Department of Developmental Medicine, Osaka Medical Center and Research Institute for Maternal and Child Health, Izumi, Osaka 594-1101, Japan.
Biochem Biophys Res Commun. 2010 Feb 26;393(1):111-7. doi: 10.1016/j.bbrc.2010.01.094. Epub 2010 Jan 29.
Transcriptional regulation of human establishment of cohesion 1 homolog 2 (ESCO2), the causative gene of Roberts syndrome, was investigated. Deletion and mutation analyses of the ESCO2 promoter indicated that the selenocysteine tRNA-activating factor (Staf) binding site (SBS) is an essential element for transcriptional activation of ESCO2. Electrophoretic mobility shift assay (EMSA) and chromatin immunoprecipitation (ChIP) assay revealed that the zinc finger protein 143 (ZNF143), a human homolog of Xenopus Staf, bound to the ESCO2 promoter. The ACTACAN submotif, adjacent to SBS, also contributed to transcriptional activation of ESCO2. EMSA indicated that the ACTACAN submotif was not involved in binding of ZNF143 to SBS. S phase-specific expression of the ESCO2 gene was confirmed by real-time reverse transcriptase-polymerase chain reaction (RT-PCR), but EMSA revealed binding of ZNF143 to SBS in G1/S and G2/M phases. These results demonstrated that SBS functioned as the basal transcriptional activator of the S phase-specific gene ESCO2, but other mechanisms are required for cell cycle-dependent expression.
我们研究了人类着丝粒蛋白 E 同源物 2(ESCO2)的转录调控,该基因是罗伯逊易位综合征的致病基因。ESCO2 启动子的缺失和突变分析表明,硒代半胱氨酸 tRNA 激活因子(Staf)结合位点(SBS)是 ESCO2 转录激活的必需元件。电泳迁移率变动分析(EMSA)和染色质免疫沉淀(ChIP)实验表明,锌指蛋白 143(ZNF143),即非洲爪蟾 Staf 的人类同源物,与 ESCO2 启动子结合。紧邻 SBS 的 ACTACAN 亚基也有助于 ESCO2 的转录激活。EMSA 表明,ACTACAN 亚基不参与 ZNF143 与 SBS 的结合。实时逆转录聚合酶链反应(RT-PCR)证实了 ESCO2 基因在 S 期的特异性表达,但 EMSA 显示 ZNF143 在 G1/S 和 G2/M 期与 SBS 结合。这些结果表明,SBS 作为 S 期特异性基因 ESCO2 的基础转录激活子发挥作用,但细胞周期依赖性表达还需要其他机制。