1a.Objectives (from AD-416):
Fine mapping, metabolomics and transcriptomics of genes for soybean aphid resistance.
1b.Approach (from AD-416):
Recombinant inbred line (RIL) populations and near isogenic lines (NILs) will be used for conducting the fine mapping, metabolomics, transcriptomics and proteomics studies with help from collaborators.
The Collaborator at University of Missouri, conducted real time PCR experiments to amplify candidate genes predicted from the RNA sequence data of near isogenic lines (NILs) of the Rag2 for soybean aphid resistance. The RNA-sequence and proteomic data on these NILs were generated from a previous project by this collaborator. The real time PCR data was found to correlate well with the global transcriptome results obtained by RNAseq analysis.
The proteomic data of the 4 time points (8, 16, 24, 48 hrs after soybean aphid infestation) was integrated and analyzed to identify proteins differentially regulated in response to aphid infestation of the NILs of the Rag2 gene. These proteins were then compared to the RNA-seq data. Over 150 proteins were found to be regulated at the various time points tested. Most exciting, we identified 50-100 proteins at each time point that were specifically regulated either in Rag2 positive or Rag2 negative lines. That is, these proteins are those that are specifically impacted by the presence of the Rag2 resistance allele. We are now correlating these protein results with those obtained from transcriptional profiling of these same NILs. We are also correlating the location of the encoded proteins with the known location of the Rag2 gene. The net result of these analyses, when completed, will be a thorough molecular view defining the response of the soybean plant to aphid infection and, specifically, how this response is affected by the presence of the Rag2 resistance gene. A manuscript on the proteomics and transcriptomics data is in preparation.
This project relates to and expands on objective 2B (Genetic characterization and molecular mapping of aphid resistance genes) of the parent project.