Sep 2007, Volume 2 Issue 3
    

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  • LU Yiqin, LIU Junfan
    Considerable advances in the research field of erythrocyte membrane were achieved in the recent two decades. New findings in the structure-function correlation and interactions of erythrocyte membrane proteins have attracted extensive attention. Interesting progress was also made in the molecular pathogenesis of erythrocyte membrane disorders. Advances in the composition, function and interaction of erythrocyte membrane proteins, erythrocyte membrane skeleton, and relevant diseases are briefly described and summarized here on the basis of domestic and world literatures.
  • ZHANG Yufen, ZHANG Dayong
    Most plants can reproduce both sexually and asexually (or vegetatively), and the balance between the two reproductive modes may vary widely between and within species. Extensive clonal growth may affect the evolution of life history traits in many ways. First, in some clonal species, sexual reproduction and sex ratio vary largely among populations. Variation in sexual reproduction may strongly affect plant’s adaptation to local environments and the evolution of the geographic range. Second, clonal growth can increase floral display, and thus pollinator attraction, while it may impose serious constraints and evolutionary challenges on plants through geitonogamy that may strongly influence pollen dispersal. Geitonogamous pollination can bring a cost to plant fitness through both female and male functions. Some co-evolutionary interactions, therefore, may exist between the spatial structure and the mating behavior of clonal plants. Finally, a trade-off may exist between sexual reproduction and clonal growth. Resource allocation to the two reproductive modes may depend on environmental conditions, competitive dominance, life span, and genetic factors. If different reproductive modes represent adaptive strategies for plants in different environments, we expect that most of the resources should be allocated to sexual reproduction in habitats with fluctuating environmental conditions and strong competition, while clonal growth should be dominant in stable habitats. Yet we know little about the consequence of natural selection on the two reproductive modes and factors which control the balance of the two reproductive modes. Future studies should investigate the reproductive strategies of clonal plants simultaneously from both sexual and asexual perspectives.
  • QIN Yingxue, WANG Jun, WANG Shifeng, YAN Qingpi
    Vibrio harveyi, the major causative agent of vibriosis, affects a diverse range of marine cultured organisms over a wide geographical area. However, reports about screening the effective antigen and research on vaccines of V. harveyi are scarce. Flagellin, lipopolysaccharide (LPS) and outer membrane proteins (OMP) are major immunogenic antigens in many Gram-negative bacteria. In this study, the flagellin, OMP and LPS of the V. harveyi TS-628 strain isolated from infected groupers were extracted and Western blot analysis was used to detect the antigenicity of these extractions. Results of the Western blot assay reveal that there are four positive flagellin bands: 35 kDa, 38 kDa, 43 kDa, and 52 kDa, of which the 43 kDa and 52 kDa bands displayed the strongest positive reaction. There are five positive OMP bands about 35 kDa, 38 kDa, 43 kDa, 47 kDa, and 52 kDa, of which the 43 kDa appeared to have the strongest positive reaction although the other four proteins also displayed strong reactions. However, LPS is Western blot-negative. These results indicate that the 43 kDa and 52 kDa flagellin and OMP of size 43 kDa, 52 kDa can be candidates for developing vaccines against V. harveyi.
  • LIU Xiang, WANG Yifei
    Proteins are fundamental components of all living cells and the protein-protein interaction plays an important role in vital movement. This paper briefly introduced the original Resonant Recognition Model (RRM), and then modified it by using the wavelet transform to acquire the Modified Resonant Recognition Model (MRRM). The key characteristic of the new model is that it can predict directly the protein-protein interaction from the primary sequence, and the MRRM is more suitable than the RRM for this prediction. The results of numerical experiments show that the MRRM is effective for predicting the protein-protein interaction.
  • WANG Juan, NI Hong, CHEN Li, CHEN Chengbin, SONG Wenqin
    Cancer-related genes harbored in the loss regions containing a high frequency of hepatocellular carcinoma (HCC) were selected. Related information was gathered and the coding single nucleotide polymorphism (cSNP) sequences were obtained from the single nucleotide polymorphism (SNP) database. The appropriate primers and oligonucleotide probes were then designed in accordance with the SNP sites, and subsequently, the gene chips for detecting SNPs were constructed. Genomic DNA was extracted from blood samples of healthy controls and from patients with HBV infection. The sequences, including the SNPs, were amplified via polymerase chain reaction (PCR) and labeled using digoxigenin deoxyuridine tri-phosphate (Dig-dUTP). The labeled products were then hybridized with the SNP chips. Results confirmed that the differences in allele frequencies of three SNPs EGFL3 (rs947345), Caspase9 (rs2308950), and E2F2 (rs3218171) were distinct between HBV-infected patients and controls, suggesting that these SNPs ocuring in high frequency in HBV-infected individuals may be associated with susceptibility to HCC.
  • WANG Shujing, LIU Yan, LIN Xuesong, FU Xue, XU Jianyong, LIU Xinghan
    To obtain an anti-tumor peptide of Tumstatin and detect its biological activity, the nucleotide sequence encoding 185 203 amino acids (19peptide) of Tumstatin was synthesized and inserted into the fusion protein vector pTYB2. After identification by sequencing and restriction endonucleases, the recombined vector was transformed into BL-21 (DE3) E. coli competent cells. Transformed E. coli BL-21 (DE3) were induced by isopropyl-β-thiogalactopyranoside (IPTG), and then expressed. By 1‚4-dithiothreitol (DTT) reduction, the soluble 19peptide was obtained from a chitin affinity chromatograph. The biological activity of 19peptide was determined by 3-[4‚5-dimethylthiazol-2-y1]-2‚5-dipheny-tetrazolium bromide (MTT) assay, cell growth curve, the effect of the ascitic fluid transfevent H22 hepatoma on mice and via histopathological slices. The purified 19peptide directly inhibited proliferation and migration of murine B16 melanoma cells, SMMC-7721hepatoma carcinoma cells and human umbilical vein endothelial cells (HUVEC). The tumor inhibition rate of mice ascitic fluid transfevent H22 hepatoma was 48.46%. Histopathological slices showed that it could promote tumor tissue necrosis and decrease the density of blood vessels. With higher anti-tumor activity, 19peptide has the potential to become a novel, potent anti-tumor agent.
  • WEI Xiangdong, LAN Congyu, LU Zhijing, YE Changming
    Molecular biological characterization, fruit characters, and nutrients were analyzed for T4 generation of transgenic papaya. All transgenic papaya plants with the mutated replicase (RP) gene from papaya ringspot virus (PRSV) showed high resistance or immunity against PRSV in the field. The RP transgene can be steadily inherited to, and expressed at RNA level, the progenies. The growth characteristics of transgenic papaya were much better than non-transgenic papaya in the field. The non-transgenic papaya seedlings began to show typical symptoms caused by PRSV after being inoculated with PRSV. They died quickly and never grew to produce fruit. The adult trees developed yellow leaves and produced smaller fruits and were doomed to a slow death after some time, while most of transgenic papaya plants (about 91.8%) did not show any symptoms caused by PRSV, and produced more, bigger, and high quality fruits. Compared with non-transgenic plants, the fresh fruit length of T4 generation of transgenic papaya increased 2.6%–5%, and the diameter decreased 0.6%–1.5%. The flesh thickness of fresh fruit increased 12%–15%, which made it fitter for eating. Although the fresh fruit quality changed, there was no significant difference between transgenic and non-transgenic papaya. The quality characteristics of dry fruit including the contents of water, lipid, N, protein, reduced sugar, vitamin A, vitamin C, and carotene in the T4 generation of transgenic papaya were all the same as their non-transgenic parents. This means that transgenic plants and non-transgenic plants are substantially equivalent, and the transgene has no effect on dry fruit quality. In this study, we found that vitamin A and vitamin C in red-fleshed papaya were 1.4–1.8 and 1.78–2.07 times more than the yellow-fleshed ones, respectively, while N and protein were only 84.2%–92.1% and 82.1%–98.9% of the yellow-fleshed ones.
  • CAI Xingxing, LIU Jing, QIU Yinqiu, ZHAO Wei, SONG Zhiping, LU Baorong
    DNA polymorphisms from nucleotide insertion/deletions (InDels) in genomic sequences are the basis for developing InDel molecular markers. To validate the InDel primer pairs on the basis of the comparative genomic study on DNA sequences between an Indica rice 93-11 and a Japonica rice Nipponbare for identifying Indica and Japonica rice varieties and studying wild Oryza. species, we studied 49 Indica, 43 Japonica, and 24 wild rice accessions collected from ten Asian countries using 45 InDel primer pairs. Results indicated that of the 45 InDel primer pairs, 41 can accurately identify Indica and Japonica rice varieties with a reliability of over 80%. The scatter plotting data of the principal component analysis (PCA) indicated that: (i) the InDel primer pairs can easily distinguish Indica from Japonica rice varieties, in addition to revealing their genetic differentiation; (ii) the AA-genome wild rice species showed a relatively close genetic relationship with the Indica rice varieties; and (iii) the non-AA genome wild rice species did not show evident differentiation into the Indica and Japonica types. It is concluded from the study that most of the InDel primer pairs obtained from DNA sequences of 93-11 and Nipponbare can be used for identifying Indica and Japonica rice varieties, and for studying genetic relationships of wild rice species, particularly in terms of the Indica-Japonica differentiation.
  • LUO Yi, WANG Xujie, MEI Mantong, ZHUANG Chuxiong, ZHOU Feng, YAO Juan, ZHAO Junliang, WEI Zengquan, XIE Hongmei
    Dry rice seeds (Oryza sativa, subspecies indica) were sandwiched between nuclear track detectors, aboard the Chinese spaceship Shenzhou-3 for seven days. The seeds were recovered and the genomic polymorphism in 201 plants developed from these seeds was studied using random amplified polymorphism DNA analysis. When compared with plants from ground-based control seeds, the genomic polymorphic bands were amplified in 30.2% of the plants from the seeds exposed in space. The results for sequencing and SNP analyses of the polymorphic bands verified the single nucleotide variations in these plants. Genomic polymorphisms in the consecutive generations of individual plants of the seeds from space were also discovered. Seven seeds receiving hits of HZE (high atomic number and high energy) particles from space were selected for further analyses and variable genomic polymorphisms were detected in all plants that developed from these seeds. Among them, the embryos of three seeds were hit at least once, and mutants with significant changes in agronomic traits were only found in later generations of these seeds. This result implies that the HZE particles of space are effective in inducing the changes of plant genome of inherited phenotypes.
  • DAI Quanlin, YUAN Jiangang, YANG Zhongyi, FANG Wei
    Pollution of agricultural land by heavy metals has imposed an increasingly serious risk to environmental and human health in recent years. Heavy metal pollutants may enter the human food chain through agricultural products and groundwater from the polluted soils. Progress has been made in the past decade on phytoremediation, a safe and inexpensive approach to remove contaminants from soil and water using plants. However, in most cases, agricultural land in China cannot afford to grow phytoremediator plants instead of growing crops due to food supply for the great population. Therefore, new and effective methods to decrease the risk of heavy metal pollution in crops and to clean the contaminated soils are urgently needed. If we can find crop germplasms (including species and varieties) that accumulate heavy metals in their edible parts, such as the leaves of vegetables or grains of cereals, at a level low enough for safe consumption, then we can grow these selected species or varieties in the lands contaminated or potentially contaminated by heavy metals. If we can find crop germplasms that take in low concentrations of heavy metals in their edible parts and high content of the metals in their inedible parts, then we can use these selected species or varieties for soil remediation. In this study, the feasibility of the method is assessed by analyzing Pb concentrations in edible and inedible parts of 25 varieties of maize (Zea mays) grown in Pb-contaminated soils. The soil concentrations of Pb were 595.55 mg/kg in the high Pb exposed treatment and 195.55 mg/kg in the control. The results showed that the Pb concentrations in different tissues were in the order of root>shoot ≈ leaf>grain. Compared with the control, the Pb concentrations in root, shoot and leaf were greatly increased under the high Pb exposed condition, while the increments of Pb concentration in grain were relatively lower. Under the high Pb exposure, the grain Pb concentrations of 12 varieties exceeded the maximal Pb limitation of the National Food Hygiene Standard of China (NFHSC) and were inedible. This indicates that there is a high Pb pollution risk for maize grown on Pb polluted sites. Although 22 of the 25 tested varieties had harvest loss under the highly Pb stressed condition, ranging from 0.86%–38.7% of the grain biomass acquired at the control, the average harvest loss of all the tested varieties was only 12.6%, which is usually imperceptible in normal farming practices. Therefore the risk of Pb pollution in maize products cannot be promptly noticed and prevented based only on the outcome of the harvest. However, we did find that 13 of the 25 tested varieties had grain Pb concentrations lower than the limitation of the NFHSC. It is, therefore, possible to reduce the pollution risk if these favorable varieties are used for maize production in Pb-contaminated or potentially contaminated agricultural lands. Pb concentrations in vegetative tissues (root, stem and leaf) were significantly correlated with each other, while Pb concentrations of each vegetative tissue were not significantly correlated with that of grain. Among the 25 tested varieties, some varieties had Pb concentrations in grain lower than (No.1 3 and No.6) or slightly above (No.4) the limitation of the NFHSC, while their Pb concentrations in the vegetative tissues were among the highest. When excluding these varieties, correlations between the Pb concentrations of grain and those of vegetative tissues of the rest of the tested varieties became highly significant. In addition, variety No.1 had the lowest harvest loss under high Pb exposed, and the highest Pb accumulation in vegetative tissues (51.69 mg/plant, 12 times as much as in the control). Similar features were also observed in varieties No.2, No.3 and No.6, which absorbed Pb for 36–42 mg/plant under high Pb exposed. We recommend these varieties of maize to be used for bioremediation of Pb contaminated soil and crop production at the same time.
  • LI Dongdong, HE Shaoheng
    Total proteins in the pollen of Humulus scandens Lour, one of the most popular aeroallergens in China, were analyzed by two-dimensional electrophoresis in the current study. The proteins were extracted by Trichloracetic acid (TCA) method, and then separated by isoelectric focusing as the first dimension and SDS-PAGE as the second dimension. The spots of proteins were visualized by staining with Coomassie Brilliant Blue. After analysis with software (ImageMaster 2D), 122 different proteins were detected; isoelectric point (pI), Molecular weight (MW) and relative volume of each protein in the pollen were also discovered. This is the first high-resolution, two-dimensional protein map of the pollen of Humulus scandens Lour in China. Our finding has built a solid foundation for identification, characterization, gene cloning and standardization of allergenic proteins in the pollen of Humulus scandens Lour for further studies.
  • WU Junlin, GAO Xuehong, ZHANG Sheqi
    The germination of laser-irradiated Chinese pine seeds was carried out under drought stress. The activities of superoxide dismutase (SOD) and peroxidase (POD), and the content of malondialdehyde (MDA) were determined. Results showed notably increased germination percentage, root length, vitality index and fresh weight. The SOD and POD protective enzyme system activity of the Chinese pine seedlings obviously rose. It can be concluded that the germination and juvenile resistance of Chinese pine seeds under drought stress are enhanced after laser processing.
  • MA Wenhong
    The relationship between plant species richness and primary productivity has long been a central topic in biodiversity research. In this paper, we examine the relationship between species richness and productivity in four typical grasslands of Northern China at different spatial scales. At the community scale, a positive correlation was found for six of seven communities. A unimodal pattern was found only for one community (Stipa glareosa community), while at a large scale (vegetation type or landscape/region), the relationship was also found significantly positive. Species richness ranged from 4 to 35 species, and community aboveground productivity from 13 to 368 g · m-2 · a-1. The highest species richness and aboveground productivity were found in alpine meadow, followed by meadow steppe, typical steppe and desert steppe.
  • ZHAO Liang, XU Shixiao, ZHAO Xinquan, GU Song, LI Yingnian, TANG Yanhong, DU Mingyuan, YU Guirui
    Carbon dioxide fluxes of Kobresia humilis and Potentilla fruticosa shrub meadows, two typical ecosystems in the Qinghai-Tibet Plateau, were measured by eddy covariance technology and the data collected in August 2003 were employed to analyze the relations between carbon dioxide fluxes and environmental factors of the ecosystems. August is the time when the two ecosystems reach their peak leaf area indexes and stay stable, and also the period when the net carbon absorptions of Kobresia humilis and Potentilla fruticosa shrub meadows reach 56.2 g C · m-2 and 32.6 g C · m-2, with their highest daily carbon dioxide absorptions standing at 12.7 ?mol · m-2 · s-1 and 9.3 ?mol · m-2 · s-1, and their highest carbon discharges at 5.1 ?mol · m-2 · s-1 and 5.7 ?mol · m-2 · s-1, respectively. At the same photosynthetic photo flux densities (PPFD), the carbon dioxide-uptake rate of the Kobresia humilis meadow is higher than that of the Potentilla fruticosa shrub meadow; where the PPFD are highe r than 1,200 μmol · m-2 · s-1. The carbon dioxide uptake rates of the two ecosystems declined as air temperature increased, but the carbon dioxide uptake rate of the Kobresia humilis meadow decreased more quickly (–0.086) than that of the Potentilla fruticosa shrub meadow (–0.016). Soil moistures exert influence on the soil respirations and this varies with the vegetation type. The daily carbon dioxide absorptions of the ecosystems increase with increased diurnal temperature differences and higher diurnal temperature differences result in higher carbon dioxide exchanges. There exists a negative correlation between the vegetation albedos and the carbon dioxide fluxes.
  • HAN Mei, JI Chengjun, ZUO Wenyun, HE Jinsheng
    The anatomical features of leaves in 11 species of plants grown in a temperature gradient and a temperature+CO2 gradient were studied. The palisade parenchyma thickness, the spongy parenchyma thickness and the total leaf thickness were measured and analyzed to investigate the effects of elevated temperature and CO2 on the anatomical characteristics of the leaves. Our results show that with the increase of temperature, the leaf thickness of C4 species increased while the leaf thickness of C3 species showed no constant changes. With increased CO2, seven out of nine C3 species exhibited increased total leaf thickness. In C4 species, leaf thickness decreased. As for the trend on the multi-grades, the plants exhibited linear or non-linear changes. With the increase of temperature or both temperature and CO2 for the 11 species investigated, leaf thickness varied greatly in different plants (species) and even in different branches on the same plant. These results demonstrated that the effect of increasing CO2 and temperature on the anatomical features of the leaves were species-specific. Since plant structures are correlated with plant functions, the changes in leaf anatomical characteristics in elevated temperature and CO2 may lead to functional differences.
  • CHANG Chongyan, CHEN Xiaoduan, LIU Jinying, ZHANG Zhengwang, SUN Quanhui
    The eggshell of Reeve’s pheasant (Syrmaticus reevesii) collected from the Dongzhai National Nature Reserve in Henan Province, China was studied. By using scanning electron microscopy and inductively coupled plasma (ICP) spectrometry, the ultrastructure and elemental composition of the eggshell was determined. The study showed that the average thickness of the surface layer of crystals, the palisade and cone layer, and the eggshell membrane were 20.8, 220.8 and 62.5 ?m, respectively, accounting for 6.8%, 72.6% and 20.6% of the total thickness of the eggshell. There were many vesicular holes in the palisade layer with an average diameter of 0.32&pllusmn;0.08 μm (n = 30). The function of these holes might be significant to air exchange. The shape of the eggshell pore on the surface layer of crystals is round or elliptical. The fracture surface of the pore is funnel-shaped. Some granules filled the upper part of the eggshell pores. The content of 21 elements in the eggshell of wild and captive Reeve s pheasants was compared and presented. It indicated that among the elements that made up the eggshell of the wild pheasant, the content of Ca, Mg, P and S was much higher, ω⟩1 mg/g, with ω (Ca) being higher than 40% of the eggshell. The contents of Na, Si, Sr, K and Al were ω=0.1–1 mg/g, while Fe, Zn, Pb, Mn, Cu, V and Ti had lower concentrations (ω = 1–100 μg/g). The ω of Ni, Cr, Co, Se, Cd were lower than 1 μg/g. The elemental composition in the eggshell of the captive Reeve s pheasant kept in the Dongzhai National Natural Reserve was significantly different from that of the wild species, with a difference of over 20% on S, Cu, Fe, Al, Mn, Si, Sr, Se and Cr. The lower intake of Fe, Mn, Si and Sr on the one hand and the higher intake of S, Cu, Al and Cr on the other hand might be responsible for the low fertility of captive Reeve’s pheasants in the Dongzhai National Nature Reserve. In order to ensure that the pheasants are receiving the proper amount of nutrition and to improve their breeding success, the amount of certain elements in the food should be adjusted.
  • WANG Ning, ZHANG Yanyun, ZHENG Guangmei
    The home ranges of the Narcissus Flycatcher (Ficedula narcissina elisae) and the Yellow-rumped Flycatcher (F. zanthopygia) are measured by radio telemetry in a subalpine forest near Beijing, China. The home range is calculated by 100% Minimum Convex Polygon (MCP), and the area varies from 2,000 to 5,000 m2. The majority of flycatchers can be found in the bottom of valleys and the underside of mountains. It is fairly rare for both Flycatcher species to leave their nests more than 70 m. Individuals of the species in pair-banding and nest-detecting periods have larger home ranges than those in incubation and rearing periods. The levels of canopy coverage in the home ranges of Narcissus Flycatchers are significantly higher than that of Yellow-rumped Flycatchers. There are also more tall trees and stumps in the home ranges of Narcissus Flycatchers than in that of Yellow-rumped Flycatchers. The dominant tree species in the home ranges of Narcissus Flycatchers is Dahurian Birch (Betula dahurica), whereas Manchurian Walnut (Juglans mandshurica) is the dominant tree species in the home ranges of Yellow-rumped Flycatchers.
  • WANG Lihong, LIN Liu, ZHANG Li, HE Qian, ZHANG Jinguo
    Thirty-seven wild plants as food for Asian elephants in the field in Simao, Yunnan province, China and five cultivated plants as food for captive elephants in the Beijing Zoo were collected and analyzed for their main nutrient components. Protein, fat, fiber, dry material, ash as well as major microelements: calcium, kalium, zincum, sodium in the food were analyzed by standard methodology. No significant differences were found between the wild plants taken in the field and forage provided in captivity. However, the calcium content in the forage is significantly less than the average of those in the wild plants. It is suggested that the increase in calcium intake may contribute to the relief of low plasma calcium diseases of elephants in captivity.
  • WANG Benyang, YU Shixiao, WANG Yongfan
    Direction-dependence, or anisotropy, of spatial distribution patterns of vegetation is rarely explored due to neglect of this ecological phenomenon and the paucity of methods dealing with this issue. This paper proposes a new approach to anisotropy analysis of spatial distribution patterns of plant populations on the basis of the data resampling technique (DRT) combined with Ripley s L index. Using the ArcView Geographic Information System (GIS) platform, a case study was carried out by selecting the population of Pinus massoniana from a needle- and broad-leaved mixed forest community in the Heishiding Nature Reserve, Guangdong Province. Results showed that the spatial pattern of the P. massoniana population was typically anisotropic with different patterns in different directions. The DRT was found to be an effective approach to the anisotropy analysis of spatial patterns of plant populations. By employing resampling sub-datasets from the original dataset in different directions, we could overcome the difficulty in the direct use of current non-angular methods of pattern analysis.
  • LIU Hailong, TANG Jiling
    The types of myocardial ischemia can be revealed by electrocardiographic (ECG) ST segment. Effective measurement and electrocardiographic analysis of ST as well as calculation of displacement and shape change of ST segment can help doctors diagnose coronary heart disease and myocardial ischemia, especially for asymptomatic myocardial ischemia. Therefore, it is a very important subject in clinical practice to measure and classify the ECG ST segment. In this paper, we introduce a computerized automatic identification method of the electrocardiographic ST segment shape with radial basis function neural network based on adaptive fuzzy system, which has a better effect than other methods. It helps to analyze the reason of the ST segment change and confirm the position of myocardial ischemia, and is useful for doctor diagnosis.