Use of MACE technology to identify positional and expressional candidate genes for resistance to Didymella pinodes in pea

Abstract

MACE (Massive Analysis of cDNA Ends) allows ultra-deep transcription profiling without PCR introduced bias by combining second-generation sequencing and the TrueQuant technology. In MACE each cDNA molecule is represented by one sequence (the tag) of 94 bp, originating from a region around 100–500 bp from the 3’ (poly-A) end of the transcript. High-throughput sequencing of tags provides numerical gene expression values and allows the identification of SNPs and INDELS from the 3’ends of the genes. In the frame of “LEGATO” project, we are using MACE to identify positional and expressional candidate genes for resistance to Didymella pinodes in pea. MACE has been used to perform a detailed transcriptomic study to identify genes differentially expressed in a resistant reaction (accession P665) compared to a susceptible one (cv. Mes sire). The resulting sequences will be used to identify SNPs between P665 and Messire for these differentially expressed genes. These SNPs will be further genotyped in the RIL population P665 x Messire in a high throughput way by sequencing MACE libraries from 94 RIL families. This will allow the mapping of these differentially expressed genes in the P665 x Messire genetic map and the study of their possible co-localization with the QTLs associated with resistance to D. pinodes that have been already identified in this population.