多倍体植物中基因表达模式的变化

植物杂交和多倍化能导致基因组结构发生变化,并显著影响了基因表达,因此认为杂交和多倍化是促进植物进化的一个重要力量。近些年大量的研究表明植物多倍化后基因表达模式发生了复杂的改变,包括基因沉默、基因表达的基因组偏向性及组织特异性、基因激活等现象,本文对这些现象及其特点和机制进行了综述。     

人血小板生成素重组载体的构建与体外表达

应用基因克隆技术,以人ＴＰＯｃＤＮＡ为目的基因,构建真核细胞表达重组体ＶＲＴＰＯ,藉脂质体将其转染于ＮＩＨ３Ｔ３细胞,应用ＰＣＲ、ＲＴ－ＰＣＲ及Ｗｅｓｔｅｒｎ印迹等技术对其转染及表达情况进行鉴定．结果表明：ＶＲＴＰＯ构建成功,在ＮＩＨ３Ｔ３细胞可表达人ＴＰＯ,为应用人ＴＰＯｃＤＮＡ进行质粒ＤＮＡ骨骼肌直接注射于动物体内的基因治疗研究奠定了基础     

基因系统生态及其应用

运用基因生态系统观点,探讨了基因的行为生态,提出了基因具有整体性、联系性、有序性和平衡性等特性．还讨论了基因生态的应用及其发展前景．     

人新基因HBRP基因工程细胞系的建立

在研究牛精浆蛋白 (bovineseminalplasmaproteins ,BSPproteins)及其相关蛋白在受精卵发育过程中的重要作用时 ,在人睾丸组织中发现并克隆了一个与BSP蛋白相关新基因的序列 ,其开放阅读框架 (openreadingframe ,ORF)编码了一个含 2 2 3个氨基酸残基的蛋白质 ,氨基酸序列中含有4个纤连蛋白Ⅱ型结构域 ,与BSP蛋白在结构上有一定的相似性 ,称其为人BSP相关蛋白 (humanBSP relatedprotein ,HBRP) ,并在GenBank注册 ,登录号为AF2 791 4。预测该蛋白是与BSP蛋白功能相关的结合蛋白 ,并已成功地将该基因定位在 1 9号染色体 1区 3带上。为进一步研究该新基因的生物学功能 ,利用重组质粒pEGFP C2 HBRP转染人胚肾HEK2 93细胞 ,通过G41 8筛选出药物抗性克隆 ,建立了稳定的基因工程细胞系 ,为该基因功能的研究奠定了基础 ,对该基因功能的进一步研究有重要的意义 义。     

基因工程技术在花卉中的应用

近年来花卉产业得到了蓬勃发展,不断成熟的基因工程技术为花卉的品质改良提供了新的思路,也为花卉产业化发展带来了新的机遇。本文综述了影响植物花色、花型、花期等相关基因及转基因的研究,展望了基因工程技术在花卉育种和产业化应用的发展前景。     

Gene structure and chromosomal localization of mouse cyclin G2 (Ccng2)

Cyclins are essential activators of cyclin-dependent kinases (Cdk) which, in turn, play pivotal roles in controlling transition through cell-cycle checkpoints. Cyclin G2 is a recently discovered second member of the G-type cyclins. The two members of the G-type cyclins, cyclin G1 and cyclin G2, share high structural similarity but their function remains to be defined. Here we characterize the structure of the mouse cyclin G2 gene by first cloning and sequencing the full-length mouse cyclin G2 cDNA. The cyclin G2 cDNA was used to isolate the cyclin G2 gene from a BAC library and to establish that the gene was transcribed from eight exons spanning a total of 8604 bp. The cyclin G2 gene was mapped by fluorescence in situ hybridization (FISH) to mouse chromosome 5E3.3.–F1.3. This region is syntenic to a region on human chromosome 4. The expression of cyclins G1 and G2 was examined in various tissues, but no correlation between expression patterns of the two genes was observed. However, during hepatic ontogenesis the cyclin G2 expression level decreased with age, whereas cyclin G1 expression increased. Transient expression of cyclin G2-green fluorescent protein (GFP) fusion protein in NIH3T3 cells showed that cyclin G2 is essentially a cytoplasmic protein, in contrast to the largely nuclear localization of cyclin G1. Our data suggest that, despite the close structural similarity between mouse cyclins G1 and G2, these proteins most likely perform distinct functions.     

代谢工程中基因修饰与基因表达的工具

代谢工程利用重组DNA技术导入定向改造的基因 ,以改进微生物细胞的某些代谢特性 ,已经发展成为一个工业微生物育种和优化发酵过程的强有力工具。基因的修饰与表达是代谢工程的重要组成部分。本文介绍了近年来代谢工程中基因修饰与表达所用的工具方面的进展。     

基因芯片技术在甘蔗研究中的应用进展

基因芯片技术是新生代的生物技术,具有大规模平行处理生命信息的能力.基因芯片具有高通量、并行性、微型化与自动化的特点,因此成为探究功能基因组学最有效的方法之一,已引起全世界广泛的关注和重视,在许多领域得到了广泛的应用.甘蔗是世界上急需研发的重要能源作物,基因芯片对甘蔗研究有重要的意义.本文简介了基因芯片技术的原理和制备过程,并着重阐述了在甘蔗抗旱、抗病、基因表达和miR-NA鉴定方面的应用进展.     

Gene structure and chromosomal localization of mouse cyclin G2 (Ccng2)

Cyclins are essential activators of cyclin-dependent kinases (Cdk) which, in turn, play pivotal roles in controlling transition through cell-cycle checkpoints. Cyclin G2 is a recently discovered second member of the G-type cyclins. The two members of the G-type cyclins, cyclin G1 and cyclin G2, share high structural similarity but their function remains to be defined. Here we characterize the structure of the mouse cyclin G2 gene by first cloning and sequencing the full-length mouse cyclin G2 cDNA. The cyclin G2 cDNA was used to isolate the cyclin G2 gene from a BAC library and to establish that the gene was transcribed from eight exons spanning a total of 8604 bp. The cyclin G2 gene was mapped by fluorescence in situ hybridization (FISH) to mouse chromosome 5E3.3.–F1.3. This region is syntenic to a region on human chromosome 4. The expression of cyclins G1 and G2 was examined in various tissues, but no correlation between expression patterns of the two genes was observed. However, during hepatic ontogenesis the cyclin G2 expression level decreased with age, whereas cyclin G1 expression increased. Transient expression of cyclin G2-green fluorescent protein (GFP) fusion protein in NIH3T3 cells showed that cyclin G2 is essentially a cytoplasmic protein, in contrast to the largely nuclear localization of cyclin G1. Our data suggest that, despite the close structural similarity between mouse cyclins G1 and G2, these proteins most likely perform distinct functions.     

pcDNA3.1(+)-VEGF165载体的构建及表达蛋白特性分析

构建含人VEGF165基因的重组真核表达质粒,并对其表达蛋白特性进行初步分析。将合成的VEGF165基因序列克隆至pCR2.1-TOPO载体,测序鉴定证实基因碱基序列无误后,再克隆至真核表达载体pcDNA3.1(+),构建成pcD-NA3.1(+)-VEGF165重组质粒。利用DNAstar软件分析基因序列并翻译成氨基酸序列,再用ExPASy protscale和Protean软件分析其疏水特性、蛋白二级结构。经基因测序、酶切鉴定和PCR鉴定证实pcDNA3.1(+)-VEGF165重组质粒构建成功。Ex-PASy protscale和Protean软件分析表明VEGF165蛋白具有较好的水溶性。本研究为VEGF165的基因治疗应用和VEGF165蛋白直接治疗勃起功能障碍奠定了基础。     

Molecular Therapy and Prevention of Liver Diseases

Molecular analyses have become an integral part of biomedical research as well as clinical medicine. The definition of the genetic basis of many human diseases has led to a better understanding of their pathogenesis and has in addition offered new perspectives for their diagnosis, therapy and prevention. Genetically, human diseases can be classified as hereditary monogenic, acquired monogenic and polygenic diseases. Based on this classification, gene therapy is based on six concepts (1) gene repair, (2) gene substitution, (3) cell therapy, (4) block of gene expression or function, (5) DNA vaccination and (6) gene augmentation. While major advances have been made in all areas of gene therapy during the last years, various delivery, targeting and safety issues need to be addressed before these strategies will enter clinical practice. Nevertheless, gene therapy will eventually become part of the management of patients with various liver diseases, complementing or replacing existing therapeutic and preventive strategies.     

Molecular therapy and prevention of liver diseases

Molecular analyses have become an integral part of biomedical research as well as clinical medicine. The definition of the genetic basis of many human diseases has led to a better understanding of their pathogenesis and has in addition offered new perspectives for their diagnosis, therapy and prevention. Genetically, human diseases can be classified as hereditary monogenic, acquired monogenic and polygenic diseases. Based on this classification, gene therapy is based on six concepts: (1) gene repair, (2) gene substitution, (3) cell therapy, (4) block of gene expression or function, (5) DNA vaccination and (6) gene augmentation. While major advances have been made in all areas of gene therapy during the last years, various delivery, targeting and safety issues need to be addressed before these strategies will enter clinical practice. Nevertheless, gene therapy will eventually become part of the management of patients with various liver diseases, complementing or replacing existing therapeutic and preventive strategies.     

基因芯片技术检测拉美夫定相关的HBV变异

美夫定(Lamivudine)是新一代核苷类似物,能够迅速降低慢性乙型肝炎病人的血清HBV DNA水平,但是Lamivudine治疗12个月后,14%～39%的患者都会出现抗药性[1～3],病情会有反复,用药不再有效.已有的研究表明,通过检测患者血液中的病毒突变情况,轮流使用干扰素,Lamivedine,FamcicLovir丙种球蛋白等,可以得到很好的治疗效果[4].本研究中,我们采用拉美夫定耐药位点基因芯片,对44例慢性乙型肝炎病人进行了HBV突变检测,并应用传统的DNA测序的方法进行验证,结果报告如下.     

利用基因工程改良植物类胡萝卜素的合成

类胡萝卜素(carotenoids)是植物体内存在的一类重要天然色素物质的总称,其生物功能广泛.类胡萝卜素是人类饮食结构中重要的组成部分,并且在医药、化妆品及食品与饲料工业等方面扮演着重要的角色.类胡萝卜素还是一些维生素合成的前体,具有多种保健功能,可以提高人体免疫力,并具有抗癌的功效.目前有大量关于提高植物体内类胡萝卜素含量及定向改变其种类的研究,对类胡萝卜素代谢途径及其调控的理解是这些研究的基础.主要阐述植物天然类胡萝卜素的生物合成及利用基因工程对类胡萝卜素改良的研究进展.     

Mapping of genes on the linear chromosome of the bacterium Borrelia burgdorferi: Possible locations for its origin of replication

Molecular clones of Borrelia burgdorferi, aetiologic agent of Lyme borreliosis, were isolated and analysed by DNA sequence determination. This procedure yielded B. burgdorferi homologues of gidA, gyrB, gyrA, ftsA and ftsZ. The genes were located on the physical map of the B. burgdorferi linear chromosome. Also mapped were the genes fla and p60 while dnaA was mapped using a heterologous probe. gyrA and gyrB were found to be in tandem and were mapped, along with dnaA at the centre of the chromosome. gidA was located close to the left hand extremity of the chromosome. Because gyrB, dnaA and gidA are normally located within 50 kb of the origin of replication (oriC), we propose two possible sites for oriC in the B. burgdorferi linear chromosome.     

小鼠白细胞介素4基因的化学合成、克隆与表达

利用381A型DNA合成仪,分29个寡聚核苷酸片段化学合成了小鼠IL-4全基因,共442bp。以pUC12质粒作为载体,将所有合成片段分前后两组进行磷酸化、退火、连接和克隆,经过菌落原位杂交、酶切鉴定和质粒DNA序列分析,分别得到了含有小鼠IL-4前后两半基因片段的两种重组质粒,回收前半基因片段,插入到含有后半基因重组质粒的EcoRI和PstI酶切位点之间,成功地得到了含有小鼠IL-4全基因的重组质粒pFR101。将全合成基因插入到质粒pSM53中,得表达质粒pFR105,转化大肠杆菌TAP106,根据IL-4对CTLL细胞的作用,肯定了TAP106(pFR105)细菌中有小鼠IL-4活性蛋白的表达。     

基因突变的分子检测技术

基因突变的分子检测是确定生物性状与某种遗传变异的关系、探讨生物物种内基因的差异、了解生物种间亲缘和进化的关键技术,对群体遗传学和生物分类学研究、遗传病诊断等都有着重要的理论意义和实用价值。因此,对于基因突变的检测方法的研究目前受到广泛关注。对基因突变的形式及其分子检测技术作了全面综述。     

DDR2基因缺失小鼠的繁育及子代基因型的鉴定

目的：探讨盘状结构域受体2（DDR2）基因缺失小鼠的优化繁殖方法与子代小鼠DDR2基因型的鉴定方法,建立DDR2基因缺失小鼠模型,为进一步研究DDR2分子在肿瘤、肺纤维化、类风湿性关节炎等复杂疾病中的功能以及作用机制奠定基础。方法：将从美国JAX实验室引进的三对杂合子小鼠进行饲养并交配繁殖,繁殖成功后其子代中将会出现野生型、杂合子以及纯合子3种基因型。用基因组提取试剂盒试剂盒提取子鼠鼠尾的基因组DNA,经紫外分光光度计定量后,采用Taqman qPCR的方法准确鉴定出小鼠的基因型,同时观察子代小鼠各基因型的比例,并通过小鼠体态观察,进一步证实Taqman qPCR鉴定方法的可靠性。结果：DDR2基因杂合子小鼠互交繁殖可得到DDR2野生型小鼠、DDR2纯合子小鼠以及DDR2杂合子小鼠三种基因型小鼠,所得子代基本符合孟德尔遗传规律,且雌性和雄性DDR2纯合子小鼠体长均较DDR2野生型小鼠和DDR2杂合子小鼠小,鼻子也较其它基因型小鼠明显变短,无繁殖能力。依据Taqman qPCR的结果所得出的纯合子小鼠体貌特征与文献报道一致,证实了Taqman qPCR结果的可靠性。结论：雌、雄性DDR2杂合子小鼠交配可有效获得DDR2基因缺失小鼠;实验所用Taqman qPCR方法能够准确鉴定子代小鼠的基因型,DDR2纯合子小鼠的获得为后续实验的提供了较理想的动物模型。     

Gene Diversity, Gene Differentiation Coefficients of Parent Populations and Prediction of Their F_1 Heterosis

1IntroductionThepredictionofheterosisisveryimportantinbreeding.Atearlystage,scientistspaidgreatattentiontopredictheterosisbyusinggeneticdistancebasedonqllantitativetraits.Butthiskindofdistanceisaffectedstronglybyenvironmentalfactors.Soitisdifficulttoreflecttheactualgeneticdifferencebetweenparentpopulations.Recently,scientistspaymoreattentiontopredictheterosiswithgeneticdistanceestimatedfromproteinandDNApolymorphisms.Thisisbecauseitcanreflectthegeneticdifferencebetweenpopulationstrulier.Inte…