Abstract
Cyanidioschyzon merolae is unicellular photosynthetic eukaryote that inhabits in high temperature (42oC) and acid (pH2.5) conditions. The aim of this study is to produce transgenic stresstolerant Arabidopsis thaliana by expressing genes that are involved in adaptation of C. merolae to extreme environment. Based on EST analysis of C. merolae, we found that stromal ascorbate peroxidase (stAPX) that scavenges ROS was expressed at high level (4th of 4479 entries). To examine effect of overexpression stAPX, C. merolae stAPX (CmstAPX) or A. thaliana stAPX (AtstAPX) was stably overexpressed in A. thaliana and analyzed. Immunofluorescence microscopy showed that CmstAPX was localized in the stroma of chloroplasts in A. thaliana. CmstAPX-ox plants showed higher activities of soluble APX than those of wild-type and AtstAPX-ox plants. CmstAPX-ox plants were more tolerant to oxidative stress induced by methylviologen and high-temperature stress1. In this meeting, we will report the results of detailed analysis.
1Hirooka S et al. Expression of the Cyanidioschyzon merolae stromal ascorbate peroxidase in Arabidopsis thaliana enhances thermotolerance. (2009) Plant Cell Rep. Dec;28:1881-1893.
