Acts as a transcriptional activator. Binds to the GCC-box pathogenesis-related promoter element. Involved in the regulation of gene expression by stress factors and by components of stress signal transduction pathways. Ubiquitously expressed, mostly in flowers and rosettes after ethylene treatment. Induced by Pseudomonas syringae tomato (both virulent and avirulent avrRpt2 strains), independently of PAD4. Also induced by methyl jasmonate (MeJA) independently of JAR1. Ethylene induction is completely dependent on a functional ETHYLENE-INSENSITIVE2 (EIN2), whereas induction by wounding does not need EIN2. Induction by salicylic acid (SA) seems to be independent of PAD4 and NPR1. Transcripts accumulate strongly in cycloheximide-treated plants, a protein synthesis inhibitor. Seems to not be influenced by exogenous abscisic acid (ABA), cold, heat, NaCl or drought stress. The AP2/ERF domain binds specifically to the 5'-GCCGCC-3' motif. The affinity of this binding is higher if the seventh amino-acid of this domain is basic (By similarity). Belongs to the AP2/ERF transcription factor family. ERF subfamily. Two different genes At3g23240 and At4g17500 were assigned the same gene name ERF1. It is uncertain whether Met-1 or Met-3 is the initiator.