Identification of the ERF gene family in Aeluropus littoralis halophyte plant and analysis of their expression pattern in response to salt stress

Salt stress is one of the abiotic stresses limiting plant growth and development. The ethylene response factor (ERF) is one of the transcription factor family that involved in plant development and responses to biotic and abiotic stresses. Regarding to importance role of genes belonging to ERF gene family in plant responses to salt stress, identification of these genes in the Aeluropus littoralis, halophyte plant, was considered in this study. In total, 36 non-redundant ERF genes were identified in A. littoralis genome. The phylogenetic tree classified the AlERF gene family into six distinct groups (B1 to B6) based on hemology with the Araboidopsis thaliana. Gene structure analysis revealed that AlERF genes contained zero to two introns. Domain search and conserved motif analyses in AlERF protein sequences determined that 2 motifs (1 and 2) out of the identified 10 motifs participate in the AP2/ERF domain structure. Based on transcriptome data and heatmap diagram, AlERF6.3 gene was expressed more in root tissue under salinity stress, and the least expression level was observed in AlERF6.7 gene in leaf tissue under recovery conditions. The different expression patterns of genes in leaf and root tissues under salt stress suggested different regulatory mechanisms in the gene expression. The results of this study, as the first report on the ERF gene family in A. littoralis, provides basic information for further studies of the functional characteristics of AlERF genes.