Transcription factor-dna binding assay

Abstract

Pharmacological agents useful in the diagnosis or treatment of disease associated with the expression of a gene are identified in high throughput drug screening assays. The methods involve combining a labeled transcription factor, a nucleic acid coupled to a ligand, a candidate pharmacological agent and a receptor immobilized on a solid substrate, such as a microtiter plate, filter, or bead. The nucleic acid has at least that portion of a nucleotide sequence naturally involved in the regulation of the transcription of the gene which is necessary for sequence-specific interaction with the transcription factor. The resultant combination is incubated under conditions whereby the receptor is bound to the ligand and, but for the presence of said candidate pharmacological agent, the transcription factor is sequence-specifically bound to the nucleic acid. Unbound transcription factor is then removed or washed from the solid substrate and labelled, sequence-specifically bound transcription factor is detected. Incubates which include candidate agents which alter transcription factor binding deviate from control incubates in terms of label signal--typically, binding is disrupted and the signal is diminished. In a preferred embodiment, the entire process is performed by a computer-controllable electromechanical robot with an axial rotatable arm.