编码新型转录因子样蛋白的小鼠及人类同源cDNA的克隆(英文)

Cloning of a Murine cDNA and Its Human Homolog Encoding Transcription Factor-like Proteins

通过检索GenBank的表达序列标签 (EST)数据库并结合cDNA末端快速扩增法 (RACE) ,从小鼠胸腺克隆到一个新的cDNA序列 ,并从人类肝癌组织中克隆出了其同源cDNA .根据读码框架分析 ,这两个cDNA分别编码 541和 555个氨基酸的蛋白质 两个蛋白质之间氨基酸序列一致率为77% ,和已知蛋白无显著同源性 .分子生物学软件和网上分析表明 ,两个蛋白质所含功能序列与STAT家族成员极为相似 ,均含有包括酪氨酸蛋白激酶在内的多种蛋白激酶的磷酸化位点和核定位信号 (NLS) ,可能是一种新型转录因子 .RT PCR分析显示 ,两个基因在正常组织中选择性表达 ,其分布相似 ,而且都具有一定程度的与分化或增殖相关的趋势 .

By seaching the database of EST (expressd sequence tags) combined with RACE(rapid amplification of cDNA ends),a novel cDNA was cloned from murine thymus, and its human homolog was cloned from hepatocellular carcinoma tissues. Based on the analysis of ORF(open reading frame),the two cDNAs encode proteins of 541 and 555 amino acids respectively. The two proteins have 77% identity on amino acid sequences, they have not significant homologies with all known proteins. Computer analysis revealed that the motifs of the two proteins, especially the nuclear localization signal (NLS) and the phosphorylation sites of several protein kinases including tyrosine protein kinase (TPK), were very like those of STAT family members, suggesting they might be novel transcription factors. RT PCR analysis showed that the two genes were selectively expressed among the normal tissues, and the patterns were very similar. Moreover, they also had a tendancy of relating with cell differentiation or proliferation.