Functional roles of two 14-3-3s in response to salt stress in common bean

14-3-3 proteins are involved in the regulation of multiple stress signal transduction in plants. Common bean ( Phaseolus vulgaris L.) is an important crop legume worldwide, but soil salinity is generally a major cause of its productivity loss. Previously, we identified and characterized 9 14-3-3s (PvGF14s) in common bean. In this study, the 9 PvGF14s were applied to phylogenetic analysis with 13 14-3-3s from other plant species, which have been experimentally validated to regulate plant response to various stresses. Consequently, 3 PvGF14s (PvGF14a, PvGF14g and PvGF14h) were clustered together with 8 stress-responsive 14-3-3s. Subsequently, PvGF14a and PvGF14g were chosen to investigate their roles in response to salt stress in Arabidopsis . It was observed that over-expression of PvGF14a and PvGF14g not only reduced seed germination rate and fresh weight of seedlings under salt stress, but also led to pale-white appearance of seedlings, suggesting that PvGF14a and PvGF14g might negatively regulate salt tolerance. Furthermore, protein–protein interaction assays indicated that PvGF14g and PvGF14a can interact with PvSOS2, the most closely related homolog of AtSOS2 (salt tolerance-related kinase in Arabidopsis ) in common bean, implying that PvGF14a and PvGF14g are possibly implicated in the regulation of salt tolerance via interacting with PvSOS2. Additionally, a MYB protein (MYB173) responsive to salt stress also showed interaction with PvGF14g and PvGF14a. Thus, the findings provided a preliminary insight into the functional roles of PvGF14g and PvGF14a in the regulation of salt tolerance.