Saunders Dillan, Camacho-Macorra Carlos, Steventon Benjamin
Department of Genetics, University of Cambridge, Cambridge, UK, CB2 3EH.
Development. 2025 Jan 1;152(1). doi: 10.1242/dev.204438. Epub 2025 Jan 9.
Early embryos display a remarkable ability to regulate tissue patterning in response to changes in tissue size. However, it is not clear whether this ability continues into post-gastrulation stages. Here, we performed targeted removal of dorsal progenitors in the zebrafish tailbud using multiphoton ablation. This led to a proportional reduction in the length of the spinal cord and paraxial mesoderm in the tail, revealing a capacity for the regulation of tissue morphogenesis during tail formation. Following analysis of cell proliferation, gene expression, signalling and cell movements, we found no evidence of cell fate switching from mesoderm to neural fate to compensate for neural progenitor loss. Furthermore, tail paraxial mesoderm length is not reduced upon direct removal of an equivalent number of mesoderm progenitors, ruling out the hypothesis that neuromesodermal competent cells enable proportional regulation. Instead, reduction in cell number across the spinal cord reduces both spinal cord and paraxial mesoderm length. We conclude that spinal cord elongation is a driver of paraxial mesoderm elongation in the zebrafish tail and that this can explain proportional regulation upon neural progenitor reduction.
早期胚胎表现出一种非凡的能力，能够根据组织大小的变化来调节组织模式。然而，目前尚不清楚这种能力是否会持续到原肠胚形成后的阶段。在这里，我们使用多光子消融技术在斑马鱼尾芽中靶向去除背侧祖细胞。这导致尾巴中脊髓和体节中胚层的长度成比例减少，揭示了尾巴形成过程中组织形态发生的调节能力。在对细胞增殖、基因表达、信号传导和细胞运动进行分析后，我们没有发现细胞命运从间充质转变为神经命运以补偿神经祖细胞损失的证据。此外，直接去除等量的中胚层祖细胞后，尾巴体节中胚层的长度并没有减少，排除了神经中胚层能干细胞实现比例调节的假设。相反，整个脊髓中细胞数量的减少会同时降低脊髓和体节中胚层的长度。我们得出结论，脊髓伸长是斑马鱼尾巴中体节中胚层伸长的驱动力，这可以解释神经祖细胞减少后的比例调节。
