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61.
Olfaction is essential for regulating the physiological and behavioral actions of insects with specific recognition of various odors. Antheraea moths (Lepidoptera: Saturniidae) possess relatively large bodies and antennae so that they are good subjects for exploring molecular aspects of insect olfaction. Current knowledge of the molecular aspects of Antheraea olfaction is focused on the Chinese tussah silkmoth A. pernyi Guérin-Méneville and another species A. polyphemus (Cramer) in their pheromones, odorant-binding proteins (OBPs), odorant receptors (ORs), odorant receptor coreceptors (ORCOs), sensory neuron membrane proteins (SNMPs), and odorant-degrading enzymes (ODEs). The first insect OBP, SNMP, and ODE were identified from A. polyphemus. This review summarizes the principal findings associated with the olfactory physiology and its molecular components in the two Antheraea species. Three types of olfactory neurons may have specific ORs for three respective sex-pheromone components, with the functional sensitivity and specificity mediated by three respective OBPs. SNMPs and ODEs are likely to play important roles in sex-pheromone detection, inactivation, and degradation. Identification and functional analysis of the olfactory molecules remain to be further performed in A. pernyi, A. polyphemus, and other Antheraea species.  相似文献   
62.
Electrophysiological parameters were measured at different temperatures in resting and pheromone-stimulated olfactory sensilla trichodea of male Antheraea polyphemus (Saturniidae). A method for selective cooling of either the olfactory hair or the antennal branch was developed.The resting preparation resistance increased with lower temperatures, the transepithelial potential decreased. These effects were also observed when the antennal branch was cooled, but were absent during cooling the hair, suggesting a major influence of auxiliary cells on the transepithelial potential and resistance. Together with the preparation resistance, the responses to pheromone stimuli increased with lower temperatures.Computer simulation of the current flow in the sensillum showed that the temperature dependence of responses to pheromone can be explained by modulation of resting resistances of cell membranes alone, without effects of temperature on stimulus transduction. The weak temperature dependence of transepithelial potential might be due to temperature dependence of the electrogenic pump producing the transepithelial potential.Selective cooling of the olfactory hair had no effect on the shape of nerve impulses, cooling of the antennal branch caused changes similar to that obtained by cooling the entire sensillum. This supports the idea that the nerve impulses are generated in the soma of the receptor cell.Abbreviations R prep preparation resistance - R prep reduction of R prep during chemical stimulation - TEP transepithelial potential - TEP receptor-potential amplitude - t hd half-time of decline of the receptor potential - t hr half-time of rise of the receptor potential  相似文献   
63.
高温对珍贵绢丝昆虫——天蚕卵巢生长发育的影响   总被引:5,自引:0,他引:5  
叶恭银  胡萃  龚和 《生态学报》2000,20(3):490-494
结果表明,高温对天蚕(Antheraea yamamai)卵巢生长发育有明显的影响。3、4龄幼虫卵巢生长发育在20 ̄29℃范围内随温度提高而加快,32℃下则略有下降;5龄幼虫卵巢生长发育在29℃和32℃下明显受阻。在茧蛹期,若在刚结茧或化蛹第1天即经受32℃高温处理,卵巢大小及其可溶性蛋白含量多明显小于或低于26℃,即其卵巢生长发育明显受阻;而在化蛹第6天开始受32℃高温处理,结果则似反之。正因为  相似文献   
64.
65.
在蛹化第一天的卵巢管中一可见卵母细胞已经分化.但大小和滋养细胞接近。到第三天,卵母细胞体积明星增大,细胞核大而清新,滋养细胞排列趋于规则.滤胞细胞仍为合胞体.分布于卵巢管的周围,以后,滤胞细胞分化,卵母细胞开始摄取卵黄蛋白,并随着卵黄沉积而增大,滋养细胞逐新缩小消失。从卵母细胞纯化出卵黄磷蛋白并制备抗血清.对卵黄磷蛋白的摄入进行了研究,观察到卵黄磷蛋白是由滤胞细胞间隙经滤细胞膜主动运输进入卵母细胞的。  相似文献   
66.
柞蚕核型多角体病毒(AnpeNPV)作为基因表达载体在柞蚕培养细胞(AnPe细胞)和柞蚕蛹中已经成功地表达出了外来基因,并生产出了大量蛋白质。本文比较了AnpeNPV与苜蓿尺蠖核型多角体病毒(AcMNPV)、家蚕核型多角体病毒(BmNPV)和美国白蛾核型多角体病毒(HycuNPV)基因表达载体在培养细胞和昆虫活体组织内的β-半乳糖苷酶基因表达效果。结果显示,5×105个细胞中β-半乳糖苷酶的最高酶活性分别是AnpeNPV在AnPe细胞为40.9 units/ml (TC-100培养液,FBS10%)和59.9 units/ml(SF-900Ⅱ培养液),AcMNPV在Sf9细胞为72.4 units/ml(TC-100,FBS10%)和66.4 units/ml(SF-900Ⅱ)、在High5细胞为326 units/ml(EX-CELL 405培养液),BmNPV在Bm4细胞为15.1 units/ml(TC-100,FBS10%),HycuNPV在SpIm细胞为68.6 units/ml(SF-900Ⅱ)。活体组织内β-半乳糖苷酶的最高酶活性分别是柞蚕雌蛹为14.3 units/g、雄蛹为11.7 units/g,家蚕幼虫是10.1 units/g。实验证明AnpeNPV/AnPe的外来基因表达水平与AcMNPV/ Sf9和HycuNPV/SpIm相似、比BmNPV/ Bm4高、不及AcMNPV/ High5;AnpeNPV/柞蚕蛹,其雌蛹比BmNPV/家蚕5龄幼虫的外来基因表达效果好、雄蛹与之无明显差异,说明AnpeNPV基因表达载体无论是在培养细胞还是昆虫活体组织中均可与其他NPV基因表达载体相媲美。柞蚕蛹由于可以机械化、大规模地操作,显示对于大量生产蛋白质具有更好的应用前景。  相似文献   
67.
ABSTRACT As quality of forested habitat declines from altered fire regimes, gopher tortoises (Gopherus polyphemus) often move into ruderal areas to the detriment of the animal and land manager. We evaluated effects of a dormant-and-growing-season prescribed fire on habitat and gopher tortoise use of degraded longleaf pine (Pinus palustris) forests surrounding military training areas. We burned 4 of 8 sites in winter 2001–2002 and again in April 2003. Changes in vegetation measured during 2001–2004 indicated that burn treatments did not increase herbaceous vegetation. Similarly, movement patterns, burrow usage, and home range of tortoises radiotracked from 2002–2004 did not differ between treatments. Woody cover initially was reduced in the forests postburn, and we found more new burrows in burned forest sites. Once shrub cover was reduced, tortoises started using forested habitat that had become overgrown. However, shrub reduction may be temporary, as woody stem densities increased postburn. Thus, the one-time use of fire to manage tortoise habitat may not rapidly restore the open canopy, sparse woody midstory, and abundant herbaceous vegetation that this species requires. Repeated prescribed fires or additional management techniques may be needed for complete restoration.  相似文献   
68.
The distribution of odorant-binding proteins among olfactory sensilla of three moth species was studied by immuno-electron microscopy. Two polyclonal antisera were used in a post-embedding labelling protocol on sections of cryo-substituted antennae. The first was directed against the pheromone-binding protein (PBP) of Antheraea polyphemus, the second against the general odorant-binding protein (GOBP) of the same species. Immunoblots showed that these antisera were highly specific; both antisera did, however, cross-react with related proteins in the related species A. pernyi, and in the bombycid moth B. mori. PBP and GOBP were localized only in olfactory sensilla trichodea and sensilla basiconica, the principal site being the sensillum lymph surrounding the sensory dendrites. In the males of all three species, the pheromone-sensitive long sensilla trichodea exclusively contained PBP. the majority of the sensilla basiconica in both sexes in these species contained GOBP; these sensilla are known to respond to plant and other general odours. Some sensilla were not labelled by either antiserum; presumably, these held an odorantbinding protein of a different subfamily. Never were PBP and GOBP co-localized in the same sensillum. Two observations deserve special attention: (1) PBP was also found in a few sensilla in females, and (2) in B. mori, where the long sensilla trichodea have a different functional specificity in males (pheromone) and females (plant odours), the expression of the odorant-binding protein (males: PBP; females: GOBP) is similarly different. The distinct and complex distribution pattern of odorant-binding proteins supports the notion that these proteins participate in stimulus recognition.Dedicated to Professor Ya.A. Vinnikov on the occasion of his 85. birthdayThis work was partly supported by DFG grant ste 501/3-1.  相似文献   
69.
比较了不同诱导源对诱导柞蚕蛹血淋巴中抗菌活力的动力学变化。各种化学试剂包括生理盐水都能诱导产生抗菌物质。在不引起死亡的刺激量下,刺激量愈大,诱导的抗菌活力愈高。不同金属络合剂所诱导产生的抗菌物质组份可有很大区别。如二氮杂菲使P_(9E)及P_(9A)的组份比例增高,而EDTA则可提高P_(9B)及P_(9D)组份的比例。P_(9E)和P_(9A),P_(9D)和P_(9B)的产生分别有对应关系,讨论了是否由两个不同基因所控制。 大肠杆菌诱导后的柞蚕蛹,除在血淋巴中测得抗菌活力,在雌雄的生殖腺内含物中也能测得。摘除生殖腺后虽然在血淋巴中仍能诱导出抗菌物质,但应答较慢,活力也较小,也可能由于手术创伤较大,同样的刺激量容易引起死亡。  相似文献   
70.
柞蚕微孢子虫孢子分离纯化方法   总被引:7,自引:0,他引:7  
柞蚕微粒子病是柞蚕Antheraea pernyi(Guérin-Méneville)的主要胚胎传染性病害,病原为柞蚕微孢子虫Nosema pernyi(Wenet Ding),其病原分离提纯技术研究对于柞蚕微粒子病的防治具有重要意义。本文利用差速离心和Percoll密度梯度离心法研究了柞蚕微孢子虫孢子的分离纯化方法,结果表明,采用不连续密度梯度分离纯化柞蚕微孢子虫孢子的效果比单一浓度的效果好,以浓度为25%、50%、75%、100%不连续梯度,15000r/min离心30min分离纯化得到的柞蚕微孢子虫孢子纯净度高。  相似文献   
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