological changes were evident when DMP treated sugarbeet root maggot adults were compared to fresh (unfixed) adults and glutaraldehyde-osmium tetroxide fixed adults. The method has been used with success on several gropus of insects. Acidified CMP is quickly hydrolyzed by water in tissue to acetone and methanol. DMP is advantageous in that it penetrates water impermeable cuticles rapidly and saves several steps and time in the fixation and dehydration process.  相似文献   

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The probit 9 standard for quarantine treatment efficacy (99.9968% mortality) was originally recommended for tropical fruits heavily infested with fruit flies and it centers on high mortality to achieve quarantine security. This standard may be too stringent for quarantine pests in commodities that are rarely infested or are poor hosts, The alternative treatment efficacy approach measures risk as the probability of a mating pair, gravid female, or parthenogenic individual surviving in a shipment. This will be a function of many factors including infestation rate and shipment volume. Applying the risk-based alternative treatment efficacy approach to pests on rarely infested or poor hosts will lower the number of required test insects needed for developing quarantine treatments; hence data for a quarantine treatment could be generated by testing 10,000 or fewer insects with no survivors, compared with 90,000-100,000 insects to demonstrate the traditional probit 9 efficacy. Several commodity/quarantine pest systems where this approach could be applied are discussed. This approach would save time and resources, and help farmers export their crop on a more-timely basis.  相似文献   

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