Oligoribonucleotide derivatives for specific inhibition of gene expression

Abstract

The present invention relates to oligoribonucleotide derivatives which have a 2′5′-linked oligoribonucleotide residue without a 5′-phosphate residue on the 3′ end and to the use thereof for specific inhibition of gene expression.

Patent claims:  
     
         1 . An oligonucleotide of the formula I 
       5′-(N) x —(Z) n   Formula I 
       where 
 N is naturally or not naturally occurring nucleotides which are at least partly complementary to a target RNA,  
 x is independently 10 to 100,  
 n is 2 to 20,  
 Z is naturally or not naturally occurring nucleotides which are linked via a 2′5′ internucleoside bond.  
 with the proviso that its homologous target RNA has one of the following sequence patterns.  
 5′-(U) v —(N) z —(U) w    
 5′-(U) v —(N) z —UX  
 5′-UX—(N) z —UX and  
 5′-(U) v —(N) z , 
 where v is independently 2 to 20,  
 where w is independently 2 to 20,  
 z is independently 15 to 25,  
 U is uridine, N is adenosine (A), guanosine (G), cytidine (C) or U and X is A, G or C, preferably A  
 and to its physiologically tolerated salts.  
 
 
     
     
         2 . The oligonucleotide of the formula I as claimed in  claim 1 , wherein x is 15 to 45.  
     
     
         3 . The oligonucleotide of the formula I as claimed in  claim 2 , wherein x is 16 to 25.  
     
     
         4 . The oligonucleotide of the formula I as claimed in one or more of  claims 1  to  3 , wherein n is 2 to 10.  
     
     
         5 . The oligonucleotide of the formula I as claimed in  claim 4 , wherein n is 3 to 6.  
     
     
         6 . The oligonucleotide of the formula I as claimed in one or more of  claims 1  to  5 , wherein N is a ribonucleotide.  
     
     
         7 . The oligonucleotide of the formula I as claimed in one or more of  claims 1  to  6 , wherein v is 2 to 10.  
     
     
         8 . The oligonucleotide of the formula I as claimed in  claim 7 , wherein v is 3 to 6.  
     
     
         9 . The oligonucleotide of the formula I as claimed in one or more of  claims 6  to  8 , wherein w is 2 to 10.  
     
     
         10 . The oligonucleotide of the formula I as claimed in  claim 9 , wherein w is  3  to 6.  
     
     
         11 . The oligonucleotide of the formula I as claimed in one or more of  claims 1  to  10 , wherein z is 16 to 23.  
     
     
         12 . The oligonucleotide of the formula I as claimed in  claim 11 , wherein z is 19 to 21.  
     
     
         13 . The oligonucleotide of the formula I as claimed in one or more of  claims 1  to  12 , wherein Z is adenosine or 3′-deoxyadenosine.  
     
     
         14 . The oligonucleotide of the formula I as claimed in one or more of  claims 1  to  13 , in which one or more natural phosphodiester bonds have been replaced by unnatural internucleotide bonds which stabilize against nuclease degradation.  
     
     
         15 . The oligonucleotide of the formula I as claimed in one or more of  claims 1  to  14 , in which one or more natural phosphodiester bonds have been replaced by phosphorothioate bonds.  
     
     
         16 . The oligonucleotide of the formula I as claimed in one or more of  claims 1  to  15 , in which a plurality of natural phosphodiester bonds have been replaced by phosphorothioate bonds, with said modifications being located on the ends and on internal pyrimidine nucleotides.  
     
     
         17 . A method for inhibiting gene expression of a target gene in a cell with the aid of one or more oligonucleotides as claimed in one or more of  claims 1  to  16 , wherein first an oligonucleotide complementary to an appropriate target gene is prepared, said oligonucleotide is introduced into a cell, said cell is incubated and inhibition of the gene expression of the target gene is then determined by comparative measurements of the amount of the corresponding mRNA or corresponding gene product in a control cell.  
     
     
         18 . The method as claimed in  claim 17  for inhibiting gene expression of a target gene in a cell in which 2′5′-oligoadenylate synthase is underexpressed in comparison with a control cell or is defective.  
     
     
         19 . A pharmaceutical comprising an oligonucleotide as claimed in one or more of  claims 1  to  18  and also additives and/or carriers and, where appropriate, excipients for preparing or formulating a pharmaceutical.  
     
     
         20 . The use of a pharmaceutical as claimed in  claim 19  in tumor therapy.  
     
     
         21 . The use of a pharmaceutical as claimed in  claim 19  in the therapy or prevention of infectious diseases.  
     
     
         22 . The use of a pharmaceutical as claimed in  claim 19  in the therapy or prevention of viral diseases.  
     
     
         23 . The use of a pharmaceutical as claimed in  claim 19  in the therapy of inflammations or asthma.  
     
     
         24 . The use of a pharmaceutical as claimed in  claim 19  in the therapy of cardiovascular or metabolic disorders.  
     
     
         25 . The use of an oligonucleotide as claimed in one or more of  claims 1  to  16  for identifying or validating novel therapeutic target genes.  
     
     
         26 . The use of an oligonucleotide as claimed in one or more of  claims 1  to  16  for identifying or validating novel target genes in crop protection research.  
     
     
         27 . A method for preparing an oligonucleotide as claimed in one or more of  claims 1  to  16 , wherein the oligonucleotides are first prepared in solution or on the solid phase by successive coupling or coupling in blocks and are, after the preparation, isolated and purified.  
     
     
         28 . A method for preparing a pharmaceutical, wherein an oligonucleotide derivative as claimed in  claim 27  is prepared and, where appropriate, admixed with further additives and/or carriers and, where appropriate, excipients.