ZmTIFY16, a novel maize TIFY transcription factor gene, promotes root growth and development and enhances drought and salt tolerance in Arabidopsis and Zea mays

The TIFY (a conserved core motif TIF[F/Y]XG) protein is a plant-specific transcription factor that regulates various plant growth/development and stress-related processes. Although many TIFY proteins have been reported in Arabidopsis thaliana, rice (Oryza sativa L.), and other plants, few studies have investigated the role of TIFY proteins in maize (Zea mays L.). In this study, we cloned and performed a preliminary structural and functional analysis of ZmTIFY16, a transcription factor gene that we previously identified in the genome of maize. This gene showed high expression in young and mature leaves and was strongly induced by low temperature (4oC), dehydration, drought, salt, and abscisic acid. Its heterologous expression in Arabidopsis markedly improved drought and salt tolerance, increased chlorophyll and proline contents, enhanced superoxide dismutase activity, and decreased malondialdehyde content. Moreover, ZmTIFY16 interacted with ZmMYC2, an essential regulator of the jasmonic acid signaling pathway, promoted root growth, and improved salt tolerance in overexpressing maize lines. The results suggest that ZmTIFY16 may be critical for regulating maize growth and abiotic stress responses. ZmTIFY16 may be a novel candidate gene for promoting root growth and development and regulating drought and salt tolerance in maize.