Transcriptome analysis of dark-grown cop1 and cop1BBX22-GFPox plants

The proper accumulation of BBX22 mediated by COP1 is crucial for plants to maintain better growth fitness when growing in the dark environment as well as responding to seasonal changes in day-length. The constitutive-photomorphogenic development of the cop1 mutant is enhanced in cop1BBX22-GFPox plants, which show a short hypocotyl, high anthocyanin accumulation and expression of light-responsive genes. Target genes responsible for the exaggerated light phenotype in cop1BBX22-GFPox plants were revealed by comparing transcriptomes among dark-grown wild-type, cop1 and cop1BBX22-GFPox plants. Expression of genes regulated by light and multiple hormones are altered in plants over-accumulating BBX22, implying a coordination role of BBX22 in light- and hormone-mediated seedling development. Three biological replicates for 4-day-old etiolated seedlings of wild type (Col-0) and two mutants (cop1-4 and cop1-4BBX22-GFPox).