| Full text | |
| Author(s): |
Total Authors: 3
|
| Affiliation: | [1] Universidade Estadual Paulista. Instituto de Biociências, Letras e Ciências Exatas. Programa de Pós-graduação em Biologia Animal - Brasil
[2] Universidade Estadual Paulista. Departamento de Biologia - Brasil
[3] Universidade Estadual Paulista. Departamento de Biologia - Brasil
Total Affiliations: 3
|
| Document type: | Journal article |
| Source: | IHERINGIA SERIE ZOOLOGIA; v. 98, n. 2, p. 193-199, 2008-06-00. |
| Abstract | |
Spermatozoon maturation involves an extense and complex process beginning with proliferation and differentiation of spermatogonia, passing through meiosis, and ending with spermiogenesis. The later event involves morphological and biochemical changes in order to transform spermatids into spermatozoa. Ultrastructural aspects of the spermiogenesis and testicular spermatozoa of the anuran Eupemphix nattereri (Steindachner, 1863) were analyzed by transmission electron microscopy. Spermiogenesis involves chromatin condensation and nuclear elongation, with visible cytoplasmic elimination. At this stage, a large amount of microtubules and glycogen can also be seen in Sertoli cell cytoplasm, surrounding each spermatid. The spermatozoon is fusiform and the acrossome forms a cap in the anterior region of the nucleus. A mitochondrial sleeve is found around the proximal portion of the tail. The tail presents an axonema with a 9+2 pattern, a justaxonemal fiber, an undulating membrane, and the absence of axial rod. This organization shows some similarities with species of the genus Physalaemus (Leiuperidae) such as P. biligonigerus (Cope, 1861), P. gracilis (Boulenger, 1883) and P. fuscomaculatus (Steindachner, 1864). (AU) | |
| FAPESP's process: | 05/02919-5 - Comparative analyses and anatomy of extracutaneous pigmentary system in Leptodactylidae (Anura): structural biology of the melanocytes associated with masculine reproductive system |
| Grantee: | Classius de Oliveira |
| Support Opportunities: | Regular Research Grants |