PMCC PMCC

Search tips
Search criteria

Advanced
Results 1-2 (2)
 

Clipboard (0)
None
Journals
Authors
Year of Publication
Document Types
1.  Enzymatic synthesis of DNA strands containing α-L-LNA (α-L-configured locked nucleic acid) thymine nucleotides 
Artificial DNA, PNA & XNA  2012;3(1):14-21.
We describe the first enzymatic incorporation of an α-L-LNA nucleotide into an oligonucleotide. It was found that the 5′-triphosphate of α-L-LNA is a substrate for the DNA polymerases KOD, 9°Nm, Phusion and HIV RT. Three dispersed α-L-LNA thymine nucleotides can be incorporated into DNA strands by all four polymerases, but they were unable to perform consecutive incorporations of α-L-LNA nucleotides. In addition it was found that primer extension can be achieved using templates containing one α-L-LNA nucleotide.
doi:10.4161/adna.19272
PMCID: PMC3368812  PMID: 22679529
enzymatic synthesis; modified nucleotide; polymerase; triphosphate; α-L-LNA
2.  In vivo efficacy and off-target effects of locked nucleic acid (LNA) and unlocked nucleic acid (UNA) modified siRNA and small internally segmented interfering RNA (sisiRNA) in mice bearing human tumor xenografts 
Artificial DNA, PNA & XNA  2010;1(1):36-44.
The clinical use of small interfering RNA (siRNA) is hampered by poor uptake by tissues and instability in circulation. In addition, off-target effects pose a significant additional problem for therapeutic use of siRNA. Chemical modifications of siRNA have been reported to increase stability and reduce off-target effects enabling possible therapeutic use of siRNA. Recently a large scale direct comparison of the impact of 21 different types of novel chemical modifications on siRNA efficiency and cell viability was published.1 It was found that several types of chemical modifications could enhance siRNA activity beyond that of an unmodified siRNA in vitro. In addition, a novel siRNA design, termed small internally segmented interfering RNA (sisiRNA), composed of an intact antisense strand and segmented guide strand stabilized using LNA was shown to be effective in cell based assays. In the present study we examined the in vivo efficacy of the LNA and UNA modified siRNA and sisiRNA in a mouse model bearing human tumor xenografts. We studied the biodistribution and efficacy of target knockdown in the mouse model. In addition we used whole genome profiling to assess the off-target effects in the liver of the mouse and the tumor xenografts. We report that LNA and UNA modified siRNA and sisiRNA improve the efficacy in target knockdown as compared with unmodified siRNA in the tumor xenografts without formulation. However, the level of off-target gene regulation in both the tumor and the liver correlated with the increase in efficacy in target knockdown, unless the seed region of the siRNA was modified.
doi:10.4161/adna.1.1.12204
PMCID: PMC3109444  PMID: 21687525
LNA; unlocked nucleic acid; siRNA; sisiRNA; off-target effects

Results 1-2 (2)