Micro scale thermophoresis (MST)
GFP-AR constructs were purchased from Gene-Script (China). Each construct was transfected into PC3 cells and the total protein was obtained in MST buffer followed by addition of SBF-1 in serial dilution of 16 folds. The assay was performed as reported (Wienken, Baaske, Rothbauer, Braun & Duhr, 2010) and the binding affinity was checked using Monolith NT.115.