Fig. 4

(A) Convergent silencing of the miR-27a/b genes with ubiquitin promoters driving both sense and antisense transcription. A synthetic DNA sequence encompassing precursor sequences for both miR-27a and miR-27b were directly cloned between the two promoters. (B) Compared to control embryos injected with dye only (DIC), lateral and ventral views show that CT-miR-27a/b injected embryos phenocopy miR-27a/b morphants (see Supplemental Figure 4) with defects in pharyngeal arch morphogenesis, craniofacial defects, and inhibition of pectoral fin outgrowth as shown by decreased staining of ECM (cartilage) with alcian blue. (C) Compared to DICs, craniofacial defects observed with alcian blue staining were observed in 8–9.5% of CT-miR-27a/b embryos using two different plasmid clones of the construct in (A). n = 191 for DIC, n = 458 for CT-miR-27a/b clone 1, and n = 272 for CT-miR-27a/b clone 2. All images are at 4dpf.