Abstract
Arabidopsis thaliana RD20 gene is highly responsive to dehydration, high salinity, ABA treatment and pathogen infection as target of many stress-responsive transcription factors such as RD26 (NAC) or AREB1 (bZIP). RD20 encodes a calcium binding EF-hand protein that is a member of caleosin family, which was first recognized as oil body proteins. The RD20 protein was detected in microsome fraction. Transient expression of RD20:YFP fusion protein in Arabidopsis protoplast cells revealed that RD20 likely to be localized in endoplasmic reticulum.
To analyze biological function of RD20, we constructed RD20 over-expressing plants and obtained rd20 knock out mutants. These mutants showed no morphological phenotype under normal condition. Phenotypes of mutants under stress condition will be shown and together with the results of yeast two-hybrid analysis, the role of RD20 in stress-response of plant will be discussed.
