Department of Biology, Indiana University, Bloomington, IN 47405, USA.
Development. 2023 Sep 15;150(18). doi: 10.1242/dev.201872. Epub 2023 Sep 25.
A fundamental goal of developmental biology is to understand how cell and tissue fates are specified. The imaginal discs of Drosophila are excellent model systems for addressing this paradigm as their fate can be redirected when discs regenerate after injury or when key selector genes are misregulated. Here, we show that when Polycomb expression is reduced, the wing selector gene vestigial is ectopically activated. This leads to the inappropriate formation of the Vestigial-Scalloped complex, which forces the eye to transform into a wing. We further demonstrate that disrupting this complex does not simply block wing formation or restore eye development. Instead, immunohistochemistry and high-throughput genomic analysis show that the eye-antennal disc unexpectedly undergoes hyperplastic growth with multiple domains being organized into other imaginal discs and tissues. These findings provide insight into the complex developmental landscape that tissues must navigate before adopting their final fate.
发育生物学的一个基本目标是了解细胞和组织命运是如何被指定的。果蝇的 imaginal discs 是解决这一范例的极好模型系统，因为当 discs 在受伤后再生或关键选择基因被错误调节时，它们的命运可以被重新引导。在这里，我们表明，当 Polycomb 表达降低时，翅选择基因 vestigial 被异位激活。这导致了 Vestigial-Scalloped 复合物的不适当形成，从而迫使眼睛转变成翅膀。我们进一步证明，破坏这个复合物并不能简单地阻止翅膀的形成或恢复眼睛的发育。相反，免疫组织化学和高通量基因组分析表明，眼触角盘出人意料地经历了过度生长，多个区域被组织成其他 imaginal discs 和组织。这些发现为组织在采用最终命运之前必须经历的复杂发育景观提供了深入了解。
