eQTL mapping of the 12S globulin cruciferin gene PGCRURSE5 as a novel candidate associated with starch content in potato tubers
We prepared QTL map of tuber starch content in potato diploid population. Then, we examined expression level of enzyme ADP-glucose pyrophosphorylase (AGPase) taking part in starch biosynthesis (marker AGPaseS-a). Based on starch content and  AGPaseS-a expression, we constructed four bulks prepared from RNA isolated from tubers of F1 individuals H1 and H2 consisted of high TSC genotypes, bulks L1 and L2 were made of low TSC genotypes. Plants in bulks H1 and L1 strongly expressed AGPaseS-a, whereas those in bulks H2 and L2 exhibited low levels. Then we used RNA-seq technology for selection of genes displaying differential expression between RNA pools. For selected candidate genes we mapped expression QTL (e-QTL) and found eQTL of eAGPaseS-a and ePGRCRURSE5, were close to the corresponding loci of (AGPaseS-a) and the 12S globulin cruciferin gene (PGCRURSE5). We concluded that the cruciferin gene PGRCRURSE5 is a novel candidate involved in the regulation of starch content in potato tubers and suggests that cruciferin may be a novel PTST protein in potato tubers. Overall design: Examination of eQTL for candidate genes involved in starch accumulation in potato tubers.