Modified RNAi polynucleotides and uses thereof
First Claim
1. A blunt-ended double-stranded RNA (dsRNA) construct, for inhibiting expression of a target gene, comprising a sense strand of 25, 26, 27, 28, 29, or 30 nucleotides in length, having a 5′
- -end and a 3′
-end, wherein the sense strand consists of 2′
-modified ribose sugars except for nucleotides 11, 12, and 13 relative to the 3′
-end of the sense strand, which prevents processing of the double-stranded RNA construct by Dicer, and an antisense strand of 25, 26, 27, 28, 29, or 30 nucleotides in length having a 5′
-end and a 3′
-end, wherein the antisense strand is unmodified, wherein the antisense strand hybridizes to the sense strand and to mRNA of the target gene, wherein the dsRNA inhibits expression of the target gene in a sequence-dependent manner, and wherein the dsRNA does not form a hairpin.
6 Assignments
0 Petitions
Accused Products
Abstract
The invention relates to improved RNAi constructs and uses thereof. The construct has a double stranded region of 19-49 nucleotides, preferably 25, 26, or 27 nucleotides, and preferably blunt-ended. The construct has selective minimal modifications to confer an optimal balance of biological activity, toxicity, stability, and target gene specificity. For example, the sense strand may be modified (e.g., one or both ends of the sense strand is/are modified by four 2′-O-methyl groups), such that the construct is not cleaved by Dicer or other RNAse III, and the entire length of the antisense strand is loaded into RISC. In addition, the antisense strand may also be modified by 2′-O-methyl group at the 2nd 5′-end nucleotide to greatly reduce off-target silencing. The constructs of the invention largely avoids the interferon response and sequence-independent apoptosis in mammalian cells, exhibits better serum stability, and enhanced target specificity.
276 Citations
8 Claims
-
1. A blunt-ended double-stranded RNA (dsRNA) construct, for inhibiting expression of a target gene, comprising a sense strand of 25, 26, 27, 28, 29, or 30 nucleotides in length, having a 5′
- -end and a 3′
-end, wherein the sense strand consists of 2′
-modified ribose sugars except for nucleotides 11, 12, and 13 relative to the 3′
-end of the sense strand, which prevents processing of the double-stranded RNA construct by Dicer, and an antisense strand of 25, 26, 27, 28, 29, or 30 nucleotides in length having a 5′
-end and a 3′
-end, wherein the antisense strand is unmodified, wherein the antisense strand hybridizes to the sense strand and to mRNA of the target gene, wherein the dsRNA inhibits expression of the target gene in a sequence-dependent manner, and wherein the dsRNA does not form a hairpin. - View Dependent Claims (2, 3, 4, 5, 6, 7)
- -end and a 3′
-
8. A blunt-ended double-stranded RNA (dsRNA) construct comprising a sense strand having a 5′
- -end and a 3′
-end, wherein the sense strand is 25, 26 or 27 nucleotides in length, and an antisense strand having a 5′
-end and a 3′
-end, wherein the antisense strand is 25, 26 or 27 nucleotides in length, for inhibiting expression of a target gene, wherein the sense strand consists of 2′
-modified ribose sugars except for nucleotides 11, 12 and 13 relative to the 3′
end of the sense strand, which prevents processing of the double-stranded RNA construct by Dicer, and wherein the dsRNA does not form a hairpin.
- -end and a 3′
Specification