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Covalent stabilization of a small molecule-RNA complex.

ABSTRACT: We demonstrate covalent bond formation between an RNA aptamer containing a cysteamine-tethered nucleobase and helix-threading peptides (HTPs) containing ?-bromoacetamide N-termini. The reaction is high yielding and inhibited by a DNA strand Watson-Crick complementary to the aptamer sequence indicating covalent reaction is dependent on the high affinity HTP-binding site present in the folded aptamer. These results are important for future structural studies of HTP-RNA complexes and methods for the discovery of new high affinity analogs via covalent tethering strategies.

SUBMITTER: Peacock H

PROVIDER: S-EPMC3156283 | biostudies-literature | 2011 Sep

REPOSITORIES: biostudies-literature

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Covalent stabilization of a small molecule-RNA complex.

Peacock Hayden H Bachu Radhika R Beal Peter A PA

Bioorganic & medicinal chemistry letters 20110505 17

We demonstrate covalent bond formation between an RNA aptamer containing a cysteamine-tethered nucleobase and helix-threading peptides (HTPs) containing α-bromoacetamide N-termini. The reaction is high yielding and inhibited by a DNA strand Watson-Crick complementary to the aptamer sequence indicating covalent reaction is dependent on the high affinity HTP-binding site present in the folded aptamer. These results are important for future structural studies of HTP-RNA complexes and methods for th ...[more]

PMID: 21601451

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