We reported our preliminary study on mapping of the expressed sequence tag (EST) using single-stranded DNA conformation polymorphism (SSCP) on polymerase chain reaction (PCR) product. Five ESTs primer pairs, developed...We reported our preliminary study on mapping of the expressed sequence tag (EST) using single-stranded DNA conformation polymorphism (SSCP) on polymerase chain reaction (PCR) product. Five ESTs primer pairs, developed from nuclear genes including CAD(cinnamyl-alcohol dehydrgenase), CHS(chalcone synthase), NIR(nitrite reductase), ARA554 (cDNA expressed in differentiating xylem in Pinus taedae) and GS(glutamine synthetase), were selected to optimize the experimental protocol and generate mapping markers in the megagemtophytes from a single tree of Pinus massoniana. Our ultimate goal was to use SSCP approach to construct a transcriptional map for comparative mapping studies in P. massoniana. The efficiency to construct a transcriptional map in P. massoniana based on the published EST primer pairs derived from other pine species critically depended on the successful amplification of EST fragments and the ratio of the heterozygous loci revealed in P.massoniana. In this study, 3 (60) out of 5 tested EST primer pairs were succeeded in amplification, however, only 1(20) gene was heterozygous in the tested tree. The ratio of heterozygous loci detected in this study was similar to that revealed by anonymous marker in P.taeda. Therefore, a low efficiency would be expected if the map would be constructed using single pedigree. The segregation ratio of loci revealed by primer pairs would be higher if multiple pedigrees would be used. We proposed that consensus mapping approach based on multiple-pedigree should be used for EST mapping and therefore to increase the efficiency of EST mapping.展开更多
目的 研究大鼠肝癌变过程中几种癌基因的表达和c Ha ras 1点突变。方法 通过DEN诱发癌变启动模型和肝癌模型 ,应用免疫组化、原位杂交和MDT PCR SSCP分别观测癌基因的表达和c Ha ras1点突变。结果 c Ha ras和c myc基因的过表达参与...目的 研究大鼠肝癌变过程中几种癌基因的表达和c Ha ras 1点突变。方法 通过DEN诱发癌变启动模型和肝癌模型 ,应用免疫组化、原位杂交和MDT PCR SSCP分别观测癌基因的表达和c Ha ras1点突变。结果 c Ha ras和c myc基因的过表达参与了肝癌变的全过程 ,其中c Ha ras的过表达与癌前嗜碱性肝细胞灶、c myc基因的过表达与卵圆细胞增殖关系密切。IGF Ⅱ基因的过表达对癌前肝细胞增生灶 /结节向肝细胞癌的演进起重要作用。fms基因过表达仅与个别大鼠肝细胞癌有关。结论 大鼠肝癌变过程与c Ha ras、c myc、IGF Ⅱ和fms基因的过表达及c Ha ras1点突变有关 。展开更多
文摘We reported our preliminary study on mapping of the expressed sequence tag (EST) using single-stranded DNA conformation polymorphism (SSCP) on polymerase chain reaction (PCR) product. Five ESTs primer pairs, developed from nuclear genes including CAD(cinnamyl-alcohol dehydrgenase), CHS(chalcone synthase), NIR(nitrite reductase), ARA554 (cDNA expressed in differentiating xylem in Pinus taedae) and GS(glutamine synthetase), were selected to optimize the experimental protocol and generate mapping markers in the megagemtophytes from a single tree of Pinus massoniana. Our ultimate goal was to use SSCP approach to construct a transcriptional map for comparative mapping studies in P. massoniana. The efficiency to construct a transcriptional map in P. massoniana based on the published EST primer pairs derived from other pine species critically depended on the successful amplification of EST fragments and the ratio of the heterozygous loci revealed in P.massoniana. In this study, 3 (60) out of 5 tested EST primer pairs were succeeded in amplification, however, only 1(20) gene was heterozygous in the tested tree. The ratio of heterozygous loci detected in this study was similar to that revealed by anonymous marker in P.taeda. Therefore, a low efficiency would be expected if the map would be constructed using single pedigree. The segregation ratio of loci revealed by primer pairs would be higher if multiple pedigrees would be used. We proposed that consensus mapping approach based on multiple-pedigree should be used for EST mapping and therefore to increase the efficiency of EST mapping.
文摘目的 研究大鼠肝癌变过程中几种癌基因的表达和c Ha ras 1点突变。方法 通过DEN诱发癌变启动模型和肝癌模型 ,应用免疫组化、原位杂交和MDT PCR SSCP分别观测癌基因的表达和c Ha ras1点突变。结果 c Ha ras和c myc基因的过表达参与了肝癌变的全过程 ,其中c Ha ras的过表达与癌前嗜碱性肝细胞灶、c myc基因的过表达与卵圆细胞增殖关系密切。IGF Ⅱ基因的过表达对癌前肝细胞增生灶 /结节向肝细胞癌的演进起重要作用。fms基因过表达仅与个别大鼠肝细胞癌有关。结论 大鼠肝癌变过程与c Ha ras、c myc、IGF Ⅱ和fms基因的过表达及c Ha ras1点突变有关 。
