Differentiation of primordial germ cells in the embryonic development of Thermobia domestica, Pack. (Thysanura): an ultrastructural study

Development ◽  
1977 ◽  
Vol 38 (1) ◽  
pp. 93-114
Author(s):  
Jerzy Klag
Keyword(s):  
Embryonic Development ◽  
Germ Cells ◽  
Morphological Changes ◽  
Sex Differentiation ◽  
Primordial Germ Cells ◽  
Postembryonic Development ◽  
Thermobia Domestica ◽  
Dense Bodies ◽  
Accessory Nuclei ◽  
High Degree

The primordial germ cells (PGCs) of Thermobia domestica undergo some morphological changes during the embryonic development. Most conspicuous are the changes in the ultrastructure of the nucleus, whose envelope shows a high degree of activity. Two types of vesicles bleb off from the nucleus; the ones with the light interior are called the accessory nuclei, the others, with electron-opaque contents, have been termed the dense bodies. The nucleolus, initially clustered at the nucleus centre, undergoes dispersion and assembles again towards the end of embryonic development. At the same time, the sex differentiation of PGCs takes place. It is preceded by an increase in the activity of Golgi complexes and in the volume of lysosomes and lamellar bodies, the latter giving rise to lipid droplets. At the early stages of postembryonic development, preoogonia and prespermatogonia can readily be distinguished. Preoogonia have a wavy-surfaced nucleus and their cytoplasm contains dense bodies. In prespermatogonia, the nucleus is spherical with smooth envelope and there are no dense bodies in the cytoplasm. Throughout the period studied there occur nucleolus-like bodies and nuage material considered to be the germ-cell determinants in this species.

scholarly journals Comparison of the Transcriptomic and Epigenetic Profiles of Gonadal Primordial Germ Cells of White Leghorn and Green-Legged Partridgelike Chicken Embryos

Genes ◽  
2021 ◽  
Vol 12 (7) ◽  
pp. 1090
Author(s):  
Aleksandra Dunislawska ◽  
Maria Siwek ◽  
Katarzyna Stadnicka ◽  
Marek Bednarczyk
Keyword(s):  
Embryonic Development ◽  
Germ Cells ◽  
Developmental Stages ◽  
Primordial Germ Cells ◽  
Genetic Material ◽  
Reproductive Traits ◽  
Germline Stem Cells ◽  
White Leghorn ◽  
Methylation Analysis ◽  
Global Methylation

The Green-legged Partridgelike fowl is a native, dual-purpose Polish chicken. The White Leghorn has been intensively selected for several decades to mainly improve reproductive traits. Primordial germ cells (PGCs) represent the germline stem cells in chickens and are the only cells that can transfer the information stored in the genetic material from generation to generation. The aim of the study was to carry out a transcriptomic and an epigenetic comparison of the White Leghorn and Green-legged Partridgelike gonadal PGCs (gPGCs) at three developmental stages: days 4.5, 8, and 12 of the embryonic development. RNA and DNA were isolated from collected gPGCs. The RNA was further subjected to microarray analysis. An epigenetic analysis was performed based on the global methylation analysis and qMSP method for the particular silenced genes demonstrated in transcriptomic analysis. Statistically significant differences between the gPGCs from both breeds were detected on the day 8 of embryonic development. Global methylation analysis showed significant changes at the methylation level in the White Leghorn gPGCs on day 8 of embryonic development. The results suggest faster development of Green-legged Partridgelike embryos as compared to White Leghorn embryos. Changes in the levels of gene expression during embryonic development are determined by genetic and environmental factors, and this variability is influenced by breed and gender.

Sex differentiation of germ cells in the teleost, Oryzias latipes, during normal embryonic development

Development ◽  
1972 ◽  
Vol 28 (2) ◽  
pp. 385-395
Author(s):  
Noriyuki Satoh ◽  
Nobuo Egami
Keyword(s):  
Germ Cells ◽  
Meiotic Prophase ◽  
Sex Differentiation ◽  
Primordial Germ Cells ◽  
Oryzias Latipes ◽  
The Other ◽  
Histological Structure ◽  
The Mean ◽  
Further Development ◽  
Normal Embryonic Development

Mitotic and meiotic activities of germ cells during early development in the medaka, Oryzias latipes, are dealt with in this report. Primordial germ cells were obviously distinguishable from somatic cells 3 days after fertilization and began to proliferate about 7 days after fertilization. The mean number of primordial germ cells increased during a period of 7–10 days after fertilization, reaching about 90 immediately before hatching. Newly hatched fry could be classified into two types according to the number and the nucleic activity of germ cells in the gonadal rudiment. One type consisted of fry containing about 100 germ cells and no cells in the meiotic prophase. In the other type of fry the number of germ cells increased by mitotic divisions and some of the cells began to enter into the meiotic prophase. During the course of further development the fry of the former type differentiated into males and the latter into females. Therefore it can be concluded that the morphological sex differentiation of germ cells occurs at the time of hatching. However, no sexual differences in the histological structure of somatic elements in the gonad are observable at that time.

Function of TGF-?2 in the growth of chicken primordial germ cells and germinal ridge stroma cells during embryonic development

2004 ◽  
Vol 301A (4) ◽  
pp. 290-296 ◽  
Author(s):  
Tsuyoshi Fujioka ◽  
Tomoki Soh ◽  
Noboru Fujihara ◽  
Masa-Aki Hattori
Keyword(s):  
Embryonic Development ◽  
Germ Cells ◽  
Primordial Germ Cells

scholarly journals NUP50 is necessary for the survival of primordial germ cells in mouse embryos

Reproduction ◽  
2016 ◽  
Vol 151 (1) ◽  
pp. 51-58 ◽  
Author(s):  
Eunsook Park ◽  
Bobae Lee ◽  
Bruce E Clurman ◽  
Keesook Lee
Keyword(s):  
Embryonic Development ◽  
Germ Cells ◽  
Nuclear Pore Complex ◽  
Essential Role ◽  
Primordial Germ Cells ◽  
Mouse Embryos ◽  
Nuclear Pore ◽  
Progressive Loss ◽  
And Function ◽  
Deficient Mice

Nucleoporin 50 kDa (NUP50), a component of the nuclear pore complex, is highly expressed in male germ cells, but its role in germ cells is largely unknown. In this study, we analyzed the expression and function of NUP50 during the embryonic development of germ cells using NUP50-deficient mice. NUP50 was expressed in germ cells of both sexes at embryonic day 15.5 (E15.5), E13.5, and E12.5. In addition, NUP50 expression was also detected in primordial germ cells (PGCs) migrating into the genital ridges at E9.5. The gonads of Nup50−/− embryos of both sexes contained few PGCs at both E11.5 and E12.5 and no developing germ cells at E15.5. The migratory PGCs in Nup50−/− embryos at E9.5 showed increased apoptosis but a normal rate of proliferation, resulting in the progressive loss of germ cells at later stages. Taken together, these results suggest that NUP50 plays an essential role in the survival of PGCs during embryonic development.

scholarly journals Determination of production capacity of circulated primordial germ cells (circulated-PGCs) of KUB chicken using lysis buffer ammonium chloride potassium (ACK)

2016 ◽  
Vol 21 (1) ◽  
pp. 55
Author(s):  
Soni Sopiyana ◽  
Iman Supriatna ◽  
M. Agus Setiadi ◽  
Mohamad Fahrudin
Keyword(s):  
Embryonic Development ◽  
Ammonium Chloride ◽  
Germ Cells ◽  
Primordial Germ Cells ◽  
Production Capacity ◽  
Development Stage ◽  
Simple Method ◽  
Average Production ◽  
Short Period ◽  
Lysis Buffer

<p class="abstrak2">In poultry embryos, primordial germ cells (PGCs) are progenitor cells for gametes, which have unique migration pathway. Primordial germ cells arise from epiblast in germinal crescent and circulate through the bloodstream for a short period of time, then leave blood vessel to migrate toward gonads. The aim of this study was to determine the potential production capacity of circulated-PGCs of KUB chicken at different developmental stages of embryo using a rapid and simple method. Seventy five KUB chicken fertile eggs were divided into five groups and incubated at 38.5 <sup>0</sup>C with a humidity of 60%. Hatching was set to the embryonic development stage of 14-18. The blood was collected through dorsal aorta using micropipette under microscope. The collected blood was placed in a 1.5 ml eppendorf tube which was previously filled with 100 µl phosphate buffered saline without Ca<sup>2+</sup> and Mg<sup>2+</sup> (PBS-) mixed with fetal bovine serum (FBS) with a ratio of 90%:10%. The PGCs were purified using lysis buffer ammonium chloride potassium method. The results showed that average production of circulated-PGCs per embryo of KUB chicken were significantly affected by stage of embryonic development (P &lt;0.05). The average production of circulated-PGCs at stage 14, 15, 16, 17, and 18 were 37.9; 53.5; 49.8; 38.3; and 33.5 respectively. The number of circulated-PGCs was not different among stages 14, 17 nor 18. The highest number of circulated-PGCs of KUB chicken was obtained at stage 15, so that the isolation and collection of PGCs through the blood circulation was recommended in stage 15.</p><strong>Key Words: </strong>KUB Chicken, PGCs, Embryonic Development Stage, Ammonium Chloride Potassium

scholarly journals XY oocytes of sex-reversed females with a Sry mutation deviate from the normal developmental process beyond the mitotic stage†

2018 ◽  
Vol 100 (3) ◽  
pp. 697-710 ◽  
Author(s):  
Akihiko Sakashita ◽  
Takuya Wakai ◽  
Yukiko Kawabata ◽  
Chiaki Nishimura ◽  
Yusuke Sotomaru ◽  
...  
Keyword(s):  
Germ Cells ◽  
Developmental Process ◽  
Sex Differentiation ◽  
Primordial Germ Cells ◽  
Primordial Follicle ◽  
Genetic Ablation ◽  
Female Mice ◽  
Meiotic Progression ◽  
Molecular Etiology ◽  
Mitotic Proliferation

Abstract The fertility of sex-reversed XY female mice is severely impaired by a massive loss of oocytes and failure of meiotic progression. This phenomenon remains an outstanding mystery. We sought to determine the molecular etiology of XY oocyte dysfunction by generating sex-reversed females that bear genetic ablation of Sry, a vital sex determination gene, on an inbred C57BL/6 background. These mutant mice, termed XYsry− mutants, showed severe attrition of germ cells during fetal development, resulting in the depletion of ovarian germ cells prior to sexual maturation. Comprehensive transcriptome analyses of primordial germ cells (PGCs) and postnatal oocytes demonstrated that XYsry− females had deviated significantly from normal developmental processes during the stages of mitotic proliferation. The impaired proliferation of XYsry− PGCs was associated with aberrant β-catenin signaling and the excessive expression of transposable elements. Upon entry to the meiotic stage, XYsry− oocytes demonstrated extensive defects, including the impairment of crossover formation, the failure of primordial follicle maintenance, and no capacity for embryo development. Together, these results suggest potential molecular causes for germ cell disruption in sex-reversed female mice, thereby providing insights into disorders of sex differentiation in humans, such as “Swyer syndrome,” in which patients with an XY karyotype present as typical females and are infertile.

SEX DIFFERENTIATION IN THE PACIFIC SALMON ONCORHYNCHUS KETA (WALBAUM)

1953 ◽  
Vol 31 (2) ◽  
pp. 73-79 ◽  
Author(s):  
J. G. Robertson
Keyword(s):  
Germ Cells ◽  
Chum Salmon ◽  
Pacific Salmon ◽  
Sex Differentiation ◽  
Primordial Germ Cells ◽  
The Other ◽  
Oncorhynchus Keta ◽  
Progressive Development ◽  
The Pacific ◽  
Female Phase

The differentiation of the gonad is described in chum salmon embryos and alevins. Contrary to classical findings in teleosts, sex differentiation in the chum salmon proceeds in the male or female direction without an intermediate female phase. From an initially indifferent gonad there is a progressive development of one sex or the other. The organ forms as a fold from the splanchnic mesoderm and, at the time of first appearance, contains primordial germ cells. These enlarge to form the definitive germ cells which, after a series of divisions, form smaller oogonia or spermatogonia. Oogonia are followed by primary and secondary (growing) oocytes, the appearance of which is the criterion of sex distinction. Spermatogonia continue to multiply but do not undergo growth in the alevin. The ovary develops an open endovarial canal and is supported by a prominent mesovarium. The testis remains small and, in the alevin, develops no ducts. It is suspended by a mesorchium.

Gnrh3 Regulates PGC Proliferation and Sex Differentiation in Developing Zebrafish

Endocrinology ◽  
2019 ◽  
Vol 161 (1) ◽  
Author(s):  
Ke Feng ◽  
Xuefan Cui ◽  
Yanlong Song ◽  
Binbin Tao ◽  
Ji Chen ◽  
...  
Keyword(s):  
Germ Cells ◽  
Sex Differentiation ◽  
Primordial Germ Cells ◽  
Mek Inhibitor ◽  
Gonadotropin Releasing Hormone ◽  
Terminal Deoxynucleotidyl Transferase ◽  
Hormone Release ◽  
Wild Type ◽  
Gnrh Analog ◽  
Biased Sex Ratio

Abstract Gonadotropin-releasing hormone (Gnrh) plays important roles in reproduction by stimulating luteinizing hormone release, and subsequently ovulation and sperm release, ultimately controlling reproduction in many species. Here we report on a new role for this decapeptide. Surprisingly, Gnrh3-null zebrafish generated by CRISPR/Cas9 exhibited a male-biased sex ratio. After the dome stage, the number of primordial germ cells (PGCs) in gnrh3-/- fish was lower than that in wild-type, an effect that was partially rescued by gnrh3 overexpression. A terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) analysis revealed no detectable apoptosis of PGCs in gnrh3-/- embryos. Proliferating PGCs could be detected in wild-type embryos, while there was no detectable signal in gnrh3-/- embryos. Compared with wild type, the phosphorylation of AKT was not significantly different in gnrh3-/- embryos, but the phosphorylation of ERK1/2 decreased significantly. Treatment with a Gnrh analog (Alarelin) induced ERK1/2 phosphorylation and increased PGC numbers in both wild-type and gnrh3-/- embryos, and this was blocked by the MEK inhibitor PD0325901. The relative expression of sox9a, amh, and cyp11b were significantly upregulated, while cyp19a1a was significantly downregulated at 18 days post-fertilization in gnrh3-/- zebrafish. Taken together, these results indicate that Gnrh3 plays an important role in early sex differentiation by regulating the proliferation of PGCs through a MAPK-dependent path.

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