AUTHOR=Yan Qiang , Si Jierui , Cui Xiaoxia , Peng Hao , Jing Maofeng , Chen Xin , Xing Han , Dou Daolong 

TITLE=GmDAD1, a Conserved Defender Against Cell Death 1 (DAD1) From Soybean, Positively Regulates Plant Resistance Against Phytophthora Pathogens

JOURNAL=Frontiers in Plant Science

VOLUME=10

YEAR=2019

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2019.00107

DOI=10.3389/fpls.2019.00107

ISSN=1664-462X

ABSTRACT=<p>Initially identified as a mammalian apoptosis suppressor, defender against apoptotic death 1 (DAD1) protein has conserved plant orthologs acting as negative regulators of cell death. The potential roles and action mechanisms of plant DADs in resistance against <italic>Phytophthora</italic> pathogens are still unknown. Here, we cloned <italic>GmDAD1</italic> from soybean and performed functional dissection. <italic>GmDAD1</italic> expression can be induced by <italic>Phytophthora sojae</italic> infection in both compatible and incompatible soybean varieties. By manipulating <italic>GmDAD1</italic> expression in soybean hairy roots, we showed that <italic>GmDAD1</italic> transcript accumulations are positively correlated with plant resistance levels against <italic>P. sojae</italic>. Heterologous expression of <italic>GmDAD1</italic> in <italic>Nicotiana benthamiana</italic> enhanced its resistance to <italic>Phytophthora parasitica</italic>. <italic>NbDAD1</italic> from <italic>N. benthamiana</italic> was shown to have similar role in conferring <italic>Phytophthora</italic> resistance. As an endoplasmic reticulum (ER)-localized protein, GmDAD1 was demonstrated to be involved in ER stress signaling and to affect the expression of multiple defense-related genes. Taken together, our findings reveal that <italic>GmDAD1</italic> plays a critical role in defense against <italic>Phytophthora</italic> pathogens and might participate in the ER stress signaling pathway. The defense-associated characteristic of <italic>GmDAD1</italic> makes it a valuable working target for breeding <italic>Phytophthora</italic> resistant soybean varieties.</p>