Ethylene-responsive factors (ERFs), within a subgroup of the AP2/ERF transcription factor family, are involved in diverse plant reactions to biotic or abiotic stresses. Here, we report that overexpression of an ERF gene from Bras-sica rapa ssp. pekinensis (BrERF4) led to improved toler-ance to salt and drought stresses in Arabidopsis. It also significantly affected the growth and development of transgenic plants. We detected that salt-induced expres-sions of a transcriptional repressor gene, AtERF4, and some Ser/Thr protein phosphatase2C genes, ABI1, ABI2 and AtPP2CA, were suppressed in BrERF4-overexpres-sing Arabidopsis plants. Furthermore, BrERF4 was in-duced by treatment with ethylene or methyljasmonate, but not by abscisic acid or NaCl in B. rapa. These results suggest that BrERF4 is activated through a network of different signaling pathways in response to salinity and drought.

Keywords: Brassica rapa (B. rapa), drought stress, ethylene-responsive factor (ERF), salt stress, transcriptional regulator