Fig. 1

Skeletal muscle abnormalities in ddx27 mutant zebrafish.

(A) Microscopic visualization of control and mutant larval zebrafish (osoi) at 5 days post fertilization (dpf). Mutant fish display leaner muscles (left panel) and exhibit highly reduced birefringence in comparison to control (right panel). Mutant fish also exhibit pericardial edema (arrow) (B) Genetic mapping of osoi mutant by initial bulk segregant analysis identified linkage on chromosome 6. Fine mapping of chromosome 6 resolved flanking markers z41548 and z14467, with a candidate genome region containing six candidate genes that were sequenced by Sanger sequencing (C) Overexpression of human DDX27 mRNA results in a significant decrease in mutant zebrafish phenotype (D) Whole-mount Immunofluorescence was performed on control and ddx27 mutant larvae (Z-stack confocal image, 4dpf) (scale bar: 50μm) (E) Immunofluorescence on newly isolated (Day 0) and cultured (Day1 and 3) EDL myofibers from wild-type mice (scale bar: 10μm). (F) Western blot showing relative expression of Ddx27 and myogenic markers (MyoD, MyoG and MF20) in proliferating C2C12 myoblasts in growth media (50% confluence) or in differentiation media for 3 days (D0-3). GAPDH was used as the control. (G) Schematic diagram of nucleolus depicting nucleolar domains. Eukaryotic nucleolus has tripartite architecture: Fibrillar center (FC); Dense fibrillar component (DFC) and granular compartment (GC). Immunofluorescence of human myoblasts with DDX27 and nucleolar markers labeling each compartment of nucleolus (scale bar: 2μm).