PDF(Pubmed)
Abstract：
The social amoeba Dictyostelium discoideum switches between solitary growth and social fruitification depending on nutrient availability. Under starvation, cells aggregate and form fruiting bodies consisting of spores and altruistic stalk cells. Once cells socially committed, they complete fruitification, even if a new source of nutrients becomes available. This social commitment is puzzling because it hinders individual cells from resuming solitary growth quickly. One idea posits that traits that facilitate premature de-commitment are hindered from being selected. We studied outcomes of the premature de-commitment through forced refeeding. Our results show that when refed cells interacted with non-refed cells, some of them became solitary, whereas a fraction was redirected to the altruistic stalk, regardless of their original fate. The refed cells exhibited reduced cohesiveness and were sorted out during morphogenesis. Our findings provide an insight into a division of labor of the social amoeba, in which less cohesive individuals become altruists.
摘要：
社会变形虫盘基网柄菌根据养分的可用性在孤立生长和社会果实化之间切换。在饥饿之下，细胞聚集并形成由孢子和利他茎细胞组成的子实体。一旦细胞社交化，他们完成了果实化，即使有新的营养来源。这种社会承诺令人困惑，因为它阻碍了单个细胞迅速恢复孤立生长。一种观点认为，阻碍人们选择促进过早放弃承诺的特征。我们研究了通过强制重新喂养过早减少承诺的结果。我们的结果表明，当重新标记的细胞与非重新标记的细胞相互作用时，他们中的一些人变得孤独，而一小部分被重定向到利他主义的茎，不管他们最初的命运。重新标记的细胞表现出降低的粘结性，并在形态发生过程中被分选。我们的发现为社会变形虫的分工提供了见解，在这种情况下，凝聚力较低的人成为利他主义者。
