( A) Live confocal imaging time course of vacuole dynamics and morphology during spine development in WT zebrafish larvae. n = 3, 6, 11, 13. ( B) Live confocal imaging time course of vacuole dynamics and morphology during spine development in spzl-/- larvae. n = 3, 4, 8, 7. ( A–B) Larvae express GFP in the cytoplasm of vacuolated cells and mCherry in osteoblasts. Note the progressive loss of vacuoles in spzl-/- and the straight notochord and spine prior to the onset of concentric vertebral growth. Dotted lines mark the edge of the notochord. Arrow points to a spine kink in spzl-/-. ( C) Maximum intensity projection of a laterally oriented 29 dpf spzl-/- larva. The spine is visualized by mCherry expression in the osteoblasts. ( D–E) Maximum intensity projections showing dorsal ( D) and lateral ( E) views of a 29 dpf spzl-/- larva expressing mCherry in the osteoblasts and GFP in the notochord. The anterior spine is straight while the posterior region has developed several spine kinks ( F) Optical confocal section of the straight anterior portion of the spine. Asterisks mark intact vacuoles. ( G–I) Optical confocal sections of the posterior notochord where vacuoles are highly fragmented or absent and the spine is highly kinked. Gt(SAGFF214A:gal4); Tg(UAS:GFP); Tg(osx:NTR-mCherry). Scale bars are 100 µm.
