Araki T, Abe T, Williams J G, Maeda Y
Biological Institute, Graduate School of Science, Tohoku University, Sendai, Japan.
Dev Biol. 1997 Dec 15;192(2):645-8. doi: 10.1006/dbio.1997.8784.
The event that visibly breaks the symmetry of the Dictyostelium aggregate is the formation of a nipple-shaped tip at its apex, but there has been considerable debate as to the equivalence of cells entering development, particularly with regard to the effect of cell cycle position at the onset of starvation. We show that there is a strong correlation between cell cycle position at the time of starvation and the subsequent expression of a marker of tip cell differentiation. Cells starved in late-G2 phase selectively differentiate into tip cells. Previous evidence indicated that tip cells differentiate at the extreme periphery of the aggregate and then move to the apex. Taken in combination, these data suggest that cell cycle position at the onset of starvation affects differentiation fate by determining a cell's probable position within the aggregate, i.e., that both cell cycle and positional information are used to generate pattern.
明显打破盘基网柄菌聚集体对称性的事件是在其顶点形成乳头状尖端，但关于进入发育阶段的细胞是否等同，尤其是饥饿开始时细胞周期位置的影响，一直存在相当大的争议。我们表明，饥饿时的细胞周期位置与随后尖端细胞分化标志物的表达之间存在很强的相关性。在G2晚期饥饿的细胞选择性地分化为尖端细胞。先前的证据表明，尖端细胞在聚集体的最外围分化，然后移动到顶点。综合来看，这些数据表明，饥饿开始时的细胞周期位置通过确定细胞在聚集体中的可能位置来影响分化命运，即细胞周期和位置信息都用于产生模式。
