【摘要】 目的 检测甲基亚硝基脲诱导大鼠大肠肿瘤中抑癌基因ｐ５３变化。方法 应用ＰＣＲ，ＳＳＣＰ和ＳＳＣＰ和ＤＮＡ测序的方法。结果 经ＰＣＲ－ＳＳＣＰ分析，可见甲基亚硝基脲诱导大鼠大肠肿瘤中，出现ｐ５３基因单链的移位条带，且在第Ⅶ外显子；进一步做双链直接测序分析，见到ｐ５３蛋白编码序列的第２４４密码子的第３碱基Ｃ缺失。结论 实验结果提示大鼠暴露于致癌物甲基亚硝基脲后，产生了大肠肿瘤，且在分子水平上见到了抑癌基因ｐ５３突变。更多还原

【Abstract】 Objective We have examined tumor suppressor gene p53 from N- methyl - N- nitrosourea (MNU ) induced the col - orectal tumors in rats. Methods PCR, SSCP and DNA sequence analysis. Results In colorectal tumors induced by MNU, the mobil- ity shifts of p53 gene mutation were observed, p53 gene mutation was a deletion at third position C of codon 244 in exon7. Conclu- sion The present study suggested that MNU induces rat p53 mutations in the colorectal tumors.更多还原