高LET辐射致细胞恶性转化相关基因的克隆  

Cloning of genes involved in neoplastic transformation induced by high\|LET radiation

作　　者：李刚[1] 吴德昌 胡迎春[1] 赵永良 

机构地区：[1]北京放射医学研究所,100850

出　　处：《中华放射医学与防护杂志》2000年第1期19-24,共6页Chinese Journal of Radiological Medicine and Protection

摘　　要：目的　克隆α粒子辐射致细胞恶性转化相关基因。方法　采用mRNA差异显示技术识别原代大鼠气管上皮细胞同α粒子辐射诱发恶转的大鼠气管上皮细胞之间的差异表达基因。结果　共克隆到 15个可能同α粒子辐射致细胞恶性转化相关的差异表达基因片段 (ESTs) ,共向Gen Bank登录 7条新基因序列。其中克隆ZG 3 5同大鼠AnnexinⅠ基因高度同源 ,AnnexinⅠ作为表皮生长因子受体激酶的底物被认为可能参与细胞增殖信号的转导 ;克隆ZC 5 2同大鼠羧酸酯酶前体物基因高度同源 ;克隆ZA 73为新基因片段 ;克隆ZC 66同肿瘤转移抑制基因nm 2 3高度同源 ,序列分析提示nm 2 3在此恶转细胞中存在突变 ;以克隆ZG 5 2为探针 ,通过筛选cDNA文库 ,克隆到一个长约 3 3 6kb的新基因 ,序列同源性分析提示该基因可能为一个同SR蛋白激酶Ⅱ相关的新型激酶基因 ,其可能的功能为参与前mRNA剪切加工的调控。Northern杂交证实了上述基因片段在恶转的大鼠气管上皮细胞中高表达。结论　上述结果为进一步深入研究辐射致癌、克隆辐射致癌相关基因提供了线索 ,并提示AnnexinⅠ、nm 2 3、羧酸酯酶前体物基因、ZG 5Objective\ To clone genes involved in neoplastic transformation induced by α particles. Methods Differential display technique was used to identify differentially exprssed RNA species between primary and neoplastic transformed rat tracheal epithelial(RTE) cells. Results Fifteen differentially displayed gene fragments were cloned and sequenced.Among them seven novel gene sequences were submitted to GenBank.Homology searching revealed that Clone ZG 35 was highly homologous to rat Annexin Ⅰ gene which has been thought to be involved in mitogenic signal transduction as a substrate of EGF receptor kinase, Clone ZC 52 was nearly identical to a novel rattus norvegicus gene for carboxylestrase precursor, and Clone ZC 66 was highly homologous to rat NDPK gene or metastasis suppressor gene nm23. Sequence analysis suggested that nm23 may be mutated in the transformed RTE cells.and Clone ZA73 was a novel gene fragment.Screening a rat cDNA library using the novel gene Clone ZG52 (Accession number:AF007838) as probe permitted the cloning of a 3.36\|kb gene.Sequence analysis and homology searching indicated that the gene contained a unique 1409\|bp 5'sequence and a 3' sequence showing high homology toward SRPK2,suggesting that it might be a novel SRPK2\|related gene involved in pre\|mRNA splicing.Northern hybridization confirmed that the above gene or gene fragments were up\|regulated in the transformed RTE cells. Conclusion These results provide clues to elucidate the mechanisms of radiation oncogenesis and suggest that Annexin Ⅰ,nm23,and carboxylesterase precursor gene might be involved in the neoplastic transformation induced by α\|partcle radiation.\;

关 键 词：Α粒子 MRNA差异显示 细胞恶性转化 LET辐射 

分 类 号：R818.03[医药卫生—放射医学]