FIGURE 2

P2yr1 signaling is required for spontaneous activity in supporting cells but not immature hair cells. The spatial patterns of the mean spontaneous calcium activities of the supporting cells (A1–A1′) or hair cells (B1–B1′) in DMSO and after 15 min of treatment with 1 µM MRS2500. Measurements were performed in immature neuromasts at day 3. The ΔF/F GCaMP6s signals were averaged over each 900 s interval (pre- and post-treatment) and then colorized according to the heat map and superimposed onto a baseline image. The corresponding temporal curves of the mean signal magnitude across the whole neuromast in supporting cells (A2) and in hair cells (B2) in DMSO and after 15 min of treatment with 1 µM MRS2500. The cytosolic baseline calcium in the supporting cells (C1–C1′) and hair cells (D1–D1′) in DMSO and after 15 min of treatment with 250 nM Thapsigargin. Measurements were performed in immature neuromasts at day 3. The corresponding temporal curves of the mean signal magnitude across the whole neuromast in supporting cells (C2) and in hair cells (D2) in DMSO and after 15 min of treatment with 250 nM Thapsigargin. Scale bar = 5 μm.