Nature Biotechnology
20, 497 - 500 (2002)
doi:10.1038/nbt0502-497
U6 promoter−driven siRNAs with four uridine 3' overhangs
efficiently suppress targeted gene expression in mammalian cellsMakoto Miyagishi1
& Kazunari Taira1, 21
Department of Chemistry and Biotechnology, School
of Engineering, the University of Tokyo, Hongo, Tokyo
113-8656, Japan. 2
Gene Discovery Research Center, National Institute
of Advanced Industrial Science and Technology (AIST), 1-1-4
Higashi, Tsukuba Science City 305-8562,
Japan.
Correspondence should be addressed to Kazunari Taira taira@chembio.t.u-tokyo.ac.jpThe first evidence for gene disruption by double-stranded RNA
(dsRNA) came from careful analysis in Caenorhabditis elegans
1. This phenomenon, called RNA interference (RNAi), was observed
subsequently in various organisms, including plants, nematodes,
Drosophila, and protozoans2,
3,
4,
5. Very recently, it
has been reported that in mammalian cells, 21- or 22-nucleotide (nt) RNAs with
2-nt 3' overhangs (small inhibitory RNAs, siRNAs) exhibit an RNAi
effect6,
7. This is because siRNAs are not recognized by the
well-characterized host defense system against viral infections, involving
dsRNA-dependent inhibition of protein synthesis. However, the current method
for introducing synthetic siRNA into cells by lipofection restricts the range
of applications of RNAi as a result of the low transfection efficiencies in
some cell types and/or short-term persistence of silencing effects8. Here, we report a vector-based siRNA expression system that can
induce RNAi in mammalian cells. This technical advance for silencing gene
expression not only facilitates a wide range of functional analysis of
mammalian genes but might also allow therapeutic applications by means of
vector-mediated RNAi.
|
