A broad characterization of the transcriptional profile of the compatible tomato response to the plant parasitic root knot nematode Meloidogyne java']javanica

The root knot nematode Meloidogyne javanicaa plant parasite that is an agricultural pest, establishes and maintains a permanent feeding site within plant roots. In order to gain a broad view of gene expression in nematode feeding sites during the compatible response of tomato to root knot nematodes, we used the tomato spotted microarray chip, followed by real-time reverse transcription polymerase chain reaction (RT-PCR) validation. Cluster analysis and determination of the amplitude of gene expression suggested that the plant response at 5 days post-inoculation was not as vigorous as that at 10 days post-inoculation. In addition, by filtering the data for genes that were significantly up- or down-regulated during the interaction, we identified both the quantitative and qualitative differences between the two time points. Our microarray experiments demonstrated significant changes in the steady-state levels of transcripts of several functional categories, including pathogenesis-related genes, hormone-associated genes and development-associated transcription factors.