Identification of a candidate c-mos repressor that restricts transcription of germ cell-specific genes.

The c-mos proto-oncogene is specifically expressed in female and male germ cells. Previous studies identified a negative regulatory element (NRE) upstream of the c-mos promoter that suppresses c-mos transcription in transfected NIH 3T3 cells. In this study, we used gel shift assays to detect proteins in nuclear extracts of NIH 3T3 cells that bind to the c-mos NRE in a sequence-specific manner. One protein was found to bind to a region of the NRE which was shown by site-directed mutagenesis to be required for suppression of c-mos transcription. This factor was present in nuclear extracts of several somatic cell lines and tissues but not in male germ cells in which c-mos is transcribed, suggesting that it is a somatic cell repressor of c-mos transcription. The binding site of the candidate repressor within the c-mos NRE consists of sequences related to putative NREs identified in two other male germ cell-specific genes (encoding protamine 2 and phosphoglycerate kinase 2). The c-mos repressor bound and could be UV cross-linked to these protamine 2 and phosphoglycerate kinase 2 gene sequences as a protein with an apparent molecular mass of approximately 30 kDa. The repressor binding site is also conserved in two other germ cell-specific genes (encoding testis-specific cytochrome c and heat shock-like protein 70), suggesting that the c-mos repressor may be generally involved in suppressing transcription of germ cell-specific genes in somatic cells.

Download Full-text

Genetic control of programmed cell death in the Caenorhabditis elegans hermaphrodite germline

Development ◽

10.1242/dev.126.5.1011 ◽

1999 ◽

Vol 126 (5) ◽

pp. 1011-1022 ◽

Cited By ~ 8

Author(s):

T.L. Gumienny ◽

E. Lambie ◽

E. Hartwieg ◽

H.R. Horvitz ◽

M.O. Hengartner

Keyword(s):

Cell Death ◽

Caenorhabditis Elegans ◽

Germ Cell ◽

Somatic Cell ◽

Cell Fate ◽

Germ Cells ◽

Mapk Pathway ◽

Apoptotic Cell ◽

C Elegans ◽

Pathway Activation

Development of the nematode Caenorhabditis elegans is highly reproducible and the fate of every somatic cell has been reported. We describe here a previously uncharacterized cell fate in C. elegans: we show that germ cells, which in hermaphrodites can differentiate into sperm and oocytes, also undergo apoptotic cell death. In adult hermaphrodites, over 300 germ cells die, using the same apoptotic execution machinery (ced-3, ced-4 and ced-9) as the previously described 131 somatic cell deaths. However, this machinery is activated by a distinct pathway, as loss of egl-1 function, which inhibits somatic cell death, does not affect germ cell apoptosis. Germ cell death requires ras/MAPK pathway activation and is used to maintain germline homeostasis. We suggest that apoptosis eliminates excess germ cells that acted as nurse cells to provide cytoplasmic components to maturing oocytes.

Download Full-text

Abnormal Meiosis Initiation in Germ Cell Caused by Aberrant Differentiation of Gonad Somatic Cell

Oxidative Medicine and Cellular Longevity ◽

10.1155/2019/8030697 ◽

2019 ◽

Vol 2019 ◽

pp. 1-8

Author(s):

Min Chen ◽

Suren Chen ◽

Jingjing Zhou ◽

Fangfang Dong ◽

...

Keyword(s):

Cell Differentiation ◽

Germ Cell ◽

Somatic Cell ◽

Germ Cells ◽

Somatic Cells ◽

Ectopic Expression ◽

Genital Ridge ◽

Male And Female ◽

Germ Cell Differentiation ◽

Exact Function

The interaction between germ cell and somatic cell plays important roles in germ cell development. However, the exact function of gonad somatic cell in germ cell differentiation is unclear. In the present study, the function of gonad somatic cell in germ cell meiosis was examined by using mouse models with aberrant somatic cell differentiation. In Wt1R394W/R394W mice, the genital ridge is absent due to the apoptosis of coelomic epithelial cells. Interestingly, in both male and female Wt1R394W/R394W germ cells, STRA8 was detected at E12.5 and the scattered SYCP3 foci were observed at E13.5 which was consistent with control females. In Wt1-/flox; Cre-ERTM mice, Wt1 was inactivated by the injection of tamoxifen at E9.5 and the differentiation of Sertoli and granulosa cells was completely blocked. We found that most germ cells were located outside of genital ridge after Wt1 inactivation. STRA8, SYCP3, and γH2AX proteins were detected in germ cells of both male and female Wt1-/flox; Cre-ERTM gonads, whereas no thread-like SYCP3 signal was observed. Our study demonstrates that aberrant development of gonad somatic cells leads to ectopic expression of meiosis-associated genes in germ cells, but meiosis was arrested before prophase I. These results suggest that the proper differentiation of gonad somatic cells is essential for germ cell meiosis.

Download Full-text

Overexpression of peroxisomal testis-specific 1 protein induces germ cell apoptosis and leads to infertility in male mice

Molecular Biology of the Cell ◽

10.1091/mbc.e09-12-0993 ◽

2011 ◽

Vol 22 (10) ◽

pp. 1766-1779 ◽

Cited By ~ 16

Author(s):

Karina Kaczmarek ◽

Maja Studencka ◽

Andreas Meinhardt ◽

Krzysztof Wieczerzak ◽

Sven Thoms ◽

...

Keyword(s):

Cell Death ◽

Germ Cell ◽

Germ Cells ◽

Specific Gene ◽

Male Mice ◽

Terminal Part ◽

Male Germ Cells ◽

Germ Cell Apoptosis ◽

Induced Apoptosis

Peroxisomal testis-specific 1 gene (Pxt1) is the only male germ cell–specific gene that encodes a peroxisomal protein known to date. To elucidate the role of Pxt1 in spermatogenesis, we generated transgenic mice expressing a c-MYC-PXT1 fusion protein under the control of the PGK2 promoter. Overexpression of Pxt1 resulted in induction of male germ cells’ apoptosis mainly in primary spermatocytes, finally leading to male infertility. This prompted us to analyze the proapoptotic character of mouse PXT1, which harbors a BH3-like domain in the N-terminal part. In different cell lines, the overexpression of PXT1 also resulted in a dramatic increase of apoptosis, whereas the deletion of the BH3-like domain significantly reduced cell death events, thereby confirming that the domain is functional and essential for the proapoptotic activity of PXT1. Moreover, we demonstrated that PXT1 interacts with apoptosis regulator BAT3, which, if overexpressed, can protect cells from the PXT1-induced apoptosis. The PXT1-BAT3 association leads to PXT1 relocation from the cytoplasm to the nucleus. In summary, we demonstrated that PXT1 induces apoptosis via the BH3-like domain and that this process is inhibited by BAT3.

Download Full-text

217 PROTEIN-INDUCED TRANSDIFFERENTIATION INTO MALE GERM CELL-LIKE LINEAGE FROM CHICKEN FETAL BONE MARROW STEM CELLS

Reproduction Fertility and Development ◽

10.1071/rdv24n1ab217 ◽

2012 ◽

Vol 24 (1) ◽

pp. 220

Author(s):

J. M. Yoo ◽

J. J. Park ◽

K. Gobianand ◽

J. Y. Ji ◽

J. S. Kim ◽

...

Keyword(s):

Stem Cells ◽

Bone Marrow ◽

Retinoic Acid ◽

Germ Cell ◽

Germ Cells ◽

Cultured Cells ◽

Male Germ Cell ◽

Male Germ Cells ◽

Germ Cell Differentiation ◽

Transgenic Chickens

Bone marrow (BM)-derived stem cells are capable of transdifferentiation into multilineage cells like muscle, bone, cartilage, fat and nerve cells. In this study, we investigated the capability of mesenchymal stem cells (MSC) derived from BM into germ cell differentiation in the chicken. Chicken MSCs were isolated from BM of day 20 fertilized fetal chicken with Ficoll-Paque Plus. Isolated cells were cultured in advance-DMEM (ADMEM) supplemented with 10% fetal bovine serum and antibiotics. Once confluent, cells were subcultured until five passages. The cultured cells showed fibroblast-like morphology. The cells had positive expressions of Oct4, Sox2 and Nanog. Two induction methods were conducted to examine the ability of transdifferentation into male germ cells. In group 1, MSC were cultured in ADMEM containing retinoic acid and chicken testicular extracts proteins for 10 to 15 days. In group 2, MSC were permeabilized by streptolysin O and treated with chicken testicular protein extracts. In both treatment groups, MSC were cultured in ADMEM containing retinoic acid for 10 to 15 days. We found that chicken MSC had a positive expression of pluripotent proteins such as Oct4, Sox2, Nanog and a small population of chicken MSC seem to transdifferentiate into male germ cell-like cells. These cells expressed early germ cell markers and male germ-cell-specific markers (Dazl, C-kit, Stra8 and DDX4) as analysed by reverse transcription-PCR and immunohistochemistry. These results demonstrated that chicken MSC may differentiate into male germ cells and the same might be used as a potential source of cells for production of transgenic chickens. This study was carried out with the support of Agenda Program (Project No. PJ0064692011), RDA and Republic of Korea.

Download Full-text

Cannabinoid Receptors Signaling in the Development, Epigenetics, and Tumours of Male Germ Cells

International Journal of Molecular Sciences ◽

10.3390/ijms21010025 ◽

2019 ◽

Vol 21 (1) ◽

pp. 25 ◽

Cited By ~ 6

Author(s):

Marco Barchi ◽

Elisa Innocenzi ◽

Teresa Giannattasio ◽

Susanna Dolci ◽

Pellegrino Rossi ◽

...

Keyword(s):

Germ Cell ◽

Germ Cells ◽

Cannabinoid Receptors ◽

Endocannabinoid System ◽

Male Reproduction ◽

Metabolizing Enzymes ◽

Male Germ Cells ◽

Testicular Tumours ◽

Germ Cell Differentiation ◽

Degradative Enzymes

Endocannabinoids are natural lipid molecules whose levels are regulated by specific biosynthetic and degradative enzymes. They bind to and activate two main cannabinoid receptors type 1 (CB1) and type 2 (CB2), and together with their metabolizing enzymes form the “endocannabinoid system” (ECS). In the last years, the relevance of endocannabinoids (eCBs) as critical modulators in various aspects of male reproduction has been pointed out. Mammalian male germ cells, from mitotic to haploid stage, have a complete ECS which is modulated during spermatogenesis. Compelling evidence indicate that in the testis an appropriate “eCBs tone”, associated to a balanced CB receptors signaling, is critical for spermatogenesis and for the formation of mature and fertilizing spermatozoa. Any alteration of this system negatively affects male reproduction, from germ cell differentiation to sperm functions, and might have also an impact on testicular tumours. Indeed, most of testicular tumours develop during early germ-cell development in which a maturation arrest is thought to be the first key event leading to malignant transformation. Considering the ever-growing number and complexity of the data on ECS, this review focuses on the role of cannabinoid receptors CB1 and CB2 signaling in male germ cells development from gonocyte up to mature spermatozoa and in the induction of epigenetic alterations in these cells which might be transmitted to the progeny. Furthermore, we present new evidence on their relevance in testicular cancer.

Download Full-text

Proteomic and metabolomic analyses uncover sex-specific regulatory pathways in mouse fetal germline differentiation†

Biology of Reproduction ◽

10.1093/biolre/ioaa115 ◽

2020 ◽

Vol 103 (4) ◽

pp. 717-735

Author(s):

Yohei Hayashi ◽

Masaru Mori ◽

Kaori Igarashi ◽

Keiko Tanaka ◽

Asuka Takehara ◽

...

Keyword(s):

Oxidative Phosphorylation ◽

Germ Cell ◽

Germ Cells ◽

Cell Development ◽

Nucleotide Synthesis ◽

Male Germ Cells ◽

Regulatory Pathways ◽

Germ Cell Development ◽

Germ Cell Differentiation ◽

Germline Differentiation

Abstract Regulatory mechanisms of germline differentiation have generally been explained via the function of signaling pathways, transcription factors, and epigenetic regulation; however, little is known regarding proteomic and metabolomic regulation and their contribution to germ cell development. Here, we conducted integrated proteomic and metabolomic analyses of fetal germ cells in mice on embryonic day (E)13.5 and E18.5 and demonstrate sex- and developmental stage-dependent changes in these processes. In male germ cells, RNA processing, translation, oxidative phosphorylation, and nucleotide synthesis are dominant in E13.5 and then decline until E18.5, which corresponds to the prolonged cell division and more enhanced hyper-transcription/translation in male primordial germ cells and their subsequent repression. Tricarboxylic acid cycle and one-carbon pathway are consistently upregulated in fetal male germ cells, suggesting their involvement in epigenetic changes preceding in males. Increased protein stability and oxidative phosphorylation during female germ cell differentiation suggests an upregulation of aerobic energy metabolism, which likely contributes to the proteostasis required for oocyte maturation in subsequent stages. The features elucidated in this study shed light on the unrevealed mechanisms of germ cell development.

Download Full-text

TEX14 Interacts with CEP55 To Block Cell Abscission

Molecular and Cellular Biology ◽

10.1128/mcb.01392-09 ◽

2010 ◽

Vol 30 (9) ◽

pp. 2280-2292 ◽

Cited By ~ 51

Author(s):

Tokuko Iwamori ◽

Naoki Iwamori ◽

Lang Ma ◽

Mark A. Edson ◽

Michael P. Greenbaum ◽

...

Keyword(s):

Germ Cell ◽

Germ Cells ◽

Intercellular Bridge ◽

Male Germ Cells ◽

Physical Separation ◽

Targeted Deletion ◽

Intercellular Bridges ◽

Daughter Cells ◽

Stable Component ◽

Evolutionarily Conserved

ABSTRACT In somatic cells, abscission, the physical separation of daughter cells at the completion of cytokinesis, requires CEP55, ALIX, and TSG101. In contrast, cytokinesis is arrested prior to abscission in differentiating male germ cells that are interconnected by TEX14-positive intercellular bridges. We have previously shown that targeted deletion of TEX14 disrupts intercellular bridges in all germ cells and causes male sterility. Although these findings demonstrate that intercellular bridges are essential for spermatogenesis, it remains to be shown how TEX14 and other proteins come together to prevent abscission and form stable intercellular bridges. Using a biochemical enrichment of male germ cell intercellular bridges, we identified additional bridge proteins, including CEP55. Although CEP55 is highly expressed in testes at the RNA level, there is no report of the presence of CEP55 in germ cells. We show here that CEP55 becomes a stable component of the intercellular bridge and that an evolutionarily conserved GPPX3Y motif of TEX14 binds strongly to CEP55 to block similar GPPX3Y motifs of ALIX and TSG101 from interacting and localizing to the midbody. Thus, TEX14 prevents the completion of cytokinesis by altering the destiny of CEP55 from a nidus for abscission to an integral component of the intercellular bridge.

Download Full-text

A cytoplasmic variant of the KH-type splicing regulatory protein serves as a decay-promoting factor for phosphoglycerate kinase 2 mRNA in murine male germ cells

Nucleic Acids Research ◽

10.1093/nar/gkn800 ◽

2008 ◽

Vol 36 (22) ◽

pp. 7157-7167 ◽

Cited By ~ 7

Author(s):

M. Xu ◽

J. R. McCarrey ◽

N. B. Hecht

Keyword(s):

Germ Cells ◽

Regulatory Protein ◽

Phosphoglycerate Kinase ◽

Male Germ Cells

Download Full-text

Induction of Bach1 and ARA70 gene expression at an early stage of adipocyte differentiation of mouse 3T3-L1 cells

Biochemical Journal ◽

10.1042/bj3610629 ◽

2002 ◽

Vol 361 (3) ◽

pp. 629-633 ◽

Cited By ~ 13

Author(s):

Makoto NISHIZUKA ◽

Tomoko TSUCHIYA ◽

Tsutomu NISHIHARA ◽

Masayoshi IMAGAWA

Keyword(s):

Gene Expression ◽

Transcription Factor ◽

Transcription Factors ◽

Adipocyte Differentiation ◽

Early Stage ◽

3T3 Cells ◽

Subtraction Method ◽

Proliferating Cells ◽

Genes Encoding ◽

Nih 3T3

Using a subtraction method, we have isolated genes that are induced early in the differentiation of mouse 3T3-L1 preadipocyte cells into adipocytes. These include the genes encoding transcription factors and signalling proteins, as well as unknown genes. Bach1, a transcription factor, and ARA70, a cofactor, were rapidly induced during differentiation. The induction of these two genes was observed only in growth-arrested 3T3-L1 cells, and not in proliferating cells. In NIH-3T3 cells, no induction was observed under either set of conditions. These results strongly indicate that Bach1 and ARA70 have valuable roles at the onset of adipocyte differentiation.

Download Full-text