OPEN ACCESS ARTICLE

This Article Free via Open Access: OA OA Full Text Full Text (PDF) Supplemental Data OA All Versions of this Article: 142/1/6    most recent pp.106.084517v1 Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in ISI Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via ISI Web of Science (8) Citing Articles via Google Scholar Google Scholar Articles by Travella, S. Articles by Keller, B. Search for Related Content PubMed PubMed Citation Articles by Travella, S. Articles by Keller, B. Agricola Articles by Travella, S. Articles by Keller, B. Related Collections Vector Systems for Plant Research and Biotechnology

GENOME ANALYSIS

RNA Interference-Based Gene Silencing as an Efficient Tool for Functional Genomics in Hexaploid Bread Wheat^1,[W],[OA]

Institute of Plant Biology, University of Zurich, 8008 Zurich, Switzerland

Insertional mutagenesis and gene silencing are efficient tools for the determination of gene function. In contrast to gain- or loss-of-function approaches, RNA interference (RNAi)-induced gene silencing can possibly silence multigene families and homoeologous genes in polyploids. This is of great importance for functional studies in hexaploid wheat (Triticum aestivum), where most of the genes are present in at least three homoeologous copies and conventional insertional mutagenesis is not effective. We have introduced into bread wheat double-stranded RNA-expressing constructs containing fragments of genes encoding Phytoene Desaturase (PDS) or the signal transducer of ethylene, Ethylene Insensitive 2 (EIN2). Transformed plants showed phenotypic changes that were stably inherited over at least two generations. These changes were very similar to mutant phenotypes of the two genes in diploid model plants. Quantitative real-time polymerase chain reaction revealed a good correlation between decreasing mRNA levels and increasingly severe phenotypes. RNAi silencing had the same quantitative effect on all three homoeologous genes. The most severe phenotypes were observed in homozygous plants that showed the strongest mRNA reduction and, interestingly, produced around 2-fold the amount of small RNAs compared to heterozygous plants. This suggests that the effect of RNAi in hexaploid wheat is gene-dosage dependent. Wheat seedlings with low mRNA levels for EIN2 were ethylene insensitive. Thus, EIN2 is a positive regulator of the ethylene-signaling pathway in wheat, very similar to its homologs in Arabidopsis (Arabidopsis thaliana) and rice (Oryza sativa). Our data show that RNAi results in stably inherited phenotypes and therefore represents an efficient tool for functional genomic studies in polyploid wheat.

The author responsible for distribution of materials integral to the findings presented in this article in accordance with the policy described in the Instructions for Authors (www.plantphysiol.org) is: Beat Keller (bkeller{at}botinst.unizh.ch).

^[W] The online version of this article contains Web-only data.

^[OA] Open Access articles can be viewed online without a subscription.

www.plantphysiol.org/cgi/doi/10.1104/pp.106.084517

^* Corresponding author; e-mail bkeller{at}botinst.unizh.ch; fax 41–44–634–82–04.

Received June 2, 2006; accepted July 12, 2006.

This article has been cited by other articles:

				M. Dafny-Yelin, S.-M. Chung, E. L. Frankman, and T. Tzfira pSAT RNA Interference Vectors: A Modular Series for Multiple Gene Down-Regulation in Plants Plant Physiology, December 1, 2007; 145(4): 1272 - 1281. [Abstract] [Full Text] [PDF]

				K. McGinnis, N. Murphy, A. R. Carlson, A. Akula, C. Akula, H. Basinger, M. Carlson, P. Hermanson, N. Kovacevic, M. A. McGill, et al. Assessing the Efficiency of RNA Interference for Maize Functional Genomics Plant Physiology, April 1, 2007; 143(4): 1441 - 1451. [Abstract] [Full Text] [PDF]