Submitted to: Functional and Integrative Genomics
Publication Type: Peer reviewed journal
Publication Acceptance Date: 1/30/2006
Publication Date: 1/30/2006
Citation: Bernardo, A., Bai, G., Guo, P., Xiao, K., Guenzi, A., Ayoubi, P. Fusarium graminearum - induced differential gene expression between fusarium head blight-resistant and susceptible wheat cultivars. Functional and Integrative Genomics 7:69-77. Interpretive Summary: Wheat Fusarium head blight (FHB), caused by the fungus called Fusarium graminearum Schw., is an important wheat disease in the U.S.A. In order to understand the mechanisms of wheat resistance to FHB, a study on genome-wide gene expression was conducted to compare the responses of resistant and susceptible wheat cultivars to FHB infection. The gene expression patterns of FHB-resistant cultivar Ning 7840 and susceptible cultivar Clark were investigated during a period of 72 hours after the plants were infected by F. graminearum. Using new gene chip technology, we identified 44 genes that were most likely involved in plant responses to the fungal infection. Defense responses to the fungal infection occurred during early fungal infection stage (about 3 to 12 hours after fungal infection) in Ning 7840. Three genes with unknown function that were highly expressed in cv. Ning 7840 might play an important role in enhancing FHB resistance.
Technical Abstract: Fusarium head blight (FHB), primarily caused by Fusarium graminearum Schw., is a destructive disease of wheat (Triticum aestivum L.). Although several genes related to FHB resistance have been reported, global analysis of gene expression in response to FHB infection remains to be explored. The expression patterns of transcriptomes from wheat spikes of FHB-resistant cultivar Ning 7840 and susceptible cultivar Clark were monitored during a period of 72 hours after inoculation (hai) with F. graminearum. Microarray analysis, coupled with suppression subtractive hybridization technique, identified 79 significantly differentially expressed genes between cv. Ning 7840 and cv. Clark. More differentially expressed genes were identified from susceptible libraries than from resistance libraries. The up-regulation of defense-related genes in Ning 7840 relative to cultivar Clark occurred during early fungal stress (3-12 hai). Peak of expression of genes putatively involved in metabolism, photosynthesis and transcription in Ning 7840 was at 12 hai. Among other coordinately differentially expressed genes were two genes with unknown function that were up-regulated in cv. Ning 7840 at most time points investigated and might play an important role in enhancing FHB resistance.