McAuley P J
J Cell Sci. 1982 Dec;58:423-31. doi: 10.1242/jcs.58.1.423.
In fed hydra or excised regenerating peduncles there are increases in the mitotic indices of both digestive cells and the symbiotic algae that reside within them. Conversely, algal and digestive cell mitotic indices decrease in starved hydra. The temporal relationships of algal and host cell division differ in fed hydra and regenerating peduncles. After feeding, algal and digestive cell mitotic indices both reach a peak at about the same time; during regeneration, first the algae and then the digestive cells divide. Thus, mitotic digestive cells in regenerating peduncles contain more algae than those in gastric regions of fed hydra. However, in both cases mitotic digestive cells contain more algae than non-mitotic cells. The algae appear to be partitioned at random between daughter digestive cells at teleophase. It is suggested that the division of the symbiotic algae is closely related to that of the digestive cells in which they maintained. Mitosis of algae is stimulated by host cell mitosis, but in non-dividing cells algal mitosis is restricted. Possible mechanisms by which the host digestive cells could restrict algal division are discussed.
在喂食后的水螅或切除后正在再生的柄部中，消化细胞以及存在于其中的共生藻类的有丝分裂指数均会增加。相反，饥饿的水螅中藻类和消化细胞的有丝分裂指数会降低。在喂食后的水螅和正在再生的柄部中，藻类和宿主细胞分裂的时间关系有所不同。喂食后，藻类和消化细胞的有丝分裂指数大约在同一时间达到峰值；在再生过程中，先是藻类然后是消化细胞进行分裂。因此，正在再生的柄部中的有丝分裂消化细胞比喂食后的水螅胃区中的有丝分裂消化细胞含有更多的藻类。然而，在这两种情况下，有丝分裂的消化细胞都比非有丝分裂细胞含有更多的藻类。在末期，藻类似乎是随机分配到子代消化细胞中的。有人认为共生藻类的分裂与它们所寄生的消化细胞的分裂密切相关。宿主细胞的有丝分裂会刺激藻类的有丝分裂，但在不分裂的细胞中，藻类的有丝分裂受到限制。文中讨论了宿主消化细胞限制藻类分裂的可能机制。
