ACRASIN, ACRASINASE, AND SENSITIVITY TO ACRASIN DICTYOSTELIUM DISCOIDEUM
ACRASIN, ACRASINASE, AND SENSITIVITY TO ACRASIN DICTYOSTELIUM DISCOIDEUM
复制标题
DOI：
10.1016/0012-1606(69)90005-0
复制
发表时间：
1969-01-01
影响因子：
2.7
通讯作者：
WOLFE, PB
中科院分区：
文献类型：
--
作者：
BONNER, JT;BARKLEY, DS;WOLFE, PB
本研究的目的是研究在正常发育的acras（环AMP）和acras酶（磷酸二酯酶）和acras在细胞黏菌Dictyosteelium discoideum.Phosphodiesterase的敏感性分泌的营养，聚集和迁移阶段的正常发展的作用。目前还不清楚环AMP是否是由营养阿米巴产生的，但在聚集的开始和晚期聚集之间有100倍的增加，在迁移过程中下降到较低的水平。在聚集过程中，对环AMP的敏感性也增加了100倍，因此趋化系统在聚集过程中的作用至少是营养阶段的104倍。这些实验结果表明：（1）磷酸二酯酶在制作陡梯度中的重要性（并提供各种acras测定的基础），（2）陡梯度的环AMP在产生细胞增殖和可能的抑制中心中的作用;（3）高浓度的外部应用的cyclic-AMP的中心诱导能力。假定在正常聚集之前，影响聚集的化学物质的分布是均匀的，并且这种平衡被某些细胞对环AMP的突然过度敏感性及其产生以及阻止邻近细胞具有这种增加所破坏。通过趋化作用，结果是细胞的不均匀分布，最终达到一个新的稳定状态，在这种状态下，它们以非随机间隔的群体聚集在基质表面上。
The purpose of this study was to examine the role in normal development of an acrasin (cyclic-AMP) and of an acrasinase (phophodiesterase) and the sensitivity to acrasin in the cellular slime moldDictyostelium discoideum.Phosphodiesterase is secreted throughout the vegetative, aggregation, and migration stages. It is unclear whether or not cyclic-AMP is produced by vegetative amoebae, but there is a 100-fold increase between the beginning of aggregation and late aggregation, falling to a lower level during migration. The sensitivity to cyclic-AMP also increases 100-fold during aggregation, therefore the chemotactic system is at least 104times more effective during aggregation than during the vegetative stage.Artificial patterns of amoebae may be produced by making an uneven distribution of cyclic-AMP in the agar with an even distribution of amoebae, or the reverse. The results of these experiments show: (1) the importance of phosphodiesterase in making steep gradients (and providing the basis of various acrasin assays), (2) the role of steep gradients of cyclic-AMP in producing cell adhesiveness, and possibly inhibiting centers; (3) the center-inducing capacity of a high concentration of externally applied cyclic-AMP.It is postulated that prior to normal aggregation, the distribution of chemicals affecting aggregation is homogeneous, and that this equilibrium is upset by sudden excessive sensitivity to cyclic-AMP and its production by certain cells, and the prevention of neighboring cells from having such an increase. The result, by chemotaxis, is an uneven distribution of cells which ultimately reach a new steady state in which they are massed together in groups spaced nonrandomly over the surface of the substratum.