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Le Beulze M, Daubech C, Balde-Camara A, Ghieh F, Vialard F. Mammal Reproductive Homeobox (Rhox) Genes: An Update of Their Involvement in Reproduction and Development. Genes (Basel) 2023; 14:1685. [PMID: 37761825 PMCID: PMC10531175 DOI: 10.3390/genes14091685] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Revised: 08/16/2023] [Accepted: 08/23/2023] [Indexed: 09/29/2023] Open
Abstract
The reproductive homeobox on the X chromosome (RHOX) genes were first identified in the mouse during the 1990s and have a crucial role in reproduction. In various transcription factors with a key regulatory role, the homeobox sequence encodes a "homeodomain" DNA-binding motif. In the mouse, there are three clusters of Rhox genes (α, β, and γ) on the X chromosome. Each cluster shows temporal and/or quantitative collinearity, which regulates the progression of the embryonic development process. Although the RHOX family is conserved in mammals, the interspecies differences in the number of RHOX genes and pseudogenes testifies to a rich evolutionary history with several relatively recent events. In the mouse, Rhox genes are mainly expressed in reproductive tissues, and several have a role in the differentiation of primordial germ cells (Rhox1, Rhox6, and Rhox10) and in spermatogenesis (Rhox1, Rhox8, and Rhox13). Despite the lack of detailed data on human RHOX, these genes appear to be involved in the formation of germ cells because they are predominantly expressed during the early (RHOXF1) and late (RHOXF2/F2B) stages of germ cell development. Furthermore, the few variants identified to date are thought to induce or predispose to impaired spermatogenesis and severe oligozoospermia or azoospermia. In the future, research on the pathophysiology of the human RHOX genes is likely to confirm the essential role of this family in the reproductive process and might help us to better understand the various causes of infertility and characterize the associated human phenotypes.
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Affiliation(s)
- Morgane Le Beulze
- Equipe RHuMA, UMR-BREED, UFR Simone Veil Santé, F-78180 Montigny-le-Bretonneux, France; (M.L.B.); (C.D.); (A.B.-C.); (F.G.)
- UFR des Sciences de la Santé Simone Veil, Université de Versailles-Saint Quentin en Yvelines—Université Paris Saclay (UVSQ), INRAE, BREED, F-78350 Jouy-en-Josas, France
| | - Cécile Daubech
- Equipe RHuMA, UMR-BREED, UFR Simone Veil Santé, F-78180 Montigny-le-Bretonneux, France; (M.L.B.); (C.D.); (A.B.-C.); (F.G.)
- UFR des Sciences de la Santé Simone Veil, Université de Versailles-Saint Quentin en Yvelines—Université Paris Saclay (UVSQ), INRAE, BREED, F-78350 Jouy-en-Josas, France
| | - Aissatu Balde-Camara
- Equipe RHuMA, UMR-BREED, UFR Simone Veil Santé, F-78180 Montigny-le-Bretonneux, France; (M.L.B.); (C.D.); (A.B.-C.); (F.G.)
- UFR des Sciences de la Santé Simone Veil, Université de Versailles-Saint Quentin en Yvelines—Université Paris Saclay (UVSQ), INRAE, BREED, F-78350 Jouy-en-Josas, France
| | - Farah Ghieh
- Equipe RHuMA, UMR-BREED, UFR Simone Veil Santé, F-78180 Montigny-le-Bretonneux, France; (M.L.B.); (C.D.); (A.B.-C.); (F.G.)
- UFR des Sciences de la Santé Simone Veil, Université de Versailles-Saint Quentin en Yvelines—Université Paris Saclay (UVSQ), INRAE, BREED, F-78350 Jouy-en-Josas, France
| | - François Vialard
- Equipe RHuMA, UMR-BREED, UFR Simone Veil Santé, F-78180 Montigny-le-Bretonneux, France; (M.L.B.); (C.D.); (A.B.-C.); (F.G.)
- UFR des Sciences de la Santé Simone Veil, Université de Versailles-Saint Quentin en Yvelines—Université Paris Saclay (UVSQ), INRAE, BREED, F-78350 Jouy-en-Josas, France
- Département de Génétique, CHI de Poissy St. Germain en Laye, F-78300 Poissy, France
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Tan K, Wilkinson MF. Developmental regulators moonlighting as transposons defense factors. Andrology 2023; 11:891-903. [PMID: 36895139 PMCID: PMC11162177 DOI: 10.1111/andr.13427] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Revised: 02/17/2023] [Accepted: 03/04/2023] [Indexed: 03/11/2023]
Abstract
BACKGROUND The germline perpetuates genetic information across generations. To maintain the integrity of the germline, transposable elements in the genome must be silenced, as these mobile elements would otherwise engender widespread mutations passed on to subsequent generations. There are several well-established mechanisms that are dedicated to providing defense against transposable elements, including DNA methylation, RNA interference, and the PIWI-interacting RNA pathway. OBJECTIVES Recently, several studies have provided evidence that transposon defense is not only provided by factors dedicated to this purpose but also factors with other roles, including in germline development. Many of these are transcription factors. Our objective is to summarize what is known about these "bi-functional" transcriptional regulators. MATERIALS AND METHODS Literature search. RESULTS AND CONCLUSION We summarize the evidence that six transcriptional regulators-GLIS3, MYBL1, RB1, RHOX10, SETDB1, and ZBTB16-are both developmental regulators and transposable element-defense factors. These factors act at different stages of germ cell development, including in pro-spermatogonia, spermatogonial stem cells, and spermatocytes. Collectively, the data suggest a model in which specific key transcriptional regulators have acquired multiple functions over evolutionary time to influence developmental decisions and safeguard transgenerational genetic information. It remains to be determined whether their developmental roles were primordial and their transposon defense roles were co-opted, or vice versa.
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Affiliation(s)
- Kun Tan
- Department of Obstetrics, Gynecology, and Reproductive Sciences, University of California San Diego, La Jolla, California, USA
| | - Miles F. Wilkinson
- Department of Obstetrics, Gynecology, and Reproductive Sciences, University of California San Diego, La Jolla, California, USA
- Institute of Genomic Medicine, University of California San Diego, La Jolla, California, USA
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Bhardwaj A, Sohni A, Lou CH, De Gendt K, Zhang F, Kim E, Subbarayalu P, Chan W, Kerkhofs S, Claessens F, Kimmins S, Rao MK, Meistrich M, Wilkinson MF. Concordant Androgen-Regulated Expression of Divergent Rhox5 Promoters in Sertoli Cells. Endocrinology 2022; 163:6432187. [PMID: 34902009 PMCID: PMC8667857 DOI: 10.1210/endocr/bqab237] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/10/2021] [Indexed: 11/19/2022]
Abstract
Concordant transcriptional regulation can generate multiple gene products that collaborate to achieve a common goal. Here we report a case of concordant transcriptional regulation that instead drives a single protein to be produced in the same cell type from divergent promoters. This gene product-the RHOX5 homeobox transcription factor-is translated from 2 different mRNAs with different 5' untranslated regions (UTRs) transcribed from alternative promoters. Despite the fact that these 2 promoters-the proximal promoter (Pp) and the distal promoter (Pd)-exhibit different patterns of tissue-specific activity, share no obvious sequence identity, and depend on distinct transcription factors for expression, they exhibit a remarkably similar expression pattern in the testes. In particular, both depend on androgen signaling for expression in the testes, where they are specifically expressed in Sertoli cells and have a similar stage-specific expression pattern during the seminiferous epithelial cycle. We report evidence for 3 mechanisms that collaborate to drive concordant Pp/Pd expression. First, both promoters have an intrinsic ability to respond to androgen receptor and androgen. Second, the Pp acts as an enhancer to promote androgen-dependent transcription from the Pd. Third, Pd transcription is positively autoregulated by the RHOX5 protein, which is first produced developmentally from the Pp. Together, our data support a model in which the Rhox5 homeobox gene evolved multiple mechanisms to activate both of its promoters in Sertoli cells to produce Rhox5 in an androgen-dependent manner during different phases of spermatogenesis.
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Affiliation(s)
- Anjana Bhardwaj
- Department of Biochemistry and Molecular Biology, The University of Texas M.D. Anderson Cancer Center, Houston, TX 77030, USA
- Department of Breast Surgical Oncology, The University of Texas M.D. Anderson Cancer Center, Houston, Texas 77030, USA
| | - Abhishek Sohni
- School of Medicine, Department of Obstetrics, Gynecology and Reproductive Sciences, University of California, San Diego, La Jolla, CA 92093-0695, USA
| | - Chih-Hong Lou
- School of Medicine, Department of Obstetrics, Gynecology and Reproductive Sciences, University of California, San Diego, La Jolla, CA 92093-0695, USA
| | - Karel De Gendt
- School of Medicine, Department of Obstetrics, Gynecology and Reproductive Sciences, University of California, San Diego, La Jolla, CA 92093-0695, USA
- KU Leuven, Campus Gasthuisberg, O/N1, BE-3000 Leuven, Belgium
| | - Fanmao Zhang
- Department of Biochemistry and Molecular Biology, The University of Texas M.D. Anderson Cancer Center, Houston, TX 77030, USA
| | - Eunah Kim
- Department of Biochemistry and Molecular Biology, The University of Texas M.D. Anderson Cancer Center, Houston, TX 77030, USA
- Department of Environmental Health and Safety, University of Texas Health Sciences Center, Houston, TX, USA
| | - Panneerdoss Subbarayalu
- Department of Cell Systems and Anatomy, University of Texas HealthSan Antonio, San Antonio, TX 78229, USA
| | - Waikin Chan
- Department of Biochemistry and Molecular Biology, The University of Texas M.D. Anderson Cancer Center, Houston, TX 77030, USA
| | | | - Frank Claessens
- KU Leuven, Campus Gasthuisberg, O/N1, BE-3000 Leuven, Belgium
| | - Sarah Kimmins
- Department of Animal Sciences, McGill UniversityMontreal, Quebec H3A 0G4, Canada
| | - Manjeet K Rao
- Department of Cell Systems and Anatomy, University of Texas HealthSan Antonio, San Antonio, TX 78229, USA
| | - Marvin Meistrich
- Department of Experimental Radiation Oncology, The University of Texas M.D. Anderson Cancer Center, Houston, TX 77030, USA
| | - Miles F Wilkinson
- School of Medicine, Department of Obstetrics, Gynecology and Reproductive Sciences, University of California, San Diego, La Jolla, CA 92093-0695, USA
- Institute of Genomic Medicine, University of California, San Diego, La Jolla, CA 92093, USA
- Correspondence: M. F. Wilkinson, PhD, University of California San Diego, San Diego, 9500 Gilman Drive # 0695, La Jolla, CA 92093-0695, USA. . Previous Affiliation: Miles F. Wilkinson’s previous affiliation is Department of Biochemistry and Molecular Biology, The University of Texas M.D. Anderson Cancer Center, Houston, TX 77030, USA
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Przygrodzka E, Plewes MR, Davis JS. Luteinizing Hormone Regulation of Inter-Organelle Communication and Fate of the Corpus Luteum. Int J Mol Sci 2021; 22:9972. [PMID: 34576135 PMCID: PMC8470545 DOI: 10.3390/ijms22189972] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2021] [Revised: 09/10/2021] [Accepted: 09/12/2021] [Indexed: 12/18/2022] Open
Abstract
The corpus luteum is an endocrine gland that synthesizes the steroid hormone progesterone. luteinizing hormone (LH) is a key luteotropic hormone that stimulates ovulation, luteal development, progesterone biosynthesis, and maintenance of the corpus luteum. Luteotropic and luteolytic factors precisely regulate luteal structure and function; yet, despite recent scientific progress within the past few years, the exact mechanisms remain largely unknown. In the present review, we summarize the recent progress towards understanding cellular changes induced by LH in steroidogenic luteal cells. Herein, we will focus on the effects of LH on inter-organelle communication and steroid biosynthesis, and how LH regulates key protein kinases (i.e., AMPK and MTOR) responsible for controlling steroidogenesis and autophagy in luteal cells.
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Affiliation(s)
- Emilia Przygrodzka
- Olson Center for Women’s Health, Department of Obstetrics and Gynecology, University of Nebraska Medical Center, Nebraska Medical Center, Omaha, NE 68198-3255, USA; (E.P.); (M.R.P.)
| | - Michele R. Plewes
- Olson Center for Women’s Health, Department of Obstetrics and Gynecology, University of Nebraska Medical Center, Nebraska Medical Center, Omaha, NE 68198-3255, USA; (E.P.); (M.R.P.)
- Veterans Affairs Nebraska Western Iowa Health Care System, 4101 Woolworth Ave, Omaha, NE 68105, USA
| | - John S. Davis
- Olson Center for Women’s Health, Department of Obstetrics and Gynecology, University of Nebraska Medical Center, Nebraska Medical Center, Omaha, NE 68198-3255, USA; (E.P.); (M.R.P.)
- Veterans Affairs Nebraska Western Iowa Health Care System, 4101 Woolworth Ave, Omaha, NE 68105, USA
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Vellingiri B, Iyer M, Devi Subramaniam M, Jayaramayya K, Siama Z, Giridharan B, Narayanasamy A, Abdal Dayem A, Cho SG. Understanding the Role of the Transcription Factor Sp1 in Ovarian Cancer: from Theory to Practice. Int J Mol Sci 2020; 21:E1153. [PMID: 32050495 PMCID: PMC7038193 DOI: 10.3390/ijms21031153] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Revised: 02/01/2020] [Accepted: 02/04/2020] [Indexed: 12/23/2022] Open
Abstract
Ovarian cancer (OC) is one of the deadliest cancers among women contributing to high risk of mortality, mainly owing to delayed detection. There is no specific biomarker for its detection in early stages. However, recent findings show that over-expression of specificity protein 1 (Sp1) is involved in many OC cases. The ubiquitous transcription of Sp1 apparently mediates the maintenance of normal and cancerous biological processes such as cell growth, differentiation, angiogenesis, apoptosis, cellular reprogramming and tumorigenesis. Sp1 exerts its effects on cellular genes containing putative GC-rich Sp1-binding site in their promoters. A better understanding of the mechanisms underlying Sp1 transcription factor (TF) regulation and functions in OC tumorigenesis could help identify novel prognostic markers, to target cancer stem cells (CSCs) by following cellular reprogramming and enable the development of novel therapies for future generations. In this review, we address the structure, function, and biology of Sp1 in normal and cancer cells, underpinning the involvement of Sp1 in OC tumorigenesis. In addition, we have highlighted the influence of Sp1 TF in cellular reprogramming of iPSCs and how it plays a role in controlling CSCs. This review highlights the drugs targeting Sp1 and their action on cancer cells. In conclusion, we predict that research in this direction will be highly beneficial for OC treatment, and chemotherapeutic drugs targeting Sp1 will emerge as a promising therapy for OC.
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Affiliation(s)
- Balachandar Vellingiri
- Human Molecular Cytogenetics and Stem Cell Laboratory, Department of Human Genetics and Molecular Biology, Bharathiar University, Coimbatore 641046, India
| | - Mahalaxmi Iyer
- Department of Zoology, Avinashilingam Institute for Home Science and Higher Education for Women, Coimbatore 641043, India; (M.I.); (K.J.)
| | - Mohana Devi Subramaniam
- Department of Genetics and Molecular Biology, Vision Research Foundation, Sankara Nethralaya, Chennai 600006, India;
| | - Kaavya Jayaramayya
- Department of Zoology, Avinashilingam Institute for Home Science and Higher Education for Women, Coimbatore 641043, India; (M.I.); (K.J.)
| | - Zothan Siama
- Department of Zoology, School of Life-science, Mizoram University, Aizawl 796004, Mizoram, India;
| | - Bupesh Giridharan
- R&D Wing, Sree Balaji Medical College and Hospital (SBMCH), BIHER, Chromepet, Chennai 600044, Tamil Nadu, India;
| | - Arul Narayanasamy
- Disease Proteomics Laboratory, Department of Zoology, Bharathiar University, Coimbatore 641046, Tamil Nadu, India;
| | - Ahmed Abdal Dayem
- Molecular & Cellular Reprogramming Center, Department of Stem Cell & Regenerative Biotechnology, Konkuk University, Seoul 05029, Korea;
| | - Ssang-Goo Cho
- Molecular & Cellular Reprogramming Center, Department of Stem Cell & Regenerative Biotechnology, Konkuk University, Seoul 05029, Korea;
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Welborn JP, Davis MG, Ebers SD, Stodden GR, Hayashi K, Cheatwood JL, Rao MK, MacLean JA. Rhox8 Ablation in the Sertoli Cells Using a Tissue-Specific RNAi Approach Results in Impaired Male Fertility in Mice. Biol Reprod 2015; 93:8. [PMID: 25972016 DOI: 10.1095/biolreprod.114.124834] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2014] [Accepted: 05/11/2015] [Indexed: 12/27/2022] Open
Abstract
The reproductive homeobox X-linked, Rhox, genes encode transcription factors that are selectively expressed in reproductive tissues. While there are 33 Rhox genes in mice, only Rhox and Rhox8 are expressed in Sertoli cells, suggesting that they may regulate the expression of somatic-cell gene products crucial for germ cell development. We previously characterized Rhox5-null mice, which are subfertile, exhibiting excessive germ cell apoptosis and compromised sperm motility. To assess the role of Rhox8 in Sertoli cells, we used a tissue-specific RNAi approach to knockdown RHOX8 in vivo, in which the Rhox5 promoter was used to drive Rhox8-siRNA transgene expression in the postnatal Sertoli cells. Western and immunohistochemical analysis confirmed Sertoli-specific knockdown of RHOX8. However, other Sertoli markers, Gata1 and Rhox5, maintained normal expression patterns, suggesting that the knockdown was specific. Interestingly, male RHOX8-knockdown animals showed significantly reduced spermatogenic output, increased germ cell apoptosis, and compromised sperm motility, leading to impaired fertility. Importantly, our results revealed that while some RHOX5-dependent factors were also misregulated in Sertoli cells of RHOX8-knockdown animals, the majority were not, and novel putative RHOX8-regulated genes were identified. This suggests that while reduction in levels of RHOX5 and RHOX8 in Sertoli cells elicits similar phenotypes, these genes are not entirely redundant. Taken together, our study underscores the importance of Rhox genes in male fertility and suggests that Sertoli cell-specific expression of Rhox5 and Rhox8 is critical for complete male fertility.
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Affiliation(s)
- Joshua P Welborn
- Department of Physiology, Southern Illinois University School of Medicine, Carbondale, Illinois
| | - Matthew G Davis
- Department of Physiology, Southern Illinois University School of Medicine, Carbondale, Illinois
| | - Steven D Ebers
- Department of Physiology, Southern Illinois University School of Medicine, Carbondale, Illinois
| | - Genna R Stodden
- Department of Physiology, Southern Illinois University School of Medicine, Carbondale, Illinois
| | - Kanako Hayashi
- Department of Physiology, Southern Illinois University School of Medicine, Carbondale, Illinois
| | - Joseph L Cheatwood
- Department of Anatomy, Southern Illinois University School of Medicine, Carbondale, Illinois
| | - Manjeet K Rao
- Department of Cellular and Structural Biology, Greehey Children's Cancer Research Institute, University of Texas Health Science Center at San Antonio, San Antonio, Texas
| | - James A MacLean
- Department of Physiology, Southern Illinois University School of Medicine, Carbondale, Illinois
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Pan B, Toms D, Shen W, Li J. MicroRNA-378 regulates oocyte maturation via the suppression of aromatase in porcine cumulus cells. Am J Physiol Endocrinol Metab 2015; 308:E525-34. [PMID: 25628423 PMCID: PMC4360015 DOI: 10.1152/ajpendo.00480.2014] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
We sought to investigate whether miR-378 plays a role in cumulus cells and whether the manipulation of miRNA levels in cumulus cells influences oocyte maturation in vitro. Cumulus-oocyte complexes (COCs) from ovarian follicles had significantly lower levels of precursor and mature miR-378 in cumulus cells surrounding metaphase II (MII) oocytes than cumulus cells surrounding germinal vesicle (GV) oocytes, suggesting a possible role of miR-378 during COC maturation. Overexpression of miR-378 in cumulus cells impaired expansion and decreased expression of genes associated with expansion (HAS2, PTGS2) and oocyte maturation (CX43, ADAMTS1, PGR). Cumulus cell expression of miR-378 also suppressed oocyte progression from the GV to MII stage (from 54 ± 2.7 to 31 ± 5.1%), accompanied by a decrease of growth differentiation factor 9 (GDF9), bone morphogenetic protein 15 (BMP15), zona pellucida 3 (ZP3), and CX37 in the oocytes. Subsequent in vitro fertilization resulted in fewer oocytes from COCs overexpressing miR-378 reaching the blastocyst stage (7.3 ± 0.7 vs. 16.6 ± 0.5%). miR-378 knockdown led to increased cumulus expansion and oocyte progression to MII, confirming a specific effect of miR-378 in suppressing COC maturation. Aromatase (CYP19A1) expression in cumulus cells was also inhibited by miR-378, leading to a significant decrease in estradiol production. The addition of estradiol to IVM culture medium reversed the effect of miR-378 on cumulus expansion and oocyte meiotic progression, suggesting that decreased estradiol production via suppression of aromatase may be one of the mechanisms by which miR-378 regulates the maturation of COCs. Our data suggest that miR-378 alters gene expression and function in cumulus cells and influences oocyte maturation, possibly via oocyte-cumulus interaction and paracrine regulation.
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Affiliation(s)
- Bo Pan
- Department of Animal and Poultry Science, University of Guelph, Guelph, Ontario, Canada; and
| | - Derek Toms
- Department of Animal and Poultry Science, University of Guelph, Guelph, Ontario, Canada; and
| | - Wei Shen
- Laboratory of Germ Cell Biology, College of Animal Science and Technology, Qingdao Agricultural University, Qingdao, China
| | - Julang Li
- Department of Animal and Poultry Science, University of Guelph, Guelph, Ontario, Canada; and
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MacLean JA, Hu Z, Welborn JP, Song HW, Rao MK, Wayne CM, Wilkinson MF. The RHOX homeodomain proteins regulate the expression of insulin and other metabolic regulators in the testis. J Biol Chem 2013; 288:34809-25. [PMID: 24121513 DOI: 10.1074/jbc.m113.486340] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Defects in cellular metabolism have been widely implicated in causing male infertility, but there has been little progress in understanding the underlying mechanism. Here we report that several key metabolism genes are regulated in the testis by Rhox5, the founding member of a large X-linked homeobox gene cluster. Among these Rhox5-regulated genes are insulin 2 (Ins2), resistin (Retn), and adiponectin (Adipoq), all of which encode secreted proteins that have profound and wide-ranging effects on cellular metabolism. The ability of Rhox5 to regulate their levels in the testis has the potential to dictate metabolism locally in this organ, given the existence of the blood-testes barrier. We demonstrate that Ins2 is a direct target of Rhox5 in Sertoli cells, and we show that this regulation is physiologically significant, because Rhox5-null mice fail to up-regulate Ins2 expression during the first wave of spermatogenesis and have insulin-signaling defects. We identify other Rhox family members that induce Ins2 transcription, define protein domains and homeodomain amino acid residues crucial for this property, and demonstrate that this regulation is conserved. Rhox5-null mice also exhibit altered expression of other metabolism genes, including those encoding the master transcriptional regulators of metabolism, PPARG and PPARGC1A, as well as SCD1, the rate-limiting enzyme for fatty acid metabolism. These results, coupled with the known roles of RHOX5 and its target metabolism genes in spermatogenesis in vivo, lead us to propose a model in which RHOX5 is a central transcription factor that promotes the survival of male germ cells via its effects on cellular metabolism.
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Affiliation(s)
- James A MacLean
- From the Department of Physiology, Southern Illinois University School of Medicine, Carbondale, Illinois 62901
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Lee SE, Lee SY, Lee KA. Rhox in mammalian reproduction and development. Clin Exp Reprod Med 2013; 40:107-14. [PMID: 24179867 PMCID: PMC3811726 DOI: 10.5653/cerm.2013.40.3.107] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2013] [Revised: 09/10/2013] [Accepted: 09/10/2013] [Indexed: 01/06/2023] Open
Abstract
Homeobox genes play essential roles in embryonic development and reproduction. Recently, a large cluster of homeobox genes, reproductive homeobox genes on the X chromosome (Rhox) genes, was discovered as three gene clusters, α, β, and γ in mice. It was found that Rhox genes were selectively expressed in reproduction-associated tissues, such as those of the testes, epididymis, ovaries, and placenta. Hence, it was proposed that Rhox genes are important for regulating various reproductive features, especially gametogenesis in male as well as in female mammals. It was first determined that 12 Rhox genes are clustered into α (Rhox1-4), β (Rhox5-9), and γ (Rhox10-12) subclusters, and recently Rhox13 has also been found. At present, 33 Rhox genes have been identified in the mouse genome, 11 in the rat, and three in the human. Rhox genes are also responsible for embryonic development, with considerable amounts of Rhox expression in trophoblasts, placenta tissue, embryonic stem cells, and primordial germ cells. In this article we summarized the current understanding of Rhox family genes involved in reproduction and embryonic development and elucidated a previously unreported cell-specific expression in ovarian cells.
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Affiliation(s)
- Sang-Eun Lee
- Department of Biomedical Science, College of Life Science, CHA University, Seoul, Korea
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10
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Brown RM, Davis MG, Hayashi K, MacLean JA. Regulated expression of Rhox8 in the mouse ovary: evidence for the role of progesterone and RHOX5 in granulosa cells. Biol Reprod 2013; 88:126. [PMID: 23536368 DOI: 10.1095/biolreprod.112.103267] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
The gonadotropin surge is the essential trigger to stimulate ovulation and luteinization of ovarian follicles. While the hormone signals from the brain that initiate ovulation are known, the specific targets which regulate this process are not well known. In this study, we assessed the suitability of the Rhox homeobox gene cluster to serve as the master regulators of folliculogenesis. In superovulated (equine chorionic gonadotropin [eCG]/human chorionic gonadotropin [hCG]) mice, the Rhox genes exhibited four distinct windows of peak expression, suggesting that these genes may regulate specific events during the ovulatory cycle. Like many members of the cluster, Rhox8 mRNA and protein were induced by follicle stimulating hormone [FSH]/eCG in granulosa cells. However, Rhox8 displayed unique peak expression at 8 h post-hCG administration, implying it might be the lone member of the cluster regulated by progesterone. Subsequent promoter analysis in granulosa cells revealed relevant homeobox binding and progesterone response elements within Rhox8's 5'-flanking region. In superovulated mice, progesterone receptor (PGR) is recruited to the Rhox8 promoter, as assessed by chromatin immunoprecipitation. In Rhox5-null mice, Rhox8 mRNA was reduced at 2 h and 4 h post-hCG administration but recovered once the follicles passed the antral stage of development. Conversely, in progesterone receptor knockout mice, Rhox8 exhibited normal stimulation by eCG but failed to reach its peak mRNA level at 8 h post-hCG found in wild-type mice. This suggests a model in which Rhox8 transcription is dependent upon RHOX5 during early folliculogenesis and upon progesterone during the periovulatory window when RHOX5 normally wanes. In support of this model, transfection of RHOX5 and PGR expression plasmids stimulated, whereas dominant negative and mutant constructs inhibited, Rhox8 promoter activity.
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Affiliation(s)
- Raquel M Brown
- Department of Physiology, Southern Illinois University School of Medicine, Carbondale, IL 62901, USA
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Kawabe S, Yazawa T, Kanno M, Usami Y, Mizutani T, Imamichi Y, Ju Y, Matsumura T, Orisaka M, Miyamoto K. A novel isoform of liver receptor homolog-1 is regulated by steroidogenic factor-1 and the specificity protein family in ovarian granulosa cells. Endocrinology 2013; 154:1648-60. [PMID: 23471216 DOI: 10.1210/en.2012-2008] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Liver receptor homolog-1 (LRH-1) is a member of the nuclear receptor 5A (NR5A) subfamily. It is expressed in granulosa cells of the ovary and is involved in steroidogenesis and ovulation. To reveal the transcriptional regulatory mechanism of LRH-1, we determined its transcription start site in the ovary using KGN cells, a human granulosa cell tumor cell line. 5'-rapid amplification of cDNA ends PCR revealed that human ovarian LRH-1 was transcribed from a novel transcription start site, termed exon 2o, located 41 bp upstream of the reported exon 2. The novel LRH-1 isoform was expressed in the human ovary but not the liver. Promoter analysis and an EMSA indicated that a steroidogenic factor-1 (SF-1) binding site and a GC box upstream of exon 2o were required for promoter activity, and that SF-1 and specificity protein (Sp)-1/3 bind to the respective regions in ovarian granulosa cells. In KGN cells, transfection of SF-1 increased ovarian LRH-1 promoter activity and SF-1-dependent reporter activity was further enhanced when peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) was cotransfected. In Drosophila SL2 cells, Sp1 was more effective than Sp3 in enhancing promoter activity, and co-transfection of the NR5A-family synergistically increased activity. Infection with adenoviruses expressing SF-1 or PGC-1α induced LRH-1 expression in KGN cells. These results indicate that the expression of human LRH-1 is regulated in a tissue-specific manner, and that the novel promoter region is controlled by the Sp-family, NR5A-family and PGC-1α in ovarian granulosa cells in a coordinated fashion.
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Affiliation(s)
- Shinya Kawabe
- Department of Biochemistry, University of Fukui, Fukui 910-1193, Japan
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12
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Li Q, O'Malley ME, Bartlett DL, Guo ZS. Homeobox gene Rhox5 is regulated by epigenetic mechanisms in cancer and stem cells and promotes cancer growth. Mol Cancer 2011; 10:63. [PMID: 21609483 PMCID: PMC3125390 DOI: 10.1186/1476-4598-10-63] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2010] [Accepted: 05/24/2011] [Indexed: 12/29/2022] Open
Abstract
Background Homeobox genes murine Rhox5 and human RHOXF1 are expressed in early embryonic stages and then mostly restricted to germline tissues in normal adult, yet they are aberrantly expressed in cancer cells in vitro and in vivo . Here we study the epigenetic regulation and potential functions of Rhox5 gene. Findings In Rhox5 -silenced or extremely low expresser cells, we observed low levels of active histone epigenetic marks (H3ac, H4ac and H3K4me2) and high levels of repressive mark H3K9me2 along with DNA hypermethylation in the promoter. In Rhox5 low expresser cells, we typically observed modest levels of both active and repressive histone marks along with moderate DNA methylation. In Rhox5 highly expressed CT26 cancer cells, we observed DNA hypomethylation along with high levels of both active and repressive histone marks. Epigenetic drugs (retinoic acid and MS-275) induced F9 cell differentiation with enhanced Rhox5 expression and dynamic changes of epigenetic marks. Finally, Rhox5 knockdown by small hairpin RNA (shRNA) in CT26 colon cancer decreased cell proliferation and migration in vitro and tumor growth in vivo . Conclusions Both DNA methylation and histone methylation/acetylation play key roles in modulating Rhox5 expression in various cell types. The stem cell-like "bivalent domain", an epigenetic feature originally identified in key differentiation genes within stem cells, exists in the Rhox5 gene promoter in not only embryonic stem cells but also cancer cells, cancer stem cells, and differentiated Sertoli cells. As Ras signaling-dependent Rhox5 expression promotes tumor growth, Rhox5 may be an ideal target for therapeutic intervention in cancer.
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Affiliation(s)
- Qiang Li
- The University of Pittsburgh Cancer Institute, University of Pittsburgh, Pennsylvania 15213, USA
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13
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The rhox homeobox gene cluster is imprinted and selectively targeted for regulation by histone h1 and DNA methylation. Mol Cell Biol 2011; 31:1275-87. [PMID: 21245380 DOI: 10.1128/mcb.00734-10] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Histone H1 is an abundant and essential component of chromatin whose precise role in regulating gene expression is poorly understood. Here, we report that a major target of H1-mediated regulation in embryonic stem (ES) cells is the X-linked Rhox homeobox gene cluster. To address the underlying mechanism, we examined the founding member of the Rhox gene cluster-Rhox5-and found that its distal promoter (Pd) loses H1, undergoes demethylation, and is transcriptionally activated in response to loss of H1 genes in ES cells. Demethylation of the Pd is required for its transcriptional induction and we identified a single cytosine in the Pd that, when methylated, is sufficient to inhibit Pd transcription. Methylation of this single cytosine prevents the Pd from binding GA-binding protein (GABP), a transcription factor essential for Pd transcription. Thus, H1 silences Rhox5 transcription by promoting methylation of one of its promoters, a mechanism likely to extend to other H1-regulated Rhox genes, based on analysis of ES cells lacking DNA methyltransferases. The Rhox cluster genes targeted for H1-mediated transcriptional repression are also subject to another DNA methylation-regulated process: Xp imprinting. Remarkably, we found that only H1-regulated Rhox genes are imprinted, not those immune to H1-mediated repression. Together, our results indicate that the Rhox gene cluster is a major target of H1-mediated transcriptional repression in ES cells and that H1 is a candidate to have a role in Xp imprinting.
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14
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Hamel M, Dufort I, Robert C, Léveillé MC, Leader A, Sirard MA. Identification of follicular marker genes as pregnancy predictors for human IVF: new evidence for the involvement of luteinization process. Mol Hum Reprod 2010; 16:548-56. [PMID: 20610614 DOI: 10.1093/molehr/gaq051] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Multiple pregnancy represents an important health risk to both mother and child in fertility treatment. To reduce a high twin rate, restriction to one embryo transfer is needed. Morphological evaluation methods for predicting embryo viability has significant limitations. Tight communication exists between the follicular cells (FCs) and the oocyte; therefore, developmental competence may be determined by markers expressed in the surrounding FCs. In this study, cells were recovered on a per-follicle basis by individual follicle puncture. Hybridization analysis using a custom-made complementary DNA microarray containing FC transcripts was performed. Genes expressed in FCs associated with good morphological transferred embryos were identified from follicles associated with a pregnancy outcome (pregnancy group) or no pregnancy (non-pregnancy group). Ten candidates from the Pregnancy group and three from the Non-pregnancy group were validated by quantitative RT-PCR. The best predictors associated with pregnancy were UDP-glucose pyrophosphorylase-2 and pleckstrin homology-like domain, family A, member 1. Genes assessment showed no significant candidate genes associated with non-pregnancy outcome, but GA-binding protein transcription factor beta1 showed a tendency to be potentially more expressed in the non-pregnancy group. These markers could be related to granulosa luteinization process and could be used to improve embryo selection for successful single embryo transfer.
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Affiliation(s)
- Mélanie Hamel
- Département des Sciences Animales, Centre de Recherche en Biologie de la Reproduction (CRBR), Université Laval, Montréal, QC, Canada
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15
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Abstract
Homeobox genes encode transcription factors that have crucial roles in embryogenesis. A recently discovered set of homeobox genes--the Rhox genes--are expressed during both embryogenesis and in adult reproductive tissues. The 33 known mouse Rhox genes are clustered together in a single region on the X chromosome, while likely descendents of the primodial Rhox cluster, Arx and Esx1, have moved to other positions on the X chromosome. Here, we summarize what is known about the regulation and function of Rhox cluster and Rhox-related genes during embryogenesis and gametogenesis. The founding member of the Rhox gene cluster--Rhox5 (previously known as Pem)--has been studied in the most depth and thus is the focus of this review. We also discuss the unusually rapid evolution of the Rhox gene cluster.
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Affiliation(s)
- James A MacLean
- Department of Physiology, School of Medicine, Southern Illinois University, Carbondale, IL 62901, USA
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16
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Escudero JM, Haller JL, Clay CM, Escudero KW. Microarray analysis of Foxl2 mediated gene regulation in the mouse ovary derived KK1 granulosa cell line: Over-expression of Foxl2 leads to activation of the gonadotropin releasing hormone receptor gene promoter. J Ovarian Res 2010; 3:4. [PMID: 20167115 PMCID: PMC2831895 DOI: 10.1186/1757-2215-3-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2009] [Accepted: 02/18/2010] [Indexed: 01/12/2023] Open
Abstract
BACKGROUND The Foxl2 transcription factor is required for ovarian function during follicular development. The mechanism of Foxl2 regulation of this process has not been elucidated. Our approach to begin to understand Foxl2 function is through the identification of Foxl2 regulated genes in the ovary. METHODS Transiently transfected KK1 mouse granulosa cells were used to identify genes that are potentially regulated by Foxl2. KK1 cells were transfected in three groups (mock, activated, and repressed) and twenty-four hours later RNA was isolated and submitted for Affymetrix microarray analysis. Genesifter software was used to carry out analysis of microarray data. One identified target, the gonadotropin releasing hormone receptor (GnRHR) gene, was chosen for further study and validation of Foxl2 responsiveness. Transient transfection analyses were carried out to study the effect of Foxl2 over-expression on GnRHR gene promoter-luciferase fusion activity. Data generated was analyzed with GraphPad Prism software. RESULTS Microarray analysis identified 996 genes of known function that are potentially regulated by Foxl2 in mouse KK1 granulosa cells. The steroidogenic acute regulatory protein (StAR) gene that has been identified as Foxl2 responsive by others was identified in this study also, thereby supporting the effectiveness of our strategy. The GnRHR gene was chosen for further study because it is known to be expressed in the ovary and the results of previous work has indicated that Foxl2 may regulate GnRHR gene expression. Cellular levels of Foxl2 were increased via transient co-transfection of KK1 cells using a Foxl2 expression vector and a GnRHR promoter-luciferase fusion reporter vector. The results of these analyses indicate that over-expression of Foxl2 resulted in a significant increase in GnRHR promoter activity. Therefore, these transfection data validate the microarray data which suggest that Foxl2 regulates GnRHR and demonstrate that Foxl2 acts as an activator of the GnRHR gene. CONCLUSIONS Potential Foxl2 regulated ovarian genes have been identified through microarray analysis and comparison of these data to other microarray studies. The Foxl2 responsiveness of the GnRHR gene has been validated and provided evidence of Foxl2 transcriptional activation of the GnRHR gene promoter in the mouse ovary derived KK1 granulosa cell line.
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Affiliation(s)
- Jean M Escudero
- Department of Biological and Health Sciences, Texas A&M University- Kingsville, Kingsville, TX, USA
| | - Jodi L Haller
- Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, MD, USA
| | - Colin M Clay
- Department of Biomedical Sciences, Colorado State University, Fort Collins, CO, USA
| | - Kenneth W Escudero
- Department of Biological and Health Sciences, Texas A&M University- Kingsville, Kingsville, TX, USA
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17
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Hu Z, Dandekar D, O'Shaughnessy PJ, De Gendt K, Verhoeven G, Wilkinson MF. Androgen-induced Rhox homeobox genes modulate the expression of AR-regulated genes. Mol Endocrinol 2009; 24:60-75. [PMID: 19901196 DOI: 10.1210/me.2009-0303] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Rhox5, the founding member of the reproductive homeobox on the X chromosome (Rhox) gene cluster, encodes a homeodomain-containing transcription factor that is selectively expressed in Sertoli cells, where it promotes the survival of male germ cells. To identify Rhox5-regulated genes, we generated 15P-1 Sertoli cell clones expressing physiological levels of Rhox5 from a stably transfected expression vector. Microarray analysis identified many genes altered in expression in response to Rhox5, including those encoding proteins controlling cell cycle regulation, apoptosis, metabolism, and cell-cell interactions. Fifteen of these Rhox5-regulated genes were chosen for further analysis. Analysis of Rhox5-null male mice indicated that at least nine of these are Rhox5-regulated in the testes in vivo. Many of them have distinct postnatal expression patterns and are regulated by Rhox5 at different postnatal time points. Most of them are expressed in Sertoli cells, indicating that they are candidates to be directly regulated by Rhox5. Transfection analysis with expression vectors encoding different mouse and human Rhox family members revealed that the regulatory response of a subset of these Rhox5-regulated genes is both conserved and redundant. Given that Rhox5 depends on androgen receptor (AR) for expression in Sertoli cells, we examined whether some Rhox5-regulated genes are also regulated by AR. We provide several lines of evidence that this is the case, leading us to propose that RHOX5 serves as a key intermediate transcription factor that directs some of the actions of AR in the testes.
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Affiliation(s)
- Zhiying Hu
- Department of Biochemistry & Molecular Biology, University of Texas M D Anderson Cancer Center, Houston, Texas 77030, USA
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18
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Shanker S, Hu Z, Wilkinson MF. Epigenetic regulation and downstream targets of the Rhox5 homeobox gene. ACTA ACUST UNITED AC 2008; 31:462-70. [PMID: 18637153 DOI: 10.1111/j.1365-2605.2008.00904.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The discovery of the Rhox homeobox gene cluster on the X chromosome opens up new vistas in the regulation of reproductive processes in mammals. In mice, this cluster comprises more than 30 genes that are selectively expressed in reproductive tissues. A subset of Rhox genes are androgen and AR regulated in postnatal and adult Sertoli cells, making them candidates to mediate androgen-dependent steps during spermatogenesis. The best characterized of these androgen/AR-regulated genes is Rhox5 (Pem), the founding member of the Rhox gene cluster. Targeted deletion of Rhox5 in mice causes male subfertility marked by increased germ-cell apoptosis and decreased sperm count and motility. Microarray analyses identified a wide variety of genes regulated by Rhox5 in Sertoli cells. One of them is the tumour suppressor UNC5C, a pro-apoptotic molecule previously only known to be involved in brain development. Targeted deletion of Unc5c causes decreased germ-cell apoptosis in postnatal and adult testes, indicating that it also has a role in spermatogenesis and supporting a model in which Rhox5 promotes germ-cell survival by downregulating Unc5c. Rhox5 has two independently regulated promoters that have distinct expression patterns. The unique tissue-specific and developmentally regulated transcription pattern of these two promoters appear to be controlled by DNA methylation. Both promoters are methylated in tissues in which they are not expressed, suggesting that DNA methylation serves to repress Rhox5 expression in inappropriate cell types and tissues. In summary, the Rhox gene cluster is an epigenetically regulated set of genes encoding a large number of transcription factors that are strong candidates to regulate gametogenesis and other aspects of reproduction.
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Affiliation(s)
- S Shanker
- Department of Biochemistry and Molecular Biology, University of Texas M. D. Anderson Cancer Center, Houston, TX 77030-4009, USA
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19
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Fayad T, Lefebvre R, Nimpf J, Silversides DW, Lussier JG. Low-Density Lipoprotein Receptor-Related Protein 8 (LRP8) Is Upregulated in Granulosa Cells of Bovine Dominant Follicle: Molecular Characterization and Spatio-Temporal Expression Studies1. Biol Reprod 2007; 76:466-75. [PMID: 17108332 DOI: 10.1095/biolreprod.106.057216] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
The low-density lipoprotein (LDL) receptor-related protein 8 (LRP8) is a member of the LDL receptor family that participates in endocytosis and signal transduction. We cloned the full-length bovine LRP8 cDNA in granulosa cells (GC) of the dominant follicle (DF) as well as several LRP8 mRNA splicing variants, including a variant that contains a proline-rich cytoplasmic insert (A759-K817) that is involved in intracellular signaling. Expression of the A759-K817 variant was analyzed in the GC of follicles at different developmental stages: the small follicle (SF; 2-4 mm), the DF at Day 5 (D5) of the estrus cycle, ovulatory follicles (OF) 24 h after hCG injection, and corpora lutea (CL) at D5. RT-PCR analysis showed that expression was predominant in the GC of DF compared to other follicles and CL (P<0.0001), whereas the expression of other related receptors, such as LDLR and VLDLR, did not show differences. Temporal analyses of follicular walls from the OF following hCG treatment revealed a decrease in LRP8 mRNA expression starting 12 h post-hCG treatment (P<0.0001). LRP8 protein was exclusively localized to the GC, with higher levels in the DF than in the SF (P<0.05). RELN mRNA, which encodes an LRP8 ligand, was highly expressed in the theca of the DF as compared to the OF (P<0.004), whereas MAPK8IP1 mRNA, which encodes an LRP8 intracellular interacting partner, is expressed in the GC of the DF. These results demonstrate the differential expression patterns of LRP8, RELN, and MAPK8IP1 mRNAs during final follicular growth and ovulation, and suggest that a RELN/LRP8/MAPK8IP1 paracrine interaction regulates follicular growth.
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Affiliation(s)
- Tania Fayad
- Centre de Recherche en Reproduction Animale, Faculté de Médecine Vétérinaire, Université de Montréal, St-Hyacinthe, Québec, Canada J2S 7C6
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