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81.
四个达摩凤蝶新孵幼虫细胞系的建立及其生物学特性 总被引:1,自引:0,他引:1
【目的】建立达摩凤蝶 Papilio demoleus Linnaeus新孵幼虫细胞系,并对其生物学特性进行研究。【方法】使用改良配方的Grace培养基并辅以20%胎牛血清,通过原代和传代培养建立达摩凤蝶新孵幼虫细胞系。通过显微观察、细胞活力分析、核型分析和分子鉴定,获得4个新建细胞系的生物学特性数据。使用Bac-To-Bac杆状病毒表达系统构建重组分泌型碱性磷酸酶杆状病毒(AcMNPV-SEAP)。使用有限稀释法测定达摩凤蝶细胞系对AcMNPV-SEAP的半数组织培养感染剂量(TCID50), 比较达摩凤蝶细胞系对AcMNPV-SEAP的敏感性。【结果】建立了4个贴壁生长的达摩凤蝶新孵幼虫细胞系(RIRI-PaDe-1, RIRI-PaDe-2, RIRI-PaDe-3及RIRI-PaDe-4),且均传至60代以上。形态学方面,细胞系RIRI-PaDe-1和RIRI-PaDe-4较为相近,均由圆形、梭形以及多边形细胞组成,细胞系RIRI-PaDe-2主要为圆形细胞,而RIRI-PaDe-3主要为类似表皮细胞和纤维状细胞。细胞增殖动力学方面,4个细胞系的群体倍增时间分别为69.77, 67.42, 81.48及65.43 h。核型分析显示4个细胞系染色体数量均呈正态分布,其中RIRI-PaDe-2, RIRI-PaDe-3以及RIRI-PaDe-4的染色体数目分布区间比较接近,在45~97条之间,RIRI-PaDe-1的染色体条数相比偏少,在36~90条之间。通过比对4个达摩凤蝶细胞系和虫卵的细胞色素c氧化酶亚基I(COI)基因序列,证明4个新建细胞系来源于达摩凤蝶组织。比较4个细胞系对AcMNPV-SEAP敏感性发现RIRI-PaDe-3对此病毒较为敏感,可作为重组杆状病毒表达的宿主。【结论】虽然4个新建达摩凤蝶细胞系的来源相同,具有相同的遗传背景,但其生物学特征仍有明显差异,具有进一步研究的价值。 相似文献
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银纹夜蛾幼虫 (Argyrogrammaagnata)对松毛虫CPV(DpCPV)十分敏感 ,本文对两种不同的宿主增殖松毛虫CPV作了比较 ,电镜证实用替代宿主增殖的DpCPV与原毒株多角体 (CPB)和病毒粒子的形态完全一致。 3 %PAGE分析二者的RNA图谱基本一致 ,有大小相同的 2 .98× 10 6- 0 .6 6× 10 6道尔顿的 10条带 ,用它增殖的DpCPV(Aa DpCPV)对松毛虫有相当的毒力 ,每头 3龄幼虫病毒产量平均为 2 .5× 10 8CPB。 相似文献
84.
Since the discovery of adult neurogenesis, a major issue is the role of newborn neurons and the function-dependent regulation of adult neurogenesis. We decided to use an animal model with a relatively simple brain to address these questions. In the adult cricket brain as in mammals, new neurons are produced throughout life. This neurogenesis occurs in the main integrative centers of the insect brain, the mushroom bodies (MBs), where the neuroblasts responsible for their formation persist after the imaginal molt. The rate of production of new neurons is controlled not only by internal cues such as morphogenetic hormones but also by external environmental cues. Adult crickets reared in an enriched sensory environment experienced an increase in neuroblast proliferation as compared with crickets reared in an impoverished environment. In addition, unilateral sensory deprivation led to reduced neurogenesis in the MB ipsilateral to the lesion. In search of a functional role for the new cells, we specifically ablated MB neuroblasts in young adults using brain-focused gamma ray irradiation. We developed a learning paradigm adapted to the cricket, which we call the "escape paradigm." Using this operant associative learning test, we showed that crickets lacking neurogenesis exhibited delayed learning and reduced memory retention of the task when olfactory cues were used. Our results suggest that environmental cues are able to influence adult neurogenesis and that, in turn, newly generated neurons participate in olfactory integration, optimizing learning abilities of the animal, and thus its adaptation to its environment. Nevertheless, odor learning in adult insects cannot always be attributed to newly born neurons because neurogenesis is completed earlier in development in many insect species. In addition, many of the irradiated crickets performed significantly better than chance on the operant learning task. 相似文献
85.
The mountain pine beetle Dendroctonus ponderosae Hopkins is a major native pest of Pinus Linnaeus (Pinaceae) in western North America. Host colonization by the mountain pine beetle is associated with an obligatory dispersal phase, during which beetles fly in search of a suitable host. Mountain pine beetles use stored energy from feeding in the natal habitat to power flight before host colonization and brood production. Lipids fuel mountain pine beetle flight, although it is not known whether other energy sources are also used during flight. In the present study, we compare the level of energy substrates, proteins, carbohydrates and lipids of individual mountain pine beetles flown on flight mills with unflown control beetles. We use a colorimetric method to measure the entire metabolite content of each individual beetle. The present study reveals that mountain pine beetles are composed of more protein and lipid than carbohydrate. Both female and male mountain pine beetles use lipids and carbohydrates as energy sources during flight. There is variation between sexes, however, in the energy substrates used for flight. Male mountain pine beetles use protein, in addition to lipids and carbohydrates, to fuel flight, whereas protein content is not different between flown and control females. 相似文献
86.
Angela M. Mech Kathryn A. Thomas Travis D. Marsico Daniel A. Herms Craig R. Allen Matthew P. Ayres Kamal J. K. Gandhi Jessica Gurevitch Nathan P. Havill Ruth A. Hufbauer Andrew M. Liebhold Kenneth F. Raffa Ashley N. Schulz Daniel R. Uden Patrick C. Tobin 《Ecology and evolution》2019,9(21):12216-12230
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87.
Erica H. Odell Nigel E. Stork Roger L. Kitching 《Biological reviews of the Cambridge Philosophical Society》2019,94(4):1416-1429
Woody climbers or, ‘lianas’, are one of the features that characterise rainforests. They contribute substantially to plant diversity and leaf biomass which makes them a potentially important food source for herbivores. Here, we focus on insect herbivores, folivores in particular, to show how disparities in the quantitative and qualitative availability of leaves between lianas and trees may differentially influence insect folivory and the herbivore communities themselves. We develop a conceptual model and show that lianas in general have lower structural and chemical defences, a greater nutritional profile and a preferable phenology in comparison with trees, which, contrary to our expectations, has led to assemblages of more‐specialised insects. The impacts this has on higher trophic levels and broader ecological networks, however, are poorly known. We show through a study of four tropical floras from different biogeographic realms that lianas are likely to be a target for a wide range of insect herbivore taxa as they are a phylogenetically diverse group and increase diversity of higher taxa at local scales. This, in combination with their highly palatable leaves, may also make them a suitable temporary food source for insects during times when preferred host plants are scarce. This phenomenon has been observed in mammalian herbivores but awaits investigation in insects as does the effects this may have on survival and fitness. Apparent recent increases in liana abundances in some forests, likely due to climate change, makes understanding their role in supporting and maintaining biodiversity an increasingly important and necessary challenge. Since trees or saplings have usually been the subject of studies on insect herbivory, major knowledge gaps remain about the ways in which lianas contribute to, support and maintain the ecosystems in which they exist. We use our conceptual model to guide future research directions and express the necessity for caution when extrapolating explanations of herbivory derived from data on trees to growth forms with fundamentally different ecologies. 相似文献
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89.
昆虫抗菌肽及其基因工程研究进展 总被引:12,自引:0,他引:12
昆虫抗菌肽是昆虫免疫后存在于血淋巴中的一类活性肽,具有广谱的抗菌、抗病毒、抑制肿瘤的生物活性,具有很高的应用潜力。本文主要介绍昆虫抗菌肽的类型、生理活性、基因的克隆与表达及转基因工程研究进展。
Insect Antibacterial Peptides and Its Progress in Advance on Genetic Engineering
GONG Xia,YUE Guo-wei,SHI Yong-hui
Laboratory for Animal Nutrition Research,College of Food Science,Southern Yangtze University,Wuxi 214036,China
Abstract:Insect antibacterial peptides produced are kinds of bioactive peptides in hameolymph hen insect has been immunized.These peptides have the wide range of antibacterial,antiviral spectrum and inhibiting growth of tumor cell.The types of antibacterial peptides and its physiological activities,cloning and expression of the genes and transgenetic research are summarized.Its application on medicine and gene engineering are prospected.
Key words:insect antibacterial peptides; physiological activity; gene 相似文献
90.