Start Date: Jun 01, 2009
End Date: May 31, 2014
The experiments will utilize massively parallel sequencing technology performed on an Illumina GA2 platform to examine the “interactome” between S. sclerotiorum and pea over a time course during compatible (susceptible) and incompatible (partially resistant) interactions. The sequencing of cDNA tags has been demonstrated to be subject to less background noise than traditional hybridization-based (i.e. microarray) approaches. We will use an EST data set that we are currently analyzing to aid interpretation of sequence reads from the Illumina GA2 platform as well as public EST database resources of pea, closely related model species and the S. sclerotiorum genome sequence. Our cooperators at the Michigan State Research Technology Support Facility through collaborations also have access to a large number of pea ESTs that are not publicly available. The expression profiles and the difference between susceptible and partially resistant pea genotypes and the difference that occurs over time will be used to examine the expression of genes from host and pathogen during their interaction. This approach will allow us to identify and quantify pathogenicity genes expressed by S. sclerotiorum as well as genes participating in the resistance pathway in pea. ESTs of interest will also be examined by analysis of gene ontology classes. Tissue will be collected from infected plants over a time-course after inoculation to capture the initial, sustained, and late gene expression changes associated with the interaction. It is expected that we will identify genes and pathways involved in the pathogenicity of S. sclerotiorum on pea and genes and signaling pathways involved in the partial resistance of pea to Sclerotinia. Additionally, by identifying genes involved in resistance we plan to develop genetic markers for marker assisted breeding of resistant pea lines.