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酵母内含子在基因序列中的分布对基因转录效率的影响

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生物化学与生物物理进展 2003年第6期30卷 945-949页

作者：张静石秀凡杨恒芬云南大学应用统计中心中国科学院昆明动物研究所

对酵母中高效转录和低效转录基因内含子序列寡核苷酸使用情况的对照分析 ,显示两类内含子的序列结构有差异 ,并且高效转录基因内含子序列含有较多潜在的转录因子结合位点 ,由此推测内含子可能参与基因转录的调控 .这个结论有待更多的数... 详细信息

对酵母中高效转录和低效转录基因内含子序列寡核苷酸使用情况的对照分析 ,显示两类内含子的序列结构有差异 ,并且高效转录基因内含子序列含有较多潜在的转录因子结合位点 ,由此推测内含子可能参与基因转录的调控 .这个结论有待更多的数据证实 .对内含子和外显子在两组基因序列中的分布 (长度、位置等 )进行详细比较分析后显示 ,高效转录基因内含子和低效转录基因内含子的长度有比较明显的界限 .两组基因中外显子长度的均值虽然有些差异 ,却没有明显的界限 .基因序列长度与外显子长度的情况相似 .虽然内含子的相对位置在两类基因中都很靠近 5′端 ,但是从实际位置看 ,高效转录基因中比较多的内含子很靠近基因的 5′端 ,有些则位于 5′ UTR区域 .这些结果提示 ,基因的转录效率与内含子的长度有关 ,与外显子及基因序列的长度无关 ,内含子的位置也可能影响转录效率 ,内含子对基因转录的调控可能与基因上游的转录调控有关联。

关键词：酵母基因转录频率内含子长度内含子位置基因序列基因转录

TRANSIENT EFFECT OF A BOGER FLUID FLOWING AROUND A CONFINED CYLINDER

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chinese Journal of Polymer Science 2001年第4期19卷 377-384页

作者： Xian-feng Li Huai-tian Bu De-lu Zhao State key laboratory of Polymer Physics and Chemistry Center for molecular Science,{3. of Chemistry, chinese academy of sciences, Beijing 100080, China 中科院化学所高分子物理与化学国家重点实验室北京

This paper is concerned with the numerical simulation of the transient effect of an inertialess Boger flow past a confined circular cylinder and the comparison of predictions with particle image velocimetry (PIV) measurements given by Shiang et al.. Dynamic simulation based on the Oldroyd-B constitutive model was carried out using a Lagrangian-Eulerian algorithm. The evolution of velocity field was obtained for the flow at two Deborah (De) numbers, i.e. De = 1.2 and 3.0. At low De, the flow reached steady state rapidly, and showed a symmetric flow regime. However, at high De, the time required to reach steady flow behind the cylinder increased significantly, and the distribution of the velocity field appears to be asymmetric with respect to the stagnation line. Fairly good agreement between the numerical results and the experimental observations is reported. It can be concluded that both the experimental measurements and the present simulations indicate that the elasticity of the polymeric flow strongly affect the flow regime of viscoelastic flow around a confined cylinder.

关键词： transient effect flow around a cylinder Lagrangian-Eulerian algorithm Oldroyd-B model

The Australasian frog family Ceratobatrachidae in China,Myanmar and Thailand:discovery of a new Himalayan forest frog clade

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Zoological Research 2016年第1期37卷 7-14页

作者： Fang YAN Ke JIANG Kai WANG Jie-Qiong JIN Chatmongkon SUWANNAPOOM Cheng LI Jens V.VINDUM Rafe M.BROWN Jing CHE State key laboratory of Genetic Resources and evolution,{3. institute of zoology,chinese academy of sciences Southeast Asia Biodiversity Research institute,chinese academy of sciences Sam Noble Oklahoma Museum of Natural History and Department of Biology,University of Oklahoma School of Agriculture and Natural Resources,University of Phayao Imaging Biodiversity Expedition Department of Herpetology,California academy of sciences Biodiversity institute and Department of Ecology and evolutionary Biology,13.5 Jayhawk Blvd,University of Kansas State key laboratory of Genetic Resources and evolution Kunming Institute of Zoology Chinese Academy of Sciences Kunming Yunnan 650223 ChinaSoutheast Asia Biodiversity Research Institute Chinese Academy of Sciences Yezin Nay Pyi Taw 05282 Myanmar. State key laboratory of Genetic Resources and evolution Kunming Institute of Zoology Chinese Academy of Sciences Kunming Yunnan 650223 China Sam Noble Oklahoma Museum of Natural History and Department of Biology University of Oklahoma Norman OK 73072-7029 U.S.A. State key laboratory of Genetic Resources and evolution Kunming Institute of Zoology Chinese Academy of Sciences Kunming Yunnan 650223 China. State key laboratory of Genetic Resources and evolution Kunming Institute of Zoology Chinese Academy of Sciences Kunming Yunnan 650223 China School of Agriculture and Natural Resources University of Phayao Phayao 56000 Thailand. Imaging Biodiversity Expedition Beijing 100107 China. Department of Herpetology California Academy of Sciences California 94118 U.S.A. Biodiversity institute and Department of Ecology and evolutionary Biology 1345 Jayhawk Blvd University of Kansas Lawrence KS 66045 U.S.A. State key laboratory of Genetic Resources and evolution Kunming Institute of Zoology Chinese Academy of Sciences Kunming Yunnan 650223 China. chej@***.

In an effort to study the systematic affinities and species- level phylogenetic relationships of the enigmatic anurans vadably assigned to the genera Ingerana or Limnonectes （family Dicroglossidae）, we collected new molecular sequence data for five species including four Himalayan taxa, Limnonectes xizangensis, Lim. medogensis, Lim. alpine, Ingerana borealis and one southeast Asian species, I. tasanae, and analyzed these together with data from previous studies involving other ostensibly related taxa. Our surprising results demonstrate unequivocally that Lim. xizangensis, Lim. medogensis and Lira. alpine form a strongly supported clade, the sister-group of the family Australasian forest frog family Ceratobatrachidae. This discovery requires an expansion of the definition of Ceratobatrachidae and represents the first record of this family in China. These three species are distinguished from the species of Ingerana and Limnonectes by the：（1） absence of interdigital webbing of the foot, （2） absence of terminal discs on fingers and toes, （3. absence of circumarginal grooves on the fingers and toes, and （4） absence of tarsal folds. Given their phylogenetic and morphological distinctiveness, we assign them to the oldest available generic name for this clade, Liurana Dubois 1987, and transfer Liurana from Dicroglossidae to the family Ceratobatrachidae. In contrast, Ingerana tasanae was found to be clustered with strong support with the recently described genus Alcalus （Ceratobatrachidae）, a small clade of otherwise Sundaic species; this constitutes a new record of the family Ceratobatrachidae for Myanmar and Thailand. Finally, Ingerana borealis clustered with the ＂true＂ Ingerana （family Dicroglossidae）, for which the type species is L tenasserimensis.

关键词： Dicroglossidae Himalaya Liurana

Pain research in China

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Science China(Life sciences) 2010年第3期53卷 356-362页

作者： ZHANG Xu institute of Neuroscience,State key laboratory of Neuroscience,Shanghai institutes for Biological sciences,chinese academy of sciences,Shanghai 20003.,China institute of Neuroscience State Key Laboratory of Neuroscience Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai China

In addition to investigating the anatomy,neurochemistry and neurophysiology of pain pathways,chinese researchers have extended their work into the molecular and cellular mechanisms of sensory afferent transmission at the spinal cord level as well as cognitive processing in the *** mechanism underlying acupuncture analgesia remains a subject of special interest for chinese pain researchers,with the aim of combining clinical practice with the understanding of pain transmission and analgesic mechanism.

关键词： dorsal root ganglion spinal cord nociception receptors ion channels gene expression

VISCOELASTIC BEHAVIOR OF THE NON-HOOKE DEFORMATION BEFORE YIELDING IN UNIAXIAL DRAWING OF AMORPHOUS POLY(ETHYLENE TEREPHTHALATE)

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chinese Journal of Polymer Science 2001年第4期19卷 399-405页

作者： Zhen-hua Yuan De-yan Shen Ren-yuan Qian Polymer Physics laboratory Center for molecular Science, institute of Chemistry{3., Beijing 100080 China 中科院化学所高分子物理及化学国家重点实验室北京

Viscoelastic behavior of the non-Hooke deformation of amorphous PET film before yield was investigated in the temperature region 74-80.5 degreesC around the glass transition temperature. The film specimen was drawn to yield point followed by unloading to zero stress, then the residual deformation was held constant; while the subsequent evolution of the stress was recorded. An induction period was found in the course of stress evolution followed by a stress step-increase. The induction period decreases with increasing drawing temperature with an activation energy of 1.10 MJ/mol.K, which is attributed to the time needed for the relaxation of rubbery deformation through cooperative internal rotations. At temperatures lower than 74 degreesC, there is no stress increase or the induction period becomes too long to be observed. Thus the nature of anelasticity in the non-Hooke region before yielding is attributed to stress induced rubbery deformation. The experimental results are interpreted in terms of Perez' theological model of a series connected Hooks spring and a Voigt element consisting of a parallel connected elastic spring and a dashpot.

关键词： pre-yield deformation PET uniaxial drawing non-Hooke deformation viscoelasticity stress induced rubbery deformation

molecular identification of species in Prunus sect. Persica (Rosaceae), with emphasis on evaluation of candidate barcodes for plants

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Journal of Systematics and evolution 2011年第2期49卷 138-145页

作者： 1,2 Xu QUAN 1 Shi-Liang ZHOU 1 (State key laboratory of Systematic and evolutionary Botany, {3. of Botany, chinese academy of sciences, Beijing 100093. China) 2 (Graduate School of the chinese academy of sciences, Beijing 100049, China) (State key laboratory of Systematic and evolutionary Botany Institute of Botany Chinese Academy of Sciences Beijing 100093 China) (Graduate School of the chinese academy of sciences Beijing 100049 China)

Species of Prunus L. sect. Persica are not only important fruit trees, but also popular ornamental and medicinal plants. Correct identification of seedlings, barks, or fruit kernels is sometimes required, but no reliable morphological characters are available. Nowadays, the technique of DNA barcoding has the potential to meet such requirements. In this study, we evaluated the suitability of 11 DNA loci (atpB-rbcL, trnH-psbA, trnL-F, trnS-G, atpF-H, rbcL, matK, rpoB, rpoC1, nad1, and internal transcribed spacer [ITS]) as candidate DNA barcodes for peaches, using samples from 3. populations, covering all the species in sect. Persica. On the whole, the primers worked well in this group and sequencing difficulties were met only in the case of ITS locus. Five loci (rbcL, matK, rpoB, rpoC, and nad1) have very low variation rates, whereas atpB-rbcL, atpF-H, trnH-psbA, trnL-F and trnS-G show more variability. The most variable loci, atpB-rbcL and trnH-psbA, can distinguish three of the five species. Two two-locus combinations, atpB-rbcL+trnL-F and atpB-rbcL+atpF-H, can resolve all five species. We also find that identification powers of the loci are method-dependent. The NeighborNet method shows higher species identification power than maximum parsimony, neighbor joining, and unweighted pair group method with arithmetic mean methods.

关键词： atpB-rbcL DNA barcode Prunus sect. Persica trnL-F.

Evaluation of 10 plant barcodes in Bryophyta (Mosses)

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Journal of Systematics and evolution 2010年第1期48卷 36-46页

作者： 1,2 Yan LIU 3.Hai-Fei YAN 4 Tong CAO 3.Xue-Jun GE 1(institute of Applied Ecology, chinese academy of sciences, Shenyang 110016, China) 2(Graduate University of the chinese academy of sciences, Beijing 100049, China) 3.{3. laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, chinese academy of sciences, Guangzhou 510650, China) 4(College of Life & Environment sciences, Shanghai Normal University, Shanghai 20023., China) (institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China) (Graduate University of the chinese academy of sciences Beijing 100049 China) (key laboratory of Plant Resources Conservation and Sustainable Utilization South China Botanical Garden Chinese Academy of Sciences Guangzhou 510650 China) (College of Life & Environment sciences Shanghai Normal University Shanghai 200234 China)

DNA barcoding is a molecular tool that uses a standardized DNA region to identify *** preliminary study reported here is the first attempt to specifically focus on universality and attributes of candidate barcodes across a wide systematic range of *** tested eight previously proposed plant barcoding regions(atpF-atpH, ITS2, matK, psbK-psbI, rbcL, rpoB, rpoC1, and trnH-psbA) and two popular phylogenetic markers(rps4 and trnL-trnF of cpDNA) in 49 moss species and 9 liverwort species, representing half of the orders in moss *** ITS2, rbcL, rpoC1, rps4, trnH-psbA and trnL-trnF regions showed good universality, and therefore the efficacy of these loci as DNA barcodes was further evaluated in 3. mosses and 2 liverworts, each of which included two to three individuals per *** five loci, ***, rpoC1, rps4, trnH-psbA and trnL-trnF, were easy to amplify and sequence and showed significant inter-specific genetic variability, making them potentially useful DNA barcodes for *** best performing single loci were the rbcL and rpoC1 coding *** loci showed equivalent performance and combinations of them did not greatly increase their discrimination *** addition, phylogenies generated from each of the separate regions and multi-locus combinations by using best-fit and Kimura 2-parameter models were compared, but no significant difference was found.

关键词： Bryophyta DNA barcoding rbcL rpoC1 rps4 trnH-psbA trnL-trnF.

The long-standing unresolved Ursidae (bear family) phytogeny revisited: exploring deeper with complete mitochondria genomes (mitogenomics)

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The long-standing unresolved Ursidae (bear family) phytogeny...

Nerve Growth Factor Prevents the Apoptosis-associated Increase in Acetylcholinesterase Activity after Hydrogen Peroxide Treatment by Activating Akt

中国遗传学会功能基因组学研讨会

作者： Li Yu, Yi-Wei Li, Ya-ping Zhang laboratory for Conservation and Utilization of Bio-resource, Yunnan University, kunming 650091 laboratory of {3. Biology of Domestic Animals, and cellular and {3. evolution, kunming institute of zoology, kunming 650223.

The taxomic classification and phylogenetic relationships within the bear family remain argumentative subjects in recent years. Prior investigation has been concentra ted on the application of individual or part mitochondrial(mt) gene, herein we employ complete mt genome information to clarify these enigmatic problems. The combined analyses of 12 protein-coding mt genes not only corroborated prior hypotheses, positioning the spectacled bear most basally and

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Acta Biochimica et Biophysica Sinica 2007年第1期39卷 46-56页

作者： Hua JIANG~(1,3. Jingya ZHANG~(1,3. Hui ZHU~(1,3. Hong LI~2 and Xuejun ZHANG~1 ~1laboratory of molecular Cell Biology,institute of Biochemistry and Cell Biology,Shangha institutes for Biological sciences,chinese academy of sciences,Shanghai 20003.,China ~2DEFEMA,Faculté de Medecine et de Pharmacie,University of Rouen,Rouen 76821,France ~3.raduate school of the chinese academy of sciences,Beijing 100080,China laboratory of molecular Cell Biology Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of SciencesShanghai 200031 China Graduate school of the chinese academy of sciences Beijing 100080 China DEFEMA Faculté de Medecine et de Pharmacie University of RouenRouen 76821 France

Acetylcholinesterase （ACHE） is thought to play an important role during *** resultsshowed that H2O2induced AChE activity,a functional marker in apoptosis,increases in neuronal-like PC ***, which is involved in cellular redox homeostasis,inhibited the increase of AChE activity,suggesting that reactive oxygen species （ROS） play a key role in this *** investigation showedthat the elevation of AChE was observed after the degradation of Akt, release of cytochrome c from mitochondriainto the cytosol,and activation of caspase family *** nerve growth factor （NGF） was present,with the maintenance of Akt level,the elevation of AChE,the cytochrome c diffusion,as well as apoptosiswere markedly attenuated in H202-treated PC 12 cells. However,wortmannin,an inhibitor of the PI3./Aktpathway,accelerated the apoptosis and increased the AChE *** overexpression of constitutivelyactivated Akt,which is a downstream signalling element of the NGF receptor TrkA,delayed mitochondrialcollapse and inhibited elevation of AChE ***, NGF prevented apoptosis and elevation of AChEactivity by activating the Akt pathway and stabilizing the function of mitochondria.

关键词： acetylcholinesterase(AChE) reactive oxygen species(ROS) Akt apoptosis