【摘要】 以大鼠增强子结合蛋白（Ｃ／ＥＢＰ）ｃＤＮＡ为探针，筛选人胎肝ｃＤＮＡ文库，得到一个含有２４８０碱基命名为ＨＰ８的ｃＤＮＡ克隆，其中８４～１１０９位碱基属编码区，经基因数据库（ＥＭＢＬ，９５．６版本）查对未发现同源基因。该基因编码的蛋白Ｃ－末端含有亮氨酸拉链结构（ｌｅｕｃｉｎｅｚｉｐｐｅｒｓｔｒｕｃｔｕｒｅ），和Ｃ／ＥＢＰ功能区（Ｃ－末端６０个氨基酸）同源性高达９７％，而上游编码区则与Ｃ／ＥＢＰ及其已知家族同源性很低，表明该基因属Ｃ／ＥＢＰ基因家族新成员。基因组Ｓｏｕｔｈｅｒｎ杂交证实该基因为单拷贝基因，在１４种胎儿组织中显示小肠、皮肤高表达，肾上腺中度表达，肝、肺、肾、甲状腺、胆囊低表达。在５例正常成人肝组织中仅２例低表达，而在１３对肝癌及癌旁肝组织中显示９例癌组织及７例癌旁组织高表达。以上结果提示该基因可能与细胞增殖有关。它的详尽功能的研究正在进行中。更多还原

【Abstract】 We have obtained one positive clone by screening human fetal liver cDNA library with rat C/EBPcDNA probe.This clone HP8 contained 2480 base pairs which includes 1026 coding base pairs(From No·84to 1109).The checking showed this DNA sequence is not included in the Gene Database (EMBL 95.6)#.The 341 amino acids encoded by this gene had the leucine zipper structure and demonstrated the highest ho-mology (97%)with C/EBP throughout the DNA-binding domain and leucine repeat region (C-terminal 60amino acids).Beyond this region,only low homology was detected in HP8 protein and C/EBP or C/EBP re-lated proteins. Herewith,HP8 was defined as a novel member of C/EBP gene family. Genomic Southern blotanalysis confirmed that HP8 was a single copy gene. Northern blot analysis in 14 different fetus tissuesshowed that HP8 mRNA was expressed in small intestine and skin at a high level,in adrenal is middle level,and in liver,lung,kidney,thyroid gland and gallbladder a low level. In 5 human adult liver tissues,only twocases were found low level HP8 mRNA expression,whereas in 13 hepatomas and its surrounding nontumor-ous hepatic tissues,high level HP8 mRNA expression was detected in 9 hepatomas and 7 surrounding nontu-morous hepatic tissues。These results suggested that the HP8 gene might be a transactivator related to cellgrowth.The research of its detail function is now in progress.更多还原