Research Article

Obscurin Depletion Impairs Organization of Skeletal Muscle in Developing Zebrafish Embryos

Figure 6

Overlapping localization of talin and vinculin during early skeletal muscle development. Control (a), (b), (e), (h)–(j) and obscurin A morphant (c), (d), (f), (g), (k)–(m) embryos were immunostained for talin ((a)–(g): green) and laminin ((b), (d): red) or vinculin ((h)–(m): green) at 24 (a)–(h), (k), 48 (i), (l), or 72 (j), (m) hpf. (a) In a control embryo, talin localizes to the MTJ and overlying the myofibrils at 24 hpf. (b) At the MTJ, talin localizes immediately adjacent to laminin. (c), (d) In obscurin A morphant embryos at 24 hpf, talin does localize to the irregularly organized MTJs but there are regions in which laminin has been deposited where talin has not yet accumulated (arrow). (e), (f) In control and obscurin A morphant embryos, talin localizes overlying the Z disk (arrowheads) although there are regions of diffuse talin localization in the morphant (asterisk) that were not noted in the control. (g) In newly forming myofibrils talin localizes along the myofibril (arrowhead) before achieving a striated pattern overlying the Z disk. No talin localization was noted overlying the mid-A-band. (h), (k) Like talin, vinculin localized to the somite boundary/MTJ ((h): arrowhead) at 24 hpf in both control (h) and morphant (k) embryos. (i), (l), (j), (m) By 48 hpf, there is progressive accumulation of vinculin at the MTJ in control (i) and morphant (l) embryos with nearly exclusive localization to the MTJ by 72 hpf in both control (j) and morphant (m) embryos. Scale bars are 50 μm. Panels (e)–(g) are 3x magnifications of the corresponding regions of (a), (c), and (d).
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