增强原位杂交探针敏感性的研究

原位杂交(ISHH)属于固相分子杂交范畴,它是用标记的DNA或RNA为探针在原位检测组织细胞内特定核酸序列的方法.     

原位PCR技术及其应用

原位ＰＣＲ技术是通过在染色体上或组织细胞内对靶核酸序列进行原位扩增,用原位杂交技术检测,从而对靶核酸进行定性,定位和定量分析的研究方法,原位ＰＣＲ大大提高了原位杂交技术的灵敏度,在分子生物学基础理论和临床医学研究方面展示了美好的应用前景。     

人Y染色体特异DNA片段的原位PCR扩增

报道了以人类外周血白细胞为材料,利用人类Y染色体特异片段一对扩增引物Y3和 Y₄,在玻片细胞样品上进行原位 PCR获得的结果.用Dig-11-dUTP于原位PCR过程中直接掺入法(直接原位PCR)和细胞原位PCR后再作原位杂交的方法(间接原位PCR)都证明:玻片上细胞样品内的Y染色体特异DNA片段有明显的原位扩增.并对原位PCR的专一性与可重复性,细胞内PCR扩增产物的存留等方法学问题,以及原位PCR技术的价值和应用前景进行了讨论.     

一种新型细胞微阵列的制作和应用

为了高通量地检测大量培养细胞中基因原位表达, 发明了一种制作细胞微阵列的新方法,成功地制作含20种细胞系共100个供体细胞石蜡混合物点阵的细胞微阵列.免疫组化检测P53, P21, PTEN、P16基因在细胞微阵列中的蛋白质表达.原位杂交检测BRD7、NGX6 基因在细胞微阵列中mRNA原位表达.建立了P53、P21、PTEN、P16蛋白和BRD7、NGX6 mRNA 在不同培养细胞中的原位表达谱.细胞微阵列为基因功能研究提供一种新的高通量工具.细胞微阵列可广泛用于DNA、RNA和蛋白质水平上的基因原位表达研究.细胞微阵列还可用于筛选药物作用靶标的研究.     

原位PCR技术及其应用前景

原位PCR是分子生物学领域中一种崭新的技术,它结合了PCR技术和原位杂交技术的优点.该文介绍了原位PCR技术的起源、发展及方法学,并简要描述了该技术的应用现状及前景．     

UBC家族新成员UBF基因的组织表达谱研究

目的和方法:提取人胎肝和HL-60细胞总RNA,采用RT-PCR的方法,从中扩增UBF基因,并对扩增产物进行测序,从而证实UBF基因的天然存在性;采用原位杂交的方法研究UBF在5月龄胎儿的不同组织及HL-60细胞中的表达谱及亚细胞定位.结果:从胎肝和HL-60细胞中均扩增得到了完整的UBF基因,且其序列与注册序列完全一致;原位杂交结果显示UBF在人胚胎多种组织中表达,其中胎骨骼肌表达最强,胎肾最弱.结论:UBF基因,作为Ubc家族的一个新成员,在人胚胎的骨骼肌、肝脏、肾脏、心脏和肺中均有表达,且骨骼肌中的表达最强.     

人单拷贝及重复DNAF序列的原位PCR

在培养的人小肠癌转移腹水细胞系细胞中进行了Ｙ染色体特异的重复序主单 拷贝序列的原位扩增与检测,结果显示原位ＰＣＲ法的灵敏度比直拉的原位杂交法明显提高。     

薏苡45S和5S rDNA的染色体定位研究(简报)

通过荧光原位杂交的方法确定了45S和5S正NA序列在薏苡前中期染色体上的位置.尽管具有20条染色体的薏苡是四倍体植物,但它的基因组中只有一个45S和5S rDNA位点.根据薏苡前中期染色体的核型,确定45S rDNA序列位于薏苡第2号染色体短臂上的次级缢痕区和随体上,5S rDNA序列位于第7号染色体长臂靠近着丝粒处,5S rDNA位点到着丝粒的百分距离是29.13±1.76.     

大鼠睾丸发育过程中促甲状腺激素释放激素受体mRNA的表达

为研究促甲状腺激素释放激素受体(TRHR)在大鼠睾丸组织中的表达规律和在生殖发育调节中的作用,依据大鼠垂体中的TRH-RcDNA设计引物,采用RT-PCR法从大鼠睾丸组织中获得了TRH-R的cDNA克隆,测序表明其核苷酸序列与大鼠垂体中的TRH-RcDNA序列完全一致.应用非放射性原位杂交(NR-ISH)技术观察TRH-RmRNA在大鼠睾丸中的定位,结果显示杂交信号集中在间质细胞中,生精细胞无杂交信号.利用实时动态定量RT-PCR法观察了TRH-R在不同发育阶段大鼠睾丸中的表达变化,发现在睾丸间质细胞发育的初期阶段(第8天),没有TRH-R的表达,但从第15天起能观察到TRH-R的表达,并且表达量在20天、35天、60天、90天逐渐增加.这些结果表明,大鼠睾丸组织间质细胞能特异性表达TRH-R,并且表达量与发育过程相关.     

原位杂交及原位PCR检测幽门螺杆菌

本研究建立了检测幽门螺杆菌的原位杂交和原位ＰＣＲ技术,采用ＰＣＲ掺入的方法标记原位杂交的生物素探针,６份ＨＰ阳性胃活检组织冰冻切片杂交均为阳性,６份阴性对照组织为阴性。９／１２份ＨＰ阳性对照组织石蜡切片杂交阳性,２份阴性对照切片为阴性。３份阳性对照猫胃粘膜冰冻切片杂交也是阳性。原位ＰＣＲ的引物来自ＨＰ的１６ｓｒＲＮＡ基因,在扩增过程掺入生物素基因。４／４例ＨＰ阳性人胃粘膜冰冻切片原位扩增阳性,２／     

多彩色荧光原位杂交技术原理及其应用

多彩色荧光原位杂交是一门新兴的分子细胞遗传学技术,它用几种不同颜色的荧光素单独或混合标记的探针,进行原位杂交,同时检测间期细胞或中期细胞中的几个特异核酸序列,为分析癌症遗传不稳定性提供了一种简便、快速、可靠的方法,并广泛应用于物理图谱绘制、致突变研究、肿瘤病理学和产前诊断.     

NGX6基因在多种常见癌组织中的原位表达及其临床意义的研究

研究新的候选抑瘤基因NGX6在多种常见癌组织中的mRNA原位表达谱,分析NGX6 mRNA阳性率与肿瘤1临床病理特征的关系并评估其作为肿瘤转移、预后预测分子标志物的有效性.利用已制作的多肿瘤组织和鼻咽癌组织微阵列,原位杂交检测NGX6 mRNA在多种常见癌组织中的阳性率.结果显示.NGX6 mRNA在鼻咽癌、肺癌、胃癌和结、直肠癌中的阳性率低于其对应的正常组织(P＜0.05,P＜0.01).淋巴结转移性鼻咽癌、肺癌、结、直肠癌和喉癌组织中的NGX6 mR.NA阳性率显著降低(P＜0.05,P＜0.01).NGX6 mRNA阳性率与鼻咽癌、肺癌和结、直肠癌临床分期有关,临床Ⅱ期、Ⅲ期或Ⅳ期癌组织NGX6 mRNA阳性率明显低于其相应的临床Ⅰ期癌(P＜0.05,P＜0.01).研究表明,鼻咽癌、肺癌、胃癌和结、直肠癌中存在低水平的NGX6 mRNA,NGX6 mRNA可作为鼻咽癌、肺癌和结、直肠癌侵袭、转移和临床进展预测的分子标志.     

从cDNA文库中筛选分析阳性克隆的简便方法

cDNA文库中阳性克隆的传统筛选分析法既费时又费力.利用微波炉加热的方法,简化了原位杂交中噬菌斑裂解、DNA变性与固定的程序;进一步运用PCR扩增技术,特异扩增克隆载体中插入的cDNA片段,加快了阳性克隆分析的进程.     

In situ localization of PCR-amplified DNA and cDNA

Combining the high sensitivity of PCR with the cell localizing ability ofin situ hybridization allows for the reproducible detection of low copy targets in intact cells. This article describes several key variables that include fixation, protease digestion, the hot start maneuver, stringency, and, for RNA analysis, DNase digestion that are important to successfulin situ PCR. Also stressed is the importance of performing and interpreting controls with each experiment. Important controls include omission of key components, use of samples known either to contain or lack the target of interest and, most importantly, the in-built controls invariably present in the heterogeneous component of any given tissue type.     

Strategies for signal amplification in nucleic acid detection

Many aspects of molecular genetics necessitate the detection of nucleic acid sequences. Current approaches involving target amplification (in situ PCR, Primed in situ Labeling, Self-Sustained Sequence Replication, Strand Displacement Amplification), probe amplification (Ligase Chain Reaction, Padlock Probes, Rolling Circle Amplification) and signal amplification (Tyramide Signal Amplification, Branched DNA Amplification) are summarized in the present review, together with their advantages and limitations.     

Molecular Cloning of a Novel Gene ZAhi-1 and its Expression Analysis during Zebrafish Gametogenesis

Proto-oncogen Ahi-1 is closely related to a lot of human and mouse diseases. Ahi-1 mutation will lead to leukemia in mice and Joubert syndrome in human beings. We have cloned the full cDNA sequence of Ahi-1 homologous in zebrafish, and RT-PCR results of ZAhi-1 in different tissues reveal that ZAhi-1 expressed highest in the mature gonad. In situ hybridization results of zebrafish gonad show that ZAhi-1 only expressed in the early stages’ gamete cells. RT-PCR analyses of mouse Ahi-1 in different stages of spermatogenesis have been done according to the published Ahi-1 sequence, and the findings reveal that Ahi-1 is expressed in gamete of pachytene stage. It can then be safely concluded that Ahi-1 might take place in the spermatocyte from the early pachytene stage to the late pachytene stage.     

High-resolution mapping of YACs and the single-copy gene Hs1pro−1 on Beta vulgaris chromosomes by multi-colour fluorescence in situ hybridization

Fluorescence in situ hybridization (FISH) is a powerful approach for physical mapping of DNA sequences along plant chromosomes. Nematode-resistant sugar beets (Beta vulgaris) carrying aBeta procumbens translocation were investigated by FISH with two differentially labelled YACs originating from the translocation. At mitotic metaphases, the translocation was identified with both YACs in the terminal region on a pair of chromosomes. Meiotic chromosomes, representing a far more extended hybridization target, were used to determine the orientation of YACs with respect to chromosomal domains in combination with chromosomal landmark probes for telomeres and centromeres. The in situ detection of plant single-copy sequences is technically difficult, and the wild beet translocation was used to explore the potential resolution of the FISH approach and to introduce the chromosomal mapping of single-copy genes into genome analysis of Beta species. An internal fragment of the nematode resistance gene Hs1 ^pro–1, 684 bp long, was detected on both chromatids of different Beta chromosomes and represents one of the shortest unique DNA sequences localized on mitotic plant chromosomes so far. Comparative chromosomal mapping of the 684 bp Hs1 ^pro–1 probe in the translocation line, a monosomic addition line and in B. procumbens revealed the origin of the wild beet translocation leading to nematode-resistant sugar beets.