Download MendeleyStructure of the double-stranded RNA-binding domain of the protein kinase PKR reveals the molecular basis of its dsRNA-mediated activation.
Nanduri, S., Carpick, B.W., Yang, Y., Williams, B.R., Qin, J.(1998) EMBO J 17: 5458-5465
- PubMed: 9736623
- DOI: https://doi.org/10.1093/emboj/17.18.5458
- Primary Citation of Related Structures:
1QU6 - PubMed Abstract:
Protein kinase PKR is an interferon-induced enzyme that plays a key role in the control of viral infections and cellular homeostasis. Compared with other known kinases, PKR is activated by a distinct mechanism that involves double-stranded RNA (dsRNA) binding in its N-terminal region in an RNA sequence-independent fashion. We report here the solution structure of the 20 kDa dsRNA-binding domain (dsRBD) of human PKR, which provides the first three-dimensional insight into the mechanism of its dsRNA-mediated activation. The structure of dsRBD exhibits a dumb-bell shape comprising two tandem linked dsRNA-binding motifs (dsRBMs) both with an alpha-beta-beta-beta-alpha fold. The structure, combined with previous mutational and biochemical data, reveals a highly conserved RNA-binding site on each dsRBM and suggests a novel mode of protein-RNA recognition. The central linker is highly flexible, which may enable the two dsRBMs to wrap around the RNA duplex for cooperative and high-affinity binding, leading to the overall change of PKR conformation and its activation.
Organizational Affiliation:
Structural Biology Program, Lerner Research Institute, The Cleveland Clinic Foundation, 9500 Euclid Avenue, Cleveland, OH 44195, USA.
