The onset and evolution of the meiotic prophase were assessed by histological and cytological techniques in fetal and neonatal ovaries obtained from day 13 postcoitum to day 11 postpartum in the golden hamster (Mesocricetus auratus). The histological technique based on the Feulgen stain and the cytological technique based on the Giemsa stain of isolated nuclei were judged to be specific for staining chromatin and chromosomal DNA. The results obtained with both techniques were quite similar and confirmed most of the meiotic prophase takes place during the neonatal period. However, at variance with other reports, it was found that the meiotic prophase starts on day 14 postcoitum. This discrepancy is attributed to the greater specificity of techniques and time span covered in the present study.
Download full-text PDF |
Source |
|---|---|
| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1233326 | PMC |
Publication Analysis
Top Keywords
Similar Publications
Centromere positioning orchestrates telomere bouquet formation and the initiation of meiotic differentiation.
Nat Commun
January 2025
Instituto de Biología Funcional y Genómica, Zacarías González 2, Salamanca, 37007, Spain.
Accurate gametogenesis requires the establishment of the telomere bouquet, an evolutionarily conserved, 3D chromosomal arrangement. In this spatial configuration, telomeres temporarily aggregate at the nuclear envelope during meiotic prophase, which facilitates chromosome pairing and recombination. The mechanisms governing the assembly of the telomere bouquet remain largely unexplored, primarily due to the challenges in visualizing and manipulating the bouquet.
View Article and Find Full Text PDFTranscriptional Integration of Meiotic Prophase I Progression and Early Oocyte Differentiation.
bioRxiv
January 2025
MCB Graduate Program, Cell Biology, and Biochemistry, Brown University, 70 Ship St., Box G-E4, Providence, RI 02903, USA.
Female reproductive senescence results from the regulated depletion of a finite pool of oocytes called the ovarian reserve. This pool of oocytes is initially established during fetal development, but the oocytes that comprise it must remain quiescent for decades until they are activated during maturation in adulthood. In order for developmentally competent oocytes to populate the ovarian reserve they must successfully initiate both meiosis and oogenesis.
View Article and Find Full Text PDFDiversification and recurrent adaptation of the synaptonemal complex in Drosophila.
PLoS Genet
January 2025
Department of Zoology, University of British Columbia, Vancouver, British Columbia, Canada.
The synaptonemal complex (SC) is a protein-rich structure essential for meiotic recombination and faithful chromosome segregation. Acting like a zipper to paired homologous chromosomes during early prophase I, the complex is a symmetrical structure where central elements are connected on two sides by the transverse filaments to the chromatin-anchoring lateral elements. Despite being found in most major eukaryotic taxa implying a deeply conserved evolutionary origin, several components of the complex exhibit unusually high rates of sequence turnover.
View Article and Find Full Text PDFArgonaute proteins are best known for their role in microRNA-mediated post-transcriptional gene silencing. Here, we show that AGO3 and AGO4, but not AGO2, localize to the sex chromatin of pachytene spermatocytes where they are required for transcriptional silencing of XY-linked genes, known as Meiotic Sex Chromosome Inactivation (MSCI). Using an mouse, we show that AGO3 and AGO4 are key regulators of spermatogenesis, orchestrating expression of meiosis-related genes during prophase I while maintaining silencing of spermiogenesis genes.
View Article and Find Full Text PDFGonadal sex and temperature independently influence germ cell differentiation and meiotic progression in .
Proc Natl Acad Sci U S A
January 2025
Department of Cell Biology, Duke University Medical Center, Durham, NC 27701.
In species with genetic sex determination (GSD), the sex identity of the soma determines germ cell fate. For example, in mice, XY germ cells that enter an ovary differentiate as oogonia, whereas XX germ cells that enter a testis initiate differentiation as spermatogonia. However, numerous species lack a GSD system and instead display temperature-dependent sex determination (TSD).
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!