US 7,056,704 B2 · RNA interference mediating small RNA molecules

Abstract

Double-stranded RNA (dsRNA) induces sequence-specific post-transcriptional gene silencing in many organisms by a process known as RNA interference (RNAi). Using a Drosophila in vitro system, we demonstrate that 19–23 nt short RNA fragments are the sequence-specific mediators of RNAi. The short interfering RNAs (siRNAs) are generated by an RNase III-like processing reaction from long dsRNA. Chemically synthesized siRNA duplexes with overhanging 3′ ends mediate efficient target RNA cleavage in the lysate, and the cleavage site is located near the center of the region spanned by the guiding siRNA. Furthermore, we provide evidence that the direction of dsRNA processing determines whether sense or antisense target RNA can be cleaved by the produced siRNP complex.

Claims15

Dependent claims

A method for preparing a double stranded RNA molecule which mediates the cleavage of an mRNA in a mammalian cell, comprising

(a) synthesizing two RNA strands each having a length from 19–25 nucleotides, and
(b) combining the synthesized RNA strands under conditions suitable to form a double stranded RNA molecule, wherein said double stranded RNA molecule has a double stranded region of 14–24 nucleotides in length and one or two 3′ overhang regions of 1–5 nucleotides in length.

Dependencies are inferred from the claim text.

RNA interference mediating small RNA molecules

Life of this patent

RNA interference mediating small RNA molecules

Life of this patent

Abstract

Claims15