Abstract
CRES-T system (Chimeric REpressor gene-Silencing Technology) is a reliable gene-silencing system using the chimeric transcriptional repressor. Transcription factors can be changed into transcriptional repressors by connecting the transcription repression domain (SRDX). The chimeric repressor dominantly suppresses the target genes. In some cases, it caused a growth defect and a decrease in fertilization. In this study, we developed a new system toward the improvement of genetically modified floricultural plants. The GAL4SRDX, which is an yeast transcription factor with the repression domain, was used to repress the over-expressed chimeric repressor under CaMV35S promoter::GAL4 UAS. The chimeric repressor of AGAMOUS (AGSRDX) which caused double-petaled flower, and the chimeric repressor of DUPLICATE (DPSRDX) which is a homolog of AG in Pharbitis was introduced to Arabidopsis and Pharbitis, respectively. The growth of regenerating shoots of Pharbitis transformed with CaMV35S::DPSRDX was defective. However, using our new system, GAL4SRDX could repress the DPSRDX during redifferentiation, and we succeeded to bloom double-petaled Pharbitis flower.
