An ethylene-responsive transcription co-activator (MBF) acts on ethylene-responsive transcription factors (ERFs), which positively controls the expression of ethylene-responsive plant genes. A plant is transformed by the gene of the co-activator, and a promoter that may increase or decrease responsiveness to ethylene depending on its alignment. A method for controlling the responsiveness of plants to ethylene transforms a plant comprising an ERF-dependent gene, which positively control the expression of ethylene responsive genes of plants. This transcription co-activator gene is applied to control ethylene response of plants.