小柯机器人

法国蒙彼利埃大学Patrick Lemaire、Christophe Godin、法国图卢兹第一和第三大学Grégoire Malandain和德国欧洲分子生物学实验室Lars Hufnagel团队合作取得一项新成果。经过不懈努力，他们揭示了接触依赖性细胞通讯和海鞘胚胎发育形态学的不变性。该研究于2020年7月10日发表于《科学》杂志。

研究人员揭示了海鞘胚胎可再现性的诱导因素。使用光片成像和自动细胞分割和跟踪程序，研究人员系统地量化了海鞘胚胎发育期间单个细胞每两分钟的行为。研究人员观察到个体细胞接触区域之间的个体可再现性。研究人员发现胚胎几何形状的可复制性与不对称细胞分裂之间的紧密联系受分化姐妹细胞诱导的调控。

利用建模和实验操作相结合的方法，研究人员证明信号传导和响应细胞之间的接触面积是细胞通讯的关键决定因素。该工作建立了胚胎诱导的几何控制以替代经典形态发生子梯度，并证明细胞信号传导的范围决定了胚胎可再现性的范围 。

据悉，海洋无脊椎动物海鞘显示出胚胎的可再现性，尽管海鞘基因组多变，但它们的早期胚胎细胞谱系被认为是不变的，并且在远缘物种之间也是保守的。

附：英文原文

Title: Contact area–dependent cell communication and the morphological invariance of ascidian embryogenesis

Author: Léo Guignard, Ulla-Maj Fiúza, Bruno Leggio, Julien Laussu, Emmanuel Faure, Gal Michelin, Kilian Biasuz, Lars Hufnagel, Grégoire Malandain, Christophe Godin, Patrick Lemaire

Issue&Volume: 2020/07/10

Abstract: Marine invertebrate ascidians display embryonic reproducibility: Their early embryonic cell lineages are considered invariant and are conserved between distantly related species, despite rapid genomic divergence. Here, we address the drivers of this reproducibility. We used light-sheet imaging and automated cell segmentation and tracking procedures to systematically quantify the behavior of individual cells every 2 minutes during Phallusia mammillata embryogenesis. Interindividual reproducibility was observed down to the area of individual cell contacts. We found tight links between the reproducibility of embryonic geometries and asymmetric cell divisions, controlled by differential sister cell inductions. We combined modeling and experimental manipulations to show that the area of contact between signaling and responding cells is a key determinant of cell communication. Our work establishes the geometric control of embryonic inductions as an alternative to classical morphogen gradients and suggests that the range of cell signaling sets the scale at which embryonic reproducibility is observed.

DOI: 10.1126/science.aar5663

Source: https://science.sciencemag.org/content/369/6500/eaar5663