FIT (Fer-like iron deficiency-induced transcription factor) in plant iron homeostasis: genome-wide identification and bioinformatics analyses

FIT (Fer-like iron deficiency-induced transcription factor) is one of the key regulators in uptake of iron (Fe) for plants. In this study, FIT genes from 10 plant species were identified at genome-wide scale and analyzed by computational tools. Our analyses showed that subcellular localizations of all FITs were in nucleus and FITs were generally acidic proteins. While a clear monocot–dicot divergence was observed, exon numbers were found as three and four for monocots and dicots, respectively. Arg and Leu were established as most repetitive amino acid residues in conserved regions of all FITs. All FITs had different shape and pocket numbers along with different secondary and tertiary structures despite they contained same domain structure as PF00010 (helix-loop-helix DNA-binding domain). We observed that FIT is an important target of several biological processes and a component of various metabolic pathways regulating root development and stress responses on exposure to various environmental stressors. Moreover, FITs seem to be located in heterochromatic area of chromosome and its transcription may also be upregulated on the exposure of stressors. The FITs were established to interact with Pi and Cu uptake machinery, other than iron acquisition, under Pi and Cu deficiency. Consequently, FITs can be proposed to take part in different and specific metabolic pathways together with Fe acquisition. The miRNA analyses showed that miRNAs targeting FITs take part in abiotic and biotic stress metabolism together with Pi uptake mechanism. Lastly, involvement of FIT in abiotic stress response was stimulated by phytohormones such as ABA and ethylene. © 2019, Society for Plant Biochemistry and Biotechnology