The JAK2 JH2 Pseudokinase Domain Inhibitor Screening Assay Kit is designed for screening and profiling small molecules that displace the fluorescently labeled probe (JH2 probe 1) from the JH2 domain of JAK2. The assay is a fluorescence polarization (FP) assay based on the competition of the test compound with the JH2 probe for binding to purified JAK2 JH2.

JH2 probe 1 is a small molecule probe that binds to the ATP-binding site of JAK2 pseudokinase domain JH2. The probe has been labeled with a fluorescent tracer, so that binding of the probe to much larger JH2 results in noticeable increases in fluorescence polarization compared to the unbound fluorescent probe (depolarized). Competition between a test drug and the probe results in changes in polarization.

Using this kit, only one simple step on a microplate is required for screening. The JH2 probe 1 is incubated with a sample containing JAK2 JH2 to produce a change in fluorescent polarization that can then be measured using a fluorescence microplate reader capable of measuring fluorescence polarization.