Zinc finger proteins as molecular targets for nitric oxide-mediated gene regulation.

A multiplicity of biological functions have been ascribed to nitric oxide (NO). It plays a significant role as a signal as well as a cytotoxic effector molecule. NO may, however, also play regulatory and/or modulatory roles in biology. A growing body of evidence suggests that posttranslational modifications of transcription factors serve a regulating role on gene transcription, particularly after changes of the redox state of the cell. Zinc fingers are the most prevalent transcription factor DNA-binding motif. As NO is able to S-nitrosate thiols of zinc-sulfur clusters leading to reversible disruption of zinc finger structures, this provides a molecular mechanism to regulate the transcription of genes. Current knowledge about effects of NO on the cellular zinc homeostasis and on the gene-regulating activity of zinc finger transcription factors is reviewed.