EXCEED THE SPACE PROVIDED. The OVERALL OBJECTIVE of the proposed investigation is to elucidate the role of the interferon- inducible double-stranded RNA-dependent protein kinase (PKR) in the actions which natural and recombinant interferons mediate on viral and host functions.
The SPECIFIC AIMS of our proposed continuation investigation of protein phosphorylation and interferon (IFN) action are as follows: (1). To further delineate the structure of the Y-flanking region of the Pkr gene required for interferon- inducible as well as basal transcriptional activity. To map the major Pkr transcription sites, using RNA from tissues of uninfected and infected mice and from untreated and IFN-treated cells. To elucidate the importance of potential protein binding sites in Pkr promoter activity, with emphasis placed on proteins binding the novel 15 nucleotide DNA element designated KCS which so far is unique to the human and mouse Pkr promoters. To examine the ability of cytokines and factors other than IFNs to modulate Pkr expression. (2). To further characterize the biochemical and biophysical properties of the PKR kinase. To attempt to identify definitively the sites ofPKR autophosphorylation associated with activation. To characterize the functional selectivity of dsRNA binding domains and RNA effectors through the study of chimeric proteins, synthetic aptamer RNAs, and naturally occurring RNAs (reovirus sl RNA, adenovirus VA RNA). To characterize the structural basis and functional significance of PKR protein interactions, and to continue efforts to obtain a crystal structure of PKR with the hope that the structure will provide further insight into function. (3). To characterize the expression and function ofwildtype and mutant PKR proteins in cell culture. To assess the effect of singular expression of PKR forms in transfected PKR-deficient cells. To use RNase protection and DNA microarray approaches to gain insights into role of PKR on transcript profiles in untreated, IFN-treated, and infected cells from two strains of mice. The health relatedness of the proposed research stems from the likelihood that the work may contribute to a better understanding of regulatory mechanisms operative in normal cells as well as virus-infected cells. Elucidation of the actions of IFN at the molecular level is of immediate importance in view of the use of IFN in the clinic. PERFORMANCE SiTE ========================================Section End===========================================

National Institute of Health (NIH)
National Institute of Allergy and Infectious Diseases (NIAID)
Research Project (R01)
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Virology Study Section (VR)
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Goodrich, Adrienne J
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University of California Santa Barbara
Schools of Arts and Sciences
Santa Barbara
United States
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Ma, Dzwokai; George, Cyril X; Nomburg, Jason et al. (2017) Upon Infection the Cellular WD Repeat-containing Protein 5 (WDR5) Localizes to Cytoplasmic Inclusion Bodies and Enhances Measles Virus Replication. J Virol :
Kainulainen, Markus; Lau, Simone; Samuel, Charles E et al. (2016) NSs Virulence Factor of Rift Valley Fever Virus Engages the F-Box Proteins FBXW11 and ?-TRCP1 To Degrade the Antiviral Protein Kinase PKR. J Virol 90:6140-7
George, Cyril X; Ramaswami, Gokul; Li, Jin Billy et al. (2016) Editing of Cellular Self-RNAs by Adenosine Deaminase ADAR1 Suppresses Innate Immune Stress Responses. J Biol Chem 291:6158-68
George, Cyril X; Samuel, Charles E (2015) STAT2-dependent induction of RNA adenosine deaminase ADAR1 by type I interferon differs between mouse and human cells in the requirement for STAT1. Virology 485:363-70
Wu, Chengjun; Bai, Lufeng; Li, Zhiqun et al. (2015) Poor growth of human adenovirus-12 compared to adenovirus-2 correlates with a failure to impair PKR activation during the late phase of infection. Virology 475:120-8
Pfaller, Christian K; Mastorakos, George M; Matchett, William E et al. (2015) Measles Virus Defective Interfering RNAs Are Generated Frequently and Early in the Absence of C Protein and Can Be Destabilized by Adenosine Deaminase Acting on RNA-1-Like Hypermutations. J Virol 89:7735-47
Pfaller, Christian K; Radeke, Monte J; Cattaneo, Roberto et al. (2014) Measles virus C protein impairs production of defective copyback double-stranded viral RNA and activation of protein kinase R. J Virol 88:456-68
John, Lijo; Samuel, Charles E (2014) Induction of stress granules by interferon and down-regulation by the cellular RNA adenosine deaminase ADAR1. Virology 454-455:299-310
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