藏羚羊5个微卫星标记的多态性分析

藏羚羊是我国青藏高原的特有物种.为分析藏羚羊独特的遗传变异特征和核DNA遗传多样性,以5个微卫星标记对50只藏羚羊的等位基因多态性进行了研究.研究结果表明:5个微卫星标记共检测到92个等位基因,每个标记的平均等位基因数为18.4个(在16~23之间),平均有效等位基因数为11.1;5个微卫星标记的多态信息含量均在0.8573以上,为高度多态标记,其中L03标记的多态信息含量最高,达0.9372;各标记的观测杂合度在0.4898~0.9091之间,期望杂合度在0.8770~0.9504之间,平均期望杂合度为0.8990,属于高度杂合标记,遗传变异丰富.这些筛选出的多态性微卫星标记可应用于藏羚羊遗传多样性、遗传结构分析及遗传图谱的构建等工作.     

Neuronal and glial markers of the central nervous system

Summary This brief review evaluates the expression of cell-specific markers on differentiated neural cells and, where necessary, on their developing precursors. Within these limitations only the commonly used markers are discussed and those deemed unequivocal are only briefly appraised.     

On the Pragmatic Function of ＂Well＂ in Friends

Some little words such as ＂well＂ are essential to successful communication and the proper use of them is of great importance. The author classifies the pragmatic function of ＂well＂ in Friends into 4 categories, illustrating them with examples.     

Construction of a BAC library from cucumber (Cucumis sativus L.) and identification of linkage group specific clones

A bacterial artificial chromosome (BAC) library consisting of 19,200 clones with an average insert size of 105 kb has been constructed from a cucumber (Cucumis sativus L.) inbred line S94; derived from a cultivar in North China. The entire library was equivalent to approximately 5 haploid cucumber genomes. To facilitate chromosome engineering and anchor the cucumber genetic linkage map to its chromosomes, 15 sequence-characterized amplified regions (SCAR) and seven simple sequence repeats (SSR) markers from each linkage group of cucumber were used to screen an ordered array of pooled BAC DNA with polymerase chain reaction (PCR). Fifteen markers gave at least two positive clones. As a result, 32 BAC clones representing 7 linkage groups of cucumber were identified, which further validated the genome coverage and utility of the library. This BAC library and linkage group specific clones provide essential resources for future research of the cucumber genome.     

梨遗传转化与遗传标记研究进展

用遗传转化的方法对梨进行遗传改良和用分子生物学的方法研究梨的遗传性状是当今梨科研的热点,基因型、抗菌肽的活性与稳定性、农杆菌的侵染力等是影响梨遗传转化的重要因素．DNA的提取方法决定DNA的数量和质量,直接影响分子生物学方法在梨中的应用和应用结果．本文综合有关文献综述了国内外梨遗传转化和遗传标记研究所取得的进展,并结合存在的问题对今后的工作重点提出了几点建议．     

基于FLARToolkit的多标识增强现实系统的实现

针对传统增强现实系统采取单个标识识别影响其在PC端开发效率的问题.选择新兴的基于Flash的跟踪类库FLARToolkit,结合3D引擎Papervision 3D,开发实现了具有多个模板标识的增强现实系统原型,附上了底层代码和系统结果,并针对其中的光学畸变问题采用棋盘法进行改善,成功将摄像头标定误差降低到0.093.提高增强现实系统的稳定性的同时,也为进一步开发提供了良好的基础.     

肢带型肌营养不良一家系致病基因排除性定位

为了定位一个常染色体显性遗传肢带型肌营养不良家系的致病基因（ADLGMD）,采用13个荧光微卫星标记对收集到的一个包括4代33人的ADLGMD家系进行连锁分析,所选择的标记覆盖了3个已知ADL—GMD致病基因位点和4个已报道的致病基因定位区段．通过Linkage 5．1软件包计算连锁概率,各位点连锁分析所得的LOD值均小于-3,显示该家系致病基因与这7个位点均不连锁．该家系的肌营养不良症致病基因不在已知的位点内,很可能是一个新致病基因．     

利用RAPD技术进行野生大豆种群内分化的研究

利用RAPD技术对25°N野生大豆种群16个样本进行分子标记.从150多个RAPD引物中筛选出具有多态性的引物20个,共扩增出146条带,其中具有多态性带60条,点40.8%.平均遗传距离为0.1536;杂合度为0.3248,聚类分析结果表明25°N野生大豆16个样本分成4类,种群内存在大量的遗传变异,本实验为研究野生大豆种群内及进一步研究种群间的遗传多态性探索了一种可行的方法,并对野生大豆核心质资源的保存及取样策略进行了讨论.     

Isolation and genetic characterization of a fragile plant mutant in rice (itOryza sauva) L.

The fragile rice mutant was isolated from an M₂ population of indica variety Shuang Ke Zao (SKZ) treated with g-rays, and designated as fp1 (fragile plant 1) because of its fragile leaves and culms. To map FP1 locus, an F² mapping population was derived from a cross between the fp1 and C-bao, a polymorphic japonic variety. The primary mapping result places the FP1 locus in an interval between two molecular markers, microsatellite marker RM16 (3.1 cM proximal to FP1) and STS marker G144a (9.1 cM distal to FP1) in the centromere region of chromosome 3. A CAPS marker C524a was further developed between RM16 and G144a, with 0.4 cM genetic distances to the FP1locus, providing a practical starting point for constructing a BAC contig spanning the FP1 locus and cloning the fp1 gene. Allelism test demonstrated that fp1 is allelic to bc1, a fragile rice mutant reported previously.     

Identification of an AFLP marker linked to the stripe rust resistance geneYr10 in wheat

AFLP analysis of near-isogenic lines of the stripe rust resistance gene Yr10 was carried out with 6 PstⅠ- primers and 10 TaqⅠ-primers with the donor parent of Yr10 gene as the check. A total of about 4200 distinguishable bands were amplified, of which 5 were stable. The genetic linkage of the 5 polymorphic DNA fragments with the target gene were tested preliminarily on a segregating F₂ population derived from a cross between the gene donor parent “Moro” and susceptible cultivar “Mingxian 169”. The DNA fragment PT0502 was found closely linked to the Yr10 gene and cloned and sequenced. Based on the sequence specific primers for PCR were designed and synthesized. Genetic linkage analysis with 195 segregating F₂ plants indicated that the genetic distance was 0.5 cM between the main product SC₂₀₀ fragment produced by PCR with the primers and the Yr10 gene. The primers can be used to detect the Yr10 gene quickly, effectively and exactly.