Left-handed Z-DNA: structure and function.

A Herbert; A Rich

doi:10.1023/a:1003768526018

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PubMed · 10710708

Left-handed Z-DNA: structure and function.

A Herbert·A Rich

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Abstract

Z-DNA is a high energy conformer of B-DNA that forms in vivo during transcription as a result of torsional strain generated by a moving polymerase. An understanding of the biological role of Z-DNA has advanced with the discovery that the RNA editing enzyme double-stranded RNA adenosine deaminase type I (ADAR1) has motifs specific for the Z-DNA conformation. Editing by ADAR1 requires a double-stranded RNA substrate. In the cases known, the substrate is formed by folding an intron back onto the exon that is targeted for modification. The use of introns to direct processing of exons requires that editing occurs before splicing. Recognition of Z-DNA by ADAR1 may allow editing of nascent transcripts to be initiated immediately after transcription, ensuring that editing and splicing are performed in the correct sequence. Structural characterization of the Z-DNA binding domain indicates that it belongs to the winged helix-turn-helix class of proteins and is similar to the globular domain of histone-H5.

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Adenosine Deaminase Amino Acid Motifs Animals DNA DNA-Binding Proteins Eukaryotic Cells Magnetic Resonance Spectroscopy Nucleic Acid Conformation Prokaryotic Cells Protein Binding Protein Structure, Tertiary RNA Editing RNA-Binding Proteins NASA Discipline Exobiology Non-NASA Center Journal Article Review

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A Herbert, A Rich. 1999. Left-handed Z-DNA: structure and function.. https://doi.org/10.1023/a%3A1003768526018

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