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Modulation of ADAR1 editing activity by Z-RNA in vitro.

ABSTRACT: RNA editing by A-to-I modification has been recognized as an important molecular mechanism for generating RNA and protein diversity. In mammals, it is mediated by a family of adenosine deaminases that act on RNAs (ADARs). The large version of the editing enzyme ADAR1 (ADAR1-L), expressed from an interferon-responsible promoter, has a Z-DNA/Z-RNA binding domain at its N-terminus. We have tested the in vitro ability of the enzyme to act on a 50 bp segment of dsRNA with or without a Z-RNA forming nucleotide sequence. A-to-I editing efficiency is markedly enhanced in presence of the sequence favoring Z-RNA. In addition, an alteration in the pattern of modification along the RNA duplex becomes evident as reaction times decrease. These results suggest that the local conformation of dsRNA molecules might be an important feature for target selectivity by ADAR1 and other proteins with Z-RNA binding domains.

SUBMITTER: Koeris M

PROVIDER: S-EPMC1226316 | biostudies-literature | 2005

REPOSITORIES: biostudies-literature

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Modulation of ADAR1 editing activity by Z-RNA in vitro.

Koeris Michael M Funke Lars L Shrestha Jay J Rich Alexander A Maas Stefan S

Nucleic acids research 20050921 16

RNA editing by A-to-I modification has been recognized as an important molecular mechanism for generating RNA and protein diversity. In mammals, it is mediated by a family of adenosine deaminases that act on RNAs (ADARs). The large version of the editing enzyme ADAR1 (ADAR1-L), expressed from an interferon-responsible promoter, has a Z-DNA/Z-RNA binding domain at its N-terminus. We have tested the in vitro ability of the enzyme to act on a 50 bp segment of dsRNA with or without a Z-RNA forming n ...[more]

PMID: 16177183

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ADAR1-Mediated RNA Editing, A Novel Mechanism Controlling Phenotypic Modulation of Vascular Smooth Muscle Cells.

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Chromosomal storage of the RNA-editing enzyme ADAR1 in Xenopus oocytes.

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