PHD1 interacts with ATF4 and negatively regulates its transcriptional activity without prolyl hydroxylation
PHD1 interacts with ATF4 and negatively regulates its transcriptional activity without prolyl hydroxylation
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DOI：
10.1016/j.yexcr.2011.09.005
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发表时间：
2011-12-10
影响因子：
3.7
通讯作者：
Yasumoto, Ken-ichi
中科院分区：
文献类型：
--
作者：
Hiwatashi, Yusuke;Kanno, Kohei;Yasumoto, Ken-ichi
细胞对缺氧的反应在循环系统和肺部疾病以及癌症中起着重要作用。缺氧诱导因子（Hypoxia-inducible factors，HIF）是调节机体缺氧反应的主要转录因子。HIF的α-亚基被脯氨酰-4-羟化酶结构域（PHD）家族成员PHD 1、PHD 2和PHD 3以氧依赖性方式羟基化。在这里，我们报告的鉴定ATF 4作为一种蛋白质与PHD 1以及PHD 3，但不与PHD 2相互作用。ATF 4的中心区域包括Zipper II结构域、ODD结构域和β-TrCP识别基序，它们参与了与PHD 1的相互作用。PHD 1的共存稳定了ATF 4，而PHD 3则使ATF 4不稳定。此外，ATF 4的共表达使PHD 3不稳定，而PHD 1的稳定性不受ATF 4的存在的影响。在ATF 4中脯氨酸残基的丙氨酸突变，满足由PHDs的羟基化共识不影响ATF 4与PHD 1和PHD 3的结合活性。此外，体外脯氨酰羟基化测定清楚地表明，ATF 4不作为PHD 1和PHD 3的底物。PHD 1或PHD 3与ATF 4的共表达抑制了ATF 4的转录活性。这些结果表明，PHD 1和PHD 3控制ATF 4的反式激活活性。(C)2011 Elsevier Inc. All rights reserved.
Cellular response to hypoxia plays an important role in both circulatory and pulmonary diseases and cancer. Hypoxia-inducible factors (HIFs) are major transcription factors regulating the response to hypoxia. The alpha-subunits of HIFs are hydroxylated by members of the prolyl-4-hydroxylase domain (PHD) family, PHD1, PHD2, and PHD3, in an oxygen-dependent manner. Here, we report on the identification of ATF4 as a protein interacting with PHD1 as well as PHD3, but not with PHD2. The central region of ATF4 including the Zipper II domain, ODD domain and beta-TrCP recognition motif were involved in the interaction with PHD1. Coexistence of PHD1 stabilized ATF4, as opposed to the destabilization of ATF4 by PHD3. Moreover, coexpression of ATF4 destabilized PHD3, whereas PHD1 stability was not affected by the presence of ATF4. Mutations to alanine of praline residues in ATF4 that satisfied hydroxylation consensus by PHDs did not affect binding activity of ATF4 to PHD1 and PHD3. Furthermore, in vitro prolyl hydroxylation assay clearly indicated that ATF4 did not serve as a substrate of both PHD1 and PHD3. Coexpression of PHD1 or PHD3 with ATF4 repressed the transcriptional activity of ATF4. These results suggest that PHD1 and PHD3 control the transactivation activity of ATF4. (C) 2011 Elsevier Inc. All rights reserved.