AUTHOR=Chai Tingting , Zhou Jun , Liu Jian , Xing Da 

TITLE=LSD1 and HY5 antagonistically regulate red light induced-programmed cell death in Arabidopsis

JOURNAL=Frontiers in Plant Science

VOLUME=6

YEAR=2015

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2015.00292

DOI=10.3389/fpls.2015.00292

ISSN=1664-462X

ABSTRACT=<p>Programmed cell death (PCD) in plant is triggered by abiotic and biotic stress. Light-dependent PCD is unique to plants. Light-induced PCD also requires reactive oxygen species (ROS) and salicylic acid (SA). In this study, lesion simulating disease1 (LSD1) and elongated hypocotyl 5 (HY5) perform opposite roles to regulate excess red light (RL)-triggered PCD associated with ROS and SA production. Under RL, the <italic>lsd1</italic> mutant released more ROS and SA and displayed a stronger cell death rate than the <italic>hy5</italic> mutant. It was shown that active LSD1 converted into inactive form by changing the redox status of the plastoquinone pool, and HY5 interacted with phytochrome B (phyB) to promote PCD in response to RL. LSD1 inhibited the enhanced disease susceptibility 1 (<italic>EDS1</italic>) expression by upregulating SR1, whereas HY5 enhanced the enhanced <italic>EDS1</italic> expression by binding to the G-box of the <italic>EDS1</italic> promoter. This study suggested that LSD1 and HY5 antagonistically modulated EDS1-dependent ROS and SA signaling; thus, PCD was mediated in response to RL.</p>