Pinching and pushing: fold formation in the Drosophila dorsal epidermis
Pinching and pushing: fold formation in the Drosophila dorsal epidermis
复制标题
捏和推：果蝇背表皮的褶皱形成
DOI：
10.1016/j.bpj.2021.08.028
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发表时间：
2021
影响因子：
3.4
通讯作者：
Zartman, Jeremiah J.
中科院分区：
文献类型：
--
作者：
Velagala, Vijay;Zartman, Jeremiah J.
上皮折叠是一个基本的形态发生过程，它将平面的上皮片层塑造成复杂的三维结构。多种机制可以产生上皮褶皱，包括在细胞水平局部作用的顶端收缩、组织规模上的差异生长或由于邻近组织的压缩而屈曲。在这里，我们研究了在果蝇胚胎发生的后期阶段，在体节边界处的背侧上皮褶皱的形成。我们发现，在段边界处的褶皱形成通过两个关键的形态发生过程的并置发生：局部顶端收缩和来自后段的组织水平的压缩力。此外，我们发现，表皮扩展和褶皱的形成伴随着时空脉冲的刺猬（Hh）信号。一个计算模型，它结合了从不同的张力的顶端，基底，和细胞的侧面和整个组织内产生的主动力的局部力概括了整个折叠形成过程中的野生型和Hh过表达条件。总之，这项工作证明了上皮折叠如何依赖于多个，可分离的物理机制，以产生最终形态的背表皮。这项工作说明了上皮形态发生过程中发生的形态发生单位操作的模块性。
Epithelial folding is a fundamental morphogenetic process that shapes planar epithelial sheets into complex three-dimensional structures. Multiple mechanisms can generate epithelial folds, including apical constriction, which acts locally at the cellular level, differential growth on the tissue scale, or buckling because of compression from neighboring tissues. Here, we investigate the formation of dorsally located epithelial folds at segment boundaries during the late stages ofDrosophilaembryogenesis. We found that the fold formation at the segment boundaries occurs through the juxtaposition of two key morphogenetic processes: local apical constriction and tissue-level compressive forces from posterior segments. Further, we found that epidermal spreading and fold formation are accompanied by spatiotemporal pulses of Hedgehog (Hh) signaling. A computational model that incorporates the local forces generated from the differential tensions of the apical, basal, and lateral sides of the cell and active forces generated within the whole tissue recapitulates the overall fold formation process in wild-type and Hh overexpression conditions. In sum, this work demonstrates how epithelial folding depends on multiple, separable physical mechanisms to generate the final morphology of the dorsal epidermis. This work illustrates the modularity of morphogenetic unit operations that occur during epithelial morphogenesis.