PathHunter Nuclear Translocation Assays measure the effect of compounds on nuclear hormone receptor translocation in vivo using a fast, homogeneous microplate-based test. After signaling pathway activation, two β-galactosidase fragments — differentially expressed in the nucleus and cytoplasm — can complement and chemiluminescent signal is detected with a standard luminometer after only 60 minutes of incubation. These 384-well assays routinely have large S:B ratios (>10) with high z’ factors. PathHunter Biosensor Cell Lines are available for the Androgen Receptor, Liver X Receptor alpha, Vitamin D Receptor, and Glucocorticoid Receptor.