Function of arginine methylation in post-transcriptional gene regulation

精氨酸甲基化在转录后基因调控中的作用

• 批准号: 5441006
• 负责人: Professorin Dr. Antje Ostareck-Lederer
• 金额: --
• 依托单位: Klinik für Operative Intensivmedizin und Intermediate Care
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2005
• 资助国家: 德国
• 起止时间: 2004-12-31 至 2007-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/5441006?language=en
• 关键词: Function; arginine; methylation; post; transcriptional

Arginine methylation affects cellular processes through protein-protein interactions. Its role in the posttranscriptional control of gene expression is ill explored so far. The proposed project will deepen the understanding of the mechanisms by which protein modifications contribute to translational regulation. The focus is on the impact of arginine methylation on the function of the multidomain protein hnRNP K. hnRNP K is a specific regulator of reticulocyte 15-lipoxygenase (r15-LOX) mRNA translation, and an activator and substrate of c-Src kinase. HnRNP K is methylated in vitro and in vivo, but the methyltransferase (PRMT), substrate arginines and functional consequence(s) of the methylation are not known. I identified PRMT1 as the hnRNP K-methylating enzyme in vitro as well as in vivo and showed that endogenous hnRNP K and PRMT1 co-immunoprecipitate. In HeLa cells co-transfected with hnRNP K, c-Src and PRMT1, the hnRNP K/c-Src interaction and hnRNP K tyrosine phosphorylation were strongly reduced. This sup ports my hypothesis that hnRNP K methylation is a functionally important modification. Now I will identify the substrate arginines and generate tools to study whether methylation of hnRNP K affects its function in r15-LOX mRNA translation control and its cellular localization.

精氨酸甲基化通过蛋白质-蛋白质相互作用影响细胞过程。它在基因表达的转录后调控中的作用至今还未得到充分的研究。拟议的项目将加深对蛋白质修饰有助于翻译调控的机制的理解。重点是精氨酸甲基化对多结构域蛋白hnRNP K功能的影响。hnRNP K是网织红细胞15-脂氧合酶（r15-LOX）mRNA翻译的特异性调节剂，也是c-Src激酶的激活剂和底物。HnRNP K在体外和体内被甲基化，但甲基转移酶（PRMT）、底物丝氨酸和甲基化的功能后果尚不清楚。我在体外和体内鉴定了PRMT 1作为hnRNP K-甲基化酶，并表明内源性hnRNP K和PRMT 1共免疫沉淀。在共转染hnRNP K、c-Src和PRMT 1的HeLa细胞中，hnRNP K/c-Src相互作用和hnRNP K酪氨酸磷酸化强烈降低。这支持了我的假设，即hnRNP K甲基化是一个功能上重要的修饰。现在，我将确定的底物丝氨酸和工具，研究是否甲基化的hnRNP K影响其在r15-LOX mRNA的翻译控制和细胞定位的功能。