Fig. 5

Fig. 5 cxcr7b expression begins at a constant distance from the leading edge. (A,B) cxcr7b in situ hybridization labels the trailing portion of the primordium. (A) Example of a long primordium that is about to deposit a proneuromast. Such long primordia possess a relatively wide cxcr7b expression domain. (B) A primordium that has just deposited a proneuromast. Most of the cxcr7b expressing cells were deposited yielding a short primordium with a relatively narrow cxcr7b expression domain. Total length (green), length of the cxcr7b expression domain (blue), and the length of the cxcr7b-free domain (red) were measured in primordia during various phases of the deposition cycle (n = 8). (C) The length of the cxcr7b expression domain fluctuates with primordium length. Longer primordia about to deposit have longer cxcr7b expression domains (slope = 0.9; R2 = 0.80). (D) The length of the cxcr7b free zone remains relatively constant as primordium size fluctuates (slope = 0.1). Scale bar equals 50 μm.