Protein changes associated with sugar beet resistance to Fusarium oxysporum.

Authors: Larson, Rebecca; Hill, Amy; Nunez, Alberto

Submitted to: American Society of Sugarbeet Technologists
Publication Type: Abstract Only
Publication Acceptance Date: 12/4/2006
Publication Date: N/A
Citation: N/A

Interpretive Summary: Fusarium oxysporum is serious threat to sugar beet production worldwide. Although certain sugar beet lines appear to have resistance against F. oxysporum, little is understood about the basis for that resistance. Examination of F. oxysporum-induced protein changes in the sugar beet will serve two purposes: to identify candidate genes for use in marker-assisted selection and to elucidate mechanisms responsible for resistance. Sugar beet genotype C1200.XH024, with resistance to F. oxysporum isolate F-19, was analyzed at 2- and 5-days post pathogen challenge and compared to mock-inoculated beets. These times correlate with initial infection and vascular tissue penetration, respectively. A total of approximately 950 proteins were reproducibly detected in the sugar beet leaf and root protein extracts using multidimensional liquid chromatography. One hundred twenty-one proteins were differentially expressed during resistance to F-19. Fourteen were only expressed during initial infection, forty-three once the vascular system was penetrated and forty-nine were expressed at both points. Fifteen proteins were repressed in F-19 challenged tissue in comparison to the mock inoculated control. Seventy protein peaks were analyzed by matrix-assisted laser desorption ionization time-of-flight mass spectrometry, the remaining protein peaks were below the level of detection. This analysis lead to the identification of proteins associated with salicylic acid-dependent resistance, the oxidative burst, signal transduction, photosynthesis, respiration and gene expression and regulation.

Technical Abstract: Fusarium oxysporum is serious threat to sugar beet production worldwide. Although certain sugar beet lines appear to have resistance against F. oxysporum, little is understood about the basis for that resistance. Examination of F. oxysporum-induced protein changes in the sugar beet will serve two purposes: to identify candidate genes for use in marker-assisted selection and to elucidate mechanisms responsible for resistance. Sugar beet genotype C1200.XH024, with resistance to F. oxysporum isolate F-19, was analyzed at 2- and 5-days post pathogen challenge and compared to mock-inoculated beets. These times correlate with initial infection and vascular tissue penetration, respectively. A total of approximately 950 proteins were reproducibly detected in the sugar beet leaf and root protein extracts using multidimensional liquid chromatography. One hundred twenty-one proteins were differentially expressed during resistance to F-19. Fourteen were only expressed during initial infection, forty-three once the vascular system was penetrated and forty-nine were expressed at both points. Fifteen proteins were repressed in F-19 challenged tissue in comparison to the mock inoculated control. Seventy protein peaks were analyzed by matrix-assisted laser desorption ionization time-of-flight mass spectrometry, the remaining protein peaks were below the level of detection. This analysis lead to the identification of proteins associated with salicylic acid-dependent resistance, the oxidative burst, signal transduction, photosynthesis, respiration and gene expression and regulation.