Immunofluorescence and ultrastructural analysis of the chromatoid body during spermatogenesis of Triatoma platensis and T. rubrovaria (Hemiptera, Triatominae)

Author(s)

Borgueti, Adauto de Oliveira ^[1] ; Chaboli Alevi, Kaio Cesar ^[1] ; Silistino-Souza, Rosana ^[1] ; da Rosa, Joao Aristeu ^[2] ; Vilela de Azeredo-Oliveira, Maria Tercilia ^[1]

Affiliation

^[1] Sao Paulo State Univ Julio de Mesquita Filho UNES, Dept Biol, Cell Biol Lab, Inst Biosci Humanities & Exact Sci, Sao Jose Do Rio Preto, SP - Brazil

^[2] Sao Paulo State Univ Julio de Mesquita Filho, UNESP FCFAR, Coll Pharmaceut Sci, Lab Parasitol, Dept Biol Sci, Araraquara, SP - Brazil

• Document type: Journal article
• Source: Micron; v. 74, p. 44-46, JUL 2015.
• Web of Science Citations: 3

Abstract

This study sought to analyze spermatogenesis in two species of triatomines (Triatoma rubrovaria and T. platensis) by focusing on the chromatoid body (CB) during three stages of spermatogenesis (spermatocytogenesis, meiosis, and spermiogenesis). The cytochemistry technique known as silver impregnation revealed nucleolar persistence. We suggest that this phenomenon is fundamental to the formation of the CB during spermatogenesis, as it allows for the nucleolus or nucleolar fragments to maintain their transcriptional activity during the entire meiosis phase and to apply all transcribed RNA to CB formation. The ultrastructural analysis of T. platensis and T. rubrovaria spermatids revealed the presence of the nucleolus within the spermatid nucleus, as well as the CB near the nuclear membrane. Immunofluorescence for fibrillarin revealed the presence of protein in both the nucleolus and the cytoplasm of spermatogonia. Based on these findings, we suggest that the formation of the CB begins during the first phase of spermatogenesis, or spermatocytogenesis. Furthermore, we also observed the presence of fibrillarin protein in the CB near the elongating spermatids. Unlike the spermatogonia, spermatids showed no fibrillarin markings in the nucleolar region, a finding which is consistent with the lack of post-meiotic transcriptional activity during triatomine spermiogenesis. Thus, this study suggests that the formation of the CB begins during spermatocytogenesis and is intensified by transcriptional activity when nucleolar persistence occurs in meiosis. Moreover, the findings are consistent with the absence of transcriptional activity in the nucleolus during spermiogenesis, and they demonstrate that all transcriptional activity during spermatid differentiation is supported by the CB. (C) 2015 Elsevier Ltd. All rights reserved. (AU)

• FAPESP's process: 13/19764-0 - Cytotaxonomy and chromosomal evolution in Triatominae subfamily
• Grantee: Kaio Cesar Chaboli Alevi
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 10/01193-9 - Morphological and ultrastructural spermatogenesis study, emphasizing the nucleolar cycle and the chromatoid body formation in triatomines (Triatominae, Heteroptera), Chagas disease vectors.
• Grantee: Maria Tercília Vilela de Azeredo Oliveira
• Support Opportunities: Regular Research Grants