An Arabidopsis NAC domain transcriptional activator VND7 negatively regulates VNI2 expression

• Published in: Plant Biotechnology Vol. 38; no. 4; pp. 415 - 420
• Main Authors: Ailizati, Aili, Nagahage, Isura Sumeda Priyadarshana, Miyagi, Atsuko, Ishikawa, Toshiki, Kawai-Yamada, Maki, Demura, Taku, Yamaguchi, Masatoshi
• Format: Journal Article
• Language: English
• Published: Japan Japanese Society for Plant Biotechnology 25.12.2021; Japan Science and Technology Agency; Japanese Society for Plant Cell and Molecular Biology
• Subjects: Arabidopsis thaliana; Differentiation; Gene deletion; NAC domain protein; Original Paper; Proteins; Transcription activation; Transcription factor; Transcription factors; Transient assay; Xylem; Xylem vessel formation; Arabidopsis thaliana; transcription factor; transient assay; NAC domain protein; xylem vessel formation
• ISSN: 1342-4580; 1347-6114; 1347-6114
• DOI: 10.5511/plantbiotechnology.21.1013a

A NAC domain transcription factor, VND-INTERACTING2 (VNI2) is originally isolated as an interacting protein with another NAC domain transcription factor, VASCULAR-RELATED NAC-DOMAIN7 (VND7), a master regulator of xylem vessel element differentiation. VND7 directly or indirectly induces expression of a number of genes associated with xylem vessel element differentiation, while VNI2 inhibits the transcriptional activation activities of VND7 by forming a protein complex. VNI2 is expressed at an earlier stage of xylem vessel element differentiation than VND7. Here, to investigate whether VND7 also affects VNI2, a transient expression assay was performed. We demonstrated that VND7 downregulated VNI2 expression. Other transcription factors involved in xylem vessel formation did not show the negative regulation of VNI2 expression. Rather, MYB83, a downstream target of VND7, upregulated VNI2 expression. By using the deletion series of the VNI2 promoter, a 400 bp region was identified as being responsible for downregulation by VND7. These data suggested that VND7 and VNI2 mutually regulate each other, and VNI2 expression is both positively and negatively regulated in the transcriptional cascade.