Chimeric double-stranded RNA-specific adenosine deaminase ADAR1 proteins reveal functional selectivity of double-stranded RNA-binding domains from ADAR1 and protein kinase PKR.

ABSTRACT: The RNA-specific adenosine deaminase (ADAR1) and the RNA-dependent protein kinase (PKR) are both interferon-inducible double-stranded (ds) RNA-binding proteins. ADAR1, an RNA editing enzyme that converts adenosine to inosine, possesses three copies of a dsRNA-binding motif (dsRBM). PKR, a regulator of translation, has two copies of the highly conserved dsRBM motif. To assess the functional selectivity of the dsRBM motifs in ADAR1, we constructed and characterized chimeric proteins in which the dsRBMs of ADAR1 were substituted with those of PKR. Recombinant PKR-ADAR1 chimeras retained significant RNA adenosine deaminase activity measured with a synthetic dsRNA substrate when the spacer region between the RNA-binding and catalytic domains of the deaminase was exactly preserved. However, with

SUBMITTER: Liu Y 

PROVIDER: S-EPMC18800 | biostudies-literature | 2000 Nov

REPOSITORIES: biostudies-literature