SP1 Transcription Factor Activity Assay

The SP1 Transcription Factor Activity Assay from Assay Genie is a DNA-binding ELISA-format kit used to measure the functional DNA-binding activity of the SP1 transcription factor in nuclear and cell lysates. SP1 (Specificity Protein 1) is a zinc-finger transcription factor that recognizes GC-box consensus sequences (5'-GGGCGG-3') in gene promoters and regulates many housekeeping and tissue-specific genes. Rather than quantifying total SP1 protein, this assay captures the active fraction of SP1 capable of binding its cognate DNA motif, making it useful for studying transcriptional regulation, signal-transduction effects on promoter activity, and comparative binding studies across human, mouse, and rat samples.

The microplate is pre-coated with an oligonucleotide containing the SP1 consensus binding site. Nuclear extract is added, and SP1 present in the sample binds to the immobilized probe. Bound SP1 is then detected with a primary antibody specific for SP1 followed by an HRP-conjugated secondary antibody and a chromogenic substrate, producing a measurable absorbance signal proportional to transcription factor DNA-binding activity. The kit is compatible with standard ELISA plate readers and is supplied as a complete set of reagents sufficient for 96 individual determinations. Recommended storage is at -20 °C for long-term stability of components, with multiple freeze-thaw cycles avoided by aliquoting working stocks; bring all reagents to room temperature before use. For research use only.