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Manku G, Kong CC, Culty M. Role of the Ubiquitin Ligase RNF149 in the Development of Rat Neonatal Gonocytes. Front Endocrinol (Lausanne) 2022; 13:896507. [PMID: 35634494 PMCID: PMC9136010 DOI: 10.3389/fendo.2022.896507] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Accepted: 04/11/2022] [Indexed: 11/13/2022] Open
Abstract
Male reproductive function depends on the formation of spermatogonial stem cells from their neonatal precursors, the gonocytes. Previously, we identified several UPS enzymes dynamically altered during gonocyte differentiation. The present work focuses on understanding the role of the RING finger protein 149 (RNF149), an E3 ligase that we found to be strongly expressed in gonocytes and downregulated in spermatogonia. The quantification of RNF149 mRNA from postnatal day (PND) 2 to 35 (puberty) in rat testis, brain, liver, kidney, and heart indicated that its highest levels are found in the testis. RNF149 knock-down in PND3 rat gonocytes was performed to better understand its role in gonocyte development. While a proliferative cocktail of PDGF-BB and 17β-estradiol (P+E) increased both the expression levels of the cell proliferation marker PCNA and RNF149 in mock cells, the effects of P+E on both genes were reduced in cells treated with RNF149 siRNA, suggesting that RNF149 expression is regulated during gonocyte proliferation and that there might be a functional link between RNF149 and PCNA. To examine RNF149 subcellular localization, EGFP-tagged RNF149 vectors were constructed, after determining the rat testis RNF149 mRNA sequence. Surprisingly, two variant transcripts were expressed in rat tissues, predicting truncated proteins, one containing the PA and the other the RING functional domains. Transfection in mouse F9 embryonal carcinoma cells and C18-4 spermatogonial cell lines showed differential subcellular profiles of the two truncated proteins. Overall, the results of this study support a role for RNF149 in gonocyte proliferation and suggest its transcription to variant mRNAs resulting in two proteins with different functional domains. Future studies will examine the respective roles of these variant proteins in the cell lines and isolated gonocytes.
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Affiliation(s)
- Gurpreet Manku
- The Research Institute of the McGill University Health Centre, McGill University, Montreal, QC, Canada
- The Departments of Medicine and Pharmacology & Therapeutics, McGill University, Montreal, QC, Canada
| | - Chi-Chon Kong
- The Research Institute of the McGill University Health Centre, McGill University, Montreal, QC, Canada
- The Departments of Medicine and Pharmacology & Therapeutics, McGill University, Montreal, QC, Canada
| | - Martine Culty
- The Research Institute of the McGill University Health Centre, McGill University, Montreal, QC, Canada
- The Departments of Medicine and Pharmacology & Therapeutics, McGill University, Montreal, QC, Canada
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, United States
- *Correspondence: Martine Culty,
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O’Flaherty C, Boisvert A, Manku G, Culty M. Protective Role of Peroxiredoxins against Reactive Oxygen Species in Neonatal Rat Testicular Gonocytes. Antioxidants (Basel) 2019; 9:antiox9010032. [PMID: 31905831 PMCID: PMC7022870 DOI: 10.3390/antiox9010032] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Revised: 12/23/2019] [Accepted: 12/25/2019] [Indexed: 12/27/2022] Open
Abstract
Peroxiredoxins (PRDXs) are antioxidant enzymes that protect cells from oxidative stress and play a role in reactive oxygen species (ROS)-mediated signaling. We reported that PRDXs are critical for human fertility by maintaining sperm viability and regulating ROS levels during capacitation. Moreover, studies on Prdx6−/− mice revealed the essential role of PRDX6 in the viability, motility, and fertility competence of spermatozoa. Although PRDXs are abundant in the testis and spermatozoa, their potential role at different phases of spermatogenesis and in perinatal germ cells is unknown. Here, we examined the expression and role of PRDXs in isolated rat neonatal gonocytes, the precursors of spermatogonia, including spermatogonial stem cells. Gene array, qPCR analyses showed that PRDX1, 2, 3, 5, and 6 transcripts are among the most abundant antioxidant genes in postnatal day (PND) 3 gonocytes, while immunofluorescence confirmed the expression of PRDX1, 2, and 6 proteins. The role of PRDXs in gonocyte viability was examined using PRDX inhibitors, revealing that the 2-Cys PRDXs and PRDX6 peroxidases activities are critical for gonocytes viability in basal condition, likely preventing an excessive accumulation of endogenous ROS in the cells. In contrast to its crucial role in spermatozoa, PRDX6 independent phospholipase A2 (iPLA2) activity was not critical in gonocytes in basal conditions. However, under conditions of H2O2-induced oxidative stress, all these enzymatic activities were critical to maintain gonocyte viability. The inhibition of PRDXs promoted a two-fold increase in lipid peroxidation and prevented gonocyte differentiation. These results suggest that ROS are produced in neonatal gonocytes, where they are maintained by PRDXs at levels that are non-toxic and permissive for cell differentiation. These findings show that PRDXs play a major role in the antioxidant machinery of gonocytes, to maintain cell viability and allow for differentiation.
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Affiliation(s)
- Cristian O’Flaherty
- The Research Institute of the McGill University Health Centre, Montreal, QC H4A 3J1, Canada; (C.O.); (A.B.); (G.M.)
- Department of Surgery (Urology Division), McGill University, Montreal, QC H4A 3J1, Canada
| | - Annie Boisvert
- The Research Institute of the McGill University Health Centre, Montreal, QC H4A 3J1, Canada; (C.O.); (A.B.); (G.M.)
| | - Gurpreet Manku
- The Research Institute of the McGill University Health Centre, Montreal, QC H4A 3J1, Canada; (C.O.); (A.B.); (G.M.)
- Department of Medicine, McGill University, Montreal, QC H4A 3J1, Canada
| | - Martine Culty
- The Research Institute of the McGill University Health Centre, Montreal, QC H4A 3J1, Canada; (C.O.); (A.B.); (G.M.)
- Department of Medicine, McGill University, Montreal, QC H4A 3J1, Canada
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California School of Pharmacy, Los Angeles, CA 90089, USA
- Correspondence: ; Tel.: +1-323-865-1677
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Manku G, Papadopoulos P, Boisvert A, Culty M. Cyclooxygenase 2 (COX2) expression and prostaglandin synthesis in neonatal rat testicular germ cells: Effects of acetaminophen and ibuprofen. Andrology 2019; 8:691-705. [DOI: 10.1111/andr.12727] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Revised: 11/04/2019] [Accepted: 11/04/2019] [Indexed: 12/01/2022]
Affiliation(s)
- Gurpreet Manku
- The Research Institute of the McGill University Health Centre Montreal QC Canada
- Department of Medicine McGill University Montreal QC Canada
| | - Philippos Papadopoulos
- The Research Institute of the McGill University Health Centre Montreal QC Canada
- Department of Regulatory and Quality Sciences School of Pharmacy University of Southern California Los Angeles CA USA
| | - Annie Boisvert
- The Research Institute of the McGill University Health Centre Montreal QC Canada
- Department of Medicine McGill University Montreal QC Canada
| | - Martine Culty
- The Research Institute of the McGill University Health Centre Montreal QC Canada
- Department of Medicine McGill University Montreal QC Canada
- Department of Pharmacology and Pharmaceutical Sciences School of Pharmacy University of Southern California Los Angeles CA USA
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Bose R, Sheng K, Moawad AR, Manku G, O'Flaherty C, Taketo T, Culty M, Fok KL, Wing SS. Ubiquitin Ligase Huwe1 Modulates Spermatogenesis by Regulating Spermatogonial Differentiation and Entry into Meiosis. Sci Rep 2017; 7:17759. [PMID: 29259204 PMCID: PMC5736635 DOI: 10.1038/s41598-017-17902-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2017] [Accepted: 12/01/2017] [Indexed: 12/02/2022] Open
Abstract
Spermatogenesis consists of a series of highly regulated processes that include mitotic proliferation, meiosis and cellular remodeling. Although alterations in gene expression are well known to modulate spermatogenesis, posttranscriptional mechanisms are less well defined. The ubiquitin proteasome system plays a significant role in protein turnover and may be involved in these posttranscriptional mechanisms. We previously identified ubiquitin ligase Huwe1 in the testis and showed that it can ubiquitinate histones. Since modulation of histones is important at many steps in spermatogenesis, we performed a complete characterization of the functions of Huwe1 in this process by examining the effects of its inactivation in the differentiating spermatogonia, spermatocytes and spermatids. Inactivation of Huwe1 in differentiating spermatogonia led to their depletion and formation of fewer pre-leptotene spermatocytes. The cell degeneration was associated with an accumulation of DNA damage response protein γH2AX, impaired downstream signalling and apoptosis. Inactivation of Huwe1 in spermatocytes indicated that Huwe1 is not essential for meiosis and spermiogenesis, but can result in accumulation of γH2AX. Collectively, these results provide a comprehensive survey of the functions of Huwe1 in spermatogenesis and reveal Huwe1’s critical role as a modulator of the DNA damage response pathway in the earliest steps of spermatogonial differentiation.
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Affiliation(s)
- Rohini Bose
- The Research Institute of the McGill University Health Centre, Montréal, Québec, Canada.,Department of Medicine, McGill University, Montréal, Québec, Canada
| | - Kai Sheng
- The Research Institute of the McGill University Health Centre, Montréal, Québec, Canada.,Department of Medicine, McGill University, Montréal, Québec, Canada
| | - Adel R Moawad
- The Research Institute of the McGill University Health Centre, Montréal, Québec, Canada.,Department of Surgery, McGill University, Montréal, Québec, Canada.,Department of Theriogenology, Faculty of Veterinary Medicine, Cairo University, Giza, Egypt
| | - Gurpreet Manku
- The Research Institute of the McGill University Health Centre, Montréal, Québec, Canada.,Department of Medicine, McGill University, Montréal, Québec, Canada.,Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec, Canada
| | - Cristian O'Flaherty
- The Research Institute of the McGill University Health Centre, Montréal, Québec, Canada.,Department of Surgery, McGill University, Montréal, Québec, Canada.,Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec, Canada
| | - Teruko Taketo
- The Research Institute of the McGill University Health Centre, Montréal, Québec, Canada.,Department of Surgery, McGill University, Montréal, Québec, Canada.,Department of Obstetrics and Gynecology, McGill University, Montréal, Québec, Canada.,Department of Biology, McGill University, Montréal, Québec, Canada
| | - Martine Culty
- The Research Institute of the McGill University Health Centre, Montréal, Québec, Canada.,Department of Medicine, McGill University, Montréal, Québec, Canada.,Dept. of Pharmacology, University of Southern California, Los Angeles, California, USA
| | - Kin Lam Fok
- The Research Institute of the McGill University Health Centre, Montréal, Québec, Canada.,Department of Medicine, McGill University, Montréal, Québec, Canada.,Epithelial Cell Biology Research Center, School of Biomedical Sciences, The Faculty of Medicine, The Chinese University of Hong Kong, Sha Tin, Hong Kong.,Shenzhen Research Institute, The Chinese University of Hong Kong - Shenzhen, Shenzhen, China
| | - Simon S Wing
- The Research Institute of the McGill University Health Centre, Montréal, Québec, Canada. .,Department of Medicine, McGill University, Montréal, Québec, Canada.
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Manku G, Hueso A, Brimo F, Chan P, Gonzalez-Peramato P, Jabado N, Gayden T, Bourgey M, Riazalhosseini Y, Culty M. Changes in the expression profiles of claudins during gonocyte differentiation and in seminomas. Andrology 2015; 4:95-110. [PMID: 26588606 DOI: 10.1111/andr.12122] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2015] [Revised: 09/23/2015] [Accepted: 09/24/2015] [Indexed: 12/15/2022]
Abstract
Testicular germ cell tumors (TGCTs) are the most common type of cancer in young men and their incidence has been steadily increasing for the past decades. TGCTs and their precursor carcinoma in situ (CIS) are thought to arise from the deficient differentiation of gonocytes, precursors of spermatogonial stem cells. However, the mechanisms relating failed gonocyte differentiation to CIS formation remain unknown. The goal of this study was to uncover genes regulated during gonocyte development that would show abnormal patterns of expression in testicular tumors, as prospective links between failed gonocyte development and TGCT. To identify common gene and protein signatures between gonocytes and seminomas, we first performed gene expression analyses of transitional rat gonocytes, spermatogonia, human normal testicular, and TGCT specimens. Gene expression arrays, pathway analysis, and quantitative real-time PCR analysis identified cell adhesion molecules as a functional gene category including genes downregulated during gonocyte differentiation and highly expressed in seminomas. In particular, the mRNA and protein expressions of claudins 6 and 7 were found to decrease during gonocyte transition to spermatogonia, and to be abnormally elevated in seminomas. The dynamic changes in these genes suggest that they may play important physiological roles during gonocyte development. Moreover, our findings support the idea that TGCTs arise from a disruption of gonocyte differentiation, and position claudins as interesting genes to further study in relation to testicular cancer.
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Affiliation(s)
- G Manku
- The Research Institute of the McGill University Health Centre, McGill University, Montreal, QC, Canada.,Department of Medicine, McGill University, Montreal, QC, Canada.,Pharmacology & Therapeutics, McGill University, Montreal, QC, Canada
| | - A Hueso
- The Research Institute of the McGill University Health Centre, McGill University, Montreal, QC, Canada.,Department of Medicine, McGill University, Montreal, QC, Canada
| | - F Brimo
- The Research Institute of the McGill University Health Centre, McGill University, Montreal, QC, Canada.,Pathology, McGill University, Montreal, QC, Canada
| | - P Chan
- The Research Institute of the McGill University Health Centre, McGill University, Montreal, QC, Canada.,Surgery, McGill University, Montreal, QC, Canada
| | - P Gonzalez-Peramato
- Department of Pathology, La Paz University Hospital, Universidad Autonoma de Madrid, Madrid, Spain
| | - N Jabado
- Department of Pediatrics, McGill University, Montreal, QC, Canada
| | - T Gayden
- Department of Pediatrics, McGill University, Montreal, QC, Canada
| | - M Bourgey
- Department of Genome Quebec Innovation Centre, McGill University, Montreal, QC, Canada
| | - Y Riazalhosseini
- Department of Genome Quebec Innovation Centre, McGill University, Montreal, QC, Canada.,Department of Human Genetics, McGill University, Montreal, QC, Canada
| | - M Culty
- The Research Institute of the McGill University Health Centre, McGill University, Montreal, QC, Canada.,Department of Medicine, McGill University, Montreal, QC, Canada.,Pharmacology & Therapeutics, McGill University, Montreal, QC, Canada
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Culty M, Liu Y, Manku G, Chan WY, Papadopoulos V. Expression of steroidogenesis-related genes in murine male germ cells. Steroids 2015; 103:105-14. [PMID: 26302977 DOI: 10.1016/j.steroids.2015.08.011] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/04/2015] [Revised: 07/14/2015] [Accepted: 08/17/2015] [Indexed: 12/22/2022]
Abstract
For decades, only few tissues and cell types were defined as steroidogenic, capable of de novo steroid synthesis from cholesterol. However, with the refinement of detection methods, several tissues have now been added to the list of steroidogenic tissues. Besides their critical role as long-range acting hormones, steroids are also playing more discreet roles as local mediators and signaling molecules within the tissues they are produced. In testis, steroidogenesis is carried out by the Leydig cells through a broad network of proteins, mediating cholesterol delivery to CYP11A1, the first cytochrome of the steroidogenic cascade, and the sequential action of enzymes insuring the production of active steroids, the main one being testosterone. The knowledge that male germ cells can be directly regulated by steroids and that they express several steroidogenesis-related proteins led us to hypothesize that germ cells could produce steroids, acting as autocrine, intracrine and juxtacrine modulators, as a way to insure synchronized progression within spermatogenic cycles, and preventing inappropriate cell behaviors between neighboring cells. Gene expression and protein analyses of mouse and rat germ cells from neonatal gonocytes to spermatozoa showed that most steroidogenesis-associated genes are expressed in germ cells, showing cell type-, spermatogenic cycle-, and age-specific expression profiles. Highly expressed genes included genes involved in steroidogenesis and other cell functions, such as Acbd1 and 3, Tspo and Vdac1-3, and genes involved in fatty acids metabolism or synthesis, including Hsb17b4 10 and 12, implying broader roles than steroid synthesis in germ cells. These results support the possibility of an additional level of regulation of spermatogenesis exerted between adjacent germ cells.
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Affiliation(s)
- Martine Culty
- The Research Institute of the McGill University Health Centre, McGill University, Montreal, Quebec, Canada; Department of Medicine, McGill University, Montreal, Quebec, Canada; Department of Pharmacology & Therapeutics, McGill University, Montreal, Quebec, Canada.
| | - Ying Liu
- Section of Experimental Atherosclerosis, Center of Molecular Medicine, NHLBI, NIH, Bethesda, MD, USA
| | - Gurpreet Manku
- The Research Institute of the McGill University Health Centre, McGill University, Montreal, Quebec, Canada; Department of Medicine, McGill University, Montreal, Quebec, Canada; Department of Pharmacology & Therapeutics, McGill University, Montreal, Quebec, Canada
| | - Wai-Yee Chan
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong
| | - Vassilios Papadopoulos
- The Research Institute of the McGill University Health Centre, McGill University, Montreal, Quebec, Canada; Department of Medicine, McGill University, Montreal, Quebec, Canada; Department of Pharmacology & Therapeutics, McGill University, Montreal, Quebec, Canada
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Manku G, Culty M. Dynamic changes in the expression of apoptosis-related genes in differentiating gonocytes and in seminomas. Asian J Androl 2015; 17:403-14. [PMID: 25677133 PMCID: PMC4430938 DOI: 10.4103/1008-682x.146101] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2014] [Revised: 11/24/2014] [Accepted: 11/26/2014] [Indexed: 01/25/2023] Open
Abstract
Apoptosis is an integral part of the spermatogenic process, necessary to maintain a proper ratio of Sertoli to germ cell numbers and provide an adequate microenvironment to germ cells. Apoptosis may also represent a protective mechanism mediating the elimination of abnormal germ cells. Extensive apoptosis occurs between the first and second postnatal weeks, at the point when gonocytes, precursors of spermatogonial stem cells, should have migrated toward the basement membrane of the tubules and differentiated into spermatogonia. The mechanisms regulating this process are not well-understood. Gonocytes undergo phases of proliferation, migration, and differentiation which occur in a timely and closely regulated manner. Gonocytes failing to migrate and differentiate properly undergo apoptosis. Inadequate gonocyte differentiation has been suggested to lead to testicular germ cell tumor (TGCT) formation. Here, we examined the expression levels of apoptosis-related genes during gonocyte differentiation by quantitative real-time polymerase chain reaction, identifying 48 pro- and anti-apoptotic genes increased by at least two-fold in rat gonocytes induced to differentiate by retinoic acid, when compared to untreated gonocytes. Further analysis of the most highly expressed genes identified the pro-apoptotic genes Gadd45a and Cycs as upregulated in differentiating gonocytes and in spermatogonia compared with gonocytes. These genes were also significantly downregulated in seminomas, the most common type of TGCT, compared with normal human testicular tissues. These results indicate that apoptosis-related genes are actively regulated during gonocyte differentiation. Moreover, the down-regulation of pro-apoptotic genes in seminomas suggests that they could represent new therapeutic targets in the treatment of TGCTs.
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Affiliation(s)
- Gurpreet Manku
- The Research Institute of the McGill University Health Centre, McGill University, Montreal, Quebec, Canada
- Department of Medicine, McGill University, Montreal, Quebec, Canada
- Department of Pharmacology and Therapeutics, McGill University, Montreal, Quebec, Canada
| | - Martine Culty
- The Research Institute of the McGill University Health Centre, McGill University, Montreal, Quebec, Canada
- Department of Medicine, McGill University, Montreal, Quebec, Canada
- Department of Pharmacology and Therapeutics, McGill University, Montreal, Quebec, Canada
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Abstract
The production of spermatozoa relies on a pool of spermatogonial stem cells (SSCs), formed in infancy from the differentiation of their precursor cells, the gonocytes. Throughout adult life, SSCs will either self-renew or differentiate, in order to maintain a stem cell reserve while providing cells to the spermatogenic cycle. By contrast, gonocytes represent a transient and finite phase of development leading to the formation of SSCs or spermatogonia of the first spermatogenic wave. Gonocyte development involves phases of quiescence, cell proliferation, migration, and differentiation. Spermatogonia, on the other hand, remain located at the basement membrane of the seminiferous tubules throughout their successive phases of proliferation and differentiation. Apoptosis is an integral part of both developmental phases, allowing for the removal of defective cells and the maintenance of proper germ–Sertoli cell ratios. While gonocytes and spermatogonia mitosis are regulated by distinct factors, they both undergo differentiation in response to retinoic acid. In contrast to postpubertal spermatogenesis, the early steps of germ cell development have only recently attracted attention, unveiling genes and pathways regulating SSC self-renewal and proliferation. Yet, less is known on the mechanisms regulating differentiation. The processes leading from gonocytes to spermatogonia have been seldom investigated. While the formation of abnormal gonocytes or SSCs could lead to infertility, defective gonocyte differentiation might be at the origin of testicular germ cell tumors. Thus, it is important to better understand the molecular mechanisms regulating these processes. This review summarizes and compares the present knowledge on the mechanisms regulating mammalian gonocyte and spermatogonial differentiation.
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Manku G, Wang Y, Merkbaoui V, Boisvert A, Ye X, Blonder J, Culty M. Role of retinoic acid and platelet-derived growth factor receptor cross talk in the regulation of neonatal gonocyte and embryonal carcinoma cell differentiation. Endocrinology 2015; 156:346-59. [PMID: 25380237 PMCID: PMC5393322 DOI: 10.1210/en.2014-1524] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Neonatal gonocytes are direct precursors of spermatogonial stem cells, the cell pool that supports spermatogenesis. Although unipotent in vivo, gonocytes express pluripotency genes common with embryonic stem cells. Previously, we found that all-trans retinoic acid (RA) induced the expression of differentiation markers and a truncated form of platelet-derived growth factor receptor (PDGFR)β in rat gonocytes, as well as in F9 mouse embryonal carcinoma cells, an embryonic stem cell-surrogate that expresses somatic lineage markers in response to RA. The present study is focused on identifying the signaling pathways involved in RA-induced gonocyte and F9 cell differentiation. Mitogen-activated protein kinase kinase (MEK) 1/2 activation was required during F9 cell differentiation towards somatic lineage, whereas its inhibition potentiated RA-induced Stra8 expression, suggesting that MEK1/2 acts as a lineage specification switch in F9 cells. In both cell types, RA increased the expression of the spermatogonial/premeiotic marker Stra8, which is in line with F9 cells being at a stage before somatic-germline lineage specification. Inhibiting PDGFR kinase activity reduced RA-induced Stra8 expression. Interestingly, RA increased the expression of PDGFRα variant forms in both cell types. Together, these results suggest a potential cross talk between RA and PDGFR signaling pathways in cell differentiation. RA receptor-α inhibition partially reduced RA effects on Stra8 in gonocytes, indicating that RA acts in part via RA receptor-α. RA-induced gonocyte differentiation was significantly reduced by inhibiting SRC (v-src avian sarcoma [Schmidt-Ruppin A-2] viral oncogene) and JAK2/STAT5 (Janus kinase 2/signal transducer and activator of transcription 5) activities, implying that these signaling molecules play a role in gonocyte differentiation. These results suggest that gonocyte and F9 cell differentiation is regulated via cross talk between RA and PDGFRs using different downstream pathways.
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Affiliation(s)
- Gurpreet Manku
- The Research Institute of the McGill University Health Centre (G.M., V.M., A.B., M.C.), Montreal, Quebec, Canada H3G1A4; Departments of Pharmacology and Therapeutics (G.M., M.C.) Medicine (M.C.), McGill University, Montreal, Quebec, Canada H3G1A4; Department of Biochemistry and Molecular and Cellular Biology (Y.W.), Georgetown University Medical Center, Washington, DC 20057; and Protein Characterization Laboratory (X.Y., J.B.), Cancer Research Technology Program, Leidos Biomedical Research, Inc, Frederick National Laboratory for Cancer Research, National Cancer Institute, Frederick, Maryland 21702
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Manku G, Wing SS, Culty M. Expression of the Ubiquitin Proteasome System in Neonatal Rat Gonocytes and Spermatogonia: Role in Gonocyte Differentiation1. Biol Reprod 2012; 87:44. [DOI: 10.1095/biolreprod.112.099143] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
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Manku G, Wang Y, Thuillier R, Rhodes C, Culty M. Developmental Expression of the Translocator Protein 18 kDa (TSPO) in Testicular Germ Cells. Curr Mol Med 2012. [DOI: 10.2174/156652412800163389] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Manku G, Wang Y, Thuillier R, Rhodes C, Culty M. Developmental expression of the translocator protein 18 kDa (TSPO) in testicular germ cells. Curr Mol Med 2012; 12:467-475. [PMID: 22348614] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2011] [Revised: 01/09/2012] [Accepted: 02/02/2012] [Indexed: 05/31/2023]
Abstract
Translocator protein (TSPO) is a high affinity 18 kDa drug- and cholesterol-binding protein strongly expressed in steroidogenic tissues where it mediates cholesterol transport into mitochondria and steroid formation. Testosterone formation by Leydig cells in the testis is critical for the regulation of spermatogenesis and male fertility. Male germ cell development comprises two main phases, the pre-spermatogenesis phase occurring from fetal life to infancy and leading to spermatogonial stem cell (SSC) formation, and spermatogenesis, which consists of repetitive cycles of germ cell mitosis, meiosis and differentiation, starting with SSC differentiation and ending with spermiogenesis and spermatozoa formation. Little is known about the molecular mechanisms controlling the progression from one germ cell phenotype to the next. Here, we report that testicular germ cells express TSPO from neonatal to adult phases, although at lower levels than Leydig cells. TSPO mRNA and protein were found at specific steps of germ cell development. In fetal and neonatal gonocytes, the precursors of SSCs, TSPO appears to be mainly nuclear. In the prepubertal testis, TSPO is present in pachytene spermatocytes and dividing spermatogonia. In adult testes, it is found in a stage-dependent manner in pachytene spermatocyte and round spermatid nuclei, and in mitotic spermatogonia. In search of TSPO function, the TSPO drug ligand PK 11195 was added to isolated gonocytes with or without the proliferative factors PDGF and 17β-estradiol, and was found to have no effect on gonocyte proliferation. However, TSPO strong expression in dividing spermatogonia suggests that it might play a role in spermatogonial mitosis. Taken together, these results suggest that TSPO plays a role in specific phases of germ cell development.
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Affiliation(s)
- G Manku
- Research Institute of the McGill University Health Centre, McGill University, Montreal, Quebec, H3G 1A4, Canada
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Manku G, Wang Y, Thuillier R, Rhodes C, Culty M. Developmental Expression of the Translocator Protein 18 kDa (TSPO) in Testicular Germ Cells. Curr Mol Med 2012. [DOI: 10.2174/1566524011207040467] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Thuillier R, Mazer M, Manku G, Boisvert A, Wang Y, Culty M. Interdependence of platelet-derived growth factor and estrogen-signaling pathways in inducing neonatal rat testicular gonocytes proliferation. Biol Reprod 2010; 82:825-36. [PMID: 20089883 DOI: 10.1095/biolreprod.109.081729] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
We previously found that platelet-derived growth factor (PDGF) and 17beta-estradiol stimulate gonocyte proliferation in a dose-dependent, nonadditive manner. In the present study, we report that gonocytes express RAF1, MAP2K1, and MAPK1/3. Inhibition of RAF1 and MAP2K1/2, but not phosphoinositide-3-kinase, blocked PDGF-induced proliferation. AG-370, an inhibitor of PDGF receptor kinase activity, suppressed not only PDGF-induced proliferation but also that induced by 17beta-estradiol. In addition, RAF1 and MAP2K1/2 inhibitors blocked 17beta-estradiol-activated proliferation. The estrogen receptor antagonist ICI 182780 inhibited both the effects of 17beta-estradiol and PDGF. PDGF lost its stimulatory effect when steroid-depleted serum or no serum was used. Similarly, 17beta-estradiol did not induce gonocyte proliferation in the absence of PDGF. The xenoestrogens genistein, bisphenol A, and DES, but not coumestrol, stimulated gonocyte proliferation in a dose-dependent and PDGF-dependent manner similarly to 17beta-estradiol. Their effects were blocked by ICI 182780, suggesting that they act via the estrogen receptor. AG-370 blocked genistein and bisphenol A effects, demonstrating their requirement of PDGF receptor activation in a manner similar to 17beta-estradiol. These results demonstrate the interdependence of PDGF and estrogen pathways in stimulating in vitro gonocyte proliferation, suggesting that this critical step in gonocyte development might be regulated in vivo by the coordinated action of PDGF and estrogen. Thus, the inappropriate exposure of gonocytes to xenoestrogens might disrupt the crosstalk between the two pathways and potentially interfere with gonocyte development.
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Affiliation(s)
- Raphael Thuillier
- Department of Biochemistry and Molecular & Cellular Biology, Georgetown University Medical Center, Washington, District of Columbia, USA
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Thuillier R, Manku G, Wang Y, Culty M. Changes in MAPK pathway in neonatal and adult testis following fetal estrogen exposure and effects on rat testicular cells. Microsc Res Tech 2009; 72:773-86. [DOI: 10.1002/jemt.20756] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Manku G. Spectrophotometric determination of osmium(IV), iridium(IV) and platinum(iv) and separation and determination of palladium(II) and ruthenium(III) in the presence of other platinum metals, with oximidobenzotetronic acid as reagent. Talanta 1969; 16:1421-9. [DOI: 10.1016/0039-9140(69)80183-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/1968] [Revised: 10/15/1968] [Accepted: 11/03/1968] [Indexed: 10/18/2022]
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Manku G. Rapid spectrophotometric determination of cobalt after extraction using oximidobenzotetronic acid. Talanta 1969; 16:1431-4. [DOI: 10.1016/0039-9140(69)80184-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/1969] [Accepted: 04/01/1969] [Indexed: 11/30/2022]
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