Overexpression of γ-aminobutyric acid transporter subtype I leads to susceptibility to Kainic acid-induced seizure in transgenic mice

INTroDUCTION.7-aminobutyric acid (GABA), a major in-hibitory neurotransmitter in vertebrate brain, in--duces neuronal inhibition via GABA receptors. Adeficiency of GABAergic inhibition has been hy-pothesized to be a principal factor in the patho-genesis of epilepsy[1]. GABA transporters are im-portant components of the GABAergic system, andfunction in part to terminate the GABA transmis-sion through rapid re-uptake of GABA into thepresynaptic neurons and surrounding gliaJ cells[2…     

利用SSR标记分析海南普通野生稻的遗传多样性

选用平均分布于水稻基因组的28对SSR引物,对海南不同纬度5个普通野生稻居群的163份材料进行遗传多样性和遗传结构研究。结果表明:(1)海南普通野生稻具有较高的遗传多样性,28个位点共检测到227个等位变异,平均等位变异数A=8.1071,有效等位变异数Ae=4.4190,平均期望杂合度He=0.4004,实际观察杂合度Ho=0.7062,香农指数I=1.6048;(2)居群的遗传分化系数较大,总的遗传变异中有46.40%存在于居群间(Fst=0.4640);(3)居群内杂合体较高(F is=-0.7069),根据固定指数(F=0.0588)计算出的异交率t=0.8889,说明海南普通野生稻的繁育系统属于一种较高的异交混合交配类型。     

香薷叶表皮腺毛及其分泌黄酮类物质的组织化学研究

利用光学显微技术和扫描电镜技术,研究了香薷营养生长期和生殖生长期的枝条上部、中部、下部叶片的腺毛种类、分布及数量;采用组织化学染色和荧光显微技术,观察香薷腺毛分泌黄酮类物质的过程,探讨香薷叶表皮腺毛的泌香机理,为生产中确定提取香薷黄酮类物质的最佳取材时期提供依据。结果表明:(1)香薷叶表皮有头状腺毛和盾状腺毛,成熟的头状腺毛包括基细胞、柄细胞和头部,头部较小,呈半圆球型,直径为(20±2)μm;发育近成熟的盾状腺毛头部较大,呈盾状,直径为(60±5)μm。(2)香薷叶片远轴面和近轴面均有腺毛的分布,远轴面分布较多,近轴面分布较少;盾状腺毛主要分布在叶的远轴面,头状腺毛在叶的两面均有分布;腺毛密度随节位的降低而减少,节位相同时,营养生长期叶片上的腺毛密度(283.9个/mm2)高于生殖生长期(194.4个/mm2)。(3)香薷头状腺毛和盾状腺毛均能分泌黄酮类物质,且随着腺毛的发育成熟,黄酮类物质逐渐积累于腺毛的头部。     

基于cpDNA和rDNA ITS片段分析西南地区青杨派杨树的系统发育与进化关系

西南地区青杨派杨树种质资源丰富,可为杨树遗传改良提供珍贵的基因资源,但树种之间形态学差异细微,该研究以山杨作为外类群,测定了西南地区及其他地区杨属青杨派17个种(杂种)共36份样本的3个叶绿体片段(atpF-atpH、trnL-F和matK)和核糖体ITS片段,并对其进行系统发育分析,以探讨西南地区青杨派树种的系统进化关系。结果表明:(1)在所有样本中,3个叶绿体片段atpF-atpH、trnL-F、matK的长度分别为605~634bp、957~1 010bp、819bp,3个片段拼接后的联合序列包含29个变异位点和15个信息位点;ITS片段对齐后的长度为646bp,变异位点19个,信息位点17个。(2)基于叶绿体联合序列和ITS片段的杨属青杨派树种的平均遗传距离分别为0.001 3和0.003 6。叶绿体联合片段的MP和Bayes系统树树型基本一致,青杨派树种可以划分为2组,第1组由青杨、三脉青杨、大青杨和辽杨构成;第2组中的小叶杨、小青杨、川杨、德钦杨、昌都杨、乡城杨、康定杨、西南杨、滇杨和藏川杨不能有效区分,且均与缘毛杨的遗传关系较近。(3)基于ITS的系统树与叶绿体联合片段构建的系统树差异不大,仅在于第2组中的小青杨与小叶杨、川杨等差异明显,与第1组中的树种紧密聚拢。     

Genetic Differentiation of Quercus mongolica and Q. liaotungensis Based on Morphological Observation,Isozyme and DNA Analysis

The Liaodong oak ( Quercus liaotungensis Koidz. ) is a close relative of the Mongolia oak ( Q. mongolica Fisch. ) which were separated by some morphological characters, such as the number of leaf lobes and the squamate form of cupula. Recently some authors observed that morphological diversity made the Liaodong oak unable to separate clearly from the Mongolia one, therefore, plant materials have been collected from Maoer Mountain of Heilongjiang province as a typical Q. mongolica population, and from Guandi Mountain of Shanxi Province which represented the typical Liaodong oak population to compare isozyme and DNA diversity between both species. The winter bud samples were also analysed from Dongling Mountain near Beijing City since Dongling population is an intermediate form between the Maoer population and the Guandi population morphologically. Statistics of 13 putative loci belonging to 5 enzymes showed a high level of diversity within all populations. The value of genetic distance among populations was low, and showed that the Dongling population genetically located at the middle of both typical species. DNA data also showed that both typical oak populations shared similar variation with the Dongling population. Among 172 polymorphic RAPD and DAF loci, no population-specific band has been found. A significant difference in frequency of amplified products existed in 26 loci. Except for 3 irregular ones, frequency distribution of 23 loci seems clinal. The Dongling population also genetically located at the middle of both flanking populations. It was worth to note that the OPD-08434 was probably unique to the Dongling oak since its frequency in the Guandi population has been estimated up to 100% and decreased to 0 in the Maeer population. The Dongling population received this unique DNA from the Guandi population probably by introgression. The strong gene flow in both directions implied a long history of distributive continuity for both oak species. High levels of morphological, isozymatic and DNA diversity supplied enough genetic basis for reconstruction of degraded oak ecosystems.     

Finding spatial regularity in mosaic landscapes: two methods integrated

Two methods were employed to find spatial regularity in a complicated mountain landscape of Beijing, China on the basis of functional and structural affinities. The first approach applied Affinity Analysis based on species composition to landscape. The mosaic diversity of the landscape was 3.5298>3, which means the study landscape is complex and controlled by multiple environmental gradients. These landscape types were divided into 3 parts according to the mean affinity values of 0.2143 and 0.7857 (0.5±1 SD). Modal sites are the central types of the landscape, which include a zonal broad-leaved forest of the region and a conifer plantation replacing the former. Outliers are found in the highest altitude and the lowest, both have few species in common with the above two modal types. The remaining landscape types are intermediate sites, which are transitional between modals and outliers, broadly distributed throughout mountain environments. Neighbor types have more species in common than those more widely separated, which probably distributed adjacently in space or in similar quality habitat. The other method employed is the new TWINSPAN analysis by substituting spatial neighboring data of landscape types for species composition data. It clearly divided the landscape types into three groups, i.e., subalpine, middle and low mountain groups, which were correlated with altitude, as well as influenced by human disturbance. The new TWINSPAN classification method is more reliable in finding spatial gradient of patchy landscapes than affinity analysis; however, affinity analysis is useful in finding species diversity pattern and the importance of landscape types in a region. Integrating advantages of the two methods could supply complete and reliable information on how landscape types are distributed in space, which environmental gradient dominates the spatial distribution of the landscape types, as well as where important and unusual types are located.     

组蛋白乙酰基转移酶1在肝癌细胞中介导的蛋白质乙酰化修饰谱分析

赖氨酸乙酰化是重要的蛋白质翻译后修饰之一,广泛存在于细胞的生理和病理过程.组蛋白乙酰基转移酶1(HAT1)作为第一个被鉴定的蛋白ε-氨基赖氨酸乙酰基转移酶,具有介导组蛋白和非组蛋白乙酰化的作用.然而,在肝癌细胞中HAT1介导的乙酰化蛋白质及其修饰位点目前仍不清楚.本研究首先揭示了 HAT1在肝癌组织中呈高表达,并且与预...     

飞蝗雌成虫脂肪体G蛋白偶联受体鉴定及其在卵发育中的功能

【目的】本研究旨在鉴定飞蝗Locusta migratoria雌成虫脂肪体中表达的G蛋白偶联受体(G protein-coupled receptor, GPCR)基因,揭示其在飞蝗卵发育和卵巢生长中的功能。【方法】基于前期获得的第1个促性腺周期内飞蝗雌成虫脂肪体转录组数据,鉴定和聚类分析GPCR基因;qRT-PCR检测GPCR基因在卵黄发生期飞蝗雌成虫脑、胸腹神经节、脂肪体、卵巢和中肠的组织特异性表达模式;通过RNAi实验分析GPCR基因在卵发育和卵巢生长中的功能。【结果】在飞蝗雌成虫脂肪体转录组中新鉴定到了29个GPCR基因。qRT-PCR分析显示,PTH/PTHrPR1和MSR分别在飞蝗雌成虫脂肪体和胸腹神经节中显著高表达,Mthl4,Mthl6和GPR119L在中肠中显著高表达,Octβ1R,CrzR,CCAPR,LGR2,mGluR和GABABR在脑中的表达水平显著高于在其他组织中的。RNAi筛选发现敲降5个GPCR基因CCAPR,PTH/PTHrPR1,ADGRL3,Mthl15和DHR的表达显著抑制飞蝗初级卵母细胞发育和卵巢生长。【结论】本研究结果有助于揭示昆虫高繁殖力的...     

Anatomical Characteristics of Leaves and Woods of Fagus lucida and Their Relationship to Ecological Factors in Mountain Fanjingshan,Guizhou, China

An eco-anatomic study on leaves and woods of Fagus lucida Rehd. et Wils., which grows at an elevation of 1 260～2 020 m above sea level in Mountain Fanjingshan, Guizhou Province of Southwestern China, was carried out. Anatomical characteristics of leaves (including the thickness of upper epidermis, palisade mesophyll, spongy mesophyll, lower epidermis and lamina) and woods (vessel length, vessel width, vessel frequency, fiber length, ray width, ray height and ray frequency), and leaf surface characters (stomatal density, stomatal width and stomatal length) were determined and compared along the latitudinal gradient. As the results, 1) Lamina thickness was between 119.2 and 364.3μm; 2) Vessel frequency 75.2～133.6 per mm , vessel width 50.7～85.6 μm, vessel length 479.8～748.6 μm; fiber length 936.4～1 326.9 μm; total frequency of single and muhiseriate rays 6～9 per mm; 3) No solitary trichome was found on mature foliage, and the stomatal density was 72～113.6 per mm . Climatic indices at different altitudes were obtained by means of climatological method. Multi-statistical analysis was used to clarify the relationship between the morphological characters of the leaves and woods and climatic factors. The results showed that: 1 ) The thickness of palisade mesophyll, lower epidermis and lamina, and the vessel width increased with the humid/ add index (Bailey’s index); 2) With an increase of annual precipitation, spongy mesophyll thickness, vessel length and fiber length increased, but vessel frequency and stomatal density decreased; 3) Morphological features of leaves were closely related to low winter temperature, namely, lamina thickness decreased with coldness index, and the stomatal size decreased as the increase of mean temperature of the coldest month.