MKP-1 mRNA stabilization and translational control by RNA-Binding proteins HuR and NF90
MKP-1 mRNA stabilization and translational control by RNA-Binding proteins HuR and NF90
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DOI：
10.1128/mcb.00165-08
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发表时间：
2008-07-01
影响因子：
5.3
通讯作者：
Gorospe, Myriam
中科院分区：
文献类型：
--
作者：
Kuwano, Yuki;Kim, Hyeon Ho;Gorospe, Myriam
丝裂原活化蛋白（MAP）激酶磷酸酶1（MKP-1）在去磷酸化并因此使MAP激酶细胞外信号调节激酶（ERK）、c-Jun N-末端激酶（JNK）和p38失活中起主要作用。在这里，我们研究的转录后事件的基础上强大的MKP-1诱导在HeLa细胞中的氧化剂。H2 O2处理有效地稳定了MKP-1 mRNA，并增加了MKP-1 mRNA与翻译机器的关联。发现影响mRNA周转和/或翻译的四种RNA结合蛋白（RNA-BP）（HuR、NF 90、TIAR和TIA-1）与跨越富含MKP-1 AU的3'非翻译区的生物素化转录物结合。通过使用核糖核蛋白免疫沉淀分析，我们发现，过氧化氢处理增加了与HuR和NF 90的MKP-1 mRNA的关联，并降低了其与翻译抑制因子TIAR和TIA-1的关联。HuR或NF 90沉默显著降低了H2 O2刺激的MKP-1 mRNA的稳定性; HuR沉默也显著降低了MKP-1的翻译。反过来，在HuR沉默的培养物中降低MKP-1表达导致H2 O2处理后JNK和p38的磷酸化显著升高。总的来说，氧化应激引起的MKP-1上调受到mRNA稳定性和翻译增加的有力影响，至少部分由RNA-BP HuR和NF 90介导。
The mitogen-activated protein (MAP) kinase phosphatase 1 (MKP-1) plays a major role in dephosphorylating and thereby inactivating the MAP kinases extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK), and p38. Here, we examine the posttranscriptional events underlying the robust MKP-1 induction by oxidants in HeLa cells. H2O2 treatment potently stabilized the MKP-1 mRNA and increased the association of MKP-1 mRNA with the translation machinery. Four RNA-binding proteins (RNA-BPs) that influence mRNA turnover and/or translation (HuR, NF90, TIAR, and TIA-1) were found to bind to biotinylated transcripts spanning the MKP-1 AU-rich 3' untranslated region. By using ribonucleoprotein immunoprecipitation analysis, we showed that H2O2 treatment increased the association of MKP-1 mRNA with HuR and NF90 and decreased its association with the translational repressors TIAR and TIA-1. HuR or NF90 silencing significantly diminished the H2O2-stimulated MKP-1 mRNA stability; HuR silencing also markedly decreased MKP-1 translation. In turn, lowering MKP-1 expression in HuR-silenced cultures resulted in substantially elevated phosphorylation of JNK and p38 after H2O2 treatment. Collectively, MKP-1 upregulation by oxidative stress is potently influenced by increased mRNA stability and translation, mediated at least in part by the RNA-BPs HuR and NF90.