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Simchuk AP 《Genetika》2008,44(4):488-495
The effect of genetic variation of oak (Quercus pubescens L. and Q. petraea L.) on the genotype fitness components in green oak leafroller moth larvae (Tortrix viridana L.) at esterase (Est-4) and protease (Pts-4) loci was studied. The samples of larvae were collected from nine oak trees, whose genetic variation was assayed by RAPD-PCR using primer OPA14. The contributions of the factors of Yoak species/genotype and green oak leafroller moth genotype and their interaction to the variation of important size-related traits of the larvae were evaluated by two-way ANOVA. It was shown that the same larval genotype can display maximum fitness on the trees of one species or genotype and minimal, on the trees of other species or genotype. The interactions between the oak genotype and green oak leafroller moth genotype factors lead to the relationships that appear in statistically significant associations between genotype classes of green oak leafroller moth and oak. These results are discussed from the standpoint of a recently developed new field, community or ecosystem genetics.  相似文献   
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Bryce, J. H. and ap Rees, T. 1985. Comparison of the respiratorymetabolism of Plantago lanceolata L. and Plantago major L.—J.exp. Bot. 36 1559–1565. The aim of this work was to discover if the respiratory metabolismof the roots of Plantago lanceolata L. differed from that ofthe roots of Plantago major L. Measurements of oxygen uptakeand dry weight of excised root systems during growth of seedlingsprovided evidence that the two species differed in the amountof respiration needed to support a given increase in dry weight.Excised root systems were given a 6-h pulse in [U-14C]sucrosefollowed by a 16.5-h chase in sucrose. The detailed distributionof 14C amongst the major components of the roots at the endof the pulse and the chase revealed no significant differencebetween the two species. Patterns of 14CO2 production from [1-14C],[2-14C], [3,4-14C], and [6-14C]glucose of excised root systemsfrom plants of three ages were similar for the two species.It is suggested that there is no conclusive evidence for anysignificant inherent difference in the respiratory metabolismof the roots of the two species. Key words: 14C sugar metabolism, respiration, roots, Plantago  相似文献   
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Rapid recycling of triose phosphates in oak stem tissue   总被引:10,自引:3,他引:7  
We report the carbon-13 and oxygen-18 isotope ratios in cellulose from the early and late wood of pedunculate oak (Quercus robur L.). The δ13 C value of the early wood correlates best with that of the late wood of the previous year. The δ18O value of the early wood correlates best with that of the late wood of the same year. We suggest that a biochemical explanation of these data is that there is a rapid cycle between hexose monophosphates and triose phosphates in oak stem tissue during cellulose synthesis. Evidence in support of this explanation is provided by the intramolecular distribution of 14C in labelled fructose extracted from cores of wood that had been supplied with [1?14C]- and [6-14C]glucose.  相似文献   
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From a single aflatoxin B1 oxime — bovine serum albumin conjugate, polyclonal and monoclonal antibody preparations were produced. The four rabbit polyclonal antisera were specific for aflatoxin Bi in a microtitration plate enzyme — linked immunosorbent assay. The monoclonal antibodies showed a wide range of differing specificities, recognizing, for example, aflatoxins B1, B2, G1 and G2; B1 and B2; B1 and G1; and G1 alone. No antibody preparations reacted with aflatoxin M1. The significance of these results to the strategy of anti-aflatoxin antibody production for use in quantitative enzyme immunoassays is discussed.  相似文献   
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Fucose is a major constituent of the protein- and lipid-linked glycans of the various life-cycle stages of schistosomes. These fucosylated glycans are highly antigenic and seem to play a role in the pathology of schistosomiasis. In this article we describe the identification and characterization of two fucosyltransferases (FucTs) in cercariae of the avian schistosome Trichobilharzia ocellata, a GDP-Fuc:[Galbeta1-- >4]GlcNAcbeta-R alpha1-->3-FucT and a novel GDP-Fuc:Fucalpha-R alpha1-- >2-FucT. Triton X-100 extracts of cercariae were assayed for FucT activity using a variety of acceptor substrates. Type 1 chain (Galbeta1- ->3GlcNAc) based compounds were poor acceptors, whereas those based on a type 2 chain (Galbeta1-->4GlcNAc), whether alpha2'-fucosylated, alpha3'-sialylated, or unsubstituted, and whether present as oligosaccharide or contained in a glycopeptide or glycoprotein, all served as acceptor substrates. In this respect the schistosomal alpha3- FucT resembles human FucT V and VI rather than other known FucTs. N- ethylmaleimide, an inhibitor of several human FucTs, had no effect on the activity of the schistosomal alpha3-FucT, whereas GDP-beta-S was strongly inhibitory. Large scale incubations were carried out with Galbeta1-->4GlcNAc, GalNAcbeta1-->4GlcNAcbeta-O -(CH2)8COOCH3 and Fucalpha1-->3GlcNAcbeta1-->2Man as acceptor substrates and the products of the incubations were isolated using a sequence of chromatographic techniques. By methylation analysis and 2D-TOCSY and ROESY1H-NMR spectroscopy the products formed were shown to be Galbeta1-- >4[Fucalpha1-->2Fucalpha1-->3]GlcNAc, GalNAcbeta1-->4[Fucalpha1-- >2Fucalpha1-->3]GlcNAcbe ta-O-(CH2)8COOCH3, and Fucalpha1-->2Fucalpha1-- >3GlcNAcbeta1-->2Man, respectively. It is concluded that the alpha2- FucT and alpha3-FucT are involved in the biosynthesis of the (oligomeric) Lewisx sequences and the Fucalpha1-->2Fucalpha1-->3GlcNAc structural element that have been described on schistosomal glycoconjugates.   相似文献   
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Genetic polymorphism of the two Palaearctic sulphur butterflies Colias crocea Fourc. and Colias erate Esp. was examined in serial samples using RAPD-PCR analysis of total cellular DNA. The primers OPA-01, OPA-03, OPA-04, OPA-08 were used. Taxon-specific molecular markers have been found for each species (markers OPA-08(250), OPA-08(380) were associated with rounded valve margin; marker OPA-04(400) was associated with angled valve margin). The genetic diversity of C. erate is considerably less than that of C. crocea. Genetic evidence for interspecific hybridization between C. crocea and C. erate is presented. Interspecific hybrids in question (paratypical forms such as f. chlorodona and f. pseudochrysodona) are situated at intermediate position with regard to the parental species on dendrograms (UPGMA) and maximal spanning trees (MST). Completely additional RAPD-spectra were not obtained though taxonomic status of these paratypical forms stay still vague. Only f. eratoides has DNA markers that are absent in spectra of other specimens tested. Probably it is a cryptic species unrevealed by common morphological and biochemical methods and its investigation by the methods of molecular genetics (sequence of cloned DNA) is very desirable.  相似文献   
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Background  

Bothrops atrox is responsible for the majority of snakebite accidents in the Brazilian Amazon region. Previous studies have demonstrated that the biological and pharmacological activities of B. atrox venom alter with the age of the animal. Here, we present a comparative proteome analysis of B. atrox venom collected from specimens of three different stages of maturation: juveniles, sub-adults and adults.  相似文献   
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