NAC Transcription Factors in Woody Plants

NAC proteins are a family of plant-specific transcription factors (TFs) that are involved in the regulation of diverse biological processes, including stress tolerance, the formation and differentiation of vascular tissues and wood formation, the last of which is particularly important in trees. Evolutionary studies conducted on NAC proteins suggest a prominent role of these regulatory proteins in the adaptation and survival of plants to land habitats. The characterization of this family of TFs in trees is scarce, and the function of most of the family members remains unknown. However, current advances in sequencing technology, genomic analysis and expression studies from different woody plants have provided novel insights into the role of some of these TFs in trees. Recent research activity has mostly focused on the NAC proteins involved in processes related to improving plant biomass production, which is strongly affected by environmental conditions and has important ecological and economic implications. Studies performed in angiosperm and gymnosperm woody plants suggest that the regulatory network involved in stress responses and wood formation could be conserved.