Fig. 2

Tissue Migration Rapidly Adapts to a Chemokine Flood, a Response that Is Sensitive to Cxcr7b Levels (A and B) Time lapse of lateral line migration (cldnB:lyn-GFP) in cxcr7b+/+ embryos in control (top: temperature shifted without hsp70:mCherry-cxcl12a transgene) and chemokine flood (bottom: after induction of hsp70:mCherry-cxcl12a) (A) and corresponding kymographs (B). Scale bars, 100 μm (A) and 50 μm (B). Timescale 1 h per bar. See Video S1A. (C) Lateral line migration velocity over time (h post-heat shock); control (blue) and chemokine flood (red). (D) Migration velocity in chemokine flood (n = 12, red) relative to the mean of control (n = 12, blue). Shadings, standard deviations. (E) Migration in cxcr7b+/+ or cxcr7b+/− embryos 24 h after chemokine flood. hsp70:mCherry-cxcl12a transgenics distinguished by the green heart marker (clmc2:GFP, asterisk). (F) Boxplot, median, and quantiles of normalized distance migrated. Statistics: p values indicated on the plot. (G) Time lapse of the Cxcr7b-GFP-expressing lateral line in control (left) or chemokine flood (right). Scale bar, 50 μm. See Video S2. (H) Cxcr7b-GFP fluorescence intensity over time, control (blue) and chemokine flood (red). (I) Cxcr7b-GFP and Cxcr4b-GFP intensities in chemokine flood relative to the mean of the control over time. Cxcr7b-GFP n = 30 and 29 and Cxcr4b-GFP n = 9 and 9. (J) Images of Cxcr7b-GFP in control (left) or chemokine flood (right). Single optical slices allow intensity comparison (calibration bar, signal intensity). Scale bar, 10 μm. (K) Lateral views of (J). Insets: Cxcr7b-GFP with PM label (krt15:lyn-RFP). Scale bar, 10 μm. (L) Quantification of the distance of local fluorescence point densities from tissue apex in control and chemokine flood.