Yasinska Inna M, Sumbayev Vadim V
Department of Biochemistry, Mechnikov Odessa National University, Apt 208, Glushko prospect 16, Odessa 65104, Ukraine.
FEBS Lett. 2003 Aug 14;549(1-3):105-9. doi: 10.1016/s0014-5793(03)00807-x.
Hypoxia inducible factor 1 (HIF-1) is a heterodimeric transcriptional complex that plays pivotal role in the regulation of cellular utilization of oxygen as well as glucose and is an essential regulator of angiogenesis in solid tumor and ischemic disorders. Recently HIF-1alpha, a subunit of HIF-1 complex, was characterized as a potential target for S-nitrosation, providing no information about the impact of this posttranslational modification on the protein transactivation. Cys-800 of HIF-1alpha protein has reactive SH-group, which is critical for the recruitment of p300 co-activator that is necessary for transcriptional activity of HIF-1 complex. Here we report that S-nitrosation of Cys-800 activates HIF-1alpha-p300 interaction and stimulates protein transactivation. We have found that S-nitrosation of the HIF-1alpha C-terminal domain by nitric oxide derived from donors and nitric oxide synthase increases protein transcriptional activity. The increase of HIF-1 transcriptional activity was not observed in the case of Cys-800 substitution to Ala, though other protein thiol groups were nitrosated. Experiments with GST pull-down assay suggest that S-nitrosation of Cys-800 stimulates the recruitment of p300 co-activator protein to the HIF-1alpha C-terminal domain.
缺氧诱导因子1（HIF-1）是一种异二聚体转录复合物，在细胞对氧气以及葡萄糖的利用调节中起关键作用，并且是实体瘤和缺血性疾病中血管生成的重要调节因子。最近，HIF-1复合物的一个亚基HIF-1α被鉴定为S-亚硝基化的潜在靶点，但未提供有关这种翻译后修饰对蛋白质反式激活影响的信息。HIF-1α蛋白的半胱氨酸800具有反应性巯基，这对于募集p300共激活因子至关重要，而p300共激活因子是HIF-1复合物转录活性所必需的。在此我们报告，半胱氨酸800的S-亚硝基化激活HIF-1α-p300相互作用并刺激蛋白质反式激活。我们发现，来自供体的一氧化氮和一氧化氮合酶产生的一氧化氮对HIF-1α C末端结构域进行S-亚硝基化会增加蛋白质的转录活性。在将半胱氨酸800替换为丙氨酸的情况下，未观察到HIF-1转录活性增加，尽管其他蛋白质巯基被亚硝基化了。GST下拉试验表明，半胱氨酸800的S-亚硝基化刺激p300共激活因子蛋白募集到HIF-1α C末端结构域。
