摘要：
Shikonin and its derivatives are formed in large amounts in dark-cultured Onosma paniculatum cells. In order to isolate and identify the genes regulating shikonin biosynthesis, we constructed and characterized a full-length-enriched cDNA Library of dark-cultured cells by using the SMART (Switching Mechanism At 5'-end of RNA Transcript) cDNA synthesis and LD-PCR (tong-distance PCR) strategies. The titer of the primary cDNA library was 1.04 x 10(6) pfu/mL with a recombination rate of 99.60%. Most of the cDNA inserts ranged from 1.0 to 2.5 kb, and 78.33% of the 76 randomly selected clones contained full-length coding regions. Expression analysis of randomly selected genes by small scale microarray revealed that 23 genes were down-regulated, including 17 genes with known functions, 2 genes with putative functions, and 4 novel genes, and that 3 genes were up-regulated (two-fold) in cells cultured under white tight as compared with those cultured in the dark. Interestingly, two of the down-regulated genes, encoding aci-reductone dioxygenase (ARD)-like protein and ethylene responsive factor (ERF), are involved in ethylene biosynthesis and signal transduction, implying that ethylene might play an important role as a signal molecule in tight-regulated shikonin formation. These data contribute to a better understanding of light-involvement in regulating the formation of plant secondary metabolites. (C) 2007 Elsevier GmbH. All rights reserved.
关键词：
Braconidae;China;Microgastrinae;Microplitis;New species
摘要：
Five new species of the genus Microplitis Foerster (Hymenoptera: Braconidae: Microgastrinae) are described and illustrated: Microplitis basipallescentis, sp. nov., M. brevispina, sp. nov., M. carinata, sp. nov., M. changbaishana, sp. nov. and M. crassiantenna, sp. nov. All specimens are deposited in the College of Biosafety Science and Technology, Hunan Agricultural University, Changsha, China.
摘要：
A novel alkaloid, hupcrispatine (1), has been isolated from the unique Chinese species Huperzia crispate Ching. The structure of hupcrispatine has been elucidated as 9-amino-6-methyl-3-quinolone on the basis of spectral evidence.
摘要：
The family Roeslerstammiidae is recorded from Mailand China for the first time, including one new record genus, Agriothera Meyrick, 1907, and two new record species, Agriothera doipakiae Moriuti, 1987 and Agriothera issikii Moriuti, 1978. The wing venations of these species are illustrated for the first time. A key to the species of this family from Mailand China is also presented.
关键词：
strain localization;locally-deformed bands;shear bands;two-phase equilibrium;granular model of sand
摘要：
In contrast to the traditional interpretation of shear bands in sand as a bifurcation problem in continuum mechanics, shear bands in sand are considered as high-strain phase (plastic phase) of sand and the materials outside the bands are still in low-strain phase (elastic phase), namely, the two phases of sand can coexist under certain condition. As a one-dimensional example, the results show that, for materials with strain-softening behavior, the two-phase solution is a stable branch of solutions, but the method to find two-phase solutions is very different from the one for bifurcation analysis. The theory of multi-phase equilibrium and the slow plastic flow model are applied to predict the formation and patterns of shear bands in sand specimens, discontinuity of deformation gradient and stress across interfaces between shear bands and other regions is considered, the continuity of displacements and traction across interfaces is imposed, and the Maxwell relation is satisfied. The governing equations are deduced. The critical stress for the formation of a shear band, both the stresses and strains inside the band and outside the band, and the inclination angle of the band can all be predicted. The predicted results are consistent with experimental measurements.
摘要：
In cucumber, we show salicylic acid only induce local acquired resistance (LAR), whereas acibenzolar-S-methyl (ASM) can induce LAR and systemic acquired resistance (SAR) to plant diseases. Jasmonic acid (JA) can induce local acquired susceptibility (LAS) and systemic acquired susceptibility (SAS). ASM treatment of lower first leaves leads to the accumulation of cucumber acidic class III chitinase (CHI2) in untreated upper leaves and effectively suppresses lesion formation on those leaves. In contrast, JA treatment completely suppresses CHI2 gene expression and causes plants to be more susceptible to Colletotrichum orbiculare. ASM-induced SAR can effectively antagonize the JA-induced SAS, providing a response that is midway between what would be expected with either JA or ASM by themselves. (C) 2008 Elsevier Ltd. All rights reserved.
摘要：
Improvement of animal embryo sexing depends upon high-titer serologically detected male (SDM) antibody fragments. SDM sera collected from isogenic C57BL/7 female mice after inoculation with male spleen cells were characterized and used for construction of a recombinant Fab antibody library against SDM antigen, and used for analysis of the binding capacity and specificity to SDM antigen. The heavy-chain Fd and full-length light-chain K were amplified by RT-PCR from a mouse (#6) that'ed high-titer antiserum. The amplified product was inserted into the pComb3 vector followed by co-infections with the help phage VCSM 13 for construction of the phage library, which gave 1.5 x 10(7) colonies with the titer of 3.2 x 10(11) pfu/ml by a recombination rate of 80%. Sequence analysis of the PCR products of plasmid DNA of E5 clones showed that V-H and V-k had common characteristics shared by other known variable region of antibodies. The Fab antibody libraries against SDM antigen were enriched by three cycles of affinity enrichment with male spleen cells, and two cycles of non-specific absorption with female spleen cells. The ELISA results showed that 9 of 15 clones had binding capacity to the SDM antigen. This is the first report on a phage display library of SDM antigen. The mouse Fab antibody library could be used for identifying SDM antigen, and for the development of sex determination of early embryos in mammals. (C) 2007 Elsevier B.V. All rights reserved.
摘要：
The photosensitive resveratrol was successfully encapsulated in yeast cells for the first time, as characterized by FT-IR spectra, fluorescence and confocal micrographs of the yeast cells, resveratrol and microcapsules. The release characteristic of the obtained yeast-encapsulated resveratrol in simulated gastric fluid was evaluated, and its storage stability as a powder was investigated at 25 degrees C/75% relative humidity (RH), 25 degrees C/90% RH and 60 degrees C under the laboratory fluorescent lighting conditions (ca. 300 lx) or in the dark. Also, the scavenging capacity of yeast-encapsulated resveratrol on DPPH radical was compared with that of non-encapsulated resveratrol. It could be demonstrated clearly that no chemical changes occurred during the encapsulation. Besides, the DPPH radical-scavenging activity increased after the encapsulation. In addition, the yeast-encapsulated resveratrol exhibited good stability, and its bioavailability was enhanced as a result of increased solubility of resveratrol and sustained releasing. (c) 2007 Elsevier B.V. All rights reserved.
摘要：
SummaryImprovement of drought tolerance in plants depends upon understanding their molecular responses to dehydration stress. The drought resistance of 14 varieties of tall fescue (Festuca arundinacea Schreb.) was analysed by measuring various physiological traits under high temperature and drought conditions. A dehydration-responsive element-binding-2 (DREB2) homologue cDNA from the cultivar ‘Plantation’, with high drought tolerance, designated FapDREB2, was isolated and sequenced. The FapDREB2 cDNA was predicted to encode a protein of 262 amino acid residues, with a molecular mass of 41.3 kDa and a pI of 5.28. Its deduced protein sequence, with a conserved AP2 DNA-binding domain, shared characteristics with the DREB2 gene family based on sequence homology, structure and phylogenetic analysis. Expression of the FapDREB2 gene in different plant organs indicated that its transcripts were abundant in leaves and leaf sheaths, and scarce in roots. In addition, FapDREB2 gene expression under drought and high temperature conditions was stronger than without such treatments in the laboratory. FapDREB2 mRNA accumulated in response to various abiotic stresses, confirming that its expression was induced more prominently by drought or salt treatment than by cold stress, and did not respond to abscisic acid (ABA) treatment. FapDREB2 gene expression in seedlings grown in a study plot varied irregularly under drought and high temperature conditions, in contrast to seedlings grown with drought treatment in the laboratory. This suggests that expression of the DREB2 transcription factor would be complex during plant responses to different stresses. We concluded that the FapDREB2 gene is involved in plant responses to drought or salt stress through an ABA-independent pathway, which may lead to a better understanding of the regulatory mechanism of the DREB2 transcription factor in tall fescue.
期刊：
EUROPEAN JOURNAL OF ENTOMOLOGY,2008年105(4):599-606 ISSN：1210-5759
通讯作者：
Ge, Feng
作者机构：
[Zeng, Ju-Ping; Ge, Feng; Su, Jian-Wei] Chinese Acad Sci, Inst Zool, State Key Lab Integrated Management Pest Insects, Beijing 100101, Peoples R China.;[Zeng, Ju-Ping] Chinese Acad Sci, Grad Univ, Beijing 100049, Peoples R China.;[Wang, Yong] Hunan Agr Univ, Changsha 410128, Hunan, Peoples R China.
通讯机构：
[Ge, Feng] C;Chinese Acad Sci, Inst Zool, State Key Lab Integrated Management Pest Insects, Beijing 100101, Peoples R China.
关键词：
Acclimation;Cold hardiness;De-acclimation;Dendrolimus tabulaeformis;Low molecular weight sugars;Supercooling point
摘要：
Pine caterpillar, Dendrolimus tabulaeformis Tsai et Liu, is a major pine pest in North China. The larvae enter diapause in the third or fourth instar before winter. Supercooling points (SCP) and cold hardiness of the diapausing larvae were investigated and compared in non-acclimated, acclimated and de-acclimated larvae. A bimodal frequency distribution was observed with a break point of -14°C in the SCP. Larvae in the low group (LG, SCP ≤ -14°C) were more cold tolerant with lower lethal temperatures than those in the high group (HG, SCP > -14°C). This bimodality occurred in three patterns, LG (> 60% of individuals in LG), LG-HG (< 60% of individuals in LG and HG) and HG (> 60% of individuals in HG), in response to cold acclimation and de-acclimation. The cold hardiness was ranked as: LG > LG-HG > HG pattern. Cold hardiness was enhanced by an increase in concentrations of trehalose, galactose, glucose and mannose in the haemolymph as well as by decrease in metabolism after cold acclimation, but was lost after de-acclimation. Loss of cold hardiness was correlated with decrease in sugars and increase in metabolic rate. In conclusion, the species is a chill tolerant insect, adopting the strategy of depressing SCP through accumulation of low molecular weight sugars in the haemolymph, concomitant with metabolic depression.
摘要：
Drought and high-salinity are the important constraints that severely affect plant development and crop yield worldwide. It has been established that ethylene response factor (ERF) proteins play important regulatory roles in plant response to abiotic and biotic stresses. Our previous researches have revealed that transgenic tobacco over-expressing TERF1 (encoding a tomato ERF protein) showed enhanced tolerance to abiotic stress. Here, we further investigate the function of TERF1 in transgenic rice. Compared with the wild-type plants, overexpression of TERF1 resulted in an increased tolerance to drought and high-salt in transgenic rice. And the enhanced tolerance may be associated with the accumulation of proline and the decrease of water loss. Furthermore, TERF1 can effectively regulate the expression of stress-related functional genes Lip5, Wcor413-l, OsPrx and OsABA2, as well as regulatory genes OsCDPK7, OsCDPK13 and OsCDPK19 under normal growth conditions. Our analyses of cis-acting elements show that there exist DRE/CRT and/or GCC-box existing in TERF1 targeted gene promoters. Our results revealed that ectopic expression of TERF1 in rice caused a series of molecular and physiological alterations and resulted in the transgenic rice with enhanced tolerance to abiotic stress, indicating that TERF1 might have similar regulatory roles in response to abiotic stress in tobacco and rice.
