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鱼类微孢子虫的研究进展 总被引:1,自引:0,他引:1
微孢子虫(Microspora)是一类古老的细胞内专性寄生微生物,寄主范围涉及从原生动物到哺乳动物(包括人)的广泛宿主,是许多具有经济价值的昆虫、甲壳类、鱼类、啮齿类、灵长类等动物的病原体。自1857年Nageli首次发现家蚕微粒子病病原生物Nosema bombycis后,人们对其进行了大量研究,特别是近年来,免疫缺陷患者体内微孢子虫的发现,更加引起了生物学界和医学界的广泛关注。其主要生物学特征概括如下:营细胞内专性寄生;具单细胞孢子,孢子内含1-2个核,或简或繁的挤出器,不含线粒体,原始的高尔基
体,似原核生物的核糖体。
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鳞翅目昆虫种类繁多,对农业生产和人类生活产生重大影响,宿主昆虫与病毒相互关系的研究对于利用病毒杀虫剂进行害虫治理和益虫病毒性疾病的预防具有重要意义.因此,鳞翅目昆虫与病毒的互作研究显得尤为重要,宿主昆虫的免疫系统在抗病毒感染过程中发挥着关键作用,对病毒产生不同程度的免疫反应.本文综述了昆虫围食膜和中肠对病毒入侵的防御作用,病毒进入体腔后昆虫所产生的细胞免疫和体液免疫反应,以及RNAi、细胞的自噬与凋亡、Toll、Imd、JAK-STAT和STING信号通路等相关的抗病毒免疫途径,并对昆虫抗病毒免疫研究的制约因素和未来鳞翅目昆虫抗病毒免疫的研究重点进行了讨论,以期为害虫的生物防治和益虫疾病的防控提供理论依据. 相似文献
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微孢子虫生物多样性研究的述评 总被引:4,自引:0,他引:4
微孢子虫作为一类专营细胞内寄生的低等的原生动物,有着比较悠久的进化历史。微孢子虫是一种既具有真核生物特征又具有原核生物特征的生物,同样具有生物多样性的本质,文章尝试用生物多样性的概念和原理,阐述原始的真核寄生物微孢子虫的物种多样性、遗传多样性和生态系统多样性的研究概况。 相似文献
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用电镜技术研究蓖麻蚕微孢子虫各发育阶段的超微结构,发现其裂殖体和母孢子具双核,其细胞核由双层单位膜所包裹,核具半圆形的纺锤空斑,细胞质中有内质网和丰富的核糖体,但无线粒体。成熟的孢子壁由外壳、内壳及孢子膜组成,孢子器具有片层结构的极质体和后液泡,极丝为10—11圈,孢质含有核糖体和一对细胞核。 相似文献
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This report provides a detailed ultrastructural study of the life cycle, including proliferative and sporogonic developmental stages, of the first Pleistophora species (microsporidium) obtained from an immune-incompetent patient. In 1985, the organism obtained from a muscle biopsy was initially identified as belonging to the genus Pleistophora, based on spore morphology and its location in a sporophorous vesicle. Since that initial report, at least two new microsporidial genera, Trachipleistophora and Brachiola, have been reported to infect the muscle tissue of immunologically compromised patients. Because Trachipleistophora development is similar to Pleistophora, and as Pleistophora was only known to occur in cold-blooded hosts, the question of the proper classification of this microsporidium arose. The information acquired in this study makes it possible to compare Pleistophora sp. (Ledford et al. 1985) to the known human infections and properly determine its correct taxonomic position. Our ultrastructural data have revealed the formation of multinucleate sporogonial plasmodia, a developmental characteristic of the genus Pleistophora and not Trachipleistophora. A comparison with other species of the genus supports the establishment of a new species. This parasite is given the name Pleistophora ronneafiei n. sp. 相似文献
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Hak Ryul KIM 《Entomological Research》2005,35(1):1-8
Lipophorin (Lp) has an approximate native molecular weight of 730 kDa for Bombyx mori and consists of ApoLp‐I and ApoLp‐II with molecular weights of 250 kDa and 90 kDa for B. mori and 230 kDa and 80 kDa for Hyphantria cunea and 230 kDa and 49 kDa for Lymantria dispar, respectively. Lipid in Lp was mostly composed of neutral lipid. Lp of B. mori maintains constant level during larval and pupal stages but greatly increases during adult stage in both male and female. Lp of H. cunea appeared in great amounts in protein yolk bodies of ovary when vitellogenesis is actively taking place and was present in testicular fluid but not in the peritoneal sheath and cysts of testis. ApoLp‐III of B. mori has a molecular weight of 17 kDa and similar amino acid composition as those of other species Lp. H. cunea apoLp‐III has a molecular weight of 18 kDa and was present in all stages and in the protein body of ovary and in the cyst of testis. ApoLp‐III is synthesized in larval and adult fat body. cDNA sequence of Spodoptera litura apoLp‐III encodes a 188 amino acid polypeptide including a 22 amino acid leader peptide. Galleria mellonella Lp receptor has an approximate molecular weight of 97 kDa and 110 kDa under non‐reducing and reducing conditions, respectively and bound HDLp specifically. Lp receptor cDNA of G. mellonella showed th pattern of the VLDL receptor belonging to the LDL receptor family. The variant Lp receptors were expressed in the fat body of G. mellonella; one is a Lp receptor which lacks 84 bp of O linked sugar domain and the other is a full length form of the Lp receptor. The Lp receptor from the fat body of G. mellonella was differently expressed depending on the tissue and the developmental stages with specific abundance in prepupal stage. 相似文献
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J.S. Dugdale 《New Zealand journal of zoology.》2013,40(4):679-687
Abstract The composition of the New Zealand Lepidoptera fauna is briefly described, and affinities within Tortricidae analysed. Sixty-five genera are used to indicate four possible sets of relationships, but shortcomings of taxonomic interpretations are outlined. Except for species with a wide dispersal range (some 6% of the fauna) most show affinities consonant with terrane biogeography. The panbiogeographic methodology is a potent tool in systematics, giving direction to the research effort. 相似文献
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DAVID C. LEES 《Zoological Journal of the Linnean Society》1992,106(2):163-170
Males of the uraniid moth genus Urania possess a stridulatory organ on the prothoracic leg. This organ represents an autapomorphy for the genus. The sound-producing mechanism consists of a peg formed of specialized scales on the coxa which produces a train of high pitched clicks when scraped against scales on the proximal end of the femur. The proximal end of the femur is enlarged compared with that of the females and would serve to amplify the sound pulse. Stridulation occurs during a series of rapid forward jerks of the forelegs. The sound produced by Urania consists of a low amplitude pulse audible to humans at short range but with a strong ultrasound component. It has not yet been observed in the wild and its function in these moths is unknown, but it may be used during intrasexual or perhaps intersexual communication. This organ is unlikely to have been evolved originally as a defence against nocturnal predators since the genus is a member of an exclusively diurnal clade and females lack the organ. Stridulation occurs in conjunction with fanning-out of the foreleg femoral hair pencil and this invites speculation as to a route for evolution of the organ. 相似文献
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空间转录组技术旨在对细胞的基因表达进行定量测量,同时提供细胞在组织空间的具体位置信息.与传统的转录组技术相比,空间转录组技术能获得细胞在组织生理环境下真实的基因表达特征,以及与微环境的关系,进一步推进对正常和病理状态下细胞特性的理解.近年来,空间转录组技术的发展取得了重要的进展,检测的细胞通量、转录本数量和质量不断提高... 相似文献
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RNA interference in Lepidoptera: an overview of successful and unsuccessful studies and implications for experimental design 总被引:5,自引:0,他引:5
Terenius O Papanicolaou A Garbutt JS Eleftherianos I Huvenne H Kanginakudru S Albrechtsen M An C Aymeric JL Barthel A Bebas P Bitra K Bravo A Chevalier F Collinge DP Crava CM de Maagd RA Duvic B Erlandson M Faye I Felföldi G Fujiwara H Futahashi R Gandhe AS Gatehouse HS Gatehouse LN Giebultowicz JM Gómez I Grimmelikhuijzen CJ Groot AT Hauser F Heckel DG Hegedus DD Hrycaj S Huang L Hull JJ Iatrou K Iga M Kanost MR Kotwica J Li C Li J Liu J Lundmark M Matsumoto S Meyering-Vos M Millichap PJ 《Journal of insect physiology》2011,57(2):231-245
Gene silencing through RNA interference (RNAi) has revolutionized the study of gene function, particularly in non-model insects. However, in Lepidoptera (moths and butterflies) RNAi has many times proven to be difficult to achieve. Most of the negative results have been anecdotal and the positive experiments have not been collected in such a way that they are possible to analyze. In this review, we have collected detailed data from more than 150 experiments including all to date published and many unpublished experiments. Despite a large variation in the data, trends that are found are that RNAi is particularly successful in the family Saturniidae and in genes involved in immunity. On the contrary, gene expression in epidermal tissues seems to be most difficult to silence. In addition, gene silencing by feeding dsRNA requires high concentrations for success. Possible causes for the variability of success in RNAi experiments in Lepidoptera are discussed. The review also points to a need to further investigate the mechanism of RNAi in lepidopteran insects and its possible connection to the innate immune response. Our general understanding of RNAi in Lepidoptera will be further aided in the future as our public database at http://insectacentral.org/RNAi will continue to gather information on RNAi experiments. 相似文献
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Patterns of postzygotic isolation in Lepidoptera 总被引:11,自引:0,他引:11
Presgraves DC 《Evolution; international journal of organic evolution》2002,56(6):1168-1183
I present patterns characterizing the evolution of intrinsic postzygotic isolation in Lepidoptera by analyzing data from the literature on genetic distance, strength of hybrid sterility and inviability, biogeography, and natural hybridization. Using genetic distance as a proxy for time, I investigate the time-course of the evolution of postzygotic isolation and the waiting times to particular hybrid fitness problems. The results show that postzygotic isolation increases gradually as species diverge, but that hybrid sterility evolves faster than hybrid inviability. The overwhelming preponderance of female-specific hybrid problems in Lepidoptera shows that Haldane's rule (the preferential sterility or inviability of the heterogametic sex) is well obeyed. Together the rates and patterns characterizing the accumulation of postzygotic isolation allow several tests of the composite theory of Haldane's rule. Interestingly, comparing these data with those from Drosophila reveals that Haldane's rule for sterility evolves as fast (if not faster) in Lepidoptera. Finally, I show that a substantial fraction of sympatric species hybridizes in nature and that the majority of these suffer some level of hybrid sterility or inviability. 相似文献
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Bong‐Kyu Byun Young Mi Park Sora Kim Bong‐Woo Lee Namsik Bang 《Entomological Research》2012,42(5):281-283
In this paper, we report C. agronoma Meyrick for the first time from South Korea. Photographs of adults and genitalia are provided, with brief comments on distribution and biology. 相似文献
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ABSTRACT This study was conducted to determine the effects of diflubenzuron (DFB) on the growth and development of the silkworm, Bombyx mori (L.). The DFB treatment extended abnormally the larval duration and affected negatively on larval spinning of the 5th instar. All the larvae treated with high DFB concentration (2.5 × 10-1 and 2.5x 10-1 μg/μl) lost their spinning capability and finally died, whereas 62% of larvae treated with low DFB concentration (2.5 × 10-1 μg/μl)) spinned cocoon. The larval weights depended sensitively on the DFB treatment period rather than on the DFB concentration. The DFB treatment decreased the larval maturity less than 6% without regard to the concentration and treatment period. All the larva, when treated with DFB before the 5th days of the 5th instar, were not matured. 相似文献