hTRIP15对甲状腺激素受体功能的影响

Effect of Human Thyroid Receptor Interacting Protein 15 on the Function of Thyroid Receptor

目的确立人甲状腺激素受体相互作用蛋白15(hTRIP15)对甲状腺激素受体(TR)功能的影响。方法应用融合蛋白、蛋白体外翻译及谷胱苷肽S转移酶“拉下”(GSTpulldown)试验研究蛋白—蛋白的相互作用,凝胶阻滞(gelshift)试验检测蛋白-DNA的结合活性。结果经大肠杆菌表达hTRIP15融合蛋白或体外翻译TRα所显示的分子量与预测大小相吻合。hTRIP15及hTRIP15N末端均可与TRα相互作用;hTRIP15抑制TR与TR反应元件(TRE)结合,且增加hTRIP15剂量时更明显。结论提示hTRIP15作为共抑制因子调节TR对靶基因的转录,hTRIP15N端是TR结合功能域,而C端可能为调节功能域。

Objective To identify the effects of human thyroid receptor interacting protein 15 (hTRIP 15) on the function of thyroid receptor (TR). Methods Fusion protein, protein translation in vitro and glutathione -S- transferase (GST) pulldown assay were used for identification of protein-protein interaction, and gel-shift assay for protein-DNA interaction. Results Molecular weight of hTRIP 15 fusion proteins expressed in E coli and TRα translated in vitro matched with that predicted. hTRIP 15 and its N terminal could interact with TRα. hTRIP15 inhibited binding of TR and thyroid response element (TRE), with more significant inhibition using high dose of hTRIP 15. Conclusion hTRIP 15 regulates transcription of the target genes of TR as a corepressor. TR-binding domain is in hTRIP15 N terminal,and the C terminal may be the regulatory domain.