Quantitative Proteomic Analysis of Bean Plants Infected by a Virulent and Avirulent Obligate Rust Fungus

Authors: LEE, JOOHYUN - KOREA; Campbell, Kimberly; Scheffler, Brian; FENG, JIAN - JOHNS HOPKINS UNIVERSITY; NAIMAN, DANIEL - JOHNS HOPKINS UNIVERSITY; Garrett, Wesley; THIBIVILLIERS, SANDRA - UNIVERSITY OF MISSOURI; STACEY, GARY - UNIVERSITY OF MISSOURI; Tucker, Mark; Pastor Corrales, Marcial; Cooper, Bret

Submitted to: Molecular and Cellular Proteomics
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/27/2008
Publication Date: 8/27/2008
Citation: Lee, J., Campbell, K., Scheffler, B.E., Feng, J., Naiman, D.Q., Garrett, W.M., Thibivilliers, S., Stacey, G., Tucker, M.L., Pastor Corrales, M.A., Cooper, B. 2008. Quantitative Proteomic Analysis of Bean Plants Infected by a Virulent and Avirulent Obligate Rust Fungus. Molecular and Cellular Proteomics. 8:19-31.

Interpretive Summary: Little is known about the proteins that make up leaves of bean plants. Discovery of proteins that are important for disease resistance to pathogens may help improve bean cultivars through breeding or transgenic technology. Mass spectrometry was used to identify proteins and measure the amounts of proteins in plants infected with a fungus that causes rust disease. Comparison between plants that are naturally resistant and plants naturally susceptible revealed a set of proteins that contribute to the resistance response. A separate set of proteins was found to help the fungus survive in susceptible plants. These results have helped identify disease resistance proteins that could eventually be used to protect susceptible plants. These data are most likely to influence scientists at universities, government agencies and companies who are searching for new genes to fight rust diseases.

Technical Abstract: Plants appear to have two types of active defenses, a broad-spectrum basal system and a system controlled by R-genes giving stronger resistance to some pathogens that break the basal defense. However, the existence of separate systems is unknown. Therefore, we analyzed more than 3,000 proteins in the dry bean crop plant Phaseolus vulgaris. By statistically comparing the amounts of proteins detected in one plant variety that is susceptible or resistant to infection, depending on the strains of a rust fungus introduced, we generated a proteomics resource defining basal and R-gene mediated plant defenses. The data reveal that some basal defense proteins are potential regulators of a strong defense weakened by the fungus and that the R-gene modulates proteins similar to those in the basal system. The results satisfy a model whereby R-genes repair disabled basal defenses to reinstate resistance rather than amplify them beyond an effective resistance threshold.