Fig. 5

Fig. 5 Rbfox1l/rbfox2 knockdown alters myofibril organization. (A–D) Anti-MHC immunohistochemistry at 24 and 48 hpf reveals that slow muscle fibers in rbfox1l/rbfox2 morphants are disorganized compared to normally striated fibers in wildtype muscle (A, C vs. B, D). (E–J) Immunohistochemistry with Alexa-Fluor 488-conjugated phalloidin, which labels F-actin, reveals that slow and fast muscle thin filaments are elongated and highly organized in wildtype embryos at 24 and 48 hpf, respectively (E, G), whereas thin filament structure is severely disrupted in Rbfox1l/rbfox2 morphants (F, H). Defects in myofiber organization (I–J) are less severe at lower rbfox1l/rbfox2 MO doses (1.5 ng each) when compared to higher doses (7 ng each). Doses in B, D, F, and H = 4.5 ng each MO. Scale bars = 50 μm.