Study on hypoxia-inducible factor and its regulatory factor

缺氧是肿瘤发生的关键因素。缺氧诱导低氧诱导因子（Hypoxia inducible factor， HIF）的表达，HIF是低氧应答基因的转录因子。HIF是由HIF-α和HIF-β组成的异二聚体蛋白。α亚基（HIF-2α）是HIF表达的限制因子，因为HIF-2α在缺氧条件下稳定表达，而在常氧条件下不稳定表达。在本研究中，我们证实了在正常缺氧条件下，klhl20可增强HIF-2α的表达，而HIF-2α可下调雌激素受体α的表达。在此基础上，我们构建了一个基于细胞的低氧反应生物测定系统，并测定了食品成分的抗缺氧活性。

Hypoxia is a key factor in tumorigenesis. Hypoxia induces theexpression of hypoxia-inducible factor (HIF), which is a transcriptional factor forhypoxia-responsive genes. HIF is a heterodimeric protein composed of HIF-α and HIF-β.The α subunit (HIF-2α) is limiting factor for HIF expression because HIF-2α is stablyexpressed in hypoxia, but not in normoxia. In the present study, we demonstrate thatKLHL20 enhances the expression of HIF-2α and that HIF-2α down-regulates theexpression of estrogen receptor α in normoxia. Based on these results, we constructed acell-based bioassay system for hypoxic response and determined anti-hypoxic activity offood components.