PT  - JOURNAL ARTICLE
AU  - Zhu, Qing-gang
AU  - Gong, Zi-yuan
AU  - Huang, Jingwen
AU  - Grierson, Donald
AU  - Chen, Kun-song
AU  - Yin, Xue-ren
TI  - High-CO<sub>2</sub>/Hypoxia-Responsive Transcription Factors DkERF24 and DkWRKY1 Interact and Activate <em>DkPDC2</em> Promoter
AID  - 10.1104/pp.18.01552
DP  - 2019 May 01
TA  - Plant Physiology
PG  - 621--633
VI  - 180
IP  - 1
4099  - http://www.plantphysiol.org/content/180/1/621.short
4100  - http://www.plantphysiol.org/content/180/1/621.full
SO  - Plant Physiol.2019 May 01; 180
AB  - Identification and functional characterization of hypoxia-responsive transcription factors is important for understanding plant responses to natural anaerobic environments and during storage and transport of fresh horticultural products. In this study, yeast one-hybrid library screening using the persimmon (Diospyros kaki) pyruvate decarboxylase (DkPDC2) promoter identified three ethylene response factor (ERF) genes (DkERF23/DkERF24/DkERF25) and four WRKY transcription factor genes (DkWRKY/DdkWRKY5/DkWRKY6/DkWRKY7) that were differentially expressed in response to high CO2 (95%, with 4% N2 and 1% oxygen) and high N2 (99% N2 and 1% oxygen). Yeast one-hybrid assays and electrophoretic mobility shift assays indicated that DkERF23, DkERF24, DkERF25, DkWRKY6, and DkWRKY7 could directly bind to the DkPDC2 promoter. Dual-luciferase assays confirmed that these transcription factors were capable of transactivating the DkPDC2 promoter. DkERF24 and DkWRKY1 in combination synergistically transactivated the DkPDC2 promoter, and yeast two-hybrid and bimolecular fluorescence complementation assays confirmed protein–protein interaction between DkERF24 and DkWRKY1. Transient overexpression of DkERF24 and DkWRKY1 separately and in combination in persimmon fruit discs was effective in maintaining insolubilization of tannins, concomitantly with the accumulation of DkPDC2 transcripts. Studies with Arabidopsis (Arabidopsis thaliana) homologs AtERF1 and AtWRKY53 indicated that similar protein–protein interactions and synergistic regulatory effects also occur with the DkPDC2 promoter. We propose that an ERF and WRKY transcription factor complex contributes to responses to hypoxia in both persimmon fruit and Arabidopsis, and the possibility that this is a general plant response requires further investigation.