Genome-wide Identification and Expression Pattern Analysis of the ERF Gene Subfamily in Nicotiana tabacum

Ethylene-responsive element binding factors (ERF transcription factors) family is widely involved in plant development, stress resistance and hormone response. Using bioinformatics methods, we have identified 121 ERF transcription factors that are located on 24 chromosomes irregularly in Nicotiana tabacum. This was followed by analyzing their chromosomal location, protein properties, phylogenetic relation, conserved domain structure, subcellular localization as well as tissue expression profile. Based on phylogenetic analysis these 121 members of the ERF family were classified into six groups, according to the classification of Arabidopsis thaliana. Genes from the same group have similar properties and the conserved domains show a high degree of conservation. The results of subcellular localization analysis indicate that most of the genes are located in the nucleus, while a small number of them are localized on the mitochondria and chloroplasts. Some genes of ERF transcript factors have high level expression in young roots, mature roots, leaves and stems. Also, genes from different groups have different expression profiles.