Genome-wide characterization, identification, and isolation of auxin response factor (ARF) gene family in maize

Auxin response factors (ARFs) are key regulators of numerous aspects of plant growth and development through mediating auxin signaling. In this study, we conducted a comprehensive genome-wide analysis of ZmARFs to identify and validate all auxin response factor genes in maize. These ZmARF genes were categorized into four distinct groups (I-IV) based on phylogenetic analysis, revealing seven sister pairs. We presented detailed information on gene sequences, structures, chromosome locations, and conserved motifs of ZmARFs. Through transient expression assays, we identified transcriptional activators or repressors among ZmARFs. Notably, our study demonstrated, for the first time, that ZmARF3 acts as a positive regulator of adventitious roots development in maize. This study not only provides basic insights into the maize ARF gene family but also sheds light on the specific functions of ZmARF3, paving the way for a more precise understanding of ZmARFs' roles in plant growth and development in maize.