Figure 1

Expression pattern and function of Ncam1 during development of the zebrafish lateral line system. (A–D) Lateral views of Tg(ClaudinB::lynGFP) (green) embryos (48 hpf) immunostained for Ncam1a or Ncam1b (magenta). (A,C) Control-Morpholino (Co-Mo) injected sibling; all structures (excluding interneuromast cells) of the lateral line system express Ncam1a and Ncam1b. (A′-A‴,C′-C‴) Ncam1a is expressed throughout the whole primordium (arrowhead), whereas Ncam1b is found only in the Trailing-Zone. (B)ncam1a-morphants show only weak migration defects and (B′-B‴) primordium length is not affected. (D) Morpholino-knockdown of ncam1b induces migration defects as well as a reduction in the number of deposited (pro)neuromasts. (D′-D‴)ncam1b-knockdown also results in a reduced primordium size. (E,F,G) Quantification of migration distance, primordium length and number of neuromasts in control and morpholino-injected embryos. Rescue mRNA was co-injected with the morpholino as indicated. Error bars represent standard deviation. Scale bars (A,D) 200 μm, (D‴) 20 μm. Abbreviations: Co-Mo, Control-Morpholino; L1-6, lateral (pro)neuromast; pLLG, lateral line ganglion; pLLN, lateral line nerve; ov, otic vesicle; PrimI, primary posterior primordium.