Poster: Seed Biology

Abs # 560: The involvement of ROS in the regulation of programmed cell death of the megagametophyte of white spruce (Picea glauca) seeds following germination

Presenter:	He, Xu , xhe@sfu.ca
Authors	He, Xu  (A)   Kermode, Allison R (A)
Affiliations:	(A): Simon Fraser University

The megagametophyte of white spruce (Picea glauca) seeds undergoes programmed cell death following seed germination. During this process, the peak of ROS (reactive oxygen species) production occurs when most of the cells are dying. Treatment of germinating seeds with low concentrations of H₂O₂ resulted in an incremental enhancement of ROS- scavenging enzyme activities, and the cell death process was delayed. DPI, an inhibitor of NADPH oxidase, and Tiron (a H₂O₂ scavenger) decreased ROS generation and slowed cell death. Furthermore, the ethylene biosynthesis inhibitor, AVG, inhibited ROS production and delayed cell death. When germinating seeds were treated with AVG and ABA, the death of megagametophyte cells was further postponed. These results suggest that ROS is involved in the regulation of death of megagametophyte cells and hormones such as ethylene and ABA regulate cell death in part by monitoring ROS production.