标题： 黏菌变形虫中的自发中心形成 显示英文标题

标题： Spontaneous center formation in Dictyostelium discoideum

摘要： 粘菌（D.d.）是一种被广泛研究的阿米巴，因其具有发育、生存和自组织的能力。在聚集过程中，它会产生并传递一种化学信号（cAMP），这显示出螺旋和靶心结构。然而，这些结构的自然出现仍然没有被很好地理解。我们提出了一种机制，通过向一个已知的cAMP波反应-扩散模型中添加细胞不均匀性，来创建D.d.中的中心和靶波，并对其特性进行了表征。我们展示了稳定活动中心如何在细胞密度较高的区域自发出现，这些中心的振荡频率取决于它们的密度。cAMP波具有触发波的特征色散关系，并且其速度随着细胞密度的增加而增加。具有趋化能力的细胞会对这些波做出反应，并在非常简单的运动规则下形成聚集流。最后，我们论证了存在有限的磷酸二酯酶，以在出现小细胞簇后维持波的特性。 显示英文摘要

摘要： Dictyostelium discoideum (D.d.) is a widely studied amoeba due to its capabilities of development, survival, and self-organization. During aggregation it produces and relays a chemical signal (cAMP) which shows spirals and target centers. Nevertheless, the natural emergence of these structures is still not well understood. We present a mechanism for creation of centers and target waves of cAMP in D.d. by adding cell inhomogeneity to a well known reaction-diffusion model of cAMP waves and we characterize its properties. We show how stable activity centers appear spontaneously in areas of higher cell density with the oscillation frequency of these centers depending on their density. The cAMP waves have the characteristic dispersion relation of trigger waves and a velocity which increases with cell density. Chemotactically competent cells react to these waves and create aggregation streams even with very simple movement rules. Finally we argue in favor of the existence of bounded phosphodiesterase to maintain the wave properties once small cell clusters appear.