目的： 筛选人卵巢癌差异表达基因2(differentially expressed in ovarian cancer 2, DOC-2)氨基端磷酸酪氨酸作用结构域PID (nDOC 2)的相互作用蛋白质，为研究DOC-2作用的信号通路提供线索。方法： 将含有人DOC-2氨基端PID结构域cDNA的片段插入酵母表达载体pGBKT7中构建诱饵质粒，转化酵母菌AH109并在其内表达，然后转化人胎脑cDNA文库，在营养缺陷培养基和X α 半乳糖苷酶（X-α-gal）上进行双重筛选阳性克隆，PCR扩增出目的片段并测序，进行生物学分析，寻找与DOC-2氨基端PID结构域蛋白相互作用的蛋白质。结果： 经过扩增和筛选胎脑cDNA文库，排除假阳性克隆，得到21个侯选阳性克隆，其中3个克隆进行了序列分析，它们是：Amyloid beta (A4) precursor-like protein 1(APLP1)、TGFβⅢ型受体的部分mRNA和protocadherin gamma subfamily C 3 (PCDHGC3)。结论： 获得的3个基因编码的蛋白可能参与了DOC 2的信号转导通路，为研究DOC-2在卵巢癌基因治疗中的作用提供了新的思路。

Objective: To screen for proteins which can interact with phosphotyrosine-interacting domain (PID) of differentially expressed gene in human ovarian cancer cell line DOC-2 by yeast-two hybrid technique, so as to provide evidence for the signal pathway of DOC-2. Methods: The cDNA sequence of human DOC-2 gene was amplified and its PID domain (nDOC-2) was subcloned into the bait vector pGBKT7 of yeast two-hybrid system; the product was then used to screen an embryo brain cDNA library and the proteins interacting with nDOC-2 were identified. Quadrople dropout(QDO) medium and X-α-gal were used for selecting the positive clones. PCA was used to analyze the amplified sequence. After elimination of the false positive clones, the positive clones were sequenced and analyzed by bioinformatic methods. Results:Twenty-one candidate positive clones were obtained and 3 of them were plasmids encoding Homo sapiens partial mRNA for betaglycan (TBR III gene), Homo sapiens protocadherin gamma subfamily C 3 (PCDHGC3), and APLP1（amyloid beta precursor-like protein 1）.Conclusion: The proteins obtained in this study may play important roles in the signal pathway of DOC-2, which provides a new orientation for DOC-2 gene therapy of ovarian cancers

国家自然科学基金资助项目（No.30500538）