Zinc in plants

Zinc (Zn) is an essential component of thousands of proteins in plants, although it is toxic in excess. In this review, the dominant fluxes of Zn in the soil-root-shoot continuum are described, including Zn inputs to soils, the plant availability of soluble Zn(2+) at the root surface, and plant uptake and accumulation of Zn. Knowledge of these fluxes can inform agronomic and genetic strategies to address the widespread problem of Zn-limited crop growth. Substantial within-species genetic variation in Zn composition is being used to alleviate human dietary Zn deficiencies through biofortification. Intriguingly, a meta-analysis of data from an extensive literature survey indicates that a small proportion of the genetic variation in shoot Zn concentration can be attributed to evolutionary processes whose effects manifest above the family level. Remarkable insights into the evolutionary potential of plants to respond to elevated soil Zn have recently been made through detailed anatomical, physiological, chemical, genetic and molecular characterizations of the brassicaceous Zn hyperaccumulators Thlaspi caerulescens and Arabidopsis halleri.     

基于生物信息学技术筛选影响胶质母细胞瘤化疗敏感性 相关基因的研究

目的:应用生物信息学技术筛选影响胶质母细胞瘤(GBM)化疗敏感性的相关基因。方法:对2批胶质瘤患者BIOSTAR基因芯片进行分析。通过随访完善临床资料,筛选芯片中胶质母细胞瘤患者生存期长、短两组间的差异基因,明确差异基因参与的功能和通路,并构建与烷化剂相关基因的信号传导网络,结合芯片数据、患者预后和信号传导网络,筛选GBM化疗敏感性的相关基因。结果:两组芯片中间差异基因有503条。2批芯片的差异基因主要参与62项基因功能,主要参与31条信号传导通路。通过对差异基因功能、通路,烷化剂信号转导网络的分析,得到影响胶质母细胞瘤化疗敏感性的核心的差异基因IFNGR2、IL8、ITGA5、TNFRSF1B。结论:通过严谨的实验设计和科学的统计学判别,结合患者完整的生存资料,本研究成功地应用生物信息学技术对基因芯片的大量数据进行挖掘和分析,并筛选出了可能影响GBM患者预后和化疗药物敏感性的基因,为进一步功能实验和患者个体化治疗奠定了基础。     

Monosomy 9pter and trisomy 9q34.11qter in two sisters due to a maternal pericentric inversion

Pericentric inversions of chromosome 9 leading to unbalanced live-born offspring are relatively rare and so far only four cases have been reported. Here we present two sisters with an unbalanced recombinant chromosome 9 which resulted from a large maternal pericentric inversion inv(9)(p24.3q34.1). Further molecular characterisation of the aberrant chromosome 9 by 250k SNP array analysis showed a terminal 460 kb loss of 9p24.3 and a terminal 8.9 Mb gain of 9q34.11. We compared the clinical features of these two patients with the previous reported four cases as well as with patients with similar sized 9pter deletions or 9qter duplications. Based upon this study, we suggest that the recombinant chromosome 9 phenotype is mainly the result of duplication of a 3.4 Mb region of chromosome 9q34.11q34.13.     

花生种皮抗黄曲霉差异基因表达分析

选择高抗黄曲霉花生种质J11与高感种质金花1012为研究材料,利用基因芯片技术开展了抗病差异基因表达分析研究。试验共使用61078组大豆杂交探针。初步结果表明,与金花1012相比,J11种皮共有417个差异基因表达量上升,650个差异基因表达量下降,其中两份种质的种皮过氧化物酶（POD）差异基因表达量存在明显差异。为初步验证基因芯片分析结果,进行了POD活性测定。结果表明,种子接近成熟前,J11种皮的POD活性迅速上升,明显高于金花1012水平;金花1012则变化不明显,与相关基因差异表达量基本一致。     

几种基因芯片技术的比较

基因芯片技术因其自身的优越性将成为基因组序列分析和基因表达研究的主要工具。但是由于不同的实验室使用不同的技术平台 ,从 2 5到 80个碱基的寡核苷酸芯片和长度从数百到几千个碱基的cDNA阵列。不同技术平台的存在 ,为芯片资料的利用和芯片领域的标准化分析带来了困难。通过对不同技术平台的研究比较 ,短的和长的寡核苷酸芯片技术具有明显的优势 ,可望成为将来主要的技术方法。     

基因芯片技术及其应用研究

基因芯片技术是建立在杂交序列基本理论上的分子生物学技术,具有高度平行性、多样性、微型性和自动化的特点。由于其克服了传统核酸印迹杂交技术操作复杂、自动化程度低、检测效率低等缺点得以飞速发展,目前,该技术已用于DNA测序、基因表达分析、新基因的发现、基因单核苷酸多态性(SNPs)研究、基因诊断、药物筛选等领域。