ETS-1 transcription factor binds cooperatively to the palindromic head to head ETS-binding sites of the stromelysin-1 promoter by counteracting autoinhibition
ETS-1 transcription factor binds cooperatively to the palindromic head to head ETS-binding sites of the stromelysin-1 promoter by counteracting autoinhibition
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DOI：
10.1074/jbc.m200088200
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发表时间：
2002-08-16
影响因子：
4.8
通讯作者：
Aumercier, M
中科院分区：
文献类型：
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作者：
Baillat, D;Bègue, A;Aumercier, M
基质溶素-1（基质金属蛋白酶-3）是基质金属蛋白酶家族的成员。其基因表达的调节对于组织稳态是至关重要的。在病理过程中观察到基质分解素-1和ETS-1基因共表达增加的模式。基质分解素-1启动子通过两个回文头对头ETS结合位点被ETS蛋白反式激活，这是金属蛋白酶启动子中不常见的构型。通过使用表面等离子体共振、电泳迁移率变动分析和光交联，我们发现全长人ETS-1（p51）协同结合人基质分解素-1启动子的ETS结合位点回文，促进第二个ETS-1分子的结合，形成ETS-1.DNA.ETS-1三元复合物。对N-末端缺失突变体的研究使我们得出结论，合作结合意味着自抑制抵消作用，需要由基因的外显子VII编码的蛋白质的245-330个残基区域。该区域在ETS-1的天然p42同种型中缺失，其不能与回文序列协同结合。瞬时转染实验表明DNA结合与p51启动子反式激活之间存在良好的相关性。相比之下，p42表现出较差的反式激活，加强了合作结合的意义，充分的反式激活。这是ETS-1首次被证明能够抵消自身的自抑制作用。
Stromelysin-1 (matrix metalloproteinase-3) is a member of the matrix metalloproteinase family. Regulation of its gene expression is critical for tissue homeostasis. Patterns of increased co-expression of stromelysin-1 and ETS-1 genes have been observed in pathological processes. Stromelysin-1 promoter is transactivated by ETS proteins through two palindromic head to head ETS-binding sites, an unusual configuration among metalloproteinase promoters. By using surface plasmon resonance, electrophoretic mobility shift assay, and photo-cross-linking, we showed that full-length human ETS-1 (p51) binds cooperatively to the ETS-binding site palindrome of the human stromelysin-1 promoter, with facilitated binding of the second ETS-1 molecule to form an ETS-1.DNA.ETS-1 ternary complex. The study of N-terminal deletion mutants allowed us to conclude that cooperative binding implied autoinhibition counteraction, requiring the 245-330-residue region of the protein that is encoded by exon VII of the gene. This region was deleted in the natural p42 isoform of ETS-1, which was unable to bind cooperatively to the palindrome. Transient transfection experiments showed a good correlation between DNA binding and promoter transactivation for p51. In contrast, p42 showed a poorer transactivation, reinforcing the significance of cooperative binding for full transactivation. It is the first time that ETS-1 was shown to be able to counteract its own autoinhibition.