Kopachik W
J Embryol Exp Morphol. 1982 Apr;68:23-35.
The division of large aggregate centres into separate slugs was examined in two strains of Dictyostelium discoideum which differ in size. The evidence is consistent with the hypothesis that the size of the slugs is determined by two factors; one is the ability of a tip to inhibit surrounding cells from forming an independent, rival tip; the other is the ability of the surrounding cells to resist being subjected to the inhibition of the newly arisen tip. If the surrounding cells are easily inhibited, then the slugs produced will be large; if they are resistant to inhibition the resulting slugs will be correspondingly small. An assay for tip inhibition was developed which was used to estimate the volume and distance over which inhibition occurs, the time over which it acts and the effect of tip size and cell mass shape on size regulation. The measurements and the results of experiments which showed inhibition across a thin agar layer are consistent with the hypothesis that an inhibitor spreads out from the tip by simple diffusion. In further studies it was found that although inhibition strength varies with the size of the tip, the ability to inhibit was the same in both strains whereas the resistance to inhibition was greater in the smaller strain.
在两种大小不同的盘基网柄菌菌株中，研究了大型聚集中心分裂成独立蛞蝓体的情况。证据与以下假设一致：蛞蝓体的大小由两个因素决定；一个是顶端抑制周围细胞形成独立竞争顶端的能力；另一个是周围细胞抵抗新出现顶端抑制作用的能力。如果周围细胞容易被抑制，那么产生的蛞蝓体就会很大；如果它们对抑制有抗性，那么产生的蛞蝓体就会相应较小。开发了一种顶端抑制测定法，用于估计抑制发生的体积和距离、抑制作用的时间以及顶端大小和细胞团形状对大小调节的影响。测量结果以及显示穿过薄琼脂层的抑制作用的实验结果与以下假设一致：一种抑制剂通过简单扩散从顶端扩散开来。在进一步的研究中发现，尽管抑制强度随顶端大小而变化，但两种菌株的抑制能力相同，而较小菌株对抑制的抗性更大。
