Determination of the functional domain of Vav3 involved in ERα activation. (A) Deletion constructs of Vav3. (B) Hela cells (105 cells/well in 12-well plate) were cotransfected with ERE-Luc (0.5 ug) and expression vectors (200 ng) for Vav3, Vav3*, Vav3*-ΔDH, Vav3*-ΔSH, or empty vector pHEF, as well as expression vector (50 ng) for ERα, respectively. All transfection and drug treatment are in stripped medium for 24 hours, followed by luciferase assay. Renilla luciferase as an internal control was used to normalize the data. Data are presented as the mean (± SD) of duplicate values of a representative experiment that was independently repeated for five times.