Obscurin Depletion Impairs Organization of Skeletal Muscle in Developing Zebrafish Embryos
Figure 1
Obscurin A depletion results in abnormalities of myotome development. (a, b) Compared to control embryos at 20 hpf, an obscurin-A-depleted embryo (ObsMO) demonstrates shortening of the tail and indistinct somite boundaries. The skeletal muscle abnormalities are associated with irregularities of cell morphology as noted by cell membrane localization of lyn-GFP (c, d). Note that in control embryos, (c) lyn-GFP accumulates at the somite boundary (arrowheads). In morphant embryos (d), distinct somite boundaries are difficult to identify. (e–j) RNA in situ hybridization using riboprobes for MyoD, Notch5, and Notch6 in control (e)–(i) and obscurin A (f), (h), (j) morphant embryos demonstrate maintained expression but diminished periodicity of these somite markers suggesting preserved myocyte commitment but impaired somite organization in the setting of obscurin depletion. Scale bars are 50 μm (a)–(d) and 500 μm (e)–(j).
