Darmon M, Brachet P, Da Silva L H
Proc Natl Acad Sci U S A. 1975 Aug;72(8):3163-6. doi: 10.1073/pnas.72.8.3163.
Experiments carried out with the aid of cellophane membranes demonstrate that the morphogenetic block of certain nonaggregating, "aggregateless," mutants may be overcome by diffusible factors excreted by aggregating wild-type cells. The same differentiation process into aggregation-competent cell is observed if mutant amoebae are subjected to external 3':5'-cAMP pulses imposed at 5 min intervals. Wild-type amoebae also respond to cAMP pulses, since the onset of differentiation is more precocious in pulsed than in unpulsed populations. These data suggest that chemotactic signals act as an inducer of cell differentiation.
借助玻璃纸膜进行的实验表明，某些非聚集性“无聚集能力”突变体的形态发生阻滞可被聚集性野生型细胞分泌的可扩散因子克服。如果对突变变形虫每隔5分钟施加一次外部3':5'-环磷酸腺苷脉冲，会观察到其向具有聚集能力的细胞的相同分化过程。野生型变形虫也对环磷酸腺苷脉冲有反应，因为在脉冲处理的群体中，分化的开始比未处理的群体更早。这些数据表明趋化信号作为细胞分化的诱导剂。
