title: Nucleolar cycle and chromatoid body formation: is there a relationship between these two processes during spermatogenesis of Dendropsophus minutus (Amphibia, Anura)?
abstract: The goals of this study were to monitor the nucleolar material distribution during Dendropsophus minutus spermatogenesis using cytological and cytochemical techniques and ultrastructural analysis, as well as to compare the nucleolar material distribution to the formation of the chromatoid body (CB) in the germ epithelium of this amphibian species. Nucleolar fragmentation occurred during the pachytene of prophase I and nucleolus reorganization occurred in the early spermatid nucleus. The area of the spermatogonia nucleolus was significantly larger than that of the earlier spermatid nucleolus. Ultrastructural analysis showed an accumulation of nuages in the spermatogonia cytoplasm, which form the CB before nucleolar fragmentation. The CB was observed in association with mitochondrial clusters in the cytoplasm of primary spermatocytes, as well as in those of earlier spermatids. In conclusion, the nucleolus seems to be related to CB formation during spermatogenesis of D. minutus, because, at the moment of nucleolus fragmentation in the primary spermatocytes, the CB area reaches a considerable size and is able to execute its important functions during spermatogenesis. The reorganized nucleolus of the earlier spermatids has a smaller area due to several factors, among them the probable migration of nucleolar fragments from the nucleus to the cytoplasm, and plays a part in the CB chemical composition.
authors.affiliation: Sao Paulo State University - UNESP/IBILCE, Department of Biology, Rua Cristovao Colombo, 2265 - Jardim Nazareth, CEP 15054 000 Sao Jose do Rio Preto, SP, Brazil.
authors.forename: Rita Luiza
authors.initials: RL
authors.lastname: Peruquetti
authors.forename: Sebastião Roberto
authors.initials: SR
authors.lastname: Taboga
authors.forename: Lia Raquel de Souza
authors.initials: LR
authors.lastname: Santos
authors.forename: Classius de
authors.initials: Cd
authors.lastname: Oliveira
authors.forename: Maria Tercília Vilela de
authors.initials: MT
authors.lastname: Azeredo-Oliveira
mesh_terms: D000818:Animals; D001001:Anura / Q000502:physiology*; D002466:Cell Nucleolus / Q000378:metabolism*; D002467:Cell Nucleus / Q000648:ultrastructure; D002843:Chromatin / Q000378:metabolism*; D003593:Cytoplasm / Q000648:ultrastructure; D006651:Histocytochemistry; D008297:Male; D008853:Microscopy; D013091:Spermatogenesis; D013093:Spermatogonia / Q000166:cytology*
chemical_list: D002843:Chromatin