Plant Physiology Preview
Published on March 18, 2005; 10.1104/pp.104.057257
Received November 26, 2004
Returned for revision January 30, 2005
Accepted January 30, 2005
RNA Interference of Soybean Isoflavone Synthase Genes Leads to Silencing in Tissues Distal to the Transformation Site and to Enhanced Susceptibility to Phytophthora sojae
Senthil Subramanian , Madge Y. Graham , Oliver Yu , and Terrence L. Graham *
Donald Danforth Plant Science Center, St. Louis, Missouri 63132
Department of Plant Pathology, Plant Molecular Biology and Biotechnology Program, Ohio State University and Ohio Agricultural Research and Development Center, Columbus, Ohio 43210
* Corresponding author; email: graham.1{at}osu.edu.
Isoflavones are thought to play diverse roles in plant-microbe interactions and are also potentially important to human nutrition and medicine. Isoflavone synthase (IFS) is a key enzyme for the formation of the isoflavones. Here, we examined the consequences of RNAi silencing of genes for this enzyme in soybean (Glycine max). Soybean cotyledon tissues were transformed with Agrobacterium rhizogenes carrying an RNAi silencing construct designed to silence expression of both copies of IFS genes. Approximately 50% of emerging roots were transformed with the RNAi construct, and most transformed roots exhibited >95% silencing of isoflavone accumulation. Silencing of IFS was also demonstrated throughout the entire cotyledon (in tissues distal to the transformation site) both by high-performance liquid chromatography analysis of isoflavones and by real-time reverse transcription-PCR. This distal silencing led to a nearly complete suppression of mRNA accumulation for both the IFS1 and IFS2 genes and of isoflavone accumulations induced by wounding or treatment with the cell wall glucan elicitor from Phytophthora sojae. Preformed isoflavone conjugates were not reduced in distal tissues, suggesting little turnover of these stored isoflavone pools. Distal silencing was established within just 5 d of transformation and was highly efficient for a 3- to 4-d period, after which it was no longer apparent in most experiments. Silencing of IFS was effective in at least two genotypes and led to enhanced susceptibility to P. sojae, disrupting both R gene-mediated resistance in roots and nonrace-specific resistance in cotyledon tissues. The soybean cotyledon system, already a model system for defense signal-response and cell-to-cell signaling, may provide a convenient and effective system for functional analysis of plant genes through gene silencing.
This article has been cited by other articles:
|
|
|
|
 
L. P. Manavalan, S. K. Guttikonda, L.-S. Phan Tran, and H. T. Nguyen
Physiological and Molecular Approaches to Improve Drought Resistance in Soybean
Plant Cell Physiol.,
July 1, 2009;
50(7):
1260 - 1276.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
E. G.W.M. Schijlen, C.H. R. de Vos, S. Martens, H. H. Jonker, F. M. Rosin, J. W. Molthoff, Y. M. Tikunov, G. C. Angenent, A. J. van Tunen, and A. G. Bovy
RNA Interference Silencing of Chalcone Synthase, the First Step in the Flavonoid Biosynthesis Pathway, Leads to Parthenocarpic Tomato Fruits
Plant Physiology,
July 1, 2007;
144(3):
1520 - 1530.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
B. H. Le, J. A. Wagmaister, T. Kawashima, A. Q. Bui, J. J. Harada, and R. B. Goldberg
Using Genomics to Study Legume Seed Development
Plant Physiology,
June 1, 2007;
144(2):
562 - 574.
[Full Text]
[PDF]
|
|
|
|
|
|
|
D. A. Samac and M. A. Graham
Recent Advances in Legume-Microbe Interactions: Recognition, Defense Response, and Symbiosis from a Genomic Perspective
Plant Physiology,
June 1, 2007;
144(2):
582 - 587.
[Full Text]
[PDF]
|
|
|
|
|
|
|
J. Zhang, S. Subramanian, Y. Zhang, and O. Yu
Flavone Synthases from Medicago truncatula Are Flavanone-2-Hydroxylases and Are Important for Nodulation
Plant Physiology,
June 1, 2007;
144(2):
741 - 751.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
N. Shimada, S. Sato, T. Akashi, Y. Nakamura, S. Tabata, S.-i. Ayabe, and T. Aoki
Genome-wide Analyses of the Structural Gene Families Involved in the Legume-specific 5-Deoxyisoflavonoid Biosynthesis of Lotus japonicus
DNA Res,
April 23, 2007;
(2007)
dsm004v1.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
S. A. Jackson, D. Rokhsar, G. Stacey, R. C. Shoemaker, J. Schmutz, and J. Grimwood
Toward a Reference Sequence of the Soybean Genome: A Multiagency Effort
Crop Sci.,
November 1, 2006;
46(Supplement_1):
S-55 - S-61.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
A. P. Wasson, F. I. Pellerone, and U. Mathesius
Silencing the Flavonoid Pathway in Medicago truncatula Inhibits Root Nodule Formation and Prevents Auxin Transport Regulation by Rhizobia
PLANT CELL,
July 1, 2006;
18(7):
1617 - 1629.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
M. Y. Graham
The Diphenylether Herbicide Lactofen Induces Cell Death and Expression of Defense-Related Genes in Soybean
Plant Physiology,
December 1, 2005;
139(4):
1784 - 1794.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
