Fig. 6

Hoip is a conserved regulator of myogenesis. (A,B) St16 Drosophila embryos labeled for MHC protein. Compared with hoip¹ embryos (A), hoip¹ rp298>human NHP2L1 embryos show a significant restoration of MHC protein expression and muscle morphology in the somatic mesoderm (B). (C-E) Dorsal views of 14 hpf Tg (α-actin:GFP) zebrafish embryos. Embryos injected with control MO at the one-cell stage express robust GFP in somites (C, white arrowheads). Embryos injected with nhp2l1b ATG-MO (D) or 52UTR-MO (E) do not initiate GFP expression. ATG-MO and 52UTR-MO embryos develop a distinguishable neural tube by 14 hpf (black arrowheads). (F-G2) Dorsal view of 14 hpf Tg(α-actin:GFP) zebrafish embryos labeled for GFP and MF20 (which reacts with muscle MyHC isoforms). Embryos injected with control MO show robust GFP and MF20 expression in the somatic mesoderm (F), whereas ATG-MO injected embryos display little or no GFP or MF20 staining (G). (H) Dose-dependent response to nhp2l1b MOs. Percent penetrance was calculated as the number of embryos without detectable GFP fluorescence, relative to all injected embryos. Significance between ATG-MO/52UTR-MO and Cntrl MO was calculated using a t-test. ^**P<0.01, ^***P<0.001. (I) qPCR of mesoderm transcript expression. Relative expression was calculated as mRNA levels in control versus ATG-MO-injected embryos after normalization to GAPDH. Error bars represent s.e.m.