Comparative transcriptomic analysis of iron deficiency response in roots of Oryza sativa and O. rufipogon

Iron (Fe) is an essential micronutrient for almost all organisms. However, Fe is frequently inaccessible to plants. To acquire insoluble Fe from soil, rice (Oryza sativa L.) plants employ a Combined Strategy, which is composed by all features of Strategy II, common to all Poaceae species, and some features of the Strategy I from non-Poaceae. To understand the evolution of Fe uptake mechanisms, we analyzed the root transcriptomic response to Fe deficiency in two species from the Oryza genus: O. sativa and its wild progenitor O. rufipogon. A total of 622 and 2,017 genes were found to be differentially expressed in O. sativa and O. rufipogon, respectively. Among the genes regulated in both species, we found the Fe transporters associated with Strategy I, such as IRT1, IRT2 and NRAMP1; and genes associated with Strategy II, such as YSL15 and IRO2. We analyzed the root transcriptomic response to Fe deficiency in two species from the Oryza genus: Oryza sativa (cv. Nipponbare) and Oryza rufipogon (BRA 00004909-8 accession from EMBRAPA). Plants were grown in lab conditions under control and Fe deficiency treatments up to three-leaf stage. Two biological replicates, each composed of roots from three plants, were collected after five days of treatment. Total RNA was extracted from roots and libraries were generated and sequenced at Fasteris® using HiSeq Illumina 2000 and single-end sequencing (50 bp).