| Here , we report a second candidate protein identified by a yeast two hybrid screen for nuclear FGF 3 action , ribosomal protein S 2 , rpS 2 . ^^^ Recombinant rpS 2 binds to in vitro translated FGF 3 and to nuclear FGF 3 extracted from transfected COS 1 cells . ^^^ Characterization of the FGF 3 binding domain of rpS 2 showed that both the Arg Gly rich N terminal region and a short carboxyl terminal sequence of rpS 2 are necessary for FGF 3 binding . ^^^ Mapping the S 2 binding domains of FGF 3 revealed that these domains are important for both NoBP and rpS 2 interaction . ^^^ Transient co expression of rpS 2 and nuclear FGF 3 resulted in a reduced nucleolar localization of the FGF . ^^^ |