scholarly journals Molecular signatures to define spermatogenic cells in common marmoset (Callithrix jacchus)

Reproduction ◽  
2012 ◽  
Vol 143 (5) ◽  
pp. 597-609 ◽  
Author(s):  
Zachary Yu-Ching Lin ◽  
Masanori Imamura ◽  
Chiaki Sano ◽  
Ryusuke Nakajima ◽  
Tomoko Suzuki ◽  
...  
Keyword(s):  
Germ Cell ◽  
Reproductive Biology ◽  
Germ Cells ◽  
Methylation Status ◽  
Common Marmoset ◽  
Methylation Pattern ◽  
Callithrix Jacchus ◽  
Molecular Signatures ◽  
Spermatogenic Cells ◽  
Human Reproductive

Germ cell development is a fundamental process required to produce offspring. The developmental program of spermatogenesis has been assumed to be similar among mammals. However, recent studies have revealed differences in the molecular properties of primate germ cells compared with the well-characterized mouse germ cells. This may prevent simple application of rodent insights into higher primates. Therefore, thorough investigation of primate germ cells is necessary, as this may lead to the development of more appropriate animal models. The aim of this study is to define molecular signatures of spermatogenic cells in the common marmoset, Callithrix jacchus. Interestingly, NANOG, PRDM1, DPPA3 (STELLA), IFITM3, and ZP1 transcripts, but no POU5F1 (OCT4), were detected in adult marmoset testis. Conversely, mouse testis expressed Pou5f1 but not Nanog, Prdm1, Dppa3, Ifitm3, and Zp1. Other previously described mouse germ cell markers were conserved in marmoset and mouse testes. Intriguingly, marmoset spermatogenic cells underwent dynamic protein expression in a developmental stage-specific manner; DDX4 (VASA) protein was present in gonocytes, diminished in spermatogonial cells, and reexpressed in spermatocytes. To investigate epigenetic differences between adult marmoset and mice, DNA methylation analyses identified unique epigenetic profiles to marmoset and mice. Marmoset NANOG and POU5F1 promoters in spermatogenic cells exhibited a methylation status opposite to that in mice, while the DDX4 and LEFTY1 loci, as well as imprinted genes, displayed an evolutionarily conserved methylation pattern. Marmosets have great advantages as models for human reproductive biology and are also valuable as experimental nonhuman primates; thus, the current study provides an important platform for primate reproductive biology, including possible applications to humans.

Examination of the dynamics of global DNA methylation pattern establishment during spermatogenesiss

2007 ◽  
Vol 30 (4) ◽  
pp. 90
Author(s):  
Kirsten Niles ◽  
Sophie La Salle ◽  
Christopher Oakes ◽  
Jacquetta Trasler
Keyword(s):  
Dna Methylation ◽  
Germ Cell ◽  
Germ Cells ◽  
Epigenetic Modification ◽  
Methylation Pattern ◽  
Chromosome 9 ◽  
Specific Gene ◽  
Global Methylation ◽  
Dna Methylation Pattern ◽  
Methylation Patterns

Background: DNA methylation is an epigenetic modification involved in gene expression, genome stability, and genomic imprinting. In the male, methylation patterns are initially erased in primordial germ cells (PGCs) as they enter the gonadal ridge; methylation patterns are then acquired on CpG dinucleotides during gametogenesis. Correct pattern establishment is essential for normal spermatogenesis. To date, the characterization and timing of methylation pattern acquisition in PGCs has been described using a limited number of specific gene loci. This study aimed to describe DNA methylation pattern establishment dynamics during male gametogenesis through global methylation profiling techniques in a mouse model. Methods: Using a chromosome based approach, primers were designed for 24 regions spanning chromosome 9; intergenic, non-repeat, non-CpG island sequences were chosen for study based on previous evidence that these types of sequences are targets for testis-specific methylation events. The percent methylation was determined in each region by quantitative analysis of DNA methylation using real-time PCR (qAMP). The germ cell-specific pattern was determined by comparing methylation between spermatozoa and liver. To examine methylation in developing germ cells, spermatogonia from 2 day- and 6 day-old Oct4-GFP (green fluorescent protein) mice were isolated using fluorescence activated cell sorting. Results: As compared to liver, four loci were hypomethylated and five loci were hypermethylated in spermatozoa, supporting previous results indicating a unique methylation pattern in male germ cells. Only one region was hypomethylated and no regions were hypermethylated in day 6 spermatogonia as compared to mature spermatozoa, signifying that the bulk of DNA methylation is established prior to type A spermatogonia. The methylation in day 2 spermatogonia, germ cells that are just commencing mitosis, revealed differences of 15-20% compared to day 6 spermatogonia at five regions indicating that the most crucial phase of DNA methylation acquisition occurs prenatally. Conclusion: Together, these studies provide further evidence that germ cell methylation patterns differ from those in somatic tissues and suggest that much of methylation at intergenic sites is acquired during prenatal germ cell development. (Supported by CIHR)

scholarly journals Germ cell dynamics in the testis of the postnatal common marmoset monkey (Callithrix jacchus)

Reproduction ◽  
2010 ◽  
Vol 140 (5) ◽  
pp. 733-742 ◽  
Author(s):  
S Albert ◽  
J Ehmcke ◽  
J Wistuba ◽  
K Eildermann ◽  
R Behr ◽  
...  
Keyword(s):  
Stem Cell ◽  
Germ Cell ◽  
Germ Cells ◽  
Callithrix Jacchus ◽  
Marker Genes ◽  
Preclinical Model ◽  
Cell Physiology ◽  
Testicular Development ◽  
Testis Size ◽  
Qrt Pcr

The seminiferous epithelium in the nonhuman primate Callithrix jacchus is similarly organized to man. This monkey has therefore been used as a preclinical model for spermatogenesis and testicular stem cell physiology. However, little is known about the developmental dynamics of germ cells in the postnatal primate testis. In this study, we analyzed testes of newborn, 8-week-old, and adult marmosets employing immunohistochemistry using pluripotent stem cell and germ cell markers DDX4 (VASA), POU5F1 (OCT3/4), and TFAP2C (AP-2γ). Stereological and morphometric techniques were applied for quantitative analysis of germ cell populations and testicular histological changes. Quantitative RT-PCR (qRT-PCR) of testicular mRNA was applied using 16 marker genes establishing the corresponding profiles during postnatal testicular development. Testis size increased during the first 8 weeks of life with the main driver being longitudinal outgrowth of seminiferous cords. The number of DDX4-positive cells per testis doubled between birth and 8 weeks of age whereas TFAP2C- and POU5F1-positive cells remained unchanged. This increase in DDX4-expressing cells indicates dynamic growth of the differentiated A-spermatogonial population. The presence of cells expressing POU5F1 and TFAP2C after 8 weeks reveals the persistence of less differentiated germ cells. The mRNA and protein profiles determined by qRT-PCR and western blot in newborn, 8-week-old, and adult marmosets corroborated the immunohistochemical findings. In conclusion, we demonstrated the presence of distinct spermatogonial subpopulations in the primate testis exhibiting different dynamics during early testicular development. Our study demonstrates the suitability of the marmoset testis as a model for human testicular development.

Protein–glycolipid interactions during spermatogenesis. Binding of specific germ cell proteins to sulfatoxygalactosylacylalkylglycerol, the major glycolipid of mammalian male germ cells

1985 ◽  
Vol 63 (10) ◽  
pp. 1077-1085 ◽  
Author(s):  
C. A. Lingwood
Keyword(s):  
Germ Cell ◽  
Germ Cells ◽  
Plasma Membranes ◽  
Specific Binding ◽  
Immune Serum ◽  
Spermatogenic Cells ◽  
Molecular Weights ◽  
Testicular Spermatozoa ◽  
Antibody Staining ◽  
A New Technique

Specific binding of membrane proteins extracted from rat spermatogenic cells to the major glycolipid of the male germ cell has been demonstrated by affinity chromatography. A new method for the production of affinity matrices, using photoactivatable heterobifunctional cross-linking agents, has been used to immobilize sulfatoxygalactosylacylalkylglycerol. Three proteins of apparent molecular weights 68 000, 34 000, and 24 000 from spermatogenic cells have been shown to selectively and reversibly bind to this affinity matrix. Antiserum raised against the major of these species (68 000) was demonstrated to be specific for this protein by immunoblotting. A new technique for the reduction of background nonspecific antibody staining using this method is described. The immune serum has been used to localize the antigen in frozen testicular sections. The protein is present in the plasma membranes of all germ cells, but the expression is elevated for testicular spermatozoa and cells in or near the basal compartment of the seminiferous epithelium. The relevance of these findings to intercellular communication and spermatogenesis is discussed.

scholarly journals Somatic regulation of female germ cell regeneration and development in planarians

2021 ◽  
Author(s):  
Umair W. Khan ◽  
Phillip A Newmark
Keyword(s):  
Germ Cell ◽  
Germ Cells ◽  
Pluripotent Stem Cells ◽  
Cell Development ◽  
Molecular Signatures ◽  
Germ Cell Development ◽  
Ovarian Cells ◽  
Planarian Regeneration ◽  
Female Germ Cell ◽  
Oocyte Differentiation

Female germ cells develop into oocytes, with the capacity for totipotency. In most animals, these remarkable cells are specified during development and cannot be regenerated. By contrast, planarians, known for their regenerative prowess, can regenerate germ cells. To uncover mechanisms required for female germ cell development and regeneration, we generated gonad-specific transcriptomes and identified genes whose expression defines progressive stages of female germ cell development. Strikingly, early female germ cells share molecular signatures with the pluripotent stem cells driving planarian regeneration. We uncovered spatial heterogeneity within somatic ovarian cells and found that a regionally enriched FoxL homolog is required for oocyte differentiation, but not specification, suggestive of functionally distinct somatic compartments. Unexpectedly, a neurotransmitter-biosynthetic enzyme, AADC, is also expressed in somatic gonadal cells, and plays opposing roles in female and male germ cell development. Thus, somatic gonadal cells deploy conserved factors to regulate germ cell development and regeneration in planarians.

Mouse embryonic germ (EG) cell lines: transmission through the germline and differences in the methylation imprint of insulin-like growth factor 2 receptor (Igf2r) gene compared with embryonic stem (ES) cell lines

Development ◽  
1994 ◽  
Vol 120 (11) ◽  
pp. 3197-3204 ◽  
Author(s):  
P.A. Labosky ◽  
D.P. Barlow ◽  
B.L. Hogan
Keyword(s):  
Growth Factor ◽  
Germ Cell ◽  
Cell Lines ◽  
Germ Cells ◽  
Coat Color ◽  
Primordial Germ Cells ◽  
Methylation Status ◽  
Embryonic Stem ◽  
Insulin Like Growth Factor ◽  
Significant Difference

Primordial germ cells of the mouse cultured on feeder layers with leukemia inhibitory factor, Steel factor and basic fibroblast growth factor give rise to cells that resemble undifferentiated blastocyst-derived embryonic stem cells. These primordial germ cell-derived embryonic germ cells can be induced to differentiate extensively in culture, form teratocarcinomas when injected into nude mice and contribute to chimeras when injected into host blastocysts. Here, we report the derivation of multiple embryonic germ cell lines from 8.5 days post coitum embryos of C57BL/6 inbred mice. Four independent embryonic germ cell lines with normal male karyotypes have formed chimeras when injected into BALB/c host blastocysts and two of these lines have transmitted coat color markers through the germline. We also show that pluripotent cell lines capable of forming teratocarcinomas and coat color chimeras can be established from primordial germ cells of 8.0 days p.c. embryos and 12.5 days p.c. genital ridges. We have examined the methylation status of the putative imprinting box of the insulin-like growth factor type 2 receptor gene (Igf2r) in these embryonic germ cell lines. No correlation was found between methylation pattern and germline competence. A significant difference was observed between embryonic stem cell and embryonic germ cell lines in their ability to maintain the methylation imprint of the Igf2r gene in culture. This may illustrate a fundamental difference between these two cell types.

scholarly journals In Vivo Epigenomic Profiling of Germ Cells Reveals Germ Cell Molecular Signatures

2013 ◽  
Vol 24 (3) ◽  
pp. 324-333 ◽  
Author(s):  
Jia-Hui Ng ◽  
Vibhor Kumar ◽  
Masafumi Muratani ◽  
Petra Kraus ◽  
Jia-Chi Yeo ◽  
...  
Keyword(s):  
Germ Cell ◽  
Germ Cells ◽  
Molecular Signatures

241 METHYLATION PROFILE OF XIST GENE EXON 1 IN BOVINE SPERMATOGENIC CELLS

2013 ◽  
Vol 25 (1) ◽  
pp. 268
Author(s):  
R. C. Nishimura ◽  
I. R. Bessa ◽  
M. A. N. Dode ◽  
M. M. Franco
Keyword(s):  
Germ Cells ◽  
Methylation Pattern ◽  
Methylation Profile ◽  
Epigenetic Reprogramming ◽  
Xist Gene ◽  
Head Group ◽  
Spermatogenic Cells ◽  
Significance Level ◽  
Exon 1 ◽  
Gene Exon

Mammalian embryos undergo two waves of genome reprogramming, the first in the zygote, when paternal and maternal genomes are demethylated and, shortly thereafter, remethylated, and the second in the primordial germ cells. It is believed that remethylation is reestablished in male germ cells before birth; however, it is not clear when and how this process occurs in the bovine. Thus, this work aimed to verify whether epigenetic reprogramming occurs during spermatogenesis by evaluating the methylation profile of XIST gene exon 1 in different spermatogenic cells. Spermatocytes, elongated spermatids, and spermatozoa from the epididymis head and tail were collected from bovine testes obtained from a slaughterhouse. The DNA was extracted from the collected cells and treated with bisulfite. The treated DNA was amplified through nested PCR, and the product was inserted on a vector and cloned in bacteria. The plasmid DNA was extracted and sequenced. The sequences of the experiment were compared with the sequence of XIST gene from GenBank, and those that presented a bisulfite conversion rate of ≥95% and a homology of ≥97% with the sequence from GenBank were used. To compare the methylation pattern among groups, the total percentage of methylated CpG was calculated in each replicate and each group. The methylation pattern was compared using Kruskal-Wallis and Mann–Whitney tests because the data did not show normality. All data were compared using the Prophet Program, version 5.0 (1996; BBN Systems and Technologies, Cambridge, MA, USA), and are shown as the mean ± SEM. The significance level used was P < 0.05. The spermatocytes, elongated spermatids, and spermatozoa from the epididymis head and tail groups presented 15.70 ± 14.54%, 1.96 ± 1.96%, 74.09 ± 6.78%, and 45.09 ± 20.19% of methylation, respectively. The epididymis head group was more methylated than the spermatocyte and elongated spermatid groups (P < 0.01). When arranged in two groups, one with spermatocytes and elongated spermatids, and the other with epididymidal spermatozoa, and compared, it was observed that the methylation level was different (P < 0.01) between them. These results suggest that epigenetic reprogramming is still occurring during spermatozoa formation.

sp42, the boar sperm tyrosine kinase, is a male germ cell-specific product with a highly conserved tissue expression extending to other mammalian species

1996 ◽  
Vol 109 (4) ◽  
pp. 851-858
Author(s):  
G. Berruti ◽  
B. Borgonovo
Keyword(s):  
Tyrosine Kinase ◽  
Western Blot ◽  
Germ Cell ◽  
Molecular Mass ◽  
Germ Cells ◽  
Mammalian Species ◽  
Tissue Expression ◽  
Spermatogenic Cells ◽  
Male Germ Cells ◽  
Boar Spermatozoa

sp42, a tyrosine kinase of 42 kDa originally found in ejaculated boar spermatozoa, is so far the only tyrosine protein kinase to have been purified from mature male germ cells. We have developed and characterized rabbit polyclonal antibodies specifically directed against the boar sperm enzyme, which has been here purified to homogeneity. Anti-sp42 serum and sp42 affinity-purified antibodies work very well in western blot, immunoprecipitation and immunocytochemistry, and do not inhibit sp42 catalytic activity. Immunoblotting analyses reveal the presence of sp42 both in maturing boar epididymal (caput, corpus and cauda segment) spermatozoa and in testicular spermatogenic cells, thus establishing that the protein is effectively expressed in the germ cells and is not a sperm-associated protein secreted by the epididymal epithelium or male accessory glands. This finding is further strengthened by the fact that sp42 is not glycosylated, since different lectins fail to bind to sp42 and treatment of sp42 with different deglycosylation enzymes does not result in a reduction of the molecular mass of sp42. When different boar tissues are immunoscreened in western blot analysis, the results are all sp42-negative. The extension of the study to other mammalian species (human, mouse and rat) demonstrates that proteins immunologically related to boar sp42, which share the same molecular mass and tyrosine kinase activity, are both expressed in spermatogenic cells and maintained in mature sperm cells. Intriguingly, when a wide spectrum of somatic mouse and rat tissues is probed with sp42-antiserum, no tissue presents anti-sp42 immunoreactivity. Immunocytochemistry shows that in boar spermatozoa sp42 is confined to the tail mid-piece, while by immunohistochemistry carried out on sections of adult rat testis the appearance time of the kinase appears to be consistent with a post-meiotic synthesis in haploid spermatids. Altogether, these results demonstrate that boar sp42 is a new male germ cell-specific gene product, with highly conserved tissue expression extended to other mammalian species, and suggest a possible role played by the cytoplasmic tyrosine kinase in the cell signalling network specific to haploid male germ cells.

scholarly journals Transcription factors protect from DNA re-methylation during reprograming of primordial germ cells and pre-implantation embryos

2019 ◽  
Author(s):  
Isaac Kremsky ◽  
Victor G. Corces
Keyword(s):  
Dna Methylation ◽  
Transcription Factors ◽  
Germ Cell ◽  
Germ Cells ◽  
Primordial Germ Cells ◽  
Methylation Status ◽  
Primordial Germ Cell ◽  
Cell Mass ◽  
Phenotypic Traits ◽  
Epigenetic Information

AbstractA growing body of evidence suggests that certain phenotypic traits of epigenetic origin can be passed across generations via both the male and female germlines of mammals. These observations have been difficult to explain owing to a global loss of the majority of known epigenetic marks present in parental chromosomes during primordial germ cell development and after fertilization. By integrating previously published BS-seq, DNase-seq, ATAC-seq, and RNA-seq data collected during multiple stages of primordial germ cell and preimplantation development, we find that the methylation status of the majority of CpGs genome-wide is restored after global reprogramming, despite the fact that global CpG methylation drops to 10% in primordial germ cells and 20% in the inner cell mass of the blastocyst. We estimate the proportion of such CpGs with preserved methylation status to be 78%. Further, we find that CpGs at sites bound by transcription factors during the global re-methylation phases of germ line and embryonic development remain hypomethylated across all developmental stages observed. On the other hand, CpGs at sites not bound by transcription factors during the global re-methylation phase have high methylation levels prior to global de-methylation, become de-methylated during global de-methylation, and then become re-methylated. The results suggest that transcription factors can act as carriers of epigenetic information during germ cell and pre-implantation development by ensuring that the methylation status of CpGs is maintained after reprogramming of DNA methylation. Based on our findings, we propose a model in which transcription factor binding during the re-methylation phases of primordial germ cell and pre-implantation development allow epigenetic information to be maintained trans-generationally even at sites where DNA methylation is lost during global de-methylation.

Electron microscope study of the effects of radiation on insect fertility

1990 ◽  
Vol 48 (3) ◽  
pp. 72-73
Author(s):  
Judy Ju-Hu Chiang ◽  
Robert Kuo-Cheng Chen
Keyword(s):  
Electron Microscopy ◽  
Germ Cell ◽  
Germ Cells ◽  
Electron Microscope Study ◽  
Radiation Treatment ◽  
Light And Electron Microscopy ◽  
Stem Borer ◽  
Metabolic Energy ◽  
Rice Stem Borer ◽  
Effects Of Radiation

Germ cells from the rice stem borer Chilo suppresalis, were examined by light and electron microscopy. Damages to organelles within the germ cells were observed. The mitochondria, which provide the cell with metabolic energy, were seen to disintegrate within the germ cell. Lysosomes within the germ cell were also seen to disintegrate. The subsequent release of hydrolytic enzymesmay be responsible for the destruction of organelles within the germ cell. Insect spermatozoa were seen to lose the ability to move because of radiation treatment. Damage to the centrioles, one of which is in contact with the tail, may be involved in causing sperm immobility.

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