miR-19 disrupts axial patterning and development through post-transcriptional regulation of cyp26a1. A) Schematic of the miR-19 MO target site on the pre-miR-19d sequence that was injected into single-cell-stage embryos. B, C) Representative images of the axis defects elicited by miR-19 MO in 48 hpf embryos (C) in comparison to control (CT) MO-injected embryos (B). D) Effective knockdown of miR-19 transcript levels confirmed in miR-19 MO-injected embryos at 12 hpf via qRT-PCR. E) cyp26a1 transcript levels measured by qRT-PCR at 12 hpf in miR-19 and control morphants. (Values reflect fold change relative to control MO injected embryos, means±se, n=4.) *P < 0.05, ***P < 0.001, independent samples t test. G, F) Representative images of cyp26a1 transcript and protein expression at 24 hpf in controls (G) relative to miR-19 morphants (F), as demonstrated by in situ hybridization.