AUTHOR=Lei Rihua , Ma Zhenbing , Yu Diqiu 

TITLE=WRKY2/34–VQ20 Modules in Arabidopsis thaliana Negatively Regulate Expression of a Trio of Related MYB Transcription Factors During Pollen Development

JOURNAL=Frontiers in Plant Science

VOLUME=9

YEAR=2018

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2018.00331

DOI=10.3389/fpls.2018.00331

ISSN=1664-462X

ABSTRACT=<p>Male gametogenesis in plants is tightly controlled and involves the complex and precise regulation of transcriptional reprogramming. Interactions between WRKY proteins and VQ motif-containing proteins are required to control these complicated transcriptional networks. However, our understanding of the mechanisms by which these complexes affect downstream gene expression is quite limited. In this study, we found that <italic>WRKY2</italic> and <italic>WKRY34</italic> repress <italic>MYB97</italic>, <italic>MYB101</italic>, and <italic>MYB120</italic> expression during male gametogenesis. <italic>MYB</italic> expression was up-regulated in the <italic>wrky2-1 wrky34-1 vq20-1</italic> triple mutant during male gametogenesis. The expression levels of six potential targets of the three <italic>MYBs</italic> increased the most in the <italic>wrky2-1 wrky34-1 vq20-1</italic> triple mutant, followed by the <italic>wrky2-1 wrky34-1</italic> double mutant, compared with in wild-type. Yeast one-hybrid and dual luciferase reporter assays indicated that WRKY2 and WRKY34 recognized the <italic>MYB97</italic> promoter by binding to its W-boxes. <italic>MYB97</italic> overexpression caused defects in pollen germination and pollen tube length, which impacted male fertility. Thus, WRKY2/34–VQ20 complexes appear to negatively regulate the expression of certain <italic>MYBs</italic> during plant male gametogenesis.</p>