Knockdown of MyBPC expression in 4-dpf larvae. (A) A 2% agarose gel separation of standard (lane a) and of PCR products using primers for mybpc-2b (lanes b–e). Two samples from each condition were run in parallel in separate lanes. Samples from control-injected larvae are shown in lane b. Lanes c–e show results from larvae injected with splicing blocking MOs for mybpc-1, mybpc-2a, and mybpc-2b (∼4 ng), respectively. The arrow indicates the main PCR product for mybpc-2b (371 bp). The dashed arrow shows an extra PCR product (238 bp) for mybpc-2b generated by the splicing MOs. (B) Corresponding PCR products from the same larval materials, using primers for β-actin. Each lane was loaded with extracts from a single larva. The bands in the standards (lane a) in A and B were from above: 506 (not visible in B), 396, 344, 298, 220, and 201 bp. (C) Western blot of protein extracts from the trunk muscles of control and splicing and translational blocking MyBPC-2 morphants (lanes from left to right). The MyBPC-2 bands (molecular mass ∼130 kD) are shown in the top and the corresponding GAPDH bands (molecular mass around 40 kD) in the bottom blots. (D) Summarized data for mybpc-2b mRNA expression in control-injected larvae (open bar) and larvae injected with MO for mybpc-1 (hatched bar), mybpc-2a (gray bar), and mybpc-2b (black bar); n = 2–4. (E) qPCR data for MyBPC-1 expression in control-injected larvae (open bar) and larvae injected with MO for mybpc-1 (hatched bar) and mybpc-2b (black bar); n = 4. Results from statistical analysis (ANOVA) are indicated in the figure: *, P < 0.05; **, P < 0.01; ***, P < 0.001. Data are presented as mean ± SEM.