Ferguson D J, Birch-Andersen A, Siim J C, Hutchison W M
Acta Pathol Microbiol Scand B. 1979 Jun;87B(3):171-81. doi: 10.1111/j.1699-0463.1979.tb02422.x.
The initial stages of sporulation in oocysts of Toxoplasma gondii were examined in samples sporulated at 27 degrees C for 0, 6, 12, 16 and 24 hours. The initial zygote was roughly spherical and was limited by a single unit membrane. A few micropores of the inactive type were present on this membrane. The cytoplasm contained a large nucleus with a nucleolus, a number of polysaccharide granules, lipid globules, mitochondria, and Golgi bodies together with a few strands of rough endoplasmic reticulum. After the initiation of sporulation little change was noted in the cytoplasm except for an increase in protein synthesis as evidenced by the augmentation of the amount of rough endoplasmic reticulum and the appearance of polyribosomes. Nuclear division occurred twice giving rise to four nuclei which were situated close to the cell periphery and well separated from each other. At this multinucleate stage a second limiting membrane was formed. The cytoplasmic mass then divided to form the two sporoblasts. This was accomplished by an invagination of the limiting membranes in combination with internally formed membranes. The two binuclear sporoblasts were roughly spherical. They were limited by two unit membranes and contained the same cytoplasmic organelles as described for the zygote.
在27摄氏度下分别培养0、6、12、16和24小时的样本中，对刚地弓形虫卵囊孢子化的初始阶段进行了研究。最初的合子大致呈球形，由单层单位膜包被。该膜上有一些非活性类型的微孔。细胞质中含有一个带有核仁的大细胞核、一些多糖颗粒、脂滴、线粒体、高尔基体以及几缕粗面内质网。孢子化开始后，除了粗面内质网数量增加和多聚核糖体出现表明蛋白质合成增加外，细胞质中未观察到明显变化。核分裂发生两次，产生四个位于细胞周边且彼此分隔良好的细胞核。在这个多核阶段，形成了第二个限制膜。然后细胞质团分裂形成两个子孢子母细胞。这是通过限制膜的内陷与内部形成的膜相结合来完成的。两个双核子孢子母细胞大致呈球形。它们由两层单位膜包被，含有与合子中描述的相同的细胞质细胞器。
