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Effect of hormonal status and metabolic changes of restricted ewes during late pregnancy on their fetal growth and development

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Science china(Life Sciences) 2007年第6期50卷 766-772页

作者： GAO Feng1, HOU XianZhi1 & LIU YingChun2 1 college of Animal Science and Animal Medicine, inner mongolia agricultural university, huhhot 010018, china 2 college of biotechnology and bioengineering, inner mongolia agricultural university, huhhot 010018, china college of Animal Science and Animal Medicine Inner Mongolia Agricultural University Huhhot China college of biotechnology and bioengineering Inner Mongolia Agricultural University Huhhot China

This study investigated the effects of hormonal status and metabolic changes of restricted ewes during late pregnancy on the ovine fetus growth and development. One hundred mongolian ewes, synchro- nized for oestrus and mated, were divided into three groups and offered 0.175 MJME·kgw-0.75·d-1 (Re- stricted Group 1, RG1), 0.33 MJME·kgw-0.75·d-1 (Restricted Group 2, RG2) and ad libitum access to feed (Control Group, CG) during their late pregnancy respectively. The results suggested that with the sup- ply of exogenous energy decreasing during late pregnancy, maternal body weight and net body weight loss in RG2 and RG1 were lower than those of CG (P2 and RG1 tended to be lower than those of CG (P>0.05), but the GH concentrations in RG2 and RG1 were enhanced and there was significant difference between RG1 and CG on d 120 of gesta- tion (P2 and RG1 was decreased throughout the feed restriction period, and the differences were observed between RG1 and CG on d 120 of gestation (P2 tended to increase, but there was no significant difference (P>0.05). However, the NEFA and FAA concentrations of ewes in RG1 were reduced from d 90 to d 120 of gestation, then enhanced from d 120 to d 140 of gestation. During the late pregnancy, with the supply of nutrition decreasing, the negatively physiological and biochemical maternal reactions to restriction became worse, which sig- nificantly reduced the average lamb birth weight and daily growth rate of fetus in RG2 (P<0.05) and RG1 (P<0.01).

关键词： late pregnancy, restricted ewes, fetus, growth and development

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Integrating MODFLOW and GIS technologies for assessing impacts of irrigation management and groundwater use in the Hetao Irrigation District,Yellow River basin

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Science china(Technological Sciences) 2009年第11期52卷 3257-3263页

作者： XU Xu1,2, HUANG GuanHua1,2 & QU ZhongYi3 1 Center for Agriculture Water Research, china agricultural university, Beijing 100083, china 2 Chinese-Israeli International Center for Research and Training in Agriculture, china agricultural university, Beijing 100083, china 3 Water Conservancy and Civil Engineering college, inner mongolia agricultural university, Hohhot 010018, china Center for Agriculture Water Research China Agricultural University Beijing China Chinese-Israeli International Center for Research and Training in Agriculture China Agricultural University Beijing China Water Conservancy and Civil Engineering college Inner Mongolia Agricultural University Hohhot China

Due to severe water scarcity, water resources used in agricultural sector have been reduced markedly in Hetao irrigation district. Application of water-saving practices (WSPs) is required for the sustainable agricultural development. The human activities including WSPs and increase of groundwater abstraction can lower down the groundwater table, which is helpful to the salinity control. Meanwhile, an excessively large groundwater table depth may result in negative impact on crop growth and fragile ecological environment. In this paper, the Jiefangzha irrigation system in Hetao irrigation district was selected as a typical area, a groundwater flow model based on ArcInfo Geographic Information System (GIS) was developed and implemented to quantify the effect of human activities on the groundwater system in this area. The preand post-processing of model data was performed efficiently by using the available GIS tools. The time-variant data in boundary conditions was further edited in Microsoft Excel with programs of Visual Basic for Application (VBA). The model was calibrated and validated with independent data sets. Application of the model indicated that it can well describe the effect of human activities on groundwater dynamics in Jiefangzha irrigation system.

关键词： groundwater flow modeling MODFLOW GIS water-saving practices irrigation district

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Roles of Salicylic Acid-responsive Cis-acting Elements and W-boxes in Salicylic Acid Induction of VCH3 Promoter in Transgenic Tobaccos

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Acta Biochimica et Biophysica Sinica 2006年第1期38卷 46-52页

作者： Hai-Yan LI~(1,2),Wei WEI~(2&),and Yu LI~(1*) ~1 Institute of Mycology,Jilin agricultural university,Changchun 130118,china ~2 college of biotechnology,Jilin agricultural university,Changchun 130118,china Institute of Mycology Jilin Agricultural University Changchun 130118 China college of biotechnology Jilin Agricultural University Changchun 130118 China

A salicylic acid (SA)-inducible VCH3 promoter was recently identified from grapevine (Vitisarnurensis) that contains two inverse SA-responsive cis-acting elements and four *** furtherdemonstrate the roles of these elements,four fragments with lengths from-1187,-892,-589,-276 to+7 bp were fused with the β-glucuronidase (GUS) reporter géne and transferred to Nicotiana tobacum,together with another four VCH3 promoter fragments with mutation in the two inverse *** functions,of each promoter fragment were-examined by analysis of GUS activity in thetransgenic tobacco root treated with *** GUS activity was shown in the roots of transgenictobaccos with the VCH3 (-1187)-GUS construct containing two SA-responsive cis-acting elements andfour ***,GUS activity directed by the VCH3 (-892)-GUS construct,containing one SA cis-acting element and four W-boxes,was reduced by up to 35% compared with that in tobaccos transformedwith the VCH3 (-1187)-GUS construct,indicating that the SA cis-acting element plays an important role inSA induction of the VCH3 *** the m2VCH3 (-1187)-GUS nor the mVCH3 (-892)-GUSconstruct,with mutation on the SA-responsive elements,abolished the expression of GUS activity,demon-strating that the W-boxes in the VCH3 promoter are also involved in SA *** arialysis ofGUS activity directed by each of the eight VCH3 promoter fragments showed that GUS was expressedspecifically in vascular *** was concluded that both the SA-responsive cis-acting elements and the W-boxes are important for the SA induction of the VCH3 *** promoter might have a potential usein plant genetic engineering.

关键词： VCH3 promoter salicylic acid(SA)-responsive cis-acting element W-box site-directed mutagenesis SA induction transgenic tobacco

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Phototoxic effect of UVR on wild type, ebony and yellow mutants of Drosophila melanogaster: Life Span, fertility, courtship and biochemical aspects

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Science china(Life Sciences) 2008年第10期51卷 885-893页

作者： WANG ZhePeng1,2, LIU RuiFang2, WANG AnRu3, DU LiLi1 & DENG XueMei1 1 college of Animal Science and Technology, china agricultural university, Beijing 100094, china 2 Vocational and Technologic college, inner mongolia Agriculture university, Baotou 014109, china 3 college of Veterinary Medicine, china agricultural university, Beijing 100094, china college of Animal Science and Technology China Agricultural University Beijing China Vocational and Technologic college Inner Mongolia Agriculture University Baotou China college of Veterinary Medicine China Agricultural University Beijing China

Melanin plays an important role in protecting organisms from ultraviolet radiation (UVR). Therefore, it is possible that differently colored strains can show different sensitivities to UVR. In the present work, life span, fertility and courtship behavior of wild type (w), ebony (e) and yellow (y) strains of Drosophila melanogaster were studied to evaluate their sensitivity to ultraviolet (UV). Because a range of photo- toxic effects of UVR are mediated through generation of free radicals, levels of free radicals, lipid per- oxide (malondialdehyde, MDA) and superoxide dismutase (SOD) activity of three strains were examined to indicate their antioxidant defending ability and oxidative status. It was shown that w always had the highest lifespan and fertility not only in the control but also in UV-exposed groups. Moreover, lifespan and fertility of e were significantly higher (P2) effect on the SOD activities. After pooling data from the control and UV-exposed groups, we found that w had a significantly (P0.05). MDA levels were increased in the UV dose-dependent manner (P=0.0495). In con- clusion, our results suggested that UVR can decrease life span and fertility of flies and do harm to courtship, which may be due to oxidative damage to flies tissues (e.g. central nervous system) induced by free radicals. w had the highest tolerance to UVR, which may be ascribed to its advantage of survival under the natural condition and at high level of SOD activity. Then differences of pigment between e and y in absorbing UV, shielding agai

关键词： ultraviolet radiation Drosophila melanogaste free radicals pigment

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Design and Expression of a Synthetic phyC Gene Encoding the Neutral Phytase in Pichia pastoris

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Acta Biochimica et Biophysica Sinica 2006年第11期38卷 803-811页

作者： Li-Kou ZOU~(1,3) Hong-Ning WANG~(2,1*) Xin PAN~4 Tao XIE~1 Qi WU~5 Zi-Wen XIE~1 Wan-Rong ZHOU~1 1 Laboratory of Veterinary and biotechnology,Sichuan agricultural university,Ya'an 625014,china 2 Sichuan university bioengineering Research Center for Animal Disease Prevention and Control,Chengdu 610065,china 3 Faculty of Environment and Resource of Dujiangyan Campus,Sichuan agricultural university,Dujiangyan 611830,china 4 college of Earth Science,Chengd university of Technology,Chengdu 610059,china 5 college of Life Science,Sichuan agricultural university,Ya'an 625014,china Laboratory of Veterinary and biotechnology Sichuan Agricultural UniversityYa'an 625014 China Faculty of Environment and Resource of Dujiangyan Campus Sichuan Agricultural UniversityDujiangyan 611830 China Sichuan university bioengineering Research Center for Animal Disease Prevention and Control Chengdu 610065 China college of Earth Science Chengdu University of TechnologyChengdu 610059 China college of Life Science Sichuan Agricultural UniversityYa'an 625014 China

The 1074-bp phyCs gene （optimized phyC gene） encoding neutral phytase was designed andsynthesized according to the methylotrophic yeast Pichia pastoris codon usage bias without altering theprotein *** expression vector,pP9K-phyCs,was linearized and transformed in *** of total extracellular phytase activity was 17.6 U/ml induced in Buffered Methanol-complex Medium（BMMY） and 18.5 U/ml in Wheat Bran Extract Induction （WBEI） medium at the flask scale,respectively,improving over 90 folds compared with the wild-type *** enzyme showed temperature optimumof 70℃ and pH optimum of *** enzyme activity retained 97% of the relative activity afterincubation at 80℃ for 5 *** of the heavy glycosylation the expressed phytase had a molecularsize of approximately 51 *** deglycosylation by endoglycosylase H （EndoH_f）,the enzyme had anapparent molecular size of 42 *** property and thermostability was affected by the glycosylation.

关键词： design expression synthetic phyC gene neutral phytase Pichia pastoris

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Satellite RNA-mediated Reduction of Cucumber Mosaic Virus Genomic RNAs Accumulation in Nicotiana tabacum

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Acta Biochimica et Biophysica Sinica 2007年第3期39卷 217-223页

作者： Qiansheng LIAO~(1,2) Liping ZHU~2 Zhiyou DU~2 Rong ZENG~(2,3) Junli FENG~2 Jishuang CHEN~(1,2*) 1 college of Life Sciences,Zhejiang university,Hangzhon 310029,china 2 Institute of bioengineering,Zhejiang Sci-Tech university,Hangzhou 310018,china 3 college of Biological Safety Technology Hunan agricultural university,Changsha 410128,china college of Life Sciences Zhejiang UniversityHangzhou 310029 China Institute of bioengineering Zhejiang Sci-Tech UniversityHangzhou 310018 China college of Biological Safety Technology Hunan Agricultural UniversityChangsha 410128 China

Satellite RNAs(satRNAs)are molecular parasites that interfere with the pathogenesis of thehelper *** this study,the relative accumulation of cucumber mosaic virus(CMV)-Fny genomicRNAs with or without satRNAs were quantitatively analyzed by real-time *** results showed thatsatRs apparently attenuated the symptoms of CMV-Fny on Nicotiana tabacum by depressing the accumu-lation of CMV-Fny genomic RNAs,tested as open reading *** accumulation of CMV-Fny 1a,2a,2b,3a,and CP genes was much higher than that of CMV-Fny with satRs added(CMV-Fsat),at differentinoculation ***-FnyΔ2b,in which the complete 2b gene and 41 amino acids at the C-terminal of the2a gene were deleted,caused only a slight mosaic effect on *** seedlings,similar to that of CMV-Fsat,but the addition of satRs to CMV-FnyΔ2b showed further decrease in the accumulation of CMV-FnyΔ2b genomic *** results indicated that the attenuation of CMV,by adding satRs or deleting the2b gene,was due to the low accumulation of CMV genomic RNAs,and that satRNA-mediated reduction ofCMV genomic RNAs accumulation in *** was possibly related to the 2b gene.

关键词： cucumber mosaic virus satellite RNA deletion of 2b gene relative accumulation

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Migration and population genetics of the grain aphid Macrosiphum miscanti (Takahashi) in relation to the geographic distance and gene flow

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Progress in Natural Science:Materials International 2005年第11期15卷 1000-1004页

作者： GUO Wei, SHEN Zuorui, LI Zhihong and GAO Lingwang (college of Agronomy and biotechnology, china agricultural university, Beijing 100094, china) college of Agronomy and biotechnology China Agricultural University Beijing 100094 China

The population genetics of the grain aphid Macrosiphum miscanti (Takahashi) is analyzed by microsatellite markers. Samples collected from 15 locations in china have been examined at 5 polymorphic microsatellite loci. Overall, genetic diversity displays a relation between the migration and gene flow in the grain aphid; a free and frequent gene flow is found in the eastern populations, and gene isolation occurs in the two western populations, especially Datong population and Guiyang population. The natural barriers may present an insurmountable obstacle preventing gene flow and aphid migration. However, a spatial genetic differentiation between populations is correlated with their geographical separation, indicating the geographic differentiation may play an important role in shaping the genetic structure of M. miscanti populations. In addition, most populations of grain aphids are out of Hardy-Weinberg equilibrium and there is het-erozygote deficit. Based on F statistics, the average genetic differentiation among different geographical populations is relatively low. It seems that the long distance migration of the grain aphid may enhance gene flow and decrease genetic differentiation among different populations .

关键词： Macrosiphum miscanti microsatellite gene flow migration.

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Evaluation of genetic diversity and relationships within and between two breeds of duck based on microsatellite markers

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Progress in Natural Science:Materials International 2009年第11期19卷 1581-1586页

作者： Fei Wu~a,Yinghua Huang~a,Ying Ma~b,Shengqiang Hu~c,Jinping Hao~c,Ning Li~a a State Key Laboratory for Agrobiotechnology,china agricultural university,Beijing 100193,china b college of Animal Science and Veterinary Science,inner mongolia agricultural university,Hohhot 010018,china c Gold Star Duck Production Ltd.,Beijing 100076,china State Key Laboratory for Agrobiotechnology China Agricultural University Beijing 100193 China college of Animal Science and Veterinary Science Inner Mongolia Agricultural University Hohhot 010018 China Gold Star Duck Production Ltd. Beijing 100076 China

The genetic diversity of two natural populations(M,N) of Beijing duck(Anas platyrhynchos) and 11 artificially selected lines of Beijing duck(A,B,E-L,O) from china Gold Star Duck Production Ltd.,along with two Cherry Valley duck lines(C and D) from the British Cherry Valley Livestock Division,was evaluated using 18 microsatellite markers covering 16 linkage groups.A phylogenetic tree of the 15 populations of duck,formed of four main branches,was constructed from Nei’s DAgenetic *** mean genetic differentiation index(FST) in all loci,Nei’s standard genetic distance(Ds),and the genetic distance DAbetween the Beijing duck and the Cherry Valley duck were 0.075,0.143 and 0.142,*** results demonstrated a high degree of genetic similarity between the two breeds and supported the hypothesis that the Cherry Valley duck was derived from the Beijing *** FSTmatrix of seven clusters of Beijing duck suggested that the efficiency of selection was not significant to some extent and should be supplemented by marker -assisted selection.

关键词： Duck Microsatellite marker Genetic diversity Genetic distance

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Synergy between Cucumber Mosaic Virus and Zucchini Yellow Mosaic Virus on Cucurbitaceae Hosts Tested by Real-time Reverse Transcription-Polymerase Chain Reaction

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Acta Biochimica et Biophysica Sinica 2007年第6期39卷 431-437页

作者： Rong ZENG~(1,2#), Qiansheng LIAO~(2#), Junli FENG~2, Dingjun LI~1, and Jishuang CHEN~(2*) 1 college of Bio-Safety Science Technology, Hunan agricultural university, Changsha 410128, china, 2 Institute of bioengineering, Zhejiang Sci-Teeh university, Hangzhou 310018, china college of Bio-Safety Science Technology Human Agricultural UniversityChangsha 410128 China Institute of bioengineering Zhejiang Sci-Tech UniversityHangzhou 310018 China

Cucumber mosaic virus (CMV) and zucchini yellow mosaic virus (ZYMV) are two principal viruses infecting cucurbitaceous crops, and their synergy has been repeatedly observed. In our present work, a real-time reverse transcription-polymerase chain reaction procedure was established to study the accumulation kinetics of these two viruses in single and combined infections at the molecular level. The accumulations of open reading frames (ORFs) for 1a, 2a, 3a and coat protein (CP) of CMV and CP of ZYMV were tested. In the single infection, CMV-Fny ORFs accumulated to their maxima in cucumber or bottle gourd at 14 d post-inoculation (dpi), and gradually declined thereafter. ZYMV-SD CP ORF reached maximal accumulation at 14 and 28 dpi on cucumber and bottle gourd, respectively. However, when coinfected with CMV-Fny and ZYMV-SD, the maximal accumulation levels of all viral ORFs were delayed. CMV-Fny ORFs reached their maxima at 21 dpi on both hosts, and ZYMV-SD CP ORF reached maximal accumulation at 21 and 28 dpi on cucumber and bottle gourd, respectively. Generally, the accumulation levels of CMV-Fny ORFs in the co-infection were higher than those in the single infection, whereas the accumulation of ZYMV-SD CP ORF showed a reverse result.

关键词： cucumber mosaic virus genornic RNA real-time RT-PCR relative quantification synergy zucchini yellow mosaic virus

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Ramet population ecology of Panicum virgatum in the field–Competitively random growth of ramets and foraging behavior of ramet populations

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Progress in Natural Science:Materials International 2008年第7期18卷 901-906页

作者： Xinguo Yang a,*, Tianlong Wu b, Xu Chengb a college of Resources and Environmental Sciences, china agricultural university, Beijing 100193, P.R. china b college of Agriculture and biotechnology, china agricultural university, Beijing 100193, P.R. china college of Resources and Environmental Sciences China Agricultural University Beijing 100193 P.R. China college of Agriculture and biotechnology China Agricultural University Beijing 100193 P.R. China

The authors investigated the heterogeneous size patterns and dynamic growth of the ramet population of Panicum virgatum, a clonal caespitose plant, limited to the space occupied by a ramet bunch and the time of the ramet yearly life cycle, to understand the ecology of clonal caespitose plants in the field, where the ramet bunch generally consisted of more than one genet. Dynamic life tables for ramet populations were established by the replacement of living ramets at the present time with "dead" ones in past time. These tables revealed stable coexisting patterns of isometric and allometric growing processes of ramets in mass and height respectively, which approximately followed the historic trajectory of a density-independent population. The ecology of clonal caespitose plants is further discussed based on the competitively random growth of ramet individuals, including the scale of foraging behavior. In the field, the ramet population ecol- ogy of switchgrass may be a statistical result of competitively random growth of ramet individuals. The foraging behavior of a ramet population could then be presented as a process in which ramet individuals competed with each other for light and grew randomly, while at the same time a relatively stable dynamic growth pattern was apparent at the level of the ramet population, and the functional leaves were placed properly in time and space.

关键词： Caespitose clone Ramet population Panicum virgatum Life table Phenotypic plasticity Foraging behavior

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