Fig. 4.

Fig. 4.

Musculoskeletal defects in hnrnpul1/1l mutant fins. a, b) Fin muscle, as highlighted by MF20 staining for myosin heavy chain (MyHC) in wild type (a, b) and hnrnpul1/1l mutant (a’, b’) fins at 72 hpf. Scale bar = 50 μm. c–f) Alcian blue (cartilage) and alarizin red (bone) staining. c, c’) At early stages (40 dpf, SL = 6.2–6.7 mm) 2 CSZs are present in both wild type and hnrnpul1/1l mutant fins (arrowheads, scale bars = 50 μm). d, d’) At larval stages (40 dpf, SL = 11 mm) there are 4 proximal radial precursors in wild-type fins, but 3 proximal radial precursors in hnrnpul1/1l mutant fins (arrowheads; scale bars = 100 μm). e, f’) In adult fish (3-month old), alizarin red staining fluorescent imaged (e, e’) or brightfield imaged (f, f’) shows a missing proximal radial (pr4) and distal radial 7 (dr7) in a hnrnpul1/1l mutant. Scale bars are 200 µm. g) Quantification of the frequency of missing proximal and distal radials in adults (n = 12 wild type, 14 hnrnpul1/1l mutants). h) Quantification of the frequency of fins with the indicated number of rays per fin (n = 14 wild type, 13 hnrnpul1/1l mutant, P < 0.074, chi-squared test).