【摘要】 利用差异显示PCR技术获得的一条在胃癌和正常组织有差异表达的表达序列标签 (EST) W 12 3(GenBank登录号为AF15 0 6 31) ,通过与GenBank的dbest库进行电子杂交 ,选取了与其同源度高的若干EST ,在它们共有的保守序列设计了用于扩增的寡聚核苷酸引物 ,利用cDNA末端快速扩增PCR (RACE)技术得到了7条带有 polyA尾的 3′EST ,进行序列分析后 ,发现它们均是代表新基因或不同剪接体的EST ,且具有共同的保守序列 ,已登录GenBank .采用RNA印迹对目的序列进行初步鉴定 ,并进行了这些基因的组织分布分析 .RACE技术和生物信息学相结合 ,具有快速、高效的特点 ,有助于疾病相关基因的克隆 .更多还原

【Abstract】 Previously,an EST(expression sequence tag) fragment, W123 (Genbank accession No.AF150631) differentially expressed between gastric cancer and normal tissues, was cloned using differential display PCR technique. A few homologous EST sequences were captured when processing similarity search in human EST database. To search for additional W123 homologous genes in gastric tissue, a primer for 3′ RACE(rapid amplification of cDNA end) from highly conserved region among the above ESTs was designed and seven EST fragments with poly(A) tail were cloned. Compared with ESTs in GenBank, the seven EST fragments represented novel genes with a common sequence. Northern blot was applied to detect the expression of these genes between gastric cancer and normal tissues. The results suggested that a combination of bioinformatics and RACE technique is a rapid and effective method for seeking for disease related genes in specific tissue更多还原