Growth and Environmental Change-Independent Genes Associated with Clock Gene TOC1 in Green Perilla

Secondary metabolism is regulated by circadian rhythm based on the clock genes expression. Transcriptome analysis is an important tool to understand these mechanisms. However, sufficient genetic information for this analysis is lacking for many crops. In order to analyze the influence of independent clock genes from growth and environmental stimulation, we investigated the gene expression profiles in the roots and leaves of green perilla (Perilla frutescens), which is an important crop used as a herbal medicine. Green perilla was grown under light emitting diode and fluorescent light, after 7, 14, and 35 d. We also compared the coding DNA sequences with those in the other plants. From the transcriptomic data, green perilla was observed to have 74 contigs that did not depend on growth and cultivation condition. Some of these 74 genes might be related to the clock genes through their interactions with other genes. Some 74 genes had TATA box-like motif and a GA motif of the genes that are regulatory targets of timing of CAB expression 1 (TOC1). Thus, 74 genes that did not depend on cultivation condition and growth were considered to be under the control of TOC 1, suggesting the importance of TOC1 in circadian rhythms.