Gene expression profiling of resistant and susceptible soybean lines infected with soybean cyst nematode.

Soybean cyst nematode (SCN) is the most devastating pathogen of soybean. Information about the molecular basis of soybean-SCN interactions is needed to assist future development of effective management tools against this pathogen. Toward this end, soybean transcript abundance was measured using the Affymetrix Soybean Genome Array in a susceptible and a resistant reaction of soybean to SCN infection. Two genetically related soybean sister lines TN02-226 and TN02-275, which are resistant and susceptible, respectively, to the SCN race 2 infection were utilized in these experiments. Pairwise comparisons followed by false discovery rate analysis indicated that the expression levels of 162 transcripts changed significantly in the resistant line, of which 84 increased while 78 decreased. However, in the susceptible line, 1,694 transcripts changed significantly, of which 674 increased while 1,020 decreased. Comparative analyses of these transcripts indicated that a total of 51 transcripts were in common between resistance and susceptible responses. In this set, 42 transcripts increased in the resistant line, but decreased in the susceptible line. Quantitative real-time reverse-transcription polymerase chain reaction confirmed the results of microarray analysis. Of the transcripts to which a function could be assigned, genes were associated with metabolism, cell wall modification, signal transduction, transcription, and defense. Microarray analyses examining two genetically related soybean lines against the same SCN population provided additional insights into the specific changes in gene expression of a susceptible and a resistant reaction beneficial for identification of genes involved in defense.