Protein expression and fine interaction mechanism of banana MuMADS1 and MaOFP1

Abstract

MuMADS1 is an AGAMOUS (AG)-like MADS-box gene previously isolated from banana fruits. Previous investigation demonstrated that the K-domain of MuMADS1 interacts with MaOFP1. However, the expression characteristics of MuMADS1 and MaOFP1 proteins in banana fruits and their fine interaction mechanism need to be further investigated. In the present study, the expression characteristics of MuMADS1 and MaOFP1 proteins during banana fruits development and ripening process was investigated by Western blot. The interaction of MuMADS1 and MaOFP1 was demonstrated again by Pull down. The fine interaction mechanism of K-domain of MuMADS1 interacting with the ovate-domain and non-ovate-domain of MaOFP1 was further investigated by yeast two hybrid (Y2H) and bimolecular fluorescence complementation (BiFC) assay. The result indicated that MuMADS1 was differentially expressed during Baxi (BX) and Fenjiao (FJ) fruits development and ripening process. With the progress of banana fruit development, the expression level gradually increased and reached the peak at 0 DPH, and then gradually decreased. The expression level of MaOFP1 during BX and FJ fruits development and ripening process was significantly lower than MuMADS1. Moreover, the expression level of MaOFP1 in FJ was higher than in BX. The K-domain of MuMADS1 interacted with the ovate-domain of MaOFP1. These results laid the foundation for deeply understanding the role of MuMADS1 and MaOFP1 in banana fruits and provide gene resources for banana fruit ripening regulation.

Keywords

• banana (musa acuminata)
• mumads1
• maofp1
• protein expression
• interaction