TY  - JOUR
A1  - Bramsen, Jesper B.
A1  - Pakula, Malgorzata M.
A1  - Hansen, Thomas B.
A1  - Bus, Claus
A1  - Langkjær, Niels
A1  - Odadžić, Dalibor
A1  - Smicius, Romualdas
A1  - Wengel, Suzy L.
A1  - Chattopadhyaya, Jyoti
A1  - Engels, Joachim W.
A1  - Herdewijn, Piet
A1  - Wengel, Jesper
A1  - Kjems, Jørgen
T1  - A screen of chemical modifications identifies position-specific modification by UNA to most potently reduce siRNA off-target effects
T2  - Nucleic acids research
N2  - Small interfering RNAs (siRNAs) are now established as the preferred tool to inhibit gene function in mammalian cells yet trigger unintended gene silencing due to their inherent miRNA-like behavior. Such off-target effects are primarily mediated by the sequence-specific interaction between the siRNA seed regions (position 2–8 of either siRNA strand counting from the 5'-end) and complementary sequences in the 3'UTR of (off-) targets. It was previously shown that chemical modification of siRNAs can reduce off-targeting but only very few modifications have been tested leaving more to be identified. Here we developed a luciferase reporter-based assay suitable to monitor siRNA off-targeting in a high throughput manner using stable cell lines. We investigated the impact of chemically modifying single nucleotide positions within the siRNA seed on siRNA function and off-targeting using 10 different types of chemical modifications, three different target sequences and three siRNA concentrations. We found several differently modified siRNAs to exercise reduced off-targeting yet incorporation of the strongly destabilizing unlocked nucleic acid (UNA) modification into position 7 of the siRNA most potently reduced off-targeting for all tested sequences. Notably, such position-specific destabilization of siRNA–target interactions did not significantly reduce siRNA potency and is therefore well suited for future siRNA designs especially for applications in vivo where siRNA concentrations, expectedly, will be low.
Y1  - 2010
UR  - http://publikationen.ub.uni-frankfurt.de/frontdoor/index/index/docId/8037
UR  - https://nbn-resolving.org/urn:nbn:de:hebis:30-79873
SN  - 1362-4962
SN  - 0305-1048
N1  - © The Author(s) 2010. Published by Oxford University Press. This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/2.5), which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.
VL  - 38
IS  - 17
SP  - 5761
EP  - 5773
PB  - Oxford Univ. Press
CY  - Oxford
ER  -