Transcriptional activator activated by proteolytic cleavage through regulated intramembrane proteolysis (RIP) (By similarity). Transcripition activator associated with the induction of genes related to flavonoid biosynthesis and required for the accumulation of anthocyanins in response to high light stress (PubMed:19887540). Plays a role in the regulation of 20S and 26S proteasomes in response to high light stress (PubMed:21889048). Localized primarily in plasma membrane or endoplasmic reticulum membrane as dormant form and, upon specific stress or signal, is processed into a transcriptionally active and nuclear form after a proteolytic cleavage through regulated intramembrane proteolysis (RIP). Expressed in root meristem (Ref.1). Expressed in roots, rosette leaves, cauline leaves, shoot apex, stems and flowers (PubMed:17158162). By exposure to high light (PubMed:19887540). Induced by heat and methyl methanesulfonate (MMS) treatment (PubMed:17158162). The NAC domain includes a DNA binding domain and a dimerization domain. No visible phenotype under normal growth conditions.