胃癌相关基因gcI的克隆及其功能预测

Cloning of Gastric Cancer Related Gene gcI and Prediction of Its Functions

目的:应用生物信息学平台对胃癌相关基因表达片段进行cDNA全长克隆及序列分析和蛋白功能预测。方法:选用人胃癌、癌前病变及正常胃粘膜组织经mRNA差异显示技术筛选获得的差异表达片段,对所获得的1条功能未知基因表达片段“I”,利用5'cDNA末端快速扩增方法扩增全长cDNA,结合Northern杂交印迹方法进行验证分析;利用NCBI、EMBL数据库资源分析其编码氨基酸的生物学特征以及预测其编码蛋白的功能。结果:扩增得到序列I的全长cDNA,命名为gcI。分析显示gcI含有2个跨膜区,定位于胞膜;含有3个蛋白激酶C磷酸化位点和3个N端豆蔻酰化作用位点。结论:克隆的胃癌相关基因表达全长序列gcI、编码与信号转导有关的跨膜蛋白,可能是参与胃癌发生过程中的相关基因。

Objective： To clone the full length of gastric cancer related gene expressed segment, analyze its biological characters and to predict protein function with bioinformatics. Methods： Differentially expressed cDNA fragments were obtained through fluorescent differential display PCR in gastric cancer and its pre-malignant lesions and normal gastric mucosa tissues. Cloned full length cDNA of the sequence I which no homologous sequences in databases with 5＇RACE, and identified the reality of sequences using Northern blot method. The databases of NCBI and EMBL was used to analyze its biological characters of the coded amino acid ORF and to predict the function of encoded polypeptide. Resuits： The full-length cDNA of seqence I was obtained using 5＇RACE method. The ORF sequence was named as gcI, with two trans-membrane sections. Results of function sites searched by PROSITE revealed that gcI had three protein kinase C phosphorylation sites and three N-myristoylation sites. Conclusion： gcI, a novel gastric cancer related gene encoding a trans-menbrane protein related to signal transduction, might be a putative gene concerned with gastric cancer genesis.