FtbZIP85 Is Involved in the Accumulation of Proanthocyanidin by Regulating the Transcription of FtDFR in Tartary Buckwheat

Shuangshuang Liu; Jianmei Wang; Zhibin Liu; Yi Yang; Xiaoyi Li

doi:10.3390/cimb45040221

FtbZIP85 Is Involved in the Accumulation of Proanthocyanidin by Regulating the Transcription of FtDFR in Tartary Buckwheat

Curr Issues Mol Biol. 2023 Apr 13;45(4):3375-3390. doi: 10.3390/cimb45040221.

Authors

Shuangshuang Liu¹, Jianmei Wang¹, Zhibin Liu¹, Yi Yang¹, Xiaoyi Li¹

Affiliation

¹ Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu 610065, China.

Abstract

As a drought-tolerant crop, Tartary buckwheat survives under adverse environmental conditions, including drought stress. Proanthocyanidins (PAs) and anthocyanins are flavonoid compounds, and they participate in the regulation of resistance to both biotic and abiotic stresses by triggering genes' biosynthesis of flavonoids. In this study, a basic leucine zipper, basic leucine zipper 85 (FtbZIP85), which was predominantly expressed in seeds, was isolated from Tartary buckwheat. Our study shows that the expressions of FtDFR, FtbZIP85 and FtSnRK2.6 were tissue-specific and located in both the nucleus and the cytosol. FtbZIP85 could positively regulate PA biosynthesis by binding to the ABA-responsive element (ABRE) in the promoter of dihydroflavonol 4-reductase (FtDFR), which is a key enzyme in the phenylpropanoid biosynthetic pathway. Additionally, FtbZIP85 was also involved in the regulation of PA biosynthesis via interactions with FtSnRK2.6 but not with FtSnRK2.2/2.3. This study reveals that FtbZIP85 is a positive regulator of PA biosynthesis in TB.

Keywords: ABA; FtSnRK2.6; FtbZIP85; Tartary buckwheat; hairy roots; proanthocyanidin.

Grants and funding

Supported by the Open Project Program of Panxi Crops Research and Utilization Key Laboratory of Sichuan Province (No. SZKF2105) and the National Science Foundation of China (NSFC grants 31870240).