Protein kinase R

Zhou, H. R., Lau A.S., and Pestka J.J. Role of double-stranded RNA-activated protein kinase R (PKR) in deoxynivalenol-induced ribotoxic stress response. Toxicol. Sci. 74, 335, 2003. 

Auch CJ, Saha RN, Sheikh FG, Liu X, Jacobs BL, Pahan K (2004) Role of protein kinase R in double-stranded RNA-induced expression of nitric oxide synthase in human astroglia. FEBS Lett 563 223—228. 

Type I (IFN-a/P) and type II (IFN-y) IFNs are major lines of defense against viral infection. IFNs mediate direct antiviral effector mechanisms that inhibit multiple steps of viral replication (Samuel 1991 Vilcek and Sen 1996). For example, 2, 5 -oligoadenylate synthetase (2, 5 -OAS) activates ribonuclease L, which degrades mRNA and limits the accumulation of viral transcripts. Protein kinase R blocks translation of viral transcripts by phosphorylating translation initiation factor eIF-2. Mx proteins block influenza, vesicular stomatitis virus, and herpes simplex virus replication by an unknown mechanism. 

Cassady KA, Gross M, Roizman B (1998a) The herpes simplex virus US 11 protein effectively compensates for the gamma 1(34.5) gene if present before activation of protein kinase R by precluding its phosphorylation and that of the alpha subunit of eukaryotic translation initiation factor 2. J Virol... 

Fig. 3.3 Flow charts of differential NO stress leading to inhibition of protein synthesis and cytosta-sis in human breast cancer cells. HRI, heme-regulated inhibitor PKR, protein kinase R. Adapted from Pervin et al. (2008a) with permission from the publisher...

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