Category:ECO:0001811 ! fluorescence anisotropy evidence

name: fluorescence anisotropy evidence
def: "A type of fluorescence evidence based on rapid and quantitative analysis of diverse molecular interactions, enzyme activities, and nucleic acid hybridization which uses a fluorophore to measure the binding constants and kinetics of reactions that cause a change in the rotational time of the molecules." [ECO:SW, PMID:20232898]
synonym: "FA" EXACT []
synonym: "Fluorescence polarization" RELATED [PMCID:3277431, PMID:20232898]
synonym: "FP" RELATED [PMCID:3277431, PMID:20232898]
is_a: ECO:0001115 ! fluorescence evidence
comment: The degree of polarization of a fluorophore is inversely related to its molecular rotation. When the fluorophore is bound to a small molecule, the rate at which it tumbles can decrease significantly from when it is bound tightly to a large protein. If the fluorophore is attached to the larger protein in a binding pair, the difference in polarization between bound and unbound states will be smaller and less accurate. The degree of binding is calculated by using the difference in anisotropy of the partially bound, free, and fully bound states measured by titrating the two binding partners. Fluorescence polarixation assays are homogeneous.