秀丽隐杆线虫的不变细胞谱系允许明确分配每个细胞的身份,这提供了一个独特的机会来研究发育动力学,如细胞分裂的时间,基因表达的动力学,和单细胞分辨率下的细胞命运决定。然而,对细胞形态动力学知之甚少,包括它们在个体之间的变化程度,主要是由于缺乏足够数量和质量的量化数据。在这项研究中,我们系统地量化了52个C.elegans胚胎中的细胞形态动力学,从两细胞阶段到中期的高时空分辨率,光学截面厚度0.5μm,和30秒的录音间隔。我们的数据允许对形态特征进行系统分析。我们分析了球度动力学,发现每个细胞在中期结束时都显着增加,表明有丝分裂细胞变圆的普遍性。伴随着四舍五入,大多数但不是所有细胞的体积也增加了,表明有丝分裂肿胀的普遍性较小。结合所有特征表明,每种细胞类型的细胞形态动力学都是独特的。胃泌素开始之前的细胞可以与所有其他细胞类型区分开。细胞与细胞接触的可重复性的定量表明,分裂时间和细胞排列的变异性导致胚胎之间的接触变异性。然而,这种接触的面积占总面积的5%以下,表明细胞的空间占有率和邻接关系具有很高的可重复性。通过比较胚胎之间相同细胞的形态动力学,我们观察到细胞间变异性的多样性,发现它是由多种因素决定的,包括细胞谱系,细胞生成,和细胞-细胞接触。我们将细胞形态动力学和细胞间接触的变化与海鞘哺乳动物胚胎的变化进行了比较。秀丽隐杆线虫的变异更大,尽管在每个发育阶段胚胎大小和细胞数量的差异较小。
The invariant cell lineage of Caenorhabditis elegans allows unambiguous assignment of the identity for each cell, which offers a unique opportunity to study developmental dynamics such as the timing of cell division, dynamics of gene expression, and cell fate decisions at single-cell resolution. However, little is known about cell
morphodynamics, including the extent to which they are variable between individuals, mainly due to the lack of sufficient amount and quality of quantified data. In this study, we systematically quantified the cell
morphodynamics in 52 C. elegans embryos from the two-cell stage to mid-gastrulation at the high spatiotemporal resolution, 0.5 μm thickness of optical sections, and 30-second intervals of recordings. Our data allowed systematic analyses of the morphological features. We analyzed sphericity dynamics and found a significant increase at the end of metaphase in every cell, indicating the universality of the mitotic cell rounding. Concomitant with the rounding, the volume also increased in most but not all cells, suggesting less universality of the mitotic swelling. Combining all features showed that cell
morphodynamics was unique for each cell type. The cells before the onset of gastrulation could be distinguished from all the other cell types. Quantification of reproducibility in cell-cell contact revealed that variability in division timings and cell arrangements produced variability in contacts between the embryos. However, the area of such contacts occupied less than 5% of the total area, suggesting the high reproducibility of spatial occupancies and adjacency relationships of the cells. By comparing the
morphodynamics of identical cells between the embryos, we observed diversity in the variability between cells and found it was determined by multiple factors, including cell lineage, cell generation, and cell-cell contact. We compared the variabilities of cell
morphodynamics and cell-cell contacts with those in ascidian Phallusia mammillata embryos. The variabilities were larger in C. elegans, despite smaller differences in embryo size and number of cells at each developmental stage.