Transcriptome in Arabidopsis yellow variegated 2 (var2)

ABSTRACT: The yellow variegated2 (var2) mutant in Arabidopsis thaliana has been studied as a typical leaf-variegated mutant whose defect results from the lack of FtsH2 metalloprotease in chloroplasts. The var2 green sectors suffer from photooxidative stress and accumulate high levels of reactive oxygen species (ROS) because of compromised Photosystem II repair. This study investigated and compared microarray-based expression profiles of green and white sectors of var2 leaves. Results suggest that ROS that accumulate in chloroplasts of var2 green sectors do not cause much significant change of the transcriptional profile related to ROS signaling and scavenging. In contrast, transcriptome in white sectors apparently differs from those in green sectors and wild type. Numerous genes related to photosynthesis and chloroplast functions were repressed in white sectors. Furthermore, many genes related to oxidative stress were up-regulated. Among them, we specifically examined ROS scavenging genes, such as Cu/Zn superoxide dismutase 2 (CSD2), that were apparently up-regulated in white but not in green sectors. Up-regulation of CSD2 appears to be partly attributable to the lack of a microRNA (miR398) in white sectors. Together, we concluded that white sectors exhibit response to oxidative and other stresses, including CSD2 up-regulation, which might be commonly found in tissues with abnormal chloroplast differentiation.

ORGANISM(S): Arabidopsis thaliana

PROVIDER: GSE18646 | GEO | 2010/03/31

SECONDARY ACCESSION(S): PRJNA121581

REPOSITORIES: GEO