RNA传感器蛋白催化酶PKR研究新进展

Advances in RNA Sensors Protein Catalytic Enzyme PKR

PKR(Protein Kinase Double-Stranded RNA-Dependent)是丝氨酸-苏氨酸催化酶,细胞浆中重要的RNA传感器(RNA sensor),能自身磷酸化,也可使真核细胞初始化因子2亚单位(subunit of eukaryotic initiation factor 2,e IF-2α)磷酸化。PKR结合病毒dsRNA通过激活PKR/e IF-2α信号通路,抑制病毒基因的翻译,降低病毒蛋白合成,有效减少病毒复制。PKR还可通过激活IκB(inhibitor of NF-κB)/转导核因子(NF-κB,nuclear factorκB)信号通路抑制病毒的转录。PKR与肿瘤的发生具有相关性,能作为治疗癌症的靶点。本文主要综述PKR的分子生物学性质、PKR分子的活化、PKR对IFN转录和转录后的调节、PKR的信号转导、PKR对非病毒病原体感染的调节、PKR对肿瘤细胞的调节等方面的最新进展。

PKR （Protein Kinase Double-Stranded RNA-Dependent） is a serine/threonine catalytic enzyme, an important RNA sensor in cell plasm, that could auto-phosphorylate, also could phosphorylate α-subunit of eukaryotic cells initialization factor 2α （eIF2α）. PKR binding viral dsRNA inhibits translation of viral gene through stimulating signal path to decrease viral protein synthesis, and effectively to reduce viral replication. In addition, PKR could also inhibit viral transcription through stimulating IkB （inhibitor of NF-kB ）/NF-kB （nuclear factor kB ）signal pathway. PKR has reciprocity with genesis of tumor and can be used as a target of cancer therapy. In this paper, we mainly review recent progress on the molecular biology character, the activation, the regulating to IFN＇ s transcription and translation, the signaling pathway, the protection against non-viral pathogen infection and the modulating tumor cells of PKR, and preview the perspectives of PKR studying.