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Effects of chemical activation and season on birth efficiency of cloned pigs

Science china(Life Sciences) 2009年第7期52卷 657-664页

作者： MA YuFang1,2,LI Yan3,WEI HengXi1,LI QiuYan3,FANG Rui1,ZHAO Rui3,ZHANG Kun1,XUE Kai1,LOU YanKun1,DAI YunPing3,LIAN LinSheng2 & LI Ning1 1 State Key Laboratory of Agrobiotechnology,College of Biological Sciences,china Agricultural University,beijing 100193,china 2 College of Animal Science and Technology,china Agricultural University,beijing 100193,china 3 beijing genprotein biotechnology company,beijing 100193,china State Key Laboratory of Agrobiotechnology College of Biological Sciences China Agricultural University Beijing China College of Animal Science and Technology China Agricultural University Beijing China beijing genprotein biotechnology company Beijing China

The effects of chemical activation on birth efficiency of cloned pigs were studied by investigating the developmental process from porcine oocyte activation to birth of cloned *** different activation methods were used:(i) Electroporation(Ele);(ii) Ele followed by incubation with 6-dimethylaminopurine(6-DMAP);and(iii) Ele followed by a treatment with cycloheximide(CHX).In experiment 1,the rates of cleavage,developmental rates and cell number of porcine parthenogenetic(PA) embryos were investigated in the three treatment *** experiment 2,NT embryos produced by the three different activation treatments were compared for the rates of cleavage,development and cell ***,the effects of Ele and Ele+CHX activation methods on birth efficiency of cloned pigs were *** activated oocytes treated by combination activation generally showed a higher(P<0.05) blastocyst rate and produced more expanded blastocysts than oocytes activated with *** rates of cleavage and total cell number of parthenotes were not significantly *** embryos activated with 6-DMAP developed into blastocyst and expanded blastocyst stages at a significantly(P<0.05) higher rate than those treated with Ele,but the developmental capability was dramatically decreased in NT *** the CHX activation method,the NT embryo blastocyst rate was substantially(P<0.05) increased although the production of expanded blastocysts was not significantly different from that by the other two *** birth rate of cloned pigs increased in the CHX group,though the rate was not significantly different from *** effects of season on developmental rate of the porcine PA embryos and birth rate of cloned pigs were also examined in our *** oocytes collected in the spring had higher developmental capabilities than those collected in the ***,no difference in birth rate of the cloned pigs was found between the oocytes collected in the two *** re

关键词： parthenogenetic activation chemical activation nuclear transfer pig season

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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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Efficient production of omega-3 fatty acid desaturase (sFat-1)-transgenic pigs by somatic cell nuclear transfer

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Science china(Life Sciences) 2010年第4期53卷 517-523页

作者： PAN DengKe1, ZHANG Li1, ZHOU YanRong2, FENG Chong1, LONG Chuan1, LIU Xiao1, WAN Rong3, ZHANG Jian3, LIN AiXing3, DONG EnQiu4, WANG ShuChen4, XU HouGang4 & CHEN HongXing2 1 Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, beijing 100193, china 2 beijing Institute of biotechnology, beijing 100071, china 3 china Agricultural University, beijing 100193, china 4 Yutian Breeding Swine Farms, Yutian 064104, china Institute of Animal Sciences Chinese Academy of Agricultural Sciences Beijing China beijing Institute of biotechnology Beijing China china Agricultural University Beijing China Yutian Breeding Swine Farms Yutian China

Omega-3(ω-3) fatty acid desaturase transgenic pigs may improve carcass fatty acid composition. The use of transgenic pigs is also an excellent large animal model for studying the role of ω-3 fatty acids in the prevention and treatment of coronary heart disease and cancer. Transgenic pigs carrying synthesized fatty acid desaturase-1 gene (sFat-1) from Caenorhabditis briggsae by somatic cell nuclear transfer (SCNT) were produced for the first time in china. Porcine fetal fibroblast cells were transfected with a sFat-1 expression cassette by the liposome-mediated method. Transgenic embryos were reconstructed by nuclear transfer of positive cells into enucleated in vitro matured oocytes. A total of 1889 reconstructed embryos were transferred into 10 naturally cycling gilts. Nine early pregnancies were established, 7 of which went to term. Twenty-one piglets were born. The cloning efficiency was 1.1% (born piglets/transferred embryos). The integration of the sFat-1 gene was confirmed in 15 live cloned piglets by PCR and Southern blot except for 2 piglets. Expression of the sFat-1 gene in 12 of 13 piglets was detected with RT-PCR. The data demonstrates that an efficient system for sFat-1 transgenic cloned pigs was developed, which led to the successful production of piglets expressing the sFat-1 gene.

关键词： sFat-1 nuclear transfer ovulation status transgenic pig

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Reappraisal of Microtropis macrocarpa C.Y. Cheng & T.C. Kao(Celastraceae),a critically endangered species endemic to Yunnan, china

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Journal of Systematics and Evolution 2009年第3期47卷 220-225页

作者： Qin-Wen LIN Zhi-Xiang ZHANG (College of Biological Sciences and biotechnology, beijing Forestry University, beijing 100083, china) (College of Biological Sciences and biotechnology Beijing Forestry University Beijing 100083 China)

Microtropis macrocarpa C.Y. Cheng & T.C. Kao has been treated as a synonym of Microtropis macrophylla Merr. & Freeman in most taxonomic reports in china. According to our study, M. macrocarpa is an independent species endemic to Yunnan, china. Microtropis macrophylla and Microtropis pachyphylla Merr. & Freeman should be treated as synonyms of Microtropis longifolia Wall. ex Kurz. M. macrocarpa is also identified as a critically endangered species, CR B1ab (i,ii,iii,v), based on the IUCN Red List Categories and Criteria. The foliar surface, anther and pollen structures were also observed with a scanning electron microscope.

关键词： Celastraceae foliar epidermis IUCN Red List Microtropis pollen.

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A measurement error model for microarray data analysis

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Progress in Natural Science:Materials International 2005年第7期15卷 614-620页

作者： ZHOU Yiming and CHENG Jing ( Department of Biological Sciences and biotechnology, Tsinghua University, beijing 100084, china State Key Laboratory of Biomembrane and Membrane biotechnology, Tsinghua University, beijing 100084, china National Engineering Research Center for beijing Biochip Technology, 18 Life Science Parkway, beijing 102206, china) Department of Biological Sciences and biotechnology Tsinghua University Beijing 100084 China State Key Laboratory of Biomembrane and Membrane biotechnology Tsinghua University Beijing 100084 China National Engineering Research Center for beijing Biochip Technology 18 Life Science Parkway Beijing 102206 China

Microarray technology has been widely used to analyze the gene expression levels by detecting fluorescence intensity in a high throughput fashion. However, since the measurement error produced from various sources in microarray experiments is heterogeneous and too large to be ignored, we propose here a measurement error model for microarray data processing, by which the standard deviation of the measurement error is demonstrated to be linearly increased with fluorescence intensity. A robust algorithm, which estimates the parameters of the measurement error model from a single microarray without replicated spots, is provided. The model and algorithm for estimating of the parameters from a given data set are tested on both the real data set and the simulated data set, and the result has been proven satisfactory. And, combining the measurement error model with traditional Z-test method, a full statistical model has been developed It can significantly improve the statistical inference for identifying differentially expressed genes.

关键词： microarray measurement error model parameter estimation differentially expressed genes.

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Structure and regulatory function of plant transcription factors

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Chinese Science Bulletin 2001年第4期46卷 271-278页

作者： LIU Qiang, ZHANG Guiyou & CHEN ShouyiDepartment of Biological Science and biotechnology, Tsinghua Univorsity, beijing 100084, china Department of Biological Science and biotechnology, State Laboratory of Biomembrane and Membrane biotechnology, Tsinghua University, beijing 100084, china Institute of Genetics, Chinese Academy of Sciences, beijing 100101, china Department of Biological Science and biotechnology Tsinghua University Beijing China Department of Biological Science and biotechnology State Laboratory of Biomembrane and Membrane Biotechnology Tsinghua University Beijing China Institute of Genetics Chinese Academy of Sciences Beijing China

The expression of inducible genes in plants is regulated by specific transcription factors at the transcrip-tional level. A typical transcription factor usually contains a DNA-binding domain, a transcription regulation domain, a dimerization site and a nuclear localization domain. These functional domains define the characteristic, localization and regulatory role of a transcription factor. Transcription factors recognize and bind to specific cis-acting elements or interact with other proteins, and then activate or repress the transcription of target genes by their functional domains. In recent years, elucidation on the structure and function of transcription factors has become an important subject in plant molecular biology.

关键词： transcription factor DNA-binding domain cis-acting element.

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Effect of TGF-β/Smad signaling pathway on lung myofibroblast differentiation

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Acta Pharmacologica Sinica 2007年第3期28卷 382-391页

作者： Li GU~2 Yuan-jue ZHU~(2,4) Xiao YANG~3 Zi-Jian GUO~2 Wen-bing XU~2 Xin-lun TIAN~22 Department of Pulmonary Medicine,Peking Union Medical College Hospital,Chinese Academy of Medical Sciences,beijing 100071 china 3 Genetic Laboratory of Development and Diseases,Institute of biotechnology,beijing 100070,china Department of Pulmonary Medicine Peking Union Medical College Hospital Chinese Academy of Medical Sciences Beijing China Department of Genetic Laboratory of Development and Diseases Institute of Biotechnology Beijing China

Aim:Myofibroblasts play important roles in the pathogenesis of lung *** growth factor（TGF）-β1has been widely recognized as a keyfibrogenic *** major signaling pathway of TGF--β1is through cytoplas-mic Smad *** study investigated the role of individual TGF--β1/Smadsignal proteins in mediating α-smooth muscle actin（α-SMA）gene expression,which is a well-known key marker of myofibroblast ***:Wetransiently cotransfected α-SMA promoter-luciferase fusion plasmid（p895-Luc）and Smad expression plasmids and measured Luc activity in TGF--β1-treated hu-man fetal lung *** induced Smad3 knockout mice lung fibrosis bybleomycin,α-SMA protein expression was assessed by Western ***-lagen protein was analyzed by measuring *** morphol-ogy was assessed by ***:We found that theoverexpression of Smad3,not Smad2 markedly increased TGF--β1-induced α-SMApromoter activity and α-SMA protein expression in vitro,whereas the over-expression of dominant negative mutant Smad3 and Smad7 repressed TGF--β1-induced α-SMA gene *** to wild-type mice,Smad3 knockoutmice showed attenuated lung fibrosis after bleomycin treatment,manifested bylower collagen production and myofibroblast ***:Ourstudy suggested TGF--β1/Smad3 is a major pathway which regulated themyofibroblast *** result indicates a potential significance forfuture attempts of attenuating the progression of human lung fibrosis by theinhibition of the Smad3 cascade.

关键词： myofibroblasts transforming growth factorβ1 Smad

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Cilia and ciliopathies:From Chlamydomonas and beyond

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Science china(Life Sciences) 2008年第6期51卷 479-486页

作者： PAN JunMin Department of Biological Sciences and biotechnology, Tsinghua University, beijing 100084, china Department of Biological Sciences and biotechnology Tsinghua University Beijing China

The biological function of motile cilia/flagella has long been recognized. The non-motile primary cilium, once regarded as a vestigial organelle, however, has been found recently to play unexpected roles in mammalian physiology and development. Defects in cilia have profound impact on human health. Diseases related to cilia, collectively called ciliopathies include male infertility, primary cilia dyskinesia, renal cyst formation, blindness, polydactyly, obesity, hypertension, and even mental retardation. Our current understanding of cilia and ciliopathies has been fueled by basic research employing various model organisms including Chlamydomonas, a unicellular green alga. This review article provides a general introduction to the cell biology of cilia and an overview of various cilia-related diseases.

关键词： Chlamydomonas cilia flagellla human disease ciliopathy

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Molecular architecture and engineering of spider dragline silk protein

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Progress in Natural Science:Materials International 2005年第9期15卷 769-776页

作者： ZHANG Hengmu and LIU Jinyuan(Department of Biological Sciences and biotechnology, Tsinghua University, beijing 100084, china) Department of Biological Sciences and biotechnology Tsinghua University Beijing 100084 China

Spider dragline silk, which is produced in spider major ampullate gland, is a composite proteinacious fiber with highly repetitive Ala-Gly-rich domain. The unique combination of both high tensile strength and high elasticity makes spider dragline silk superior to almost any other natural or synthetic fibers. Cloning of the genes reveals that the silk is composed of at least two major proteins. Each protein component contains multiple repeats of modular structures that alternate between Ala-rich domains and Gly-rich domains. Molecular engineering not only opens a door to the production of spidroins but also provides a valuable experimental system to test and further establish the relationship between modular structures and mechanical properties. Here, based on our own studies, we review the latest progress of the modular structure and genetic engineering and outline the future prospects.

关键词： spider dragline silk protein modular structure molecular engineering.

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Plant protein kinase genes induced by drought, high salt and cold stresses

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Chinese Science Bulletin 2000年第13期45卷 1153-1157页

作者： LIU Qiang , ZHANG Yong & Chen Shouyi1. Deparlmenl of Biological Science and biotechnology, Tsinghua University, beijing 100084, china 2. Department of Biological Science and biotechnology, Slate Key Laboratory of Biomembrane and Membrane biotechnology, Tsinghua University, beijing 100084, china 3. Institute of Genetics, Chinese Academy of Sciences, beijing 100101, china Department of Biological Science and biotechnology Tsinghua University Beijing China Department of Biological Science and biotechnology State Key Laboratory of Biomembrane and Membrane Biotechnology Tsinghua University Beijing China Institute of Genetics Chinese Academy of Sciences Beijing China

Drought, high salt and cold are three different kinds of environment stresses that severely influence the growth, development and productivity of crops. They all decrease the water state of plant cells, and consequently result in the harm of plant from water deficit. Several genes encoding protein kinases and induced by drought, high salt and low temperature have been isolated from Arabidopsis. These protein kinases include receptor protein kinase (RPK), MAP kinases, ribosomal-protein kinases and transcription-regulation protein kinase. The expression features of these genes and the regulatory roles of these protein kinases in stress response and signal transduction are discussed.

关键词： protein kinase environment stress signal transduction gene expression.

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