Auxin response factors (ARFs) are transcriptional factors that bind specifically to the DNA sequence 5'-TGTCTC-3' found in the auxin-responsive promoter elements (AuxREs). Could act as transcriptional activator or repressor. Formation of heterodimers with Aux/IAA proteins may alter their ability to modulate early auxin response genes expression. Involved in ethylene responses. Regulates lateral root formation through direct regulation of LBD16 and/or LBD29 (PubMed:29184030). Functionally redundant with ARF7 (PubMed:29184030). Involved in cellular dedifferentiation during callus formation on callus-inducing medium (CIM) and in an ATXR2-dependent manner (PubMed:29184030). Homodimers and heterodimers (PubMed:9342315). Interacts with the auxin-responsive protein IAA1 (PubMed:9342315). Binds to JMJ30 (PubMed:29923261). Binds to ATXR2 in the nucleus (PubMed:29184030). By auxin and ethylene. Interactions between auxin response factors (ARFs) and Aux/IAA proteins occur through their C-terminal dimerization domains III and IV. The arf7-1 arf19-2 double mutant is defective in callus formation. Belongs to the ARF family.