Department of Evolutionary Biology, University of Siena, Via A. Moro 2, I-53100 Siena, Italy.
Tissue Cell. 2010 Apr;42(2):97-104. doi: 10.1016/j.tice.2010.01.001. Epub 2010 Feb 9.
The general organization of the male genital system, the spermatogenesis and the sperm structure of the proturan Acerella muscorum have been described. At the apex of testis apical huge cells are present; their cytoplasm contains a conventional centriole, a large amount of dense material and several less electron-dense masses surrounded by mitochondria. Spermatocytes have normal centrioles and are interconnected by cytoplasmic bridges. Such bridges seem to be absent between spermatid cells and justify the lack of synchronization of cell maturation. Spermatids are almost globular cells with a spheroidal nucleus and a large mass of dense material corresponding to the centriole adjunct. Within this mass a centriole is preserved. Mitochondria of normal structure are located between the nucleus and the plasma membrane. The spermatids are surrounded by a thick membrane. No flagellar structure is formed. Sperm have a compact spheroidal nucleus, a large cap of centriole adjunct material within which a centriole is still visible. A layer of mitochondria is located over the nucleus. The cytoplasm is reduced in comparison to spermatids; many dense bodies are interspersed with sperm in the testicular lumen. The sperm are small, immotile cells of about 2.5-3microm in diameter.
已描述了原尾目 Acerella muscorum 的雄性生殖系统的一般组织、精子发生和精子结构。在睾丸顶端存在巨大的顶端细胞；它们的细胞质含有一个常规的中心粒、大量密集物质和几个被线粒体包围的电子密度较低的物质。精母细胞具有正常的中心粒，并通过细胞质桥相互连接。精细胞之间似乎没有这种桥，这证明了细胞成熟的不同步。精细胞几乎是球形细胞，具有球形核和大量的密集物质，对应于中心粒附属物。在这个物质团中保留了一个中心粒。结构正常的线粒体位于核和质膜之间。精细胞被一层厚膜包围。没有形成鞭毛结构。精子具有一个紧密的球形核，中心粒附属物的大帽内仍然可以看到一个中心粒。一层线粒体位于核上。与精细胞相比，细胞质减少；在睾丸管腔中，许多致密体与精子混合。精子是小的、不动的细胞，直径约为 2.5-3 微米。
