iDimerize technology can be used to control transcription activation of target genes very tightly. A key advantage of this iDimerize approach to transcription control is its low background, because the transcriptional activation domain (AD) is physically separated from the DNA prior to addition of the dimerizer ligand. Transcription factors are bifunctional proteins that recognize specific DNA sequences near target genes (via the DNA binding domain) and then recruit the transcriptional machinery of the cell to activate transcription (via the transcription activation domain). These two domains can work together to activate transcription even when they are expressed as individual proteins and brought together by the A/C Heterodimerizer ligand.
The iDimerize Regulated Transcription System has been designed specifically for use in regulating target genes. The genes encoding the two chimeric transcription factor domains cannot readily be reconfigured for other uses. For other heterodimerization applications, use the iDimerize Inducible Heterodimer System.
A/C Heterodimerizer Ligand (AP21967)
The A/C Heterodimerizer is a synthetic, cell-permeable ligand that can be used to induce heterodimerization of two fusion proteins. For example, when using with this kit the DmrC-tagged transcription activation domain can be induced to dimerize with the DmrA-tagged DNA binding domain. The A/C Heterodimerizer is identical to AP21967, which was previously supplied by ARIAD Pharmaceuticals Inc.
Sequentially transfect your cells of interest with:
- A plasmid which expresses the transcription activation and DNA binding components (pHet-Act1-2)
- Your gene of interest cloned downstream of the PZI-1 inducible promoter (in pZFHD1-2)
The DNA binding component remains bound to the promoter at all times, but it cannot activate transcription until it interacts with the transcription activation component via the DmrA and DmrC domains. When the A/C Heterodimerizer is added, the two components interact, and your gene of interest is transcribed from the PZI-1 promoter.