ER Filter Plate assay

ERs (ERalpha and ERbeta) mediate cellular signaling of estrogens, belonging to the nuclear receptor family of transcription factors. The mechanism of regulatory actions of ERs is that ligand-bound ERs bind directly to estrogen response elements (ERE), in the promoters of target genes or via protein-protein interactions with other transcription factors. The dysfunction of ERs has been demonstrated to be closely related with breast cancer, prostate cancer and lung cancer. Signosis has developed ER filter assay. Unlike conventional gel shift assays, ER filter assay is a high throughput assay and it can analyze multiple samples simultaneously. Meanwhile, the assay can be set up for a few samples with less tedious than non-radioactive gel shift assay or much safe than 32P-based gel shift assay.

A. Benefits:

Signosis proprietary ER filter plate assay offers following benefits:

• Simple and quick -It is simpler and quicker than gel shift assay.

• High throughput screen- Multiple samples can be analyzed in one single assay.

• Cost-effective detection- The cost is lower than ELISA-based TF assays.

• Quantitative comparison The difference of two or more samples in TF activity can be quantitatively analyzed.

B. Principle of the technology

Signosis’ ER filter plate assay is a plate-based analysis for monitoring the DNA binding activity of ER. In the assay, two plates – filter plate and hybridization plate – are needed. In the assay, pre-labeled ER binding element (ERE) is mixed with nuclear extract to allow formation of ER/probe complex. The filter is used to retain bound ERE probe and remove free probe. The bound ERE probe is then eluted from the filter and collected for plate hybridization. The captured probe is further detected with streptavidin-HRP. Luminescence is reported as relative light units (RLUs) on a microplate luminometer.