Apoptosis-associated signaling pathways are required for chemotherapy-mediated female germ cell destruction

(1) In Smerinthus populi, Pieris brassicæ, and a number of other species of moths and butterflies the cytoplasmic bodies have been followed out. (2) The micromitosome lias been followed from the spermatocyte back into the secondary spermatogonium. It is very probably present in the primordial germ-cell. (3) The micromitosome has been definitely found in the female. (4) The micromitosome seems to divide in all divisions, and I consider that it is a constant factor in the spermatids of Smerinthus. (5) The probable nature and function of the micromitosome is discussed. (6) The mitochondria have been carefully examined in the male and female germ-cell in all stages except in the maturation division of the female and in fertilisation. (7) It has been shown that in early stages the cytoplasmic bodies of the female resemble those of the male. (8) There is a definite period, judged to be about the beginning of growth stage, when the subsequent fate of the mitochondria in the male becomes different from that of the female. (9) The remarkable formation of chromophobe and chromophile zones in the male mitochondrial body aud the use of these zones are described. (10) The formation of the macromitosome from the mitochondria is described. (11) The changes undergone by the macromitosome in sperm formation are followed out. (12) The presence of the acroblasts in the fairly early growth period of the spermatocyte is described. (13) The complicated evolutions of these bodies in division of the cells, their subsequent fate and' their probable nature are discussed. (14) The staining and fixing reactions of the cytoplasmic bodies are fully described. (15) A number of abnormalities have been described. (16) The centrosome has been shown to divide in the young spermatid, and one centrosome is probably lost, but definite evidence is not forthcoming.

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Ligand–Receptor Interactions Elucidate Sex-Specific Pathways in the Trajectory From Primordial Germ Cells to Gonia During Human Development

Frontiers in Cell and Developmental Biology ◽

10.3389/fcell.2021.661243 ◽

2021 ◽

Vol 9 ◽

Author(s):

Arend W. Overeem ◽

Yolanda W. Chang ◽

Jeroen Spruit ◽

Celine M. Roelse ◽

Susana M. Chuva De Sousa Lopes

Keyword(s):

Germ Cell ◽

Signaling Pathways ◽

Germ Cells ◽

Tyrosine Kinases ◽

Intracellular Localization ◽

Primordial Germ Cells ◽

Cell Lineage ◽

Systematic Analysis ◽

Receptor Interactions

The human germ cell lineage originates from primordial germ cells (PGCs), which are specified at approximately the third week of development. Our understanding of the signaling pathways that control this event has significantly increased in recent years and that has enabled the generation of PGC-like cells (PGCLCs) from pluripotent stem cells in vitro. However, the signaling pathways that drive the transition of PGCs into gonia (prospermatogonia in males or premeiotic oogonia in females) remain unclear, and we are presently unable to mimic this step in vitro in the absence of gonadal tissue. Therefore, we have analyzed single-cell transcriptomics data of human fetal gonads to map the molecular interactions during the sex-specific transition from PGCs to gonia. The CellPhoneDB algorithm was used to identify significant ligand–receptor interactions between germ cells and their sex-specific neighboring gonadal somatic cells, focusing on four major signaling pathways WNT, NOTCH, TGFβ/BMP, and receptor tyrosine kinases (RTK). Subsequently, the expression and intracellular localization of key effectors for these pathways were validated in human fetal gonads by immunostaining. This approach provided a systematic analysis of the signaling environment in developing human gonads and revealed sex-specific signaling pathways during human premeiotic germ cell development. This work serves as a foundation to understand the transition from PGCs to premeiotic oogonia or prospermatogonia and identifies sex-specific signaling pathways that are of interest in the step-by-step reconstitution of human gametogenesis in vitro.

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Notch pathway regulates female germ cell meiosis progression and early oogenesis events in fetal mouse

Cell Cycle ◽

10.4161/cc.27708 ◽

2014 ◽

Vol 13 (5) ◽

pp. 782-791 ◽

Cited By ~ 32

Author(s):

Yan-Min Feng ◽

Gui-Jin Liang ◽

Bo Pan ◽

XunSi Qin ◽

Xi-Feng Zhang ◽

...

Keyword(s):

Germ Cell ◽

Notch Pathway ◽

Fetal Mouse ◽

Female Germ Cell

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Society for Reproductive Biology Founders' Lecture 2007. Insights into germ cell biology: from the bench to the clinic

Reproduction Fertility and Development ◽

10.1071/rd07090 ◽

2007 ◽

Vol 19 (7) ◽

pp. 783 ◽

Cited By ~ 1

Author(s):

Angshumoy Roy ◽

Martin M. Matzuk

Keyword(s):

Germ Cell ◽

Cell Biology ◽

Transforming Growth Factor ◽

Transforming Growth Factor Β ◽

Signalling Pathways ◽

Male And Female ◽

Paracrine Signalling ◽

Fertility Clinic ◽

Female Germ Cell

The germline is unique among tissues in being the only lineage that is transmitted through generations. The gonadal somatic cells that interact with male and female germ cells are equally important for their juxtacrine and paracrine signalling pathways that lead to the formation of functionally mature gametes and healthy progeny. The present review summarises exciting new studies that our group and others have achieved at the frontier of male and female germ cell biology and in studying transforming growth factor-β signalling pathways in oocyte–somatic cell interactions and gonadal growth and differentiation. In the process, we have produced over 70 transgenic and knockout models to study reproduction in vivo. These models have helped us identify novel and unexplored areas of germ cell biology and translate this work into the fertility clinic.

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Structure of the germarium and female germ-cell clusters in Thulinius ruffoi (Bertolani, 1982) (Tardigrada: Eutardigrada: Parachela)

Zoological Journal of the Linnean Society ◽

10.1093/zoolinnean/zlz108 ◽

2019 ◽

Author(s):

Kamil Janelt ◽

Marta Jezierska ◽

Sebastian Student ◽

Izabela Poprawa

Keyword(s):

Germ Cell ◽

Laser Scanning ◽

Spatial Organization ◽

Germ Line ◽

Anterior Part ◽

Confocal Laser ◽

Freshwater Species ◽

Cell Clusters ◽

Scanning Transmission ◽

Female Germ Cell

Abstract Thulinius ruffoi is a freshwater species that has the ability to reproduce via parthenogenesis. A meroistic polytrophic ovary is present in this species. Analyses of the germarium structure, and formation and organization of female germ-cell clusters were performed using light, confocal laser scanning, transmission electron and serial block-face scanning electron microscopy. The germarium is the small, anterior part of an ovary that contains putative germ-line stem cells. In the studied species, the female germ-cell clusters are large and branched. Only one cell in each cluster develops into an oocyte, while all the other cells become trophocytes. In this paper, we present the ﬁrst report on the presence of F-actin as a component of the intercellular bridges that connect the cells in the germ-cell cluster of T. ruffoi. Moreover, our results show that the female germ-cell clusters are formed as the result of both synchronous and asynchronous divisions and that their organization can vary not only between individuals of the investigated species, but also that clusters developing simultaneously within the same ovary can have a different spatial organization.

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