Immunofluorescence and ultrastructural analysis of the chromatoid body during spermatogenesis of Triatoma platensis and T. rubrovaria (Hemiptera, Triatominae).
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.
Laboratory of Cell Biology, Department of Biology, Institute of Biosciences, Humanities and the Exact Sciences, Sao Paulo State University-Júlio de Mesquita Filho (UNESP/IBILCE), Sao Jose do Rio Preto, SP, Brazil. Electronic address: dauto.borgueti@hotmail.com.
Adauto de Oliveira
Ade O
Borgueti
Laboratory of Cell Biology, Department of Biology, Institute of Biosciences, Humanities and the Exact Sciences, Sao Paulo State University-Júlio de Mesquita Filho (UNESP/IBILCE), Sao Jose do Rio Preto, SP, Brazil. Electronic address: kaiochaboli@hotmail.com.
Kaio Cesar Chaboli
KC
Alevi
Laboratory of Cell Biology, Department of Biology, Institute of Biosciences, Humanities and the Exact Sciences, Sao Paulo State University-Júlio de Mesquita Filho (UNESP/IBILCE), Sao Jose do Rio Preto, SP, Brazil. Electronic address: rosanass@ibilce.unesp.br.
Rosana
R
Silistino-Souza
Laboratory of Parasitology, Department of Biological Sciences, College of Pharmaceutical Sciences, Sao Paulo State University-Júlio de Mesquita Filho, (UNESP/FCFAR), Araraquara, SP, Brazil. Electronic address: rosaja@fcfar.unesp.br.
João Aristeu da
JA
Rosa
Laboratory of Cell Biology, Department of Biology, Institute of Biosciences, Humanities and the Exact Sciences, Sao Paulo State University-Júlio de Mesquita Filho (UNESP/IBILCE), Sao Jose do Rio Preto, SP, Brazil. Electronic address: tercilia@ibilce.unesp.br.
Maria Tercília Vilela de
MT
Azeredo-Oliveira
D000818:Animals; D002466:Cell Nucleolus / Q000648:ultrastructure; D002868:Chromosomal Proteins, Non-Histone / Q000737:chemistry; D003593:Cytoplasm / Q000648:ultrastructure; D005455:Fluorescent Antibody Technique; D006651:Histocytochemistry; D008297:Male; D008540:Meiosis; D046529:Microscopy, Electron, Transmission; D013087:Spermatids / Q000648:ultrastructure; D013091:Spermatogenesis; D013093:Spermatogonia / Q000648:ultrastructure; D014224:Triatoma / Q000502:physiology* / Q000648:ultrastructure*
D002868:Chromosomal Proteins, Non-Histone; C047458:fibrillarin
Nucleolar persistence; Post-meiotic transcriptional activity; Spermiogenesis