Fig. 6

An example of the Ca2+ signals generated in the trunk of a wild-type embryo at ~18.5 hpf as visualized by confocal microscopy using calcium green-1 dextran. (Ai-Av) Representative (n=3) single confocal sections to show the Ca²⁺ signals generated in somites 7, 8, 9 and 10 at ~18.5 hpf (i.e., the 19-somite stage). The time interval between each image was 1.16 sec. The color scale represents the level of [Ca²⁺]i, where red indicates a high level and blue indicates a low level. Ant. and Pos. are anterior and posterior, respectively. Scale bar is 50 μm. (Bi- Biv) Temporal profiles of average calcium green-1 dextran fluorescence intensity (in Arb. units) recorded in four ROIs (each covering ~4-5 SMCs, i.e., ~800 μm²) placed in the middle of somites 7, 8, 9 and 10 of this wild-type embryo at ~18.5 hpf (see schematic, panel Bi*). The three red dashed lines help to illustrate the synchronized nature of these signals. (Bv) Temporal profile of average rhodamine B dextran fluorescence intensity (in Arb. units) recorded in an ROI placed in the middle of somite 8 (see schematic, panel Bv*). (C) Temporal profiles of average calcium green-1 dextran fluorescence intensity (in Arb. units) in the dorsal (green), medial (red) and ventral (blue) regions of somite 9, which indicate that the majority of the Ca²⁺ signals in the dorsal, medial and ventral regions of the somite also occur in synchrony. (C*) Schematic to show the dorsal (D), medial (M) and ventral (V) ROIs.