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Use of Guanidinopropyl-Modified siRNAs to Silence Gene Expression

Protocol
First Online:
Part of the Methods in Molecular Biology book series (MIMB, volume 1218)

Abstract

Silencing gene expression by harnessing the RNA interference (RNAi) pathway with short interfering RNAs (siRNAs) has useful analytical and potentially therapeutic application. To augment silencing efficacy of siRNAs, chemical modification has been employed to improve stability, target specificity, and delivery to target tissues. siRNAs incorporating guanidinopropyl (GP) moieties have demonstrated enhanced target gene silencing in cell culture and in vivo models of hepatitis B virus replication. Here we describe the synthesis of GP-modified siRNAs and use of 5′ rapid amplification of cDNA ends (5′ RACE) to verify an RNAi-mediated mechanism of action of these novel chemically modified siRNAs.

Key words

siRNA RNAi RNA Oligonucleotide synthesis Guanidinopropyl HBV 5′ RACE 
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Notes

Acknowledgements

We gratefully acknowledge financial assistance from the Ernst & Ethel Eriksen Trust, National Research Foundation of South Africa (NRF), Medical Research Council, the Poliomyelitis Research Foundation (PRF) and from the German Research Foundation (DFG). We also thankfully acknowledge the helpful assistance of Corvin Steidinger, Christian Schuch, and Timo Weinrich in the synthesis of the GP-modified monomers.

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Copyright information

© Springer Science+Business Media New York 2015

Authors and Affiliations

  1. 1.Institute of Organic Chemistry & Chemical BiologyGoethe-UniversityFrankfurt am MainGermany
  2. 2.Antiviral Gene Therapy Research Unit and African Network for Drugs and Diagnostics Innovation (ANDI) Centre of Excellence, School of Pathology, Health Sciences Faculty, University of the Witwatersrand Medical SchoolUniversity of the WitwatersrandJohannesburgSouth Africa
  3. 3.Antiviral Gene Therapy Research UnitUniversity of the Witwatersrand Medical SchoolJohannesburgSouth Africa

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