AUTHOR=Fan Sujie , Dong Lidong , Han Dan , Zhang Feng , Wu Junjiang , Jiang Liangyu , Cheng Qun , Li Rongpeng , Lu Wencheng , Meng Fanshan , Zhang Shuzhen , Xu Pengfei 

TITLE=GmWRKY31 and GmHDL56 Enhances Resistance to Phytophthora sojae by Regulating Defense-Related Gene Expression in Soybean

JOURNAL=Frontiers in Plant Science

VOLUME=8

YEAR=2017

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2017.00781

DOI=10.3389/fpls.2017.00781

ISSN=1664-462X

ABSTRACT=<p>Phytophthora root and stem rot of soybean [<italic>Glycine max</italic> (L.) Merr.] caused by the oomycete <italic>Phytophthora sojae</italic>, is a destructive disease worldwide. The molecular mechanism of the soybean response to <italic>P. sojae</italic> is largely unclear. We report a novel WRKY transcription factor (TF) in soybean, GmWRKY31, in the host response to <italic>P. sojae</italic>. Overexpression and RNA interference analysis demonstrated that GmWRKY31 enhanced resistance to <italic>P. sojae</italic> in transgenic soybean plants. GmWRKY31 was targeted to the nucleus, where it bound to the W-box and acted as an activator of gene transcription. Moreover, we determined that GmWRKY31 physically interacted with GmHDL56, which improved resistance to <italic>P. sojae</italic> in transgenic soybean roots. GmWRKY31 and GmHDL56 shared a common target <italic>GmNPR1</italic> which was induced by <italic>P. sojae</italic>. Overexpression and RNA interference analysis demonstrated that <italic>GmNPR1</italic> enhanced resistance to <italic>P. sojae</italic> in transgenic soybean plants. Several pathogenesis-related (<italic>PR</italic>) genes were constitutively activated, including <italic>GmPR1a</italic>, <italic>GmPR2</italic>, <italic>GmPR3</italic>, <italic>GmPR4</italic>, <italic>GmPR5a</italic>, and <italic>GmPR10</italic>, in soybean plants overexpressing <italic>GmNPR1</italic> transcripts. By contrast, the induction of <italic>PR</italic> genes was compromised in transgenic <italic>GmNPR1</italic>-RNAi lines. Taken together, these findings suggested that the interaction between GmWRKY31 and GmHDL56 enhances resistance to <italic>P. sojae</italic> by regulating defense-related gene expression in soybean.</p>