Journal of RNAi and Gene Silencing (May 2008), 4(1), 295-301

Short Report

Native microRNA loop sequences can improve short hairpin RNA processing for virus gene silencing in animal cells

Tracey M Hinton †‡*Terry G Wise †, Pauline A Cottee †, Timothy J Doran †‡

ABSTRACT

Introduction of small interfering RNAs (siRNAs) into cells results in transitory silencing of target genes with complementary sequence. Incorporating siRNAs into short-hairpin RNAs (shRNAs) or microRNA-adapted shRNAs (shRNAmir) is a popular tool for targeted gene silencing. shRNAmirs mimicking endogenous pre-microRNAs (unprocessed hairpin microRNAs) are more difficult to design and result in longer RNA molecules. The use of microRNA (miRNA) loop sequences in shRNAs as an alternative to an entire pre-microRNA structure on silencing efficiency has not been studied extensively. This report shows that loop sequences derived from native miRNAs improves the efficiency of silencing due to the processing of the shRNAs into mature siRNAs.

KEYWORDS: microRNA; RNA interference; short hairpin RNA, influenza

†CSIRO Livestock Industries, Australian Animal Health Laboratory, Geelong 3220, Australia

‡Cooperative Research Centre for the Australian Poultry Industry, Armidale, NSW, 2315, Australia

*Correspondence to: Tracy Hinton, Email: Tracey.Hinton@csiro.au, Tel: +61 3 52275746 , Fax: +61 3 52275555

© Copyright The Authors

( Received 19 March 2008; Revised 06 May 2008; Accepted 14 May 2008)