Phosphorylation of Estrogen Receptor α at Serine 118 Directs Recruitment of Promoter Complexes and Gene-Specific Transcription
Phosphorylation of Estrogen Receptor α at Serine 118 Directs Recruitment of Promoter Complexes and Gene-Specific Transcription
复制标题
DOI：
10.1210/en.2010-1281
复制
发表时间：
2011-06-01
期刊：
影响因子：
4.8
通讯作者：
Rowan, Brian G.
中科院分区：
文献类型：
--
作者：
Duplessis, Tamika T.;Williams, Christopher C.;Rowan, Brian G.
雌激素受体α（ER α）的磷酸化对于受体功能很重要，尽管特定ER α磷酸化位点在ER α介导的转录中的作用仍有待充分评估。ER α的转录激活涉及与启动子增强子元件处的辅调节因子的动态协调相互作用以影响基因表达。为了确定ER α磷酸化是否影响基因特异性启动子处独特蛋白复合物的募集，评估了ER α Ser 118磷酸化的变化对受体和辅调节因子募集以及ER α调节基因转录的影响。染色质免疫沉淀试验，以衡量启动子协会发现17 β-雌二醇（E2）依赖性招聘的ER α在150分钟的ER α调节的启动子，而ER α在Ser 118磷酸化后，E2处理的启动子解离。与野生型（WT）-ER α转染相比，Ser 118突变为丙氨酸（S118 A）改变了ER α和p160辅助调节因子与E靶启动子的非配体和配体诱导的关联。S118 A和WT-ER α对雌激素反应元件驱动的pS2启动子表现出相似的募集水平，并在E2处理后诱导pS2 mRNA。尽管E2处理后WT-ER α被募集到c-myc和cyclin D1启动子并诱导mRNA表达，但S118 A与c-myc和cyclin D1启动子的相互作用降低，E2不诱导c-myc和cyclin D1 mRNA表达。此外，S118 A导致类固醇受体辅激活因子-1、糖皮质激素受体相互作用蛋白-1的募集增加，并且在乳腺癌-1中激活为pS2、c-myc和细胞周期蛋白D1，而与E2的存在无关。总之，这些数据表明ER α的位点特异性磷酸化指导ER α和转录辅助调节因子的基因特异性募集至ER α靶基因启动子。（内分泌学152：2517-2526，2011）
Phosphorylation of estrogen receptor alpha (ER alpha) is important for receptor function, although the role of specific ER alpha phosphorylation sites in ER alpha-mediated transcription remains to be fully evaluated. Transcriptional activation by ER alpha involves dynamic, coordinate interactions with coregulators at promoter enhancer elements to effect gene expression. To determine whether ER alpha phosphorylation affects recruitment of unique protein complexes at gene-specific promoters, changes in ER alpha Ser118 phosphorylation were assessed for effects on receptor and coregulator recruitment and transcription of ER alpha-regulated genes. Chromatin immunoprecipitation assays to measure promoter association found a 17 beta-estradiol (E2)-dependent recruitment of ER alpha at 150 min to ER alpha-regulated promoters, whereas ER alpha phosphorylated at Ser118 was dissociated from promoters after E2 treatment. Mutation of Ser118 to alanine (S118A) altered unliganded and ligand-induced association of ER alpha and p160 coregulators with E target promoters when compared with wild-type (WT)-ER alpha transfection. S118A and WT-ER alpha exhibited a similar level of recruitment to the estrogen response element-driven pS2 promoter and induced pS2 mRNA after E2 treatment. Although WT-ER alpha was recruited to c-myc and cyclin D1 promoters after E2 treatment and induced mRNA expression, S118A exhibited reduced interaction with c-myc and cyclin D1 promoters, and E2 did not induce c-myc and cyclin D1 mRNA. In addition, S118A resulted in increased recruitment of steroid receptor coactivator-1, glucocorticoid receptor interacting protein-1, and activated in breast cancer-1 to pS2, c-myc, and cyclin D1 irrespective of the presence of E2. Together, these data indicate that site specific phosphorylation of ER alpha directs gene-specific recruitment of ER alpha and transcriptional coregulators to ER alpha target gene promoters. (Endocrinology 152: 2517-2526, 2011)