Hypoxia-inducible factor 1α is essential for cell cycle arrest during hypoxia
Hypoxia-inducible factor 1α is essential for cell cycle arrest during hypoxia
复制标题
DOI：
10.1128/mcb.23.1.359-369.2003
复制
发表时间：
2003-01-01
影响因子：
5.3
通讯作者：
Johnson, RS
中科院分区：
文献类型：
--
作者：
Goda, N;Ryan, HE;Johnson, RS
典型的细胞对缺氧的反应是停止生长。缺氧诱导的生长停滞在不同的细胞类型中不同，但可能是对创伤和损伤的反应的一个重要方面。缺氧反应的一个重要组成部分是缺氧诱导因子I（HIF-1）转录因子的激活。尽管这种转录因子对于适应低氧水平是必不可少的，但它影响细胞周期停滞的机制，包括它与肿瘤抑制蛋白p53合作的程度，仍然知之甚少。为了确定HIF-1在原代细胞生长停滞中功能的广泛相关方面，我们检测了两种不同的原代分化细胞类型，它们含有HIF-1的氧敏感组分（HIF-1 α基因产物）的可删除等位基因。这两种细胞类型是鼠胚胎成纤维细胞和脾B淋巴细胞;为了确定HIF-1 α的功能如何影响p53，我们还创建了双敲除（HIF-1 α无效，p53无效）菌株和细胞。在这两种细胞类型中，HIF-1 α的缺失消除了缺氧诱导的生长停滞，并以p53非依赖性方式完成。令人惊讶的是，在所有情况下，缺乏p53和HIF-1 alpha基因的细胞都完全失去了响应缺氧而改变细胞周期的能力。此外，我们发现HIF-1 α的缺失导致缺氧时S期进展加快，而不是生长停滞。我们表明，缺氧会导致细胞周期蛋白依赖性激酶抑制剂p21和p27的表达呈HIF-1 α依赖性增加;我们还发现缺氧中视网膜母细胞瘤蛋白的低磷酸化是HIF-1 α依赖性的。这些数据表明，转录因子HIF-1是缺氧期间原代细胞中细胞周期停滞的主要调节因子。
A classical cellular response to hypoxia is a cessation of growth. Hypoxia-induced growth arrest differs in different cell types but is likely an essential aspect of the response to wounding and injury. An important component of the hypoxic response is the activation of the hypoxia-inducible factor I (HIF-1) transcription factor. Although this transcription factor is essential for adaptation to low oxygen levels, the mechanisms through which it influences cell cycle arrest, including the degree to which it cooperates with the tumor suppressor protein p53, remain poorly understood. To determine broadly relevant aspects of HIF-1 function in primary cell growth arrest, we examined two different primary differentiated cell types which contained a deletable allele of the oxygen-sensitive component of HIF-1, the HIF-1alpha gene product. The two cell types were murine embryonic fibroblasts and splenic B lymphocytes; to determine how the function of HIF-1alpha influenced p53, we also created double-knockout (HIF-1alpha null, p53 null) strains and cells. In both cell types, loss of HIF-1alpha abolished hypoxia-induced growth arrest and did this in a p53-independent fashion. Surprisingly, in all cases, cells lacking both p53 and HIF-1alpha genes have completely lost the ability to alter the cell cycle in response to hypoxia. In addition, we have found that the loss of HIF-1alpha causes an increased progression into S phase during hypoxia, rather than a growth arrest. We show that hypoxia causes a HIF-1alpha-dependent increase in the expression of the cyclin-dependent kinase inhibitors p21 and p27; we also find that hypophosphorylation of retinoblastoma protein in hypoxia is HIF-1alpha dependent. These data demonstrate that the transcription factor HIF-1 is a major regulator of cell cycle arrest in primary cells during hypoxia.