Isolation of the AP2/ERF transcription factor CaERF14 in pepper and functional characterization under salinity and dehydration stress.

Ethylene-responsive factors (ERF) are typically considered to play diverse roles in the plant's response to biotic and abiotic stresses. In this study, an ERF gene, CaERF14 was isolated from the pepper transcriptome database. The gene is 1,572 bp in length, containing an open reading frame (ORF) of 849 bp, which encodes a putative polypeptide of 283 amino acids with a theoretical molecular weight of 31.75 kDa. At the N-terminal, there is a conserved sequence of CMX-1 specific to the Xa subfamily of the ERF family. CaERF14 is located in the nucleus and part of the cell membrane, interacting with the GCC-box to regulate the expression of downstream related genes. Results from the expression profile show that CaERF14 has a higher expression level in parts of the floral and stem. Additionally, this gene can not only respond to the drought, NaCl, and Ralstonia solanacearum, but also be induced by signaling molecules (ABA, MeJA, Ethephon, SA, and auxins). Furthermore, the CaERF14 derived from peppers was transformed into the model plant tobacco. Regardless of the NaCl, mannitol, or soil drought stress tested for seed germination or seedling growth in in vitro or in vivo culture, this gene exhibits salt and drought tolerance function. These results suggest that CaERF14 is involved in the regulation of defense response to salinity and dehydration stress.