Biology Department, Boston College, Chestnut Hill, MA 02467, USA.
Biology Department, Boston College, Chestnut Hill, MA 02467, USA.
Cell Rep. 2021 Oct 12;37(2):109827. doi: 10.1016/j.celrep.2021.109827.
Polyploidy frequently arises in response to injury, aging, and disease. Despite its prevalence, major gaps exist in our understanding of how polyploid cells alter tissue function. In the adult Drosophila epithelium, wound healing is dependent on the generation of multinucleated polyploid cells resulting in a permanent change in the epithelial architecture. Here, we study how the wound-induced polyploid cells affect tissue function by altering epithelial mechanics. The mechanosensor nonmuscle myosin II is activated and upregulated in wound-induced polyploid cells and persists after healing completes. Polyploidy enhances relative epithelial tension, which is dependent on the endocycle and not cell fusion post injury. Remarkably, the enhanced epithelial tension mimics the relative tension of the lateral muscle fibers, which are permanently severed by the injury. As a result, we found that the wound-induced polyploid cells remodel the epithelium to maintain fly abdominal movements, which may help compensate for lost tissue tension.
多倍体经常因损伤、衰老和疾病而产生。尽管多倍体很常见，但我们对多倍体细胞如何改变组织功能的理解还存在很大的差距。在成年果蝇的上皮组织中，伤口愈合依赖于多核多倍体细胞的产生，导致上皮结构发生永久性变化。在这里，我们通过改变上皮力学来研究诱导多倍体细胞如何影响组织功能。机械感受器非肌肉肌球蛋白 II 在诱导多倍体细胞中被激活和上调，并在愈合完成后持续存在。多倍体增加了相对上皮张力，这依赖于内循环，而不是损伤后的细胞融合。值得注意的是，增强的上皮张力模拟了横向肌纤维的相对张力，这些肌纤维在损伤中被永久性切断。因此，我们发现诱导多倍体细胞重塑上皮组织以维持果蝇腹部运动，这可能有助于补偿失去的组织张力。
