A method (gel mobility shift assay, bandshift assay) often used in studying DNA–protein interactions, although in principle applicable to any binding interaction. DNA that has bound a protein such as a transcription factor has a larger size and thus runs more slowly on a gel (i.e. is retarded). The method can be used to estimate the amount of a DNA-binding protein present by quantifying the proportion of radiolabelled DNA that is retarded.
Subjects: Medicine and Health.