Fig. 2.

Mutant IP₃Rs attenuate association of STIM and Orai after store depletion. (A) Western blots from brains of larval Drosophila expressing Orai–CFP with WT or mutant IP₃Rs, and treated with thapsigargin (TG, 10 µM in Ca²⁺-free HBM for 10 min) as indicated. The input lysates (equivalent to 20% of the immunoprecipitated sample) and anti-GFP immunoprecipitates (IP) are shown. α-tubulin provides a loading control. The positions of molecular mass markers (kDa) are shown between blots. (B) Summary results for the ratio of the intensities of the STIM to Orai–CFP bands (mean±s.e.m., n=3). *P<0.05, paired Student's t-test relative to the respective control. (C) WT brains expressing STIM–YFP show results of immunoprecipitation (with anti-GFP antibody) after treatment with thapsigargin as indicated. The lysate lanes contain the equivalent of 20% of the immunoprecipitated sample lanes. (D) Summary results show the ratio of the intensities of the Orai to STIM–YFP bands (mean and individual values are shown; n=2).