|Luo, M - UNIV. OF GA, TIFTON,GA|
|He, G - TUSKEGEE UNIV,TUSKEGEE,AL|
Submitted to: American Phytopathological Society Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: June 1, 2005
Publication Date: July 25, 2005
Citation: Guo, B.Z., Luo, M., Dang, P., He, G., Holbrook, Jr., C.C. 2005. Differentially expressed genes in responses to late leaf spot disease caused by Cercosporidium personatum in peanut using microarray analysis. Phytopathology. 95:S37-S38. Technical Abstract: Late leaf spot disease caused by Cercosporidium personatum is one of the most destructive foliar diseases of peanut worldwide. This research was to identify resistance genes in response to leaf spot disease using miccroarray and real-time PCR. To identify transcripts involved in disease resistance, we studied the gene expression profiles in two peanut genotypes, resistant or susceptible to leaf spot disease, using cDNA microarray containing 384 unigenes selected from two EST (expressed sequenced tag) cDNA libraries challenged by abiotic and biotic stresses. A total of 112 spots representing 56 genes in several functional categories were detected as up-regulated genes (Log2 ratio>1). Seventeen of the top 20 genes, each matching gene with known function in GenBank, were selected for validation of their expression levels using real-time PCR. These two peanut genotypes were also used to study the functional analysis of these genes and possible link of these genes to the disease resistance trait. Microarray technology and real-time PCR were used for comparison of gene expression. The selected genes identified by microarray analysis were validated by real-time PCR. These genes were more highly expressed in the resistant genotype as a result of response to the challenge of (C. personatum) than in the susceptible genotype. Further investigations are needed to characterize each of these genes in disease resistance. Gene probes could then be developed for application in breeding programs for marker-assisted selection.