Fig. 7. IP3R and 3F3A colocalise to mitochondria-associated ER but segregate upon ATP treatment. (A) MDCK cells either untreated or treated with 10 µM ATP for 2 or 5 minutes were fixed and immunofluorescently labelled for IP3R, 3F3A and mitochondrial ATP-synthase (subunit ). (B) Details of zoomed regions from merges of 3F3A (red) and IP3R (green). (C) The extent of colocalisation of 3F3A and IP3R-labelled ER domains with mitochondria and between the 3F3A and IP3R-labelled ER domains at various times of ATP treatment was quantified using the Pearson coefficient. ^*P<0.01; ^**P<0.005 relative to 0 min. Bars, 20 µm (A); 2 µm (B).