【摘要】 p5 3突变体的显性负抑制效应(dominant negative effect)是指突变型p5 3蛋白抑制细胞内野生型p5 3蛋白发挥正常功能的一种特性,是肿瘤发生的重要原因之一.利用酵母中分离的等位基因功能分析技术(functional analysis of separated alleles in yeast,FASAY)建立了一种简便稳定的p5 3突变体显性负抑制效应检测和筛选方法,并应用于检测2 8例原发性肝癌组织(HCC)样本的p5 3单点突变体,发现了1 2例为显性负抑制效应突变体,其中突变位点Met2 4 6Val为首次报道具有显性负抑制效应.进一步分析这些突变p5 3蛋白的结构,发现这些具有显性负抑制效应的突变位点大多位于p5 3蛋白表面与DNA特异性序列相互作用的区域.更多还原

【Abstract】 Dominant negative effect of p53 mutations refers to the character of the certain mutant p53 proteins which could abolish the normal function of p53 protein translated from the wild-type p53 allele in heterozygous cells.So that is one of the most important reasons for the carcinogenesis.Here,based on FASAY(Functional Analysis of Separated Alleles in Yeast),an easily manipulated functional assay in yeast has been established and used to examine 28 single-nucleotide mutations obtained from primary HCC.Twelve out of them have been identified as dominant-suppressed mutation,and one of which,Met246Val,is the first time to be demonstrated having such dominant malfunction.The analysis of the distribution of mutations on the p53 protein further show that the most dominant-suppressed mutations were located on the surface of p53 protein interacting with the consensus DNA binging sites,but the ones without showing dominant effect mostly are located on the barrel-shaped scaffold,which initially elucidated the underlining mechanism in the aspect of protein structure correlating to the p53 dominant negative phenomena at cellular or genetic level.更多还原