Zaher Mira, Yelin Ronit, Arraf Alaa A, Jadon Julian, Asleh Manar Abboud, Goltzman Sivan, Shaulov Lihi, Reinhardt Dieter P, Schultheiss Thomas M
Department of Genetics and Developmental Biology, Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa 31096, Israel.
Faculty of Medicine and Health Sciences, McGill University, Montreal, QC H3A 0C7, Canada; Faculty of Dental Medicine and Oral Health Sciences, McGill University, Montreal, QC H3A 0C7, Canada.
Cell Rep. 2025 Jan 28;44(1):115200. doi: 10.1016/j.celrep.2024.115200. Epub 2025 Jan 10.
During development, amniote vertebrate embryos transform from a flat sheet into a three-dimensional cylindrical form through ventral folding of the lateral sides of the sheet (the lateral plate [LP]) and their fusion in the ventral midline. Using a chick embryo slice system, we find that the flat stage is actually a poised balance of opposing dorsal and ventral elastic bending tensions. An intact extracellular matrix (ECM) is required for generating tension, as localized digestion of ECM dissipates tension, while removal of endoderm or ectoderm layers has no significant effect. As development proceeds, dorsal bending tension dissipates coincident with epithelial-mesenchymal transition in the dorsal LP while ventral tension is maintained, changing the balance of forces to promote ventral folding. Interference with the elastic ECM component fibrillin reduces ventral bending tension and perturbs body folding in vivo. A model is presented for the accumulation and harnessing of LP bending tension to drive body folding.
在发育过程中，羊膜动物脊椎动物胚胎通过胚盘两侧（侧板[LP]）的腹侧折叠并在腹侧中线融合，从扁平薄片转变为三维圆柱形态。利用鸡胚切片系统，我们发现扁平阶段实际上是背侧和腹侧弹性弯曲张力相互对立的一种平衡状态。产生张力需要完整的细胞外基质（ECM），因为ECM的局部消化会使张力消散，而去除内胚层或外胚层则没有显著影响。随着发育的进行，背侧弯曲张力随着背侧LP中的上皮-间充质转化而消散，而腹侧张力得以维持，从而改变力的平衡以促进腹侧折叠。干扰弹性ECM成分原纤蛋白会降低腹侧弯曲张力并扰乱体内的身体折叠。本文提出了一个关于积累和利用LP弯曲张力来驱动身体折叠的模型。
