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Title: Cytoplasmic Ca2+ influx mediates iron- and reactive oxygen species-dependent ferroptotic cell death in rice immunity
Iron- and reactive oxygen species (ROS)-dependent ferroptosis occurs in plant cells. Ca2+acts as a conserved key mediator to control plant immune responses. Here, we report a novel role of cytoplasmic Ca2+influx regulating ferroptotic cell death in rice immunity using pharmacological approaches. High Ca2+influx triggered iron-dependent ROS accumulation, lipid peroxidation, and subsequent hypersensitive response (HR) cell death in rice (Oryza sativa). DuringMagnaporthe oryzaeinfection, 14 different Ca2+influx regulators altered Ca2+, ROS and Fe2+accumulation,glutathione reductase(GR) expression, glutathione (GSH) depletion and lipid peroxidation, leading to ferroptotic cell death in rice. High Ca2+levels inhibited the reduction of glutathione isulphide (GSSG) to GSHin vitro. Ca2+chelation by ethylene glycol-bis (2-aminoethylether)-N, N, N’, N’-tetra-acetic acid (EGTA) suppressed apoplastic Ca2+influx in rice leaf sheaths during infection. Blocking apoplastic Ca2+influx into the cytoplasm by Ca2+chelation effectively suppressed Ca2+-mediated iron-dependent ROS accumulation and ferroptotic cell death. By contrast, acibenzolar-S-methyl (ASM), a plant defense activator, significantly enhanced Ca2+influx, as well as ROS and iron accumulation to trigger ferroptotic cell death in rice. The cytoplasmic Ca2+influx through calcium-permeable cation channels, including the putative resistosomes, could mediate iron- and ROS-dependent ferroptotic cell death under reducedGRexpression levels in rice immune responses.  more » « less
Award ID(s):
2016143
PAR ID:
10555945
Author(s) / Creator(s):
; ; ; ; ; ; ;
Publisher / Repository:
Frontiers in Plant Science
Date Published:
Journal Name:
Frontiers in Plant Science
Volume:
15
ISSN:
1664-462X
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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