P0173
Unraveling Iron Homeostasis of Maize Using Quantitative Genetic and Transcriptomic Approaches
Unraveling Iron Homeostasis of Maize Using Quantitative Genetic and Transcriptomic Approaches
Date: Monday, January 14, 2013
Room: Grand Exhibit Hall
Iron (Fe) deficiency caused by high pH is a serious problem for plants growing on calcareous soils. The severe symptoms of low Fe availability are leaf chlorosis, growth retardation, and reductions of yield and nutritive quality levels. The objectives of this study were to (i) detect quantitative trait loci (QTL) for Fe homeostasis in a segregating population of maize, (ii) detect differently expressed genes in the corresponding
parental inbreds RNA-Seq that colocalize with QTLs, and (iii) quantify the expression of these genes in the segregating population using qRT-PCR in order to identify regulatory loci by eQTL mapping. Various morphologic traits were recorded for 85 intermated recombinant inbred lines of the IBM population growing in a hydroponic system with two different Fe treatments. Transcript analyses were carried out on the
parental inbreds B73 and Mo17 using different complementary analyses pipelines. The analyses of the traits recorded at two Fe concentrations revealed a total number of 47 and 39 QTLs, where 31 and 20 genes evaluated from the RNA-Seq analyses colocalized with the QTL intervals for two Fe treatments, respectively. An eQTL mapping revealed for several genes from the methionine cycle a trans-regulation by a locus on chromosome 8 and for several genes involved in phytosiderophore synthesis a trans eQTL on chromosome 1. The present results provide new candidate genes and regulatory loci for Fe homeostasis and the possibility of improving Fe efficiency of maize by marker assisted selection.
parental inbreds RNA-Seq that colocalize with QTLs, and (iii) quantify the expression of these genes in the segregating population using qRT-PCR in order to identify regulatory loci by eQTL mapping. Various morphologic traits were recorded for 85 intermated recombinant inbred lines of the IBM population growing in a hydroponic system with two different Fe treatments. Transcript analyses were carried out on the
parental inbreds B73 and Mo17 using different complementary analyses pipelines. The analyses of the traits recorded at two Fe concentrations revealed a total number of 47 and 39 QTLs, where 31 and 20 genes evaluated from the RNA-Seq analyses colocalized with the QTL intervals for two Fe treatments, respectively. An eQTL mapping revealed for several genes from the methionine cycle a trans-regulation by a locus on chromosome 8 and for several genes involved in phytosiderophore synthesis a trans eQTL on chromosome 1. The present results provide new candidate genes and regulatory loci for Fe homeostasis and the possibility of improving Fe efficiency of maize by marker assisted selection.