Template-dependent incorporation of 8-N3AMP into RNA with bacteriophage T7 RNA polymerase
| Autor: | Saurabh Sahar, Sailesh Gopalakrishna, Sethulekshmy Nair, Veronica Gusti, Rajesh K. Gaur |
|---|---|
| Rok vydání: | 2004 |
| Předmět: |
Azides
Transcription Genetic Ultraviolet Rays Termination factor RNA-dependent RNA polymerase Method RNA polymerase II Photoaffinity Labels Substrate Specificity Viral Proteins Adenosine Triphosphate Transcription (biology) Bacteriophage T7 RNA polymerase I medicine Escherichia coli T7 RNA polymerase Magnesium Molecular Biology Polymerase Manganese biology RNA DNA-Directed RNA Polymerases Templates Genetic Kinetics Cross-Linking Reagents Biochemistry biology.protein medicine.drug |
| Zdroj: | RNA (New York, N.Y.). 10(11) |
| ISSN: | 1355-8382 |
| Popis: | UV-induced photochemical crosslinking is a powerful approach that can be used for the identification of specific interactions involving nucleic acid-protein and nucleic acid-nucleic acid complexes. 8-AzidoATP (8-N3ATP) is a photoaffinity-labeling agent which has been widely used to elucidate the ATP binding site of a variety of proteins. However, its true potential as a photoactivatable nucleotide analog could not be exploited due to the lack of 8-azidoadenosine phosphoramidite, a monomer used in the synthesis of RNA, and the inability of 8-N3ATP to serve as an efficient substrate for bacteriophage RNA polymerase. In this study, we explored the ability of SP6, T3, and T7 RNA polymerases and metal ion cofactors to catalyze the incorporation of 8-N3AMP into RNA. Whereas transcription buffer containing 2.0–2.5 mM Mn2+ supports T7 RNA polymerase-mediated insertion of 8-N3AMP into RNA, a mixture of 2.5 mM Mn2+ and 2.5 mM Mg2+ further improves the yield of 8-N3AMP-containing transcript. In addition, both RNA transcription and reverse transcription proceed with high fidelity for the incorporation of 8-N3AMP and complementary residue, respectively. Finally, we show that a high-affinity MS2 coat protein binding sequence, in which adenosine residues were replaced by 8-azidoadenosine, crosslinks to the coat protein of the Escherichia coli phage MS2. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|