| BSAP ( Pax 5 ) importin alpha 1 ( Rch 1 ) interaction identifies a nuclear localization sequence . ^^^ Using the yeast two hybrid system , we identified importin alpha 1 ( Rch 1 ) as a BSAP interacting protein . ^^^ BSAP ( Pax 5 ) importin alpha 1 ( Rch 1 ) interaction identifies a nuclear localization sequence . ^^^ |