Gyeongsang National University Jinju, Kyongsang-namdo, Republic of Korea
Body of Abstract: ELONGATE HYPOCOTYL 5 (HY5) and constitutional PHOTOMORPHOGENIC 1 (COP1) regulate diverse plant growth and development responses and act as the master regulators. Earlier, we noticed approximately ~86 proteins interact with HY5 or COP1 in yeast. The VOZ1 (VASCULAR PLANT ONE-ZINC FINGER1) transcription factor is one of the interacting partners of HY5 and COP1 and is a key regulator of plant growth and development. Recently, it was found that VOZ1 is involved in plant growth and development, including stress response. However, the interaction of VOZ1 with other proteins and its function is unknown. Here, we revealed the interaction of VOZ1 with HY5 and COP1. We demonstrate that VOZ1, HY5, and COP1 physically interact using yeast-two hybrid assay and in planta BiFC (bimolecular fluorescence complementation) assays. Additionally, we confirm the subcellular localization of 35S::GFP-VOZ1, 35S::GFP-HY5, and 35S::GFP-COP1 to the nucleus. In Arabidopsis, VOZ1 is known to have a similar function to VOZ2 (VASCULAR PLANT ONE-ZINC FINGER2). Moreover, to investigate the function of the VOZ1 transcription factor, we made 35S::VOZ1-SRDX lines and observed that 35S::VOZ1-SRDXs are hypersensitive to salt stress as compared to wild type. Furthermore, we observed interactions between MAP kinases (mitogen-activated protein kinases) as key regulators of salt stress with VOZ1, suggesting that VOZ1 regulates stress responses by binding with these regulatory proteins. In summary, our work reveals that VOZ1 is a key target of HY5, COP1, and MAP kinases and functions as a positive regulator under salt stress.