Fig. 3

Knockdown of Tuba1a, but not Tuba1b, suppresses CNS formation in developing embryos. Control, tuba1a or tuba1b-targeting morpholinos (MO) were injected into single cell zebrafish embryos. Top graphs show that tuba1a MO-dependent phenotypes at 30 h post fertilization (hpf) are concentration-dependent (tuba1a MO concentrations are 0, 0.065, 0.125 and 0.25 mM; control MO was used to keep total MO concentrations at 0.25 mM). Bottom images show representative pictures of MOinjected (0.125 mM) embryo phenotypes at 30 and 52 hpf. To inhibit apoptosis and examine MO specificity, some experiments included in vitro transcribed bcl2 mRNA (25 pg) or tuba1a mRNA (12.5 pg) that was engineered to escape MO-mediated knockdown. Note that tuba1a, but not tuba1b MO severely disrupted development, especially of anterior structures; however, inclusion of bcl2 or tuba1a mRNA diminished the severity of Tuba1a knockdown. Three different tuba1a mRNA rescue phenotypes are shown at 52 hpf. Similar results were obtained with a second MO targeting different tuba1a and tuba1b sequences.