ANO8 increases interaction of STIM1-Orai1 and STIM1-STIM1 at the ER/PM junctions to control Ca2+ influx.Figure 1(A) HEK cells transfected with STIM1-CFP, Orai1-mCherry, and with (red) or without (black) untagged ANO8 were used to measure CRAC current with pipette solution (cytoplasmic buffer) containing 3 mM EGTA. The columns show the averaged effect of ANO8 on current density and on the slop of slow Ca2+-dependent inactivation (SCDI). The results are mean±s.e.m and difference were analyzed by unpaired t test. Data information: The first number in parenthesis indicates the number of similar experiments performed and the second number is the number of cells analyzed. All results are given as mean±s.e.m of the indicated number of experiments or cells analyzed. (B) Fura2-loaded HEK cells transfected with YFP (control, black) or ANO8-YFP (red) were used to measure store-mediated Ca2+ influx. Stores were depleted by treatment with the SERCA inhibitor CPA and Ca2+ influx was measured by Ca2+ add-back. The results are mean±s.e.m and difference were analyzed by unpaired t test. Data information: The first number in parenthesis indicates the number of similar experiments performed and the second number is the number of cells analyzed. All results are given as mean±s.e.m of the indicated number of experiments or cells analyzed. (C) FRET efficiency was measured with HEK cells transfected with STIM1-CFP, ANO8-YFP, and with (red) and without (black) Orai1-HA before and after store depletion. Here and all other FRET measurements, representative images of the FRET signal under each condition are shown next to the traces. Data information: The first number in parenthesis indicates the number of similar experiments performed and the second number is the number of cells analyzed. All results are given as mean±s.e.m of the indicated number of experiments or cells analyzed. (D) Summary of FRET efficiency measurements at the indicated conditions. The results are mean±s.e.m and difference were analyzed by unpaired t test. Data information: The first number in parenthesis indicates the number of similar experiments performed and the second number is the number of cells analyzed. All results are given as mean±s.e.m of the indicated number of experiments or cells analyzed. (E) FRET efficiency was measured with HEK cells transfected with STIM1-CFP, STIM1-YFP (blue), and co-transfected with untagged ANO8 (green) or treated with siANO8 (red) before and after store depletion. Data information: The first number in parenthesis indicates the number of similar experiments performed and the second number is the number of cells analyzed. All results are given as mean±s.e.m of the indicated number of experiments or cells analyzed. (F) Resting (R) or store-depleted cells (S) HEK cells transfected with STIM1-YFP and myc-STIM1 and with or without ANO8 or treated with siANO8, were used to immunoprecipitate (IP) STIM1-YFP and blot (B) for mys-STIM1. The inputs (In) are with anti-myc, anti-YFP or anti-ANO8. Data information: The first number in parenthesis indicates the number of similar experiments performed and the second number is the number of cells analyzed. All results are given as mean±s.e.m of the indicated number of experiments or cells analyzed. (G) Confocal and bright field images of basal (upper) and store depleted cells (lower) of HEK cells transfected with ANO8-YFP alone. Data information: The first number in parenthesis indicates the number of similar experiments performed and the second number is the number of cells analyzed. All results are given as mean±s.e.m of the indicated number of experiments or cells analyzed. The experiments represent at least 4 separate experiments with similar results. (H) TIRF images (upper) and TIRF-Z scan (lower) of the same resting and store depleted cells HEK cells transfected with ANO8-YFP alone. Data information: The first number in parenthesis indicates the number of similar experiments performed and the second number is the number of cells analyzed. All results are given as mean±s.e.m of the indicated number of experiments or cells analyzed. The experiments represent at least 4 separate experiments with similar results. (I): Confocal images of resting cells transfected with ANO8-YFP, STIM1-CFP and Orai1-mCherry. (J) Confocal images of store depleted cells transfected with ANO8-YFP, STIM1-CFP and Orai1-mCherry. Data information: The first number in parenthesis indicates the number of similar experiments performed and the second number is the number of cells analyzed. All results are given as mean±s.e.m of the indicated number of experiments or cells analyzed. The experiments represent at least 4 separate experiments with similar results. (K) TIRF-Z scan of resting (upper) and store depleted (lower) cells transfected with ANO8-YFP and STIM1-mCherry demonstrating the relationship between STIM1 and ANO8 puncta at the TIRF field. Cell surface is on top. Data information: The first number in parenthesis indicates the number of similar experiments performed and the second number is the number of cells analyzed. All results are given as mean±s.e.m of the indicated number of experiments or cells analyzed. The experiments represent at least 4 separate experiments with similar results.