Source: KANSAS STATE UNIV submitted to NRP
USE OF RNA INTERFERENCE FOR FUNGAL DISEASE RESISTANCE
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
COMPLETE
Funding Source
HATCH
Reporting Frequency
Annual
Accession No.
0201494
Grant No.
(N/A)
Cumulative Award Amt.
(N/A)
Proposal No.
(N/A)
Multistate No.
(N/A)
Project Start Date
Jul 1, 2004
Project End Date
Jun 30, 2006
Grant Year
(N/A)
Program Code
[(N/A)]- (N/A)
Recipient Organization
KANSAS STATE UNIV
(N/A)
MANHATTAN,KS 66506
Performing Department
PLANT BIOTECHNOLOGY CENTER
Non Technical Summary
Rice blast disease, in itself the most serious disease of rice, is an increasingly powerful model system for studying fungal plant diseases in general, due to the ease of molecular and genetic analyses and the availability of genome sequences for both Magnaporthe grisea and rice
Animal Health Component
50%
Research Effort Categories
Basic
50%
Applied
50%
Developmental
(N/A)
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
2011530108050%
2061530108050%
Knowledge Area
206 - Basic Plant Biology; 201 - Plant Genome, Genetics, and Genetic Mechanisms;

Subject Of Investigation
1530 - Rice;

Field Of Science
1080 - Genetics;
Goals / Objectives
(1) Test the efficacy of exogenously applied RNAi molecules to inhibit EGFP gene expression in fungus grown in axenic culture. (2) Test efficacy of dsRNAs produced in transgenic rice to interfere with fungal EGFP expression during infection. (3) Target essential fungal pathogenicity genes for RNAi interference and demonstrate disease control.
Project Methods
We propose to test a novel approach to controlling plant diseases using genetically engineered rice plants expressing RNA interference (RNAi) directed to specific fungal pathogen genes. RNAi refers to the introduction of homologous double-strand RNA (dsRNA) into a cell's cytoplasm to target a specific gene. A natural enzyme in cells, called Dicer, cuts this trigger dsRNA molecule into small interfering RNAs (siRNAs), approximately 22 nucleotides in length and containing 2 nucleotide overhangs at both 3' ends. The siRNAs interact with a RNA-Induced Silencing Complex, which binds and cleaves the homologous mRNA. dsRNA can cause gene silencing in a range of eukaryotic organisms, including fungi, insects, plants, and nematodes.

Progress 07/01/04 to 06/30/06

Outputs
Due to the intellectual property rights complete disclosure is not possible. A provisional patent was filed in March of 2005 and a utility patent filed early in 2006 is planned. Four separate genes have been selected for experimental proof of concept. Partial sequences of these genes were amplified from the respected species by PCR and sequenced for confirmation. RNAi vectors were developed based on these sequences. Two different plant-pathogen systems were evaluated and both in planta and in vitro assays have been performed with these vectors. With the current methodologies tested, all results were either negative or inconclusive.

Impacts
Current methods of pathogen fungal control include the use of natural disease resistant cultivars, crop rotation and other management practices and the use of chemical fungicides. For some fungal pathogens little genetic resistance exists and chemical fungicides are ineffective or cost prohibitive for the producer to deploy. Examples of these pathogens include Soybean Rust and Cereal (Wheat and Barley) Head Scab. For pathogens such as the rice blast fungus and various rusts, genetic resistance occurs but its effectiveness is limited because the pathogens "overcome" this resistance shortly after it is deployed in the field. The above fungal diseases have losses estimates in the millions. Our research has the potential to provide durable resistance.

Publications

  • No publications reported this period


Progress 01/01/05 to 12/31/05

Outputs
Due to the intellectual property rights complete disclosure is not possible at this time. A provisional patent was filed in March of 2005 and a utility patent should be filed early in 2006. Four separate genes have been isolated and currently are being evaluated for disease resistance. Research is being conducted on both in planta and in vitro assays.

Impacts
Current methods of pathogen fungal control include the use of natural disease resistant cultivars, crop rotation and other management practices and the use of chemical fungicides. For some fungal pathogens little genetic resistance exists and chemical fungicides are ineffective or cost prohibitive for the producer to deploy. Examples of these pathogens include Soybean Rust and Cereal (Wheat and Barley) Head Scab. For pathogens such as the rice blast fungus and various rusts, genetic resistance occurs but its effectiveness is limited because the pathogens overcome this resistance shortly after it is deployed in the field. The above fungal diseases have loss estimates in the millions. Our research has the potential to provide durable resistance.

Publications

  • No publications reported this period