Fig. 4

Airineme dependent patterning and airineme targeting specificities.(A) dnCdc42 blocks airineme extension (χ²=16.4, d.f.=1, p<0.0001, N=43 cells total). (B) Interstripe melanophores persisted when airinemes were blocked with dnCdc42. Cell states are indicated by logos in lower left corners (X, aox5+ xanthophore lineage). Insets, brownish melanophores persisting from embryonic/early larval pattern and gray–black adult melanophores. (C) Airinemes contacting melanophores (arrows; M_e, early larval; M_n, new; M_p, previously differentiated; xan, xanthophore). (D) Stabilization times (median ± IQR) of aox5+ airinemes on cells of melanophore (M) or xanthophore (X) lineages for zebrafish, cx41.8 mutant zebrafish, and pearl danio. aox5+ airinemes of wild-type zebrafish were less likely to stabilize, and stabilized more briefly (*, both p<0.0001) after contacting cells of the xanthophore lineage as compared to melanophores; this target specificity was altered in cx41.8 mutant zebrafish as well as pearl danio. Y-axis is split for clarity. (E) Zebrafish aox5+ airinemes were most likely to stabilize on M_e and M_n (*, p<0.0001; median ± IQR). (F) cx41.8 mutant airinemes stabilized on aox5+ cells (arrow). (G) Vesicle transfer (arrow) to melanophore. Scale bars: 200 µm (B); 50 µm (C); 50 µm (F); 25 µm (G).