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Selective enhancement of nucleases by polyvalent DNA-functionalized gold nanoparticles.

ABSTRACT: We demonstrate that polyvalent DNA-functionalized gold nanoparticles (DNA-Au NPs) selectively enhance ribonuclease H (RNase H) activity while inhibiting most biologically relevant nucleases. This combination of properties is particularly interesting in the context of gene regulation, since high RNase H activity results in rapid mRNA degradation and general nuclease inhibition results in high biological stability. We have investigated the mechanism of selective RNase H activation and found that the high DNA density of DNA-Au NPs is responsible for this unusual behavior. This work adds to our understanding of polyvalent DNA-Au NPs as gene regulation agents and suggests a new model for selectively controlling protein-nanoparticle interactions.

SUBMITTER: Prigodich AE

PROVIDER: S-EPMC3081637 | biostudies-literature | 2011 Feb

REPOSITORIES: biostudies-literature

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Selective enhancement of nucleases by polyvalent DNA-functionalized gold nanoparticles.

Prigodich Andrew E AE Alhasan Ali H AH Mirkin Chad A CA

Journal of the American Chemical Society 20110126 7

We demonstrate that polyvalent DNA-functionalized gold nanoparticles (DNA-Au NPs) selectively enhance ribonuclease H (RNase H) activity while inhibiting most biologically relevant nucleases. This combination of properties is particularly interesting in the context of gene regulation, since high RNase H activity results in rapid mRNA degradation and general nuclease inhibition results in high biological stability. We have investigated the mechanism of selective RNase H activation and found that t ...[more]

PMID: 21268581

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