The ability of sponge cells to reaggregate and reconstruct intact functional organism is known for more than 100 years. This process was studied in numerous species of sponges, and its interspecific variability is well described. However, some data also indicate the existence of a certain intraspecific variability of the cell reaggregation. The present study deals with the cell reaggregation in two demosponges, Halichondria panicea and Halisarca dujardinii, during different periods of their sexual reproduction. In both species, cell reaggregation shows a common pattern at all studied periods of reproduction. However, the course of the reaggregation process significantly depends on the reproduction period of an individual used in the experiment, thus demonstrating pronounced intraspecific variability, which concerns the rate of the cell reaggregation and the final stage of the process. This variability occurs due to tissue rearrangements that accompany reproduction and changes cell composition and amount of available somatic stem cells in sponge tissues, and consequently alters morphogenetic potencies of a cell suspension and multicellular aggregates. In both Halichondria panicea and Halisarca dujardinii, the growth period is the most favorable for the reaggregation process, while the cell reaggregation is depressed during periods of embryogenesis and restoration of somatic tissues after the reproduction. At the same time, the structure of a particular stage of reaggregation and morphogenetic processes underlying the development of multicellular aggregates are always identical, independently from the period of the reproductive cycle.

中文翻译：

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海绵繁殖周期中细胞重新聚集的种内变异性

海绵细胞重新聚集和重建完整功能有机体的能力已为人们所知 100 多年。在许多种类的海绵中研究了这个过程，并且很好地描述了它的种间变异性。然而，一些数据也表明细胞重新聚集存在一定的种内变异性。本研究涉及在两种有性繁殖的不同时期，Halichondria panicea 和 Halisarca dujardinii 中的细胞重新聚集。在这两个物种中，细胞重新聚集在所有研究的繁殖时期都显示出共同的模式。然而，重新聚集过程的进程在很大程度上取决于实验中使用的个体的繁殖期，因此证明了明显的种内变异性，这涉及细胞重新聚集的速度和过程的最后阶段。这种变异性的发生是由于伴随繁殖和改变细胞组成和海绵组织中可用体干细胞数量的组织重排，从而改变细胞悬液和多细胞聚集体的形态发生潜能。在Halichondria panicea和Halisarca dujardinii中，生长期最有利于重新聚集过程，而在胚胎发生和繁殖后体细胞组织恢复期间细胞重新聚集受到抑制。同时，多细胞聚集体发育的特定阶段的结构和形态发生过程总是相同的，独立于生殖周期的时期。