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Neuroglobin mutation associated with hypoxia adaptation in Tibet chicken

Progress in Natural science:Materials International 2007年第12期17卷 1419-1424页

作者： Zhang Lifan1, Liu Chong2. Lian Linsheng3, Zhao Chunjiang1, Bao Haigang1 and Wu Changxin1(1. college of Animal science and Technology,{2., beijing 100094, china 2. college of biological science,{2., beijing 100094, china 3. college of Animal science and Technology, Yunnan agricultural {12., Kunming 6502.1, china) college of Animal science and Technology China Agricultural University Beijing 100094 China college of biological {2. China Agricultural University Beijing 100094 China college of Animal science and Technology Yunnan Agricultural University Kunming 650201 China

Globin protein family plays an important role in storing and transporting oxygen. As a newly reported globin, the revealed function of neuroglobin includes binding and storing oxygen as well as facilitating the utilization of oxygen in neuronal cells. In the present study, mutations in exons of chicken Ngb gene were identified with the method of sequencing and created restriction site PCR in Tibet chicken and other four lowland chicken breeds. The mutations of Lys-2.2.(E4)-Asn and Ser-2.79(E4)-Gly were identified in exon 4 of the gene. The Lys-2.2.(E4)-Asn mutation existed only in Tibet chicken and the mutation frequencies increased with increasing altitude. Analysis of the haplotype and diplotype of the two mutations in Tibet chicken populations of different altitudes showed that the frequencies of TG haplotype and TTGG diplotype also increased with increasing altitude, while the reverse tendency was found on GGAA diplotype. Under the hypoxic simulation incubation, the main haplotype was TG in living embryos and GA in dead embryos. The results showed that the Lys-2.2.(E4)-Asn mutation may be a specific mutation associated with hypoxia adaptation in Tibet chicken.

关键词： Tibet chicken neuroglobin hypoxia adaptation Ngb gene mutation.

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Tn5-mutagenesis and identification of atr operon and trpE gene responsible for indole-3-acetic acid synthesis in Azospirillum brasilense Yu62

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Progress in Natural science:Materials International 2006年第4期16卷 366-372页

作者： XIE Baoen and CHEN Sanfeng State Key Laboratory for Agrobiotechnology, college of biological {2.s, china agricultural university, beijing 100094, china State Key Laboratory for Agrobiotechnology College of Biological Sciences China Agricultural University Beijing 100094 China

To bring more information about synthesis of indole-3-acetic acid (IAA) from Azospirillum brasilense, a Tn5-insertion library of A. brasilense Yu62.was constructed and subjected to screening for IAA producing mutants. Two mutants with decreased IAA levels, named as A3 and A2., were isolated. The sequence analysis of loci tagged showed that the Tn5-1063a was located in the atrA gene encoding GntR family transcriptional regulator and trpE gene encoding component I of anthranilate synthase respectively. At the same time. atrB encoding phosphotransferase and atrC encoding aminotransferase were cloned downstream the atrA gene and atrA, atrB and atrC were clustered in an operon. Mutagenesis and complementation studies showed that atrA and atrC were involved in IAA synthesis. IAA levels of trpE mutant and wild-type strain could be improved by adding anthranilate into the medium.

关键词： indole-3-acetic acid (IAA) IAA mutants Azospirillum brasilense atrABC cluster trpE Tn5 transposon.

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Purification of a Novel Antibacterial Short Peptide in Earthworm Eisenia foetida

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Acta Biochimica et Biophysica Sinica 2004年第4期36卷 297-302页

作者： Yan-Qin LIU1,2. Zhen-Jun SUN1*, Chong WANG1, Shi-Jie LI2. and Yu-Zhi LIU2.college of Resource and Environment science,{2., beijing 100094, china 2.0} of Animal science, Hebei agricultural university, Baoding 071001, china college of Resource and Environment science China Agricultural UniversityBeijing 100094 China college of Animal science Hebei Agricultural UniversityBaoding 071001 China

A novel antimicrobial short peptide was purified from earthworm (Eisenia foetida) by a five-step protocol including ammonium sulfate precipitation, ultrafiltration, DE-52.ion exchange chromatography, Sephadex G-10 column chromatography, and C-18 reversed-phase HPLC techniques. The purified peptide was applied to the MALDI-TOF MS to determine the molecular mass and was also subjected to TOF MS-MS analysis to determine the amino acid sequence. As a result, a novel antibacterial peptide, named OEP312., was obtained, with the molecular mass of 510.8 Da and the sequence being “ACSAG”.

关键词： antibacterial peptide earthworm purification

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A five-fold pig bacterial artificial chromosome library:a resource for positional cloning and physical mapping

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Progress in Natural science:Materials International 2006年第08期16卷 889-892页

作者： LIU Wei, ZHANG Ying, LIU Zhaoliang, GUO Li, WANG Xiaobo, FEI Jing, FENG Jidong, ZHAO Rui, HU Xiaoxiang and LI Ning (The State Key Laboratory for Agro-Biotechnology, college of Biology, china agricultural university,{2., china college of Animal science and Technology, china agricultural university,{2., china) [a]The State Key Laboratory for Agno-Biotechnology College of Biology China Agricultural University Beijing China [b]college of Animal science and Technology China Agricultural University Beijing China

A pig BAC library was constructed with genomic DNA from a male Erhualian pig. After partial digestion with HindⅢor BamHⅠthe fragments obtained were cloned into the pBeloBAC11 vector. The library consists of 18432. clones which stored in 480 pieces 384-well plates (2. plates per superpool). A two-step 4-dimension PCR screening system was established to screen the positive clones. An average insert size of 12. kb was estimated from 105 randomly isolated clones, which indicates that the library is more than five times of genomic coverage. For the demonstration of the probability to pick out any unique genes or DNA markers from the library, 10 single-copy genes were screened out and the positive clones were yielded between 1 and 8 with an average of 3.6. Positive superpools were obtained for 32.microsatellite markers selected from different regions of pig genome. The number of positive superpools for each marker varies from 1 to 9 with an average of 4.78. This BAC library provides an additional resource for pig physical mapping and gene identifica-

关键词： pig BAC library PCR screening system.

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Enhancement of monacolin K production via intergeneric protoplast fusion between Aspergillus terreus and Monascus anka

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Progress in Natural science:Materials International 2007年第6期17卷 703-707页

作者： Chen Zhi, Lin Wen, Yu Ping and Song Yuan(Department of Microbiology, college of biological {2.s, china agricultural university, beijing 100094, china) Department of Microbiology College of Biological Sciences China Agricultural University Beijing 100094 China

Intergenric protoplast fusion between Aspergillus terreus CA99 and Monascus anka M-3, the high and low producers of monacolin K respectively,was performed for enhancement of monacolin K production. The 2.-hour-old mycelia of A. terreus CA99 and M. anka M-3 were treated with 0.5% lywallzyme, 0.3% snailase and 0.3% cellulase at 34℃ for 5 h and at 30℃ for 3.5 h, and their protoplasts formation reached 1.76×107/mL and 1.68×107/mL respectively. Parental protoplasts were irradiated with a 30 W UV light away from 30 cm for 3 min and then mixed. The mixture was incubated with 30% PEG 6000 for 15 min. The reviving fusants were isolated on the regeneration plates. Of the 363 fusants isolated, over 100 showed enhanced monacolin K production compared with the parental strain M. anka M-3. Ten of them produced monacolin K about 1.6-fold of that *** M-3 does and the monacolin K titer of two fusants (F49 and F104) increased by about 1-fold. The monacolin K yields of F49 and F104 were 460 μg/mL and 457 μg/mL respectively. In optimized fermentation medium, the monacolin K titer of F49 reached 12.6 μg/mL.

关键词： monacolin K Monascus anka Aspergillus terreus protoplast fusion fermentation.

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Types of voltage-dependent calcium channels involved in high potassium depolarization-induced amylase secretion in the exocrine pancreatic tumour cell line AR4-2.

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Cell Research 1998年第1期8卷 23-31页

作者： CUI ZONG JIE (beijing agricultural {2. Faculty of biological sciences beijing 100094, china) beijing agricultural {2. Faculty of biological sciences Beijing 100094 China

In the perifused fura-2.loaded exocrine pancreatic acinar cell line AR4-2. pulses of high potassium induced repetitive increases in intracellular calcium. Attached cells when stimulated with high potassium secreted large amount of amylase. High potassium-induced secretion was dependent both on the concentration of potassium and duration of stimulation. High potassium induced increases in intracellular calcium were inhibited by voltage-dependent calcium channel antagonists with an order of potency as follows: nifedipine > ω-agatoxin IVA > ω-conotoxin GVIA. In contrast, the L-type calcium channel antagonist nifedipine almost completely inhibited potassium-induced amylase secretion, whereas the N-type channel antagonist ω-conotoxin GVIA was without effect. The P-type channel antagonist ω-agatoxin IVA had a small inhibitory effect, but this inhibition was not significant at the level of amylase secretion. In conclusion, the AR4-2. cell line possesses different voltage-dependent calcium channels (L, P,N) with the L-type predominantly involved in depolarization induced amylase secretion.

关键词： AR4-2. pancreatic acinar cells amylase secretion calcium channels

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Pattern phenomena in an rf discharge dusty plasma system

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science china(Physics,Mechanics & Astronomy) 2006年第5期49卷 588-596页

作者： HUANG Feng1,2. YE Maofu2.& WANG Long2.1. college of science,{2., beijing 100083, china 2. Institute of Physics, Chinese Academy of sciences, beijing 100080, china 1. college of science China Agricultural University Beijing 100083 China 2. Institute of Physics Chinese Academy of Sciences Beijing 100080 China

Various dust patterns are observed in an rf discharge dusty plasma system. According to the dust growth process from small to large in size, the formation of different dust patterns can be divided into two stages: the small-particle stage (or dust cloud stage), and the large-particle stage (or dust crystal stage). The evolution relations between different dust patterns with gas pressure changing are investigated. Dust voids, dust acoustic waves and strong turbulence modes are presented at the small-particle stage. The self-organized dust lattices and dust clusters are investigated at the large-particle stage. The static structure of a dust lattice is characterized by means of the pair correlation function. Dust clusters formed by particles with different numbers and the regular evolution of the clusters with gas pressure are also investigated. The packing sequences of dust clusters are verified through two-dimensional confined molecular dynamics simulations.

关键词： dusty plasma dust patterns

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Production of porcine cloned transgenic embryos expressing green fluorescent protein by somatic cell nuclear transfer

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science china(Life sciences) 2006年第2期49卷 164-171页

作者： ZHANG Yunhai1, PAN Dengke1,2. SUN Xiuzhu1, SUN Guojie1, WANG Xiaobo1, LIU Xiaohui1, LI Yan1, DAI Yunping1 & LI Ning1 1. State Key Laboratory for Agrobiotechnology, china agricultural university, beijing 100094,{2. 2. college of Animal science and Technology, china agricultural university, beijing 100094,{2. State Key Laboratory for Agrobiotechnology China Agricultural University Beijing 100094 China college of Animal science Technology China Agricultural University Beijing 100094 China

In the present study, nuclear transferred embryos (NTEs) were reconstructed by using pig fetal fibroblasts as donors; in vitro matured oocytes as recipients. The effects of G418 selection on donor cells, duration of IVM of prepubertal gilt oocytes; oxygen tension in IVM of oocytes were investigated. The results were as follows: (i) When G418 selected cells expressing GFP were used as donors, the cleavage rate of NTEs decreased drastically in comparison to NTEs derived from donors without antibiotic selection (47.5% vs. 71.6%, p>0.05). For the blastocyst rate, no significant difference was observed between two groups (10% vs. 10.4%, p2.h (83.6% vs. 96.7%, p>0.05). However, no statistical difference was observed between NTEs derived from oocytes of 36 h IVM group; NTEs from oocytes of 42.h IVM group in the rates of cleavage (59.3% vs. 73.6%, p2., p2. tension; NTEs derived from oocytes matured under higher oxygen tension (2.% O2. in cleavage rate (70.6% vs. 67.1%, p2.3%, p2.h, while no significant differences were observed for developmental potential of transgenic embryos. Thus IVM 42.h is the better choice in order to obtain maximum number of MII oocytes as recipients. (iii) Lower oxygen tension; higher oxygen tension in IVM have no significant effect on development of cloned embryos.

关键词： transgenic cloning, GFP, Pig, early development.

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Aberrant histone H4 acetylation in dead somatic cell-cloned calves

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Progress in Natural science:Materials International 2008年第7期18卷 813-818页

作者： Lei Zhang a,b,*, Shaohua Wang a, Qiang Li a, Xiangdong Ding c, Yunping Dai a, Ning Li a,* a State Key Laboratory for Agrobiotechnology, china agricultural university, beijing 100094,{2. b beijing Gene & Protein Biotechnology Co. LTD, beijing 100094,{2. c college of Animal science and Technology, china agricultural university, beijing 100094,{2. State Key Laboratory for Agrobiotechnology China Agricultural University Beijing 100094 China beijing Gene & Protein Biotechnology Co. LTD Beijing 100094 China college of Animal science and Technology China Agricultural University Beijing 100094 China

In somatic cell-cloned animals, inefficient epigenetic reprogramming can result in an inappropriate gene expression and histone H4 acetylation is one of the key epigenetic modifications regulating gene expression. In this study, we investigated the levels of histone H4 acetylation of 11 development-related genes and expression levels of 19 genes in lungs of three normal control calves and nine aber- rant somatic cell-cloned calves. The results showed that nine studied genes had decreased acetylation levels in aberrant clones (p 0.05). Whereas 13 genes had significantly decreased expression (p 0.05), and only one gene had higher expression level in clones (p < 0.05). Furthermore, FGFR, GHR, HGFR and IGF1 genes showed lowered levels of both histone H4 acetylation and expression in aberrant clones than in controls, and the level of histone H4 acetylation was even more lowered in aberrant clones than those in controls. It was suggested that the lower levels of histone H4 acetylation in aberrant clones caused by the previous memory of cell differentiation might not support enough chromatin reprogramming, thus affecting appropriate gene expressions, and growth and development of the cloned calves. To our knowledge, this is the first study on how histone H4 acetylation affects gene expression in organs of somatic cell-cloned calves.

关键词： Somatic cell-cloned calves Histone H4 acetylation Gene expression Lungs

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The refined theory of deep rectangular beams based on general solutions of elasticity

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science china(Physics,Mechanics & Astronomy) 2006年第3期49卷 291-303页

作者： GAO Yang1 & WANG Minzhong2.1. college of science,{2., beijing 100083, china 2. State Key Laboratory for Turbulence and Complex Systems and Department of Mechanics and Engi- neering science, Peking university, beijing 100871, china college of science China Agricultural University Beijing 100083 China State Key Laboratory for Turbulence Complex Systems Department of Mechanics Engineering science Peking University Beijing 100871 China

The problem of deducing one-dimensional theory from two-dimensional the- ory for a homogeneous isotropic beam is investigated. Based on elasticity theory, the re- fined theory of rectangular beams is derived by using Papkovich-Neuber solution and Lur’e method without ad hoc assumptions. It is shown that the displacements and stresses of the beam can be represented by the angle of rotation and the deflection of the neutral surface. Based on the refined beam theory, the exact equations for the beam without transverse surface loadings are derived and consist of two governing differential equations: the fourth-order equation and the transcendental equation. The approximate equations for the beam under transverse loadings are derived directly from the refined beam theory and are almost the same as the governing equations of Timoshenko beam theory. In two ex- amples, it is shown that the new theory provides better results than Levinson’s beam the- ory when compared with those obtained from the linear theory of elasticity.

关键词： deep rectangular beams,the refined theory,Papkovich-Neuber solution,Lur'e method,governing equation

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