AUTHOR=Wang Feng-Pan , Zhao Pan-Pan , Zhang Lei , Zhai Heng , Abid Muhammad , Du Yuan-Peng 

TITLE=The VvWRKY37 Regulates Bud Break in Grape Vine Through ABA-Mediated Signaling Pathways

JOURNAL=Frontiers in Plant Science

VOLUME=13

YEAR=2022

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2022.929892

DOI=10.3389/fpls.2022.929892

ISSN=1664-462X

ABSTRACT=<p>Dormancy is a common survival strategy in plants to temporarily suspend visible growth under unsuitable conditions. The elaborate mechanism underlying bud break in perennial woody plants is gradually illustrated. Here, we identified a grape vine WRKY transcription factor, <italic>VvWRKY37</italic>, which was highly expressed in dormant buds. It was particularly induced by the application of exogenous abscisic acid, and depressed on exposure to gibberellin and low temperature (4°C) stress at the transcript level. The yeast one-hybrid assay confirmed that VvWRKY37 had a transcriptional activity. Ectopic over-expression of <italic>VvWRKY37</italic> significantly delayed bud break of transgenic poplar plants. As an ABA-inducible gene, <italic>VvWRKY37</italic> also depressed the expression of ABA catabolic gene <italic>CYP707A</italic>s and enhanced the accumulation of endogenous ABA in transgenic poplar plants. The molecular pieces of evidence showed that VvWRKY37 preferentially recognized and bound W-box 5′-G/CATTGACT/C/G-3′ <italic>cis</italic>-element <italic>in vitro</italic>. Additionally, VvABI5 and VvABF2 acted as the upstream transcriptional activators of <italic>VvWRKY37 via</italic> protein-DNA interactions. Taken together, our findings provided valuable insights into a new regulatory mechanism of WRKY TF by which it modulates bud break through ABA-mediated signaling pathways.</p>