The transcriptional repressor GATAD2B mediates progesterone receptor suppression of myometrial contractile gene expression
The transcriptional repressor GATAD2B mediates progesterone receptor suppression of myometrial contractile gene expression
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DOI：
10.1074/jbc.m117.791350
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发表时间：
2017-07-28
影响因子：
4.8
通讯作者：
Mendelson, Carole R.
中科院分区：
文献类型：
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作者：
Chen, Chien-Cheng;Montalbano, Alina P.;Mendelson, Carole R.
孕激素（P-4）通过孕激素受体（PR）抑制妊娠期间促炎/收缩基因表达的机制尚不完全明确。利用稳定表达野生型PR-A或PR-B （PRWT）的永生化人肌母细胞（hTERT-HM），我们发现P-4显著抑制IL-1对NF-B靶基因COX-2和IL-8的诱导。P-4-PRWT转抑制发生在转录起始水平，并通过减少NF-B p65和RNA聚合酶II对COX-2和IL-8启动子的募集来介导。然而，在稳定表达PR- a或PR- b dna结合域突变体（PRmDBD）的细胞中，p -4介导的转抑制显著减少，表明PR DBD的关键作用。对稳定表达PRWT或PRmDBD的hTERT-HM细胞的ChIP分析显示，P-4处理导致PRWT和PRmDBD对COX-2和IL-8启动子的募集相当，表明PR抑制作用不是通过其直接的DNA结合介导的。通过免疫沉淀法和质谱法，我们鉴定出一种转录抑制因子，GATA锌指结构域2B (GATAD2B)，它与PRWT相互作用强，但与PRmDBD相互作用差。P-4处理PRWT hTERT-HM细胞导致内源性GATAD2B对COX-2和IL-8启动子的募集增强。此外，内源性GATAD2B的siRNA敲低显著降低了P-4-PRWT对COX-2和IL-8的转抑制。值得注意的是，妊娠小鼠和人分娩时子宫肌层中GATAD2B的表达明显降低。我们的研究结果表明，GATAD2B在妊娠期间作为P-4-PR抑制促炎和收缩基因的重要介质。短期内GATAD2B表达减少可能导致PR功能下降，导致分娩。
The mechanisms whereby progesterone (P-4), acting via the progesterone receptor (PR), inhibits proinflammatory/contractile gene expression during pregnancy are incompletely defined. Using immortalized human myometrial (hTERT-HM) cells stably expressing wild-type PR-A or PR-B (PRWT), we found that P-4 significantly inhibited IL-1 induction of the NF-B target genes, COX-2 and IL-8. P-4-PRWT transrepression occurred at the level of transcription initiation and was mediated by decreased recruitment of NF-B p65 and RNA polymerase II to COX-2 and IL-8 promoters. However, in cells stably expressing a PR-A or PR-B DNA-binding domain mutant (PRmDBD), P-4-mediated transrepression was significantly reduced, suggesting a critical role of the PR DBD. ChIP analysis of hTERT-HM cells stably expressing PRWT or PRmDBD revealed that P-4 treatment caused equivalent recruitment of PRWT and PRmDBD to COX-2 and IL-8 promoters, suggesting that PR inhibitory effects were not mediated by its direct DNA binding. Using immunoprecipitation, followed by MS, we identified a transcriptional repressor, GATA zinc finger domain-containing 2B (GATAD2B), that interacted strongly with PRWT but poorly with PRmDBD. P-4 treatment of PRWT hTERT-HM cells caused enhanced recruitment of endogenous GATAD2B to COX-2 and IL-8 promoters. Further, siRNA knockdown of endogenous GATAD2B significantly reduced P-4-PRWT transrepression of COX-2 and IL-8. Notably, GATAD2B expression was significantly decreased in pregnant mouse and human myometrium during labor. Our findings suggest that GATAD2B serves as an important mediator of P-4-PR suppression of proinflammatory and contractile genes during pregnancy. Decreased GATAD2B expression near term may contribute to the decline in PR function, leading to labor.