Germ cell differentiation and proliferation in the developing testis of the South American plains viscacha, Lagostomus maximus (Mammalia, Rodentia)

Zygote ◽  
2011 ◽  
Vol 20 (3) ◽  
pp. 219-227 ◽  
Author(s):  
C.R. Gonzalez ◽  
M.L. Muscarsel Isla ◽  
N.A. Fraunhoffer ◽  
N.P. Leopardo ◽  
A.D. Vitullo
Keyword(s):  
Germ Cell ◽  
Germ Cells ◽  
Germ Line ◽  
Late Gestation ◽  
Nuclear Antigen ◽  
South American ◽  
The South ◽  
Pluripotency Marker ◽  
Germ Cell Differentiation ◽  
Lagostomus Maximus

SummaryCell proliferation and cell death are essential processes in the physiology of the developing testis that strongly influence the normal adult spermatogenesis. We analysed in this study the morphometry, the expression of the proliferation cell nuclear antigen (PCNA), cell pluripotency marker OCT-4, germ cell marker VASA and apoptosis in the developing testes of Lagostomus maximus, a rodent in which female germ line develops through abolished apoptosis and unrestricted proliferation. Morphometry revealed an increment in the size of the seminiferous cords with increasing developmental age, arising from a significant increase of PCNA-positive germ cells and a stable proportion of PCNA-positive Sertoli cells. VASA showed a widespread cytoplasmic distribution in a great proportion of proliferating gonocytes that increased significantly at late development. In the somatic compartment, Leydig cells increased at mid-development, whereas peritubular cells showed a stable rate of proliferation. In contrast to other mammals, OCT-4 positive gonocytes increased throughout development reaching 90% of germ cells in late-developing testis, associated with a conspicuous increase in circulating FSH from mid- to late-gestation. TUNEL analysis was remarkable negative, and only a few positive cells were detected in the somatic compartment. These results show that the South American plains viscacha displays a distinctive pattern of testis development characterized by a sustained proliferation of germ cells throughout development, with no signs of apoptosis cell demise, in a peculiar endocrine in utero ambiance that seems to promote the increase of spermatogonial number as a primary direct effect of FSH.

scholarly journals Quantification of healthy and atretic germ cells and follicles in the developing and post-natal ovary of the South American plains vizcacha, Lagostomus maximus: evidence of continuous rise of the germinal reserve

Reproduction ◽  
2014 ◽  
Vol 147 (2) ◽  
pp. 199-209 ◽  
Author(s):  
P I F Inserra ◽  
N P Leopardo ◽  
M A Willis ◽  
A L Freysselinard ◽  
A D Vitullo
Keyword(s):  
Germ Cell ◽  
Germ Cells ◽  
Germ Line ◽  
Cell Number ◽  
South American ◽  
The South ◽  
Foetal Life ◽  
Female Germ Line ◽  
Lagostomus Maximus ◽  
Mitotic Proliferation

The female germ line in mammals is subjected to massive cell death that eliminates 60–85% of the germinal reserve by birth and continues from birth to adulthood until the exhaustion of the germinal pool. Germ cell demise occurs mainly through apoptosis by means of a biased expression in favour of pro-apoptotic members of theBCL2gene family. By contrast, the South American plains vizcacha,Lagostomus maximus, exhibits sustained expression of the anti-apoptoticBCL2gene throughout gestation and a low incidence of germ cell apoptosis. This led to the proposal that, in the absence of death mechanisms other than apoptosis, the female germ line should increase continuously from foetal life until after birth. In this study, we quantified all healthy germ cells and follicles in the ovaries ofL. maximusfrom early foetal life to day 60 after birth using unbiased stereological methods and detected apoptosis by labelling with TUNEL assay. The healthy germ cell population increased continuously from early-developing ovary reaching a 50 times higher population number by the end of gestation. TUNEL-positive germ cells were <0.5% of the germ cell number, except at mid-gestation (3.62%). Mitotic proliferation, entrance into prophase I stage and primordial follicle formation occurred as overlapping processes from early pregnancy to birth. Germ cell number remained constant in early post-natal life, but a remnant population of non-follicular VASA- and PCNA-positive germ cells still persisted at post-natal day 60.L. maximusis the first mammal so far described in which female germ line develops in the absence of constitutive massive germ cell elimination.Free Spanish abstractSpanish translation of this abstract is freely available athttp://www.reproduction-online.org/content/147/2/199/suppl/DC1

scholarly journals The developing ovary of the South American plains vizcacha, Lagostomus maximus (Mammalia, Rodentia): massive proliferation with no sign of apoptosis-mediated germ cell attrition

Reproduction ◽  
2011 ◽  
Vol 141 (5) ◽  
pp. 633-641 ◽  
Author(s):  
N P Leopardo ◽  
F Jensen ◽  
M A Willis ◽  
M B Espinosa ◽  
A D Vitullo
Keyword(s):  
Germ Cell ◽  
Germ Cells ◽  
Ovarian Tissue ◽  
Tunel Assay ◽  
South American ◽  
Follicular Atresia ◽  
The South ◽  
Cell Degeneration ◽  
Lagostomus Maximus ◽  
Apoptotic Activity

Apoptosis-dependent massive germ cell death is considered a constitutive trait of the developing mammalian ovary that eliminates 65–85% of the germinal tissue depending on the species. After birth and during adult lifetime, apoptotic activity moves from the germ cell proper to the somatic compartment, decimating germ cells through follicular atresia until the oocyte reserve is exhausted. In contrast, the South American rodent Lagostomus maximus shows suppressed apoptosis-dependent follicular atresia in the adult ovary, with continuous folliculogenesis and massive polyovulation, which finally exhausts the oocyte pool. The absence of follicular atresia in adult L. maximus might arise from a failure to move apoptosis from the germinal stratum to the somatic compartment after birth or being a constitutive trait of the ovarian tissue with no massive germ cell degeneration in the developing ovary. We tested these possibilities by analysing oogenesis, expression of germ cell-specific VASA protein, apoptotic proteins BCL2 and BAX, and DNA fragmentation by TUNEL assay in the developing ovary of L. maximus. Immunolabelling for VASA revealed a massive and widespread colonisation of the ovary and proliferation of germ cells organised in nests that disappeared at late development when folliculogenesis began. No sign of germ cell attrition was found at any time point. BCL2 remained positive throughout oogenesis, whereas BAX was slightly detected in early development. TUNEL assay was conspicuously negative throughout the development. These results advocate for an unrestricted proliferation of germ cells, without apoptosis-driven elimination, as a constitutive trait of L. maximus ovary as opposed to what is normally found in the developing mammalian ovary.

scholarly journals Sox3 Functions in a Cell-Autonomous Manner to Regulate Spermatogonial Differentiation in Mice

Endocrinology ◽  
2011 ◽  
Vol 152 (4) ◽  
pp. 1606-1615 ◽  
Author(s):  
Monica M. Laronda ◽  
J. Larry Jameson
Keyword(s):  
Tyrosine Kinase ◽  
Germ Cell ◽  
Germ Cells ◽  
High Mobility ◽  
Nuclear Antigen ◽  
Gradual Transition ◽  
Tyrosine Kinase Receptor ◽  
Germ Cell Differentiation ◽  
Expression Of Genes ◽  
Complex Protein

Abstract The X-linked Sox3 gene encodes a member of the Sry high-mobility group box proteins, which play a role in many developmental processes including neurogenesis and testis development. This study further examined the role of Sox3 in spermatogenesis. Males without Sox3 expression exhibited a similar number of germ cell nuclear antigen-positive germ cells at 1, 5, and 10 d postpartum (dpp) compared to their wild-type littermates, but there was significant germ cell depletion by 20 dpp. However, spermatogenesis later resumed and postmeiotic germ cells were observed by 56 dpp. The VasaCre transgene was used to generate a germ cell-specific deletion of Sox3. The phenotype of the germ cell-specific Sox3 knockout was similar to the ubiquitous knockout, indicating an intrinsic role for Sox3 in germ cells. The residual germ cells in 20 dpp Sox3−/Y males were spermatogonia as indicated by their expression of neurogenin3 but not synaptonemal complex protein 3, which is expressed within cells undergoing meiosis. RNA expression analyses corroborated the histological analyses and revealed a gradual transition from relatively increased expression of spermatogonia genes at 20 dpp to near normal expression of genes characteristic of undifferentiated and meiotic germ cells by 84 dpp. Fluorescent-activated cell sorting of undifferentiated (ret tyrosine kinase receptor positive) and differentiated (kit receptor tyrosine kinase-positive) spermatogonia revealed depletion of differentiated spermatogonia in Sox3−/Y tubules. These results indicate that Sox3 functions in an intrinsic manner to promote differentiation of spermatogonia in prepubertal mice but it is not required for ongoing spermatogenesis in adults. The Sox3−/Y males provide a unique model for studying the mechanism of germ cell differentiation in prepubertal testes.

scholarly journals Characterization of Alternative Splicing (AS) Events during Chicken (Gallus gallus) Male Germ-Line Stem Cell Differentiation with Single-Cell RNA-seq

Animals ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 1469
Author(s):  
Changhua Sun ◽  
Kai Jin ◽  
Qisheng Zuo ◽  
Hongyan Sun ◽  
Jiuzhou Song ◽  
...  
Keyword(s):  
Stem Cells ◽  
Stem Cell ◽  
Alternative Splicing ◽  
Cell Differentiation ◽  
Germ Cell ◽  
Germ Cells ◽  
Germ Line ◽  
Rna Seq ◽  
Germ Cell Differentiation ◽  
Genome Wide

Alternative splicing (AS) is a ubiquitous, co-transcriptional, and post-transcriptional regulation mechanism during certain developmental processes, such as germ cell differentiation. A thorough understanding of germ cell differentiation will help us to open new avenues for avian reproduction, stem cell biology, and advances in medicines for human consumption. Here, based on single-cell RNA-seq, we characterized genome-wide AS events in manifold chicken male germ cells: embryonic stem cells (ESCs), gonad primordial germ cells (gPGCs), and spermatogonia stem cells (SSCs). A total of 38,494 AS events from 15,338 genes were detected in ESCs, with a total of 48,955 events from 14,783 genes and 49,900 events from 15,089 genes observed in gPGCs and SSCs, respectively. Moreover, this distribution of AS events suggests the diverse splicing feature of ESCs, gPGCs, and SSCs. Finally, several crucial stage-specific genes, such as NANOG, POU5F3, LIN28B, BMP4, STRA8, and LHX9, were identified in AS events that were transmitted in ESCs, gPGCs, and SSCs. The gene expression results of the RNA-seq data were validated by qRT-PCR. In summary, we provided a comprehensive atlas of the genome-wide scale of the AS event landscape in male chicken germ-line cells and presented its distribution for the first time. This research may someday improve treatment options for men suffering from male infertility.

scholarly journals Cell-type-specific regulation of genes involved in testicular lipid metabolism: fatty acid-binding proteins, diacylglycerol acyltransferases, and perilipin 2

Reproduction ◽  
2013 ◽  
Vol 146 (5) ◽  
pp. 471-480 ◽  
Author(s):  
Gerardo M Oresti ◽  
Jesús García-López ◽  
Marta I Aveldaño ◽  
Jesús del Mazo
Keyword(s):  
Fatty Acid ◽  
Cell Differentiation ◽  
Germ Cell ◽  
Germ Cells ◽  
Sertoli Cells ◽  
Fatty Acid Binding Proteins ◽  
Cell Type ◽  
Fatty Acid Binding ◽  
Germ Cell Differentiation ◽  
Perilipin 2

Male germ cell differentiation entails the synthesis and remodeling of membrane polar lipids and the formation of triacylglycerols (TAGs). This requires fatty acid-binding proteins (FABPs) for intracellular fatty acid traffic, a diacylglycerol acyltransferase (DGAT) to catalyze the final step of TAG biosynthesis, and a TAG storage mode. We examined the expression of genes encoding five members of the FABP family and two DGAT proteins, as well as the lipid droplet protein perilipin 2 (PLIN2), during mouse testis development and in specific cells from seminiferous epithelium.Fabp5expression was distinctive of Sertoli cells and consequently was higher in prepubertal than in adult testis. The expression ofFabp3increased in testis during postnatal development, associated with the functional differentiation of interstitial cells, but was low in germ cells.Fabp9, together withFabp12, was prominently expressed in the latter. Their transcripts increased from spermatocytes to spermatids and, interestingly, were highest in spermatid-derived residual bodies (RB). Both Sertoli and germ cells, which produce neutral lipids and store them in lipid droplets, expressedPlin2. Yet, whileDgat1was detected in Sertoli cells,Dgat2accumulated in germ cells with a similar pattern of expression asFabp9. These results correlated with polyunsaturated fatty acid-rich TAG levels also increasing with mouse germ cell differentiation highest in RB, connecting DGAT2 with the biosynthesis of such TAGs. The age- and germ cell type-associated increases inFabp9,Dgat2, andPlin2levels are thus functionally related in the last stages of germ cell differentiation.

ERα and GnRH co-localize in the hypothalamic neurons of the South American plains vizcacha, Lagostomus maximus (Rodentia, Caviomorpha)

2017 ◽  
Vol 48 (3) ◽  
pp. 259-273 ◽  
Author(s):  
Pablo Ignacio Felipe Inserra ◽  
Santiago Elías Charif ◽  
Noelia Paula Di Giorgio ◽  
Lucía Saucedo ◽  
Alejandro Raúl Schmidt ◽  
...  
Keyword(s):  
South American ◽  
The South ◽  
Hypothalamic Neurons ◽  
Lagostomus Maximus

Distribution of kisspeptin system and its relation with gonadotropin-releasing hormone in the hypothalamus of the South American plains vizcacha, Lagostomus maximus

2021 ◽  
pp. 113974
Author(s):  
Alejandro Raúl Schmidt ◽  
Pablo Ignacio Felipe Inserra ◽  
Santiago Andrés Cortasa ◽  
Sofía Proietto ◽  
Victoria Fidel ◽  
...  
Keyword(s):  
Gonadotropin Releasing Hormone ◽  
South American ◽  
The South ◽  
Releasing Hormone ◽  
Lagostomus Maximus

scholarly journals Interactome analyses reveal profound proteasome structural and functional rearrangements throughout mammalian spermatogenesis

2021 ◽  
Author(s):  
Dusan Zivkovic ◽  
Angelique Sanchez Dafun ◽  
Thomas Menneteau ◽  
Adrien Schahl ◽  
Sandrine Lise ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Germ Cell ◽  
Germ Cells ◽  
Protein Assembly ◽  
Homologous Chromosomes ◽  
High Proteolytic Activity ◽  
Complex Processes ◽  
Germ Cell Differentiation ◽  
Mechanism Function

During spermatogenesis, spermatogonia undergo a series of mitotic and meiotic divisions on their path to spermatozoa. To achieve this, a succession of complex processes requiring high proteolytic activity are in part orchestrated by the proteasome. The spermatoproteasome (s20S) is a proteasome subtype specific to the developing gametes, in which the gamete-specific α4s subunit replaces the α4 isoform found in the constitutive proteasome (c20S). Although the s20S is conserved across species and was shown to be crucial for germ cell development, its mechanism, function and structure remain incompletely characterized. Here, we used advanced mass spectrometry (MS) methods to map the composition of proteasome complexes and their interactomes throughout spermatogenesis. We observed that the s20S becomes highly activated as germ cells enter meiosis, mainly through association with proteasome activators PA200 and 19S. Additionally, the proteasome population shifts from predominantly c20S (98%) to predominantly s20S (>82-92%) during differentiation, presumably due to the shift from α4 to α4s expression. We confirmed that s20S, but not c20S, interacts with components of the synaptonemal complex, the multi-protein assembly that connects homologous chromosomes during meiosis. In vitro, s20S preferentially bind to 19S, and displayed higher trypsin- and chymotrypsin-like activities, both with and without PA200 activation. Moreover, using MS methods to monitor protein dynamics, we identified significant differences in domain flexibility between α4 and α4s. We propose that these differences induced by α4s incorporation result in significant changes in the way the s20S interacts with its partners, and dictate its role in germ cell differentiation.

Melatonin is involved in the modulation of the hypothalamic and pituitary activity in the South American plains vizcacha, Lagostomus maximus

2021 ◽  
Author(s):  
Santiago Elías Charif ◽  
Pablo Ignacio Felipe Inserra ◽  
Alejandro Raúl Schmidt ◽  
Santiago Andrés Cortasa ◽  
Sofía Proietto ◽  
...  
Keyword(s):  
South American ◽  
The South ◽  
Lagostomus Maximus

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

2019 ◽  
Vol 2019 ◽  
pp. 1-8
Author(s):  
Min Chen ◽  
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.

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