The transcription factor Sp3 regulates the expression of a metastasis-related marker of sarcoma, actin filament-associated protein 1-like 1 (AFAP1L1).
The transcription factor Sp3 regulates the expression of a metastasis-related marker of sarcoma, actin filament-associated protein 1-like 1 (AFAP1L1).
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DOI：
10.1371/journal.pone.0049709
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发表时间：
2013
期刊：
影响因子：
3.7
通讯作者：
Toguchida J
中科院分区：
文献类型：
--
作者：
Kajita Y;Kato T Jr;Tamaki S;Furu M;Takahashi R;Nagayama S;Aoyama T;Nishiyama H;Nakamura E;Katagiri T;Nakamura Y;Ogawa O;Toguchida J
我们先前从65例梭形细胞肉瘤的基因表达谱中确定了肌动蛋白毒力相关蛋白1样1（AFAP 1 L1）作为转移预测标记物，并在多变量分析中证明AFAP 1 L1表达上调是远处转移的独立危险因素。然而，关于AFAP 1 L1的表达是如何被调节的知之甚少。荧光素酶报告基因分析表明，位于转录起始位点-85到75的特异性蛋白（Sp）的串联结合基序对启动子活性至关重要。Sp1和Sp3蛋白的过表达反式激活近端AFAP 1 L1启动子构建体，并且电泳迁移率变动分析表明，Sp1和Sp3都能够在体外结合到该区域。然而，染色质免疫沉淀实验显示，Sp3是AFAP 1 L1阳性细胞中AFAP 1 L1基因近端启动子区结合的主要因子。光神霉素A（一种与富含GC区域结合的蛋白质抑制剂）处理可以阻止Sp3与AFAP 1 L1近端启动子区域结合，并以剂量依赖性方式降低其表达。最后，使用小抑制RNA双链体（siRNA）敲低Sp3显著降低了AFAP 1 L1的表达，其通过表达siRNA抗性Sp3而部分恢复。这些发现表明Sp3在肉瘤中作为转移相关基因AFAP 1 L1表达的驱动者的新作用。
We previously identified actin filament-associated protein 1-like 1 (AFAP1L1) as a metastasis-predicting marker from the gene-expression profiles of 65 spindle cell sarcomas, and demonstrated the up-regulation of AFAP1L1 expression to be an independent risk factor for distant metastasis in multivariate analyses. Little is known, however, about how the expression of AFAP1L1 is regulated. Luciferase reporter assays showed tandem binding motives of a specificity protein (Sp) located at −85 to −75 relative to the transcriptional start site to be essential to the promoter activity. Overexpression of Sp1 and Sp3 proteins transactivated the proximal AFAP1L1 promoter construct, and electrophoretic mobility shift assays showed that both Sp1 and Sp3 were able to bind to this region in vitro. Chromatin immunoprecipitation experiments, however, revealed that Sp3 is the major factor binding to the proximal promoter region of the AFAP1L1 gene in AFAP1L1- positive cells. Treatment with mithramycin A, an inhibitor of proteins binding to GC-rich regions, prevented Sp3 from binding to the proximal promoter region of AFAP1L1 and decreased its expression in a dose-dependent manner. Finally, knocking down Sp3 using small inhibitory RNA duplex (siRNA) reduced AFAP1L1 expression significantly, which was partially restored by expressing siRNA-resistant Sp3. These findings indicate a novel role for Sp3 in sarcomas as a driver for expression of the metastasis-related gene AFAP1L1.
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影响因子：
3.7
作者：
Essafi-Benkhadir, Khadija;Grosso, Sebastien;Puissant, Alexandre;Robert, Guillaume;Essafi, Makram;Deckert, Marcel;Chamorey, Emmanuel;Dassonville, Olivier;Milano, Gerard;Auberger, Patrick;Pages, Gilles
通讯作者：
Pages, Gilles
影响因子：
9.7
作者：
Kawai, A;Naito, N;Beppu, Y
通讯作者：
Beppu, Y
影响因子：
5.3
作者：
FLYNN, DC;LEU, TH;PARSONS, JT
通讯作者：
PARSONS, JT
影响因子：
8
作者：
Shirasaki, F;Makhluf, HA;Trojanowska, M
通讯作者：
Trojanowska, M
影响因子：
4.8
作者：
Sapetschnig, A;Koch, F;Suske, G
通讯作者：
Suske, G