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Venom from the endoparasitic wasp Pimpla turionellae L. (Hymenoptera: Ichneumonidae) was found to contain a complex mixture of biogenic amines, noradrenalin, phospholipase B, and several proteins and peptides. The amount of noradrenalin and serotonin was found to be highest in venom from newly emerged wasps and decreased with age. Histamine was detected in minute amounts in comparison to the other venom components, and declined with increasing age of the parasitoids. Total peptides and proteins detected by reversed-phase HPLC increased with host age. Old-aged (30-33 days after emergence) wasps contained 2-fold more phospholipase B than young (<10 days [d] old) or medium-aged (10-22-d-old) females. Increases in phospholipase B alone, however, did not account for all changes in total venom protein because by 40 days after emergence, the levels of this enzyme began to decline while the amount of total protein was higher than in younger wasps. For all venom components detected, the amount present in the venom sharply decreased following host exposure. This was presumed to be the result of venom depletion associated with envenomation. Consistent with this view were the modest increases in venom components in wasps displaying a decreased rate of parasitization. When adult females were offered honey alone or in combination with feeding on hosts, no significant changes in venom composition were observed, with the exception of noradrenalin, which was found to be 5 times higher in concentration in wasps fed honey only. These results suggest that wasp age and incidence of parasitism are more important features influencing the composition of venom than the diet of adult females.  相似文献   

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The ants use their venom for predation, defense, and communication. The venom of these insects is rich in peptides and proteins, and compared with other animal venoms, ant venoms remain poorly explored. The objective of this study was to evaluate the protein content of the venom in the Ponerinae ant Pachycondyla striata. Venom samples were collected by manual gland reservoir dissection, and samples were submitted to two‐dimensional gel electrophoresis and separation by ion‐exchange and reverse‐phase high‐performance liquid chromatography followed by mass spectrometry using tanden matrix‐assisted laser desorption/ionization with time‐of‐flight (MALDI‐TOF/TOF) mass spectrometry and electrospray ionization‐quadrupole with time‐of‐flight (ESI‐Q/TOF) mass spectrometry for obtaining amino acid sequence. Spectra obtained were searched against the NCBInr and SwissProt database. Additional analysis was performed using PEAKS Studio 7.0 (Sequencing de novo). The venom of P. striata has a complex mixture of proteins from which 43 were identified. Within the identified proteins are classical venom proteins (phospholipase A, hyaluronidase, and aminopeptidase N), allergenic proteins (different venom allergens), and bioactive peptides (U10‐ctenitoxin Pn1a). Venom allergens are among the most expressed proteins, suggesting that P. striata venom has high allergenic potential. This study discusses the possible functions of the proteins identified in the venom of P. striata.  相似文献   

4.
The wingless mutant flügellos ( fl ) of the silkworm lacks all four wings. Although wing discs of the fl seem to develop normally until the fourth larval instar, wing morphogenesis stops after the fourth larval ecdysis, probably caused by aberrant expression of an unidentified factor, referred to as fl . To characterize factor fl , the wing discs dissected from the wild-type (WT) and fl larvae were transplanted into other larvae and developmental changes of the discs were examined. When the wing disc from a WT larva was transplanted into another WT larva and allowed to grow until emergence, a small wing appeared that was covered with scales. Thus, the transplanted wing discs can develop autonomously, form scales and evert from adult skin. The WT wing discs transplanted into the fl larvae also developed at a high rate. However, the fl wing discs transplanted into the WT larvae did not develop during the larval to pupal developmental stages. These data suggest that the fl gene product (factor fl) works in the wing disc cells during wing morphogenesis. Its function cannot be complemented by hemolymph in the WT larva. It is also implied that the level of humoral factors and hormones required for wing morphogenesis are normally maintained in the fl larva.  相似文献   

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Ciliates (Protista) have a complex species structure, which means that in several genera the morphological species are differentiated into cryptic species with isolated gene pools (called syngens). Problems of speciation are well known in the genus Paramecium, and especially in the P. aurelia sibling (cryptic) species complex within it. However, the problem of the existence of such species within P. jenningsi was, until recently, still unsolved. Here we present the results of studies based on an analysis of 16 loci (both nuclear and mitochondrial), strain crosses and cytological preparations. The obtained data allowed us not only to study relationships of the P. jenningsi complex and other morphospecies within the Paramecium subgenus, but also to confirm the existence of three isolated reproductive groups within the former P. jenningsi and to propose binominal names for each of them: P. primjenningsi, P. bijenningsi, and P. trijenningsi. In our view, the studied species meet the criteria of a species complex because they can be differentiated based on strain crosses and molecular characteristics, but they cannot be differentiated based on morphological features alone.

http://zoobank.org/urn:lsid:zoobank.org:pub:9209CD4C-A255-4A33-BFC1-CE336244C200  相似文献   

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黄芳  时敏  陈学新  章金明 《昆虫学报》2011,54(9):989-996
半闭弯尾姬蜂Diadegma semiclausum是小菜蛾Plutella xylostella的优势内寄生蜂, 拥有毒液、多分DNA病毒(PDV)等寄生因子,能有效调控寄主幼虫的营养生理和免疫系统, 但其毒液在这过程中的功能不明。本文利用SDS-PAGE方法分析了半闭弯尾姬蜂毒液的蛋白组分,利用寄主幼虫血细胞体外原代培养的方法,研究了小菜蛾幼虫血细胞噬菌能力在半闭弯尾姬蜂寄生后的变化情况。结果表明:半闭弯尾姬蜂毒液蛋白分子量主要集中在35~220 kDa之间,少数小于15 kDa,但分子量处于35~70 kDa之间的蛋白含量较高,与其他寄生蜂毒液蛋白相似。半闭弯尾姬蜂毒液单独对寄主小菜蛾幼虫功能血细胞(浆血细胞和颗粒血细胞)的延展能力和吞噬功能不产生破坏作用。但半闭弯尾姬蜂寄生后短时间内,寄主功能血细胞的延展受到抑制,然而功能血细胞仍然能识别外源异物, 却无法进一步吞噬外源物; 寄生后24 h,功能血细胞的延展力恢复,颗粒血细胞的吞噬作用可顺利完成。本研究证明了半闭弯尾姬蜂寄生能暂时性地抑制颗粒血细胞的延展性从而影响其噬菌过程。  相似文献   

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Renal impairment is associated with CNS dysfunctions and the accumulation of uremic toxins, such as indoxyl sulfate, in blood. To evaluate the relevance of indoxyl sulfate to CNS dysfunctions, we investigated the brain-to-blood transport of indoxyl sulfate at the blood-brain barrier (BBB) using the Brain Efflux Index method. [(3)H]Indoxyl sulfate undergoes efflux transport with an efflux transport rate of 1.08 x 10(-2)/min, and the process is saturable with a Km of 298 microm. This process is inhibited by para-aminohippuric acid, probenecid, benzylpenicillin, cimetidine and uremic toxinins, such as hippuric acid and 3-carboxy-4-methyl-5-propyl-2-furanpropanoic acid. RT-PCR revealed that an OAT3 mRNA is expressed in conditionally immortalized rat brain capillary endothelial cell lines and rat brain capillary fraction. Xenopus oocytes expressing OAT3 were found to exhibit [(3)H]indoxyl sulfate uptake, which was significantly inhibited by neurotransmitter metabolites, such as homovanillic acid and 3-methoxy-4-hydroxymandelic acid, and by acyclovir, cefazolin, baclofen, 6-mercaptopurine, benzoic acid, and ketoprofen. These results suggest that OAT3 mediates the brain-to-blood transport of indoxyl sulfate, and is also involved in the efflux transport of neurotransmitter metabolites and drugs. Therefore, inhibition of the brain-to-blood transport involving OAT3 would occur in uremia and lead to the accumulation of neurotransmitter metabolites and drugs in the brain.  相似文献   

8.
Leptomonas wallacei is a monoxenic trypanosomatid that colonizes the digestive tract of the phytophagous hemipteran Oncopeltus fasciatus. This infection was specific and took place exclusively in midgut intestinal ventricles V3 and V4, and in the hindgut. Abundances of parasites in the hindgut were 54% less than those in the hindgut. Parasites in the hindgut were more slender and had a longer flagellum than those from the hindgut, which were rounded, with a shorter flagellum. Moreover, hindgut forms expressed sugar residues on the cell surface, recognized by the lectins from Griffonia simplicifolia-I (alpha-galactose, alpha-N-acetyl-galactosamine) and Helix pomatia (N-acetyl-galactosamine); those sugar residues were not present in protozoa from the midgut. In culture, parasites were morphologically similar to midgut forms, but differed from them because they did not express sugar residues that bind to lectin (beta-galactose(1-3) N-acetyl-galactosamine) from Arachis hypogaea.  相似文献   

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