中国仓鼠V79细胞系的oua~R和oua~S细胞蛋白质组分的双向电泳比较

作者用聚丙烯酰胺凝胶双向电泳,对中国仓鼠V79细胞系的乌本苷抗性突变型(oua~R)和野生型(oua~S)细胞的蛋白质组分进行比较,选择20个高度重复、分布均匀的肽斑作为参考标记,发现一些多肽在其位置、大小及密度上表现出差异,值得注意的是4小区(pI/MW为5.0/28～30kd)和6小区(pI/MW为6.3/39kd)的变化明显,提示这些多肽可能对V79细胞的oua~R是特异的,也许可作为oua~R细胞的特征性遗传标记。     

二甲基苯并蒽诱导金黄地鼠颊囊白斑癌变过程中血液流变特性的初步观察

人类口腔鳞状细胞癌约占整个口腔区域恶性肿瘤的90-95％，大多数学者认为．其发生多是由癌前病变发展而来．口腔白斑是最常见的口腔癌前病变，其发生及癌变与烟草等刺激密切相关．因此。采用烟草的主要有害成分之一的二甲基苯并蒽(DMBA)成功地在地鼠颊囊造成了白斑损害模型．近来．人们注意到，恶性肿瘤患者体内常存在血液流变特性的改变。     

人体正常骨及骨恶性肿瘤组织雌激素及孕激素受体分析

采用葡聚糖—活性炭单点饱和法测定38例人正常骨,35例骨恶性肿瘤组织胞浆雌激素受体(ER)和孕激素受体(PR)含量,结果显示,正常骨组织的平均ER量(12.37±9.89fmol/mg蛋白,单位下同,从略)明显高于骨恶性肿瘤组织ER均量(6.92±3.59)(P<0.01);PR均量在正常骨(14.03±7.87)和骨恶性肿     

穿梭质粒pZH32的构建

以pS189、pSV_2gpt、pMCi5为材料,构建了以EB病毒为基础,以酪氨酸tRNA琥珀突变校正基因SupF为靶基因,以黄嘌呤-鸟嘌呤磷酸核糖转移酶基因Eco gpt为选择标记基因的穿梭质粒pZH32。pZH32长9.4kb,克服了以SV40为基础的穿梭质粒自发突变率高以及宿主范围局限的缺点。SupF基因遗传背景清楚,长度126bp,便于进行序列分析。gpt基因使转化克隆的筛选更加方便。有利于建立一种化学诱变剂的分子检测系统,研究基因突变的类型和突变机制。     

中国仓鼠V79细胞系的oua^R和oua^S细胞蛋白质组分的双向电泳..

In the sense of gene expression, the primary and direct change in mutant cells should be involved in the protein component. Two-dimensional polyacrylamide gel electrophoresis has been used to compare the protein components of ouabain resistant mutant cells (ouaR) and sensitive wild type cells (ouaS) of chinese hamster lung cell line V79. The procedure is based on O'Farrell's method and we have made some modifications. In order to make the study reliable, we took twenty polypeptide spots as a reference marker. These marker spots could always be reproduced in a series of parallel experiments with both mutant and wild cells. In addition, these markers covered different small areas, representing different isoelectric point (pI) and molecular weight (MW) on the electrophoretogram. With reference to these marker spots, some polypeptide spots showed variations in their position, size and density. It is notable that the changes appeared in the small area 4 (pI/MW:5.0/28-30kd) and the small area (pI/MW:6.3/39kd) is highly reproducible and significant, so that these changes might be specific to ouabain resistant mutant of V79 cells. Since the level of genetic polymorphism of mammalian cells on two-dimensional gel electrophoresis is quite low, these specific changes might reflect the differences in gene structure and expression. This primary study should enhance the usefulness of two-dimensional gel electrophoresis for mutagenesis research with cultured mammalian somatic cells.     

pS189／FL CIII-2突变检测系统的研究

基于SV40的短暂复制型穿梭质粒pS189具有诸多优点：质粒分子小(5.3Kb)；在哺乳动物细胞中拷贝数高(10^5拷贝／细胞)：靶基因Sup F表型可在特定培养基上直接观察；全长仅160bp，易于作序列分析，且介于原核复制起始点和选择标记之间，降低了自发突变率．FL系人类非肿瘤性新生儿羊膜上皮细胞系，生物学背景清楚，易于培养，特别适合于病毒繁殖，     

穿俊质粒pZH32的构建

The shuttle vector can replicate in both bacteria and eukaryotic cells. We have constructed a shuttle vector pZH32 based on the EB virus. Three component parts of the plasmid come from pSV2gpt, pS189 and pMCi5. An E. coli tyrosine suppressor tRNA gene, supF, was used as a mutagenic target in this plasmid, and a gpt gene was used as a selectable marker gene for transformed cells. This pZH32 based on EBV replicates autonomously in the nuclei of human cells. It has a low background mutation frequency. The plasmid can be used to examine the mutagenic mechanism of potential mutagens and carcinogens in mammalian cells.     

THE ESTABLISHMENT OF pS189/FLCⅢ 2 SYSTEM FOR MUTAGENESIS STUDY

本文报道优选基于ＳＶ４０的短暂复制型穿梭质粒ｐＳ１８９和新生儿羊膜上皮细胞ＦＬＣⅢ—２亚克隆，组成穿梭质粒／哺乳动物细胞诱变检测系统。该系统中ＳｕｐＦ的自发突变型频率仅为１．７×１０－５，低于已报道的其它短暂复制型质粒和该质粒在其它细胞中复制时ＳｕｐＦ基因的自发突变率。各种剂量的ＭＮＮＧ的诱发突变频率随诱变剂剂量的增加而升高。ＭＮＮＧ对ＦＬ细胞毒性较大，仅０．３２μｇ／ｍｌ就可使ＦＬ几乎完全失去生长分裂形成克隆的能力，但在短时期内对依赖于病毒复制起点的ＤＮＡ复制效率影响不大，突变频率却显著升高。突变质粒的限制性内切酶分析和靶基因的ＰＣＲ分析等表明，检出突变大多数为点突变或微小缺失，该系统具有方便快速检出点突变的能力，可成为检测诱变剂、抗诱变剂作用强度和特性的分子检测系统。     

女性生殖系统不同组织雌激素及孕激素受体研究总结

用葡聚糖—活性炭单点饱和法测定人子宫颈癌177例(正常对照348例),子宫内膜癌344例(正常对照401例),卵巢恶性肿瘤289例(正常对照244例),外阴癌9例(正常对照9例)及4例输卵管癌组织胞浆的雌激素受体(ER)和孕激素受体(PR)含量。结果显示,子宫颈癌ER和PR平均含量分别为54.91±30.78和     

PCR技术在基因突变研究中的应用

1.PCR反应原理 多聚酶链反应(polymerase chain react-ion,PCR)是由kary Mullis及其同事们建立的一种体外核酸扩增方法,又有“无细胞的分子克隆”之称。它基于碱基互补原则,以待扩增的DNA片段为模板,在其两端加上与之互补的两段核苷酸引物,通过模板DNA在高温下变性、引物与其互补序列退火、用DNA聚合酶将退火的引物延长,这样反复进行的三步反应周期,每一周期的产物又可作为新的模板,进行新的合成反应,因此每个连续的周期使前一周期的合成产物