Thomas,
I've not followed RZYM for a long time. I don't know what bona fide biofreaks do. Nigel keeps well informed and bought some a while back, don't know what he did with it.
RZYM's publications don't make direct reference to siRNA, nor do they say much about their IP. I looked at their site and found it unhelpful for DD of that nature. As you may have gathered if you've read the thread, there is some controversy over how specific siRNA is, though most studies seem to affirm its specificity.
This is separate from the delivery issue, which is probably addressable in a number of ways. It remains to see which will be the most viable. It's early, and this thread is for watching the whole thing unfold. Below is another hot off the press abstract that pertains somewhat to the delivery issue. Synthetic siRNAs seemed to in the back of the pack, but perhaps this puts them back in contention.
>>Nucleic Acids Res 2003 Jun 1;31(11):2705-16
Structural variations and stabilising modifications of synthetic siRNAs in mammalian cells.
Czauderna F, Fechtner M, Dames S, Aygun H, Klippel A, Pronk GJ, Giese K, Kaufmann J.
Atugen AG, Otto Warburg Haus (No. 80), Robert-Roessle-Strasse 10, 13125 Berlin, Germany.
Double-stranded short interfering RNAs (siRNA) induce post-transcriptional silencing in a variety of biological systems. In the present study we have investigated the structural requirements of chemically synthesised siRNAs to mediate efficient gene silencing in mammalian cells. In contrast to studies with Drosophila extracts, we found that synthetic, double-stranded siRNAs without specific nucleotide overhangs are highly efficient in gene silencing. Blocking of the 5'-hydroxyl terminus of the antisense strand leads to a dramatic loss of RNA interference activity, whereas blocking of the 3' terminus or blocking of the termini of the sense strand had no negative effect. We further demonstrate that synthetic siRNA molecules with internal 2'-O-methyl modification, but not molecules with terminal modifications, are protected against serum-derived nucleases. Finally, we analysed different sets of siRNA molecules with various 2'-O-methyl modifications for stability and activity. We demonstrate that 2'-O-methyl modifications at specific positions in the molecule improve stability of siRNAs in serum and are tolerated without significant loss of RNA interference activity. These second generation siRNAs will be better suited for potential therapeutic application of synthetic siRNAs in vivo.<<
Cheers, Tuck |
