2017年4月4日 · Short elements in mammalian mRNA can control gene expression by activating the RNA-dependent protein kinase PKR that attenuates translation by phosphorylating cytoplasmic eukaryotic initiation...

2005年9月23日 · The antiviral RNA-dependent protein kinase, PKR, binds to viral double-stranded RNA in the cell and halts protein synthesis by phosphorylating the α subunit of the translation initiation factor eIF2. In this issue of Cell, two complementary papers Dar et al. (2005) and Dey et al. (2005) address the interaction between PKR and eIF2α.

TC是一种异源三聚体，是由真核翻译起始因子eIF2（α、β和γ亚基组成）、GTP和带电荷甲硫酰基-起始转运RNA（Met-tRNAi）组成。 TC参与到AUG起始的转录组中开放阅读框的翻译过程。 AUG起始密码子识别导致GTP水解，将Met-tRNAi释放到核糖体的P位，之后eIF2-GDP解离，核糖体组装，蛋白质翻译进入延伸阶段。 eIF2结合的GDP交换成GTP会使eIF2重新进入活性状态。 GDP交换为GTP的步骤限制了TC的形成，也成为了AUG起始的mRNA翻译的限速步骤。 TC …

eIF2 起始复合体整合了各种各样应激相关的信号来调控全局和特异性 mRNA 翻译。 在适宜的条件下，eIF2 会结合 GTP 和 Met-tRNAi 形成三元复合体 (TC)，三元复合体随后结合 40S 核糖体亚基、eIF1、eIF1A、eIF5 和 eIF3，形成 43S 起始前复合体 (PIC)。

2020年6月8日 · EIF2AK2, commonly known as protein kinase R (PKR), is activated by viruses and alcohol 11, 12. EIF2AK3, commonly known as protein kinase R-like endoplasmic reticulum (ER) kinase (PERK), is...

2005年9月23日 · The structures of eIF2alpha bound to PKR reveal that PKR forms a dimer, the interface of which is essential for kinase activation, and demonstrate how this protein substrate docks to its kinase. The structures, coupled with mutagenesis analysis, also demonstrate how phosphorylation of the activation loop can allosterically couple two distal ...

In this study, we investigated whether PKR protein expression is correlated with mRNA levels and also evaluated molecular biomarkers that are associated with PKR, such as phosphorylated PKR (p-PKR) and phosphorylated eIF2α (p-eIF2α).

2005年9月23日 · The antiviral protein kinase PKR inhibits protein synthesis by phosphorylating the translation initiation factor eIF2α on Ser51. Binding of double-stranded RNA to the regulatory domains of PKR promotes dimerization, autophosphorylation, and …

2005年9月23日 · Comparing the phenotypes of pkr −/− and PKR-T487D knockin cells may help reveal roles for PKR that are independent of eIF2α phosphorylation. As all four eIF2α kinases dimerize and autophosphorylate on a conserved Thr in the kinase activation segment, we propose that the PKR activation mechanism delineated in this manuscript linking kinase ...

Short elements in mammalian mRNA can control gene expression by activating the RNA-dependent protein kinase PKR that attenuates translation by phosphorylating cytoplasmic eukaryotic initiation factor 2α (eIF2α). We demonstrate a novel, positive role for PKR activation and eIF2α phosphorylation in hu …