Unlike STIM1 , STIM2 has a dilysine ER retention signal ( K ( X ) KXX ) at its extreme C - terminus which retains the protein in the ER , .
STIM1 can travel to cell surface .
Unlike STIM1 , STIM2 has a dilysine ER retention signal ( K ( X ) KXX ) at its extreme C - terminus which retains the protein in the ER , whereas STIM1 can travel to cell surface .