E2F/DP protein family in beans: Identification, evolution and expression analysis within the genome

E2F/DP is a transcription factor family that is essential for cell cycle control. The chromosomal distribution, gene structure/motif analysis, miRNA analysis and phylogenetic/orthologous relationships of PvE2F/DP family members have been assessed in this first known study of Phaseolus vulgaris (common bean). In this study, seven E2F/DP genes were identified in P. vulgaris genome and were classified into three subfamilies (PvE2F, PvDEL and PvDP) based on phylogenetic analyses. Five typical and two atypical conserved PvE2F/DP protein motifs, ranging in length from 6 to 50 amino acid residues, were found. In addition, three segmentally duplicated gene pairs were identified between PvE2F/DP subfamilies, which were thought to contribute to the expansion of E2F/DP genes. Several stress response related cis-acting elements were also identified in PvE2F/DP gene promotor regions suggesting the possible roles of PvE2F/DPs in response to salt stress. The effects of salt stress on protein content, catalase enzyme activity and mRNA levels of PvE2F/DP genes were evaluated in two P. vulgaris cultivars, namely ‘Elkoca-05′ and ‘Serra’ which are known to have different adaptation capacities against salt stress. Accordingly, the increases on these experimental parameters were found to be more pronounced in ‘Serra’, which is known to be more salt tolerant than ‘Elkoca-05′. The results of this study showed that PvE2F/DP genes might play an important role in response to salt stress and could be targeted in future studies for their potential to create transgenic common bean lines resistant to salt stress conditions.