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Wen Y, Zhan J, Li C, Li P, Wang C, Wu J, Xu Y, Zhang Y, Zhou Y, Li E, Nie H, Wu X. G-protein couple receptor (GPER1) plays an important role during ovarian folliculogenesis and early development of the Chinese Alligator. Anim Reprod Sci 2023; 255:107295. [PMID: 37422950 DOI: 10.1016/j.anireprosci.2023.107295] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Revised: 06/30/2023] [Accepted: 07/02/2023] [Indexed: 07/11/2023]
Abstract
The critical role of the G protein-coupled receptor 1 (GPER1), a member of the seven-transmembrane G protein-coupled receptor family, in the functional regulation of oocytes accumulated abundant theories in the early research on model animals. However, the full-length cDNA encoding GPER1 and its role in the folliculogenesis has not been illustrated in crocodilians. 0.5, 3, and 12 months old Alligator sinensis cDNA samples were used to clone the full-length cDNA encoding GPER1. Immunolocalization and quantitative analysis were performed using Immunofluorescence technique, RT-PCR and Western blot. Simultaneously, studies on GPER1's promoter deletion and cis-acting transcriptional regulation mechanism were conducted. Immunolocalization staining for the germline marker DDX4 and GPER1 demonstrated that DDX4-positive oocytes were clustered tightly together within the nests, whereas scarcely any detectable GPER1 was present in the oocytes nest in Stage I. After that, occasionally GPER1-positive immunosignal was observed in oocytes and somatic cells additional with the primordial follicles, and it was mainly located at the granulosa cells or thecal cells within the early PFs in the Stage III. The single mutation of the putative SP1 motif, double mutating of Ets/SP1 and SP1/CRE binding sites all depressed promoter activities. This result will help to investigate the role of GPER1 in the early folliculogenesis of A. sinensis.
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Affiliation(s)
- Yue Wen
- College of Life Sciences, Anhui Normal University, Wuhu, Anhui Province, 241000, People's Republic of China; Key Laboratory for Conservation and Use of Important Biological Resources of Anhui Province, People's Republic of China
| | - Jixiang Zhan
- College of Life Sciences, Anhui Normal University, Wuhu, Anhui Province, 241000, People's Republic of China; Key Laboratory for Conservation and Use of Important Biological Resources of Anhui Province, People's Republic of China
| | - Changcheng Li
- College of Life Sciences, Anhui Normal University, Wuhu, Anhui Province, 241000, People's Republic of China; Key Laboratory for Conservation and Use of Important Biological Resources of Anhui Province, People's Republic of China
| | - Pengfei Li
- College of Life Sciences, Anhui Normal University, Wuhu, Anhui Province, 241000, People's Republic of China; Key Laboratory for Conservation and Use of Important Biological Resources of Anhui Province, People's Republic of China
| | - Chong Wang
- College of Life Sciences, Anhui Normal University, Wuhu, Anhui Province, 241000, People's Republic of China; Key Laboratory for Conservation and Use of Important Biological Resources of Anhui Province, People's Republic of China
| | - Jie Wu
- College of Life Sciences, Anhui Normal University, Wuhu, Anhui Province, 241000, People's Republic of China; Key Laboratory for Conservation and Use of Important Biological Resources of Anhui Province, People's Republic of China
| | - Yunlu Xu
- College of Life Sciences, Anhui Normal University, Wuhu, Anhui Province, 241000, People's Republic of China; Key Laboratory for Conservation and Use of Important Biological Resources of Anhui Province, People's Republic of China
| | - Yuqian Zhang
- College of Life Sciences, Anhui Normal University, Wuhu, Anhui Province, 241000, People's Republic of China; Key Laboratory for Conservation and Use of Important Biological Resources of Anhui Province, People's Republic of China
| | - Yongkang Zhou
- Alligator Research Center of Anhui Province, Xuanzhou 242000, People's Republic of China
| | - En Li
- College of Life Sciences, Anhui Normal University, Wuhu, Anhui Province, 241000, People's Republic of China; Key Laboratory for Conservation and Use of Important Biological Resources of Anhui Province, People's Republic of China
| | - Haitao Nie
- College of Life Sciences, Anhui Normal University, Wuhu, Anhui Province, 241000, People's Republic of China; Key Laboratory for Conservation and Use of Important Biological Resources of Anhui Province, People's Republic of China.
| | - Xiaobing Wu
- College of Life Sciences, Anhui Normal University, Wuhu, Anhui Province, 241000, People's Republic of China; Key Laboratory for Conservation and Use of Important Biological Resources of Anhui Province, People's Republic of China.
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2
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Giassetti MI, Miao D, Law NC, Oatley MJ, Park J, Robinson LD, Maddison LA, Bernhardt ML, Oatley JM. ARRDC5 expression is conserved in mammalian testes and required for normal sperm morphogenesis. Nat Commun 2023; 14:2111. [PMID: 37069147 PMCID: PMC10110545 DOI: 10.1038/s41467-023-37735-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Accepted: 03/28/2023] [Indexed: 04/19/2023] Open
Abstract
In sexual reproduction, sperm contribute half the genomic material required for creation of offspring yet core molecular mechanisms essential for their formation are undefined. Here, the α-arrestin molecule arrestin-domain containing 5 (ARRDC5) is identified as an essential regulator of mammalian spermatogenesis. Multispecies testicular tissue transcriptome profiling indicates that expression of Arrdc5 is testis enriched, if not specific, in mice, pigs, cattle, and humans. Knockout of Arrdc5 in mice leads to male specific sterility due to production of low numbers of sperm that are immotile and malformed. Spermiogenesis, the final phase of spermatogenesis when round spermatids transform to spermatozoa, is defective in testes of Arrdc5 deficient mice. Also, epididymal sperm in Arrdc5 knockouts are unable to capacitate and fertilize oocytes. These findings establish ARRDC5 as an essential regulator of mammalian spermatogenesis. Considering the role of arrestin molecules as modulators of cellular signaling and ubiquitination, ARRDC5 is a potential male contraceptive target.
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Affiliation(s)
- Mariana I Giassetti
- Center for Reproductive Biology, Washington State University, Pullman, WA, USA
- School of Molecular Biosciences, College of Veterinary Medicine, Washington State University, Pullman, WA, USA
| | - Deqiang Miao
- Center for Reproductive Biology, Washington State University, Pullman, WA, USA
- School of Molecular Biosciences, College of Veterinary Medicine, Washington State University, Pullman, WA, USA
| | - Nathan C Law
- Center for Reproductive Biology, Washington State University, Pullman, WA, USA
- Department of Animal Sciences, Washington State University, Pullman, WA, USA
| | - Melissa J Oatley
- Center for Reproductive Biology, Washington State University, Pullman, WA, USA
- School of Molecular Biosciences, College of Veterinary Medicine, Washington State University, Pullman, WA, USA
| | - Julie Park
- Center for Reproductive Biology, Washington State University, Pullman, WA, USA
- School of Molecular Biosciences, College of Veterinary Medicine, Washington State University, Pullman, WA, USA
| | - LeeLa D Robinson
- Center for Reproductive Biology, Washington State University, Pullman, WA, USA
- School of Molecular Biosciences, College of Veterinary Medicine, Washington State University, Pullman, WA, USA
| | - Lisette A Maddison
- Center for Reproductive Biology, Washington State University, Pullman, WA, USA
| | - Miranda L Bernhardt
- Center for Reproductive Biology, Washington State University, Pullman, WA, USA
| | - Jon M Oatley
- Center for Reproductive Biology, Washington State University, Pullman, WA, USA.
- School of Molecular Biosciences, College of Veterinary Medicine, Washington State University, Pullman, WA, USA.
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3
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Day TC, Márquez-Zacarías P, Bravo P, Pokhrel AR, MacGillivray KA, Ratcliff WC, Yunker PJ. Varied solutions to multicellularity: The biophysical and evolutionary consequences of diverse intercellular bonds. BIOPHYSICS REVIEWS 2022; 3:021305. [PMID: 35673523 PMCID: PMC9164275 DOI: 10.1063/5.0080845] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Accepted: 04/29/2022] [Indexed: 11/16/2022]
Abstract
The diversity of multicellular organisms is, in large part, due to the fact that multicellularity has independently evolved many times. Nonetheless, multicellular organisms all share a universal biophysical trait: cells are attached to each other. All mechanisms of cellular attachment belong to one of two broad classes; intercellular bonds are either reformable or they are not. Both classes of multicellular assembly are common in nature, having independently evolved dozens of times. In this review, we detail these varied mechanisms as they exist in multicellular organisms. We also discuss the evolutionary implications of different intercellular attachment mechanisms on nascent multicellular organisms. The type of intercellular bond present during early steps in the transition to multicellularity constrains future evolutionary and biophysical dynamics for the lineage, affecting the origin of multicellular life cycles, cell-cell communication, cellular differentiation, and multicellular morphogenesis. The types of intercellular bonds used by multicellular organisms may thus result in some of the most impactful historical constraints on the evolution of multicellularity.
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Affiliation(s)
- Thomas C. Day
- School of Physics, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
| | | | | | - Aawaz R. Pokhrel
- School of Physics, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
| | | | - William C. Ratcliff
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
| | - Peter J. Yunker
- School of Physics, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
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4
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Incomplete abscission and cytoplasmic bridges in the evolution of eukaryotic multicellularity. Curr Biol 2022; 32:R385-R397. [DOI: 10.1016/j.cub.2022.03.021] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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5
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Abstract
Adenosine triphosphate (ATP) serves as the essential source of cellular energy. Over the last two decades, however, ATP has also attracted increasing interest as an extracellular signal that activates purinergic plasma membrane receptors of the P2 family. P2 receptors are divided into two types: ATP-gated nonselective cation channels (P2X) and G protein-coupled receptors (P2Y), the latter being activated by a broad range of purine and pyrimidine nucleotides (ATP, ADP, UTP, and UDP, among others). Purinergic signaling mechanisms are involved in numerous physiological events and pathophysiological conditions. Here, we address the growing body of evidence implicating purinergic signaling in male reproductive system functions. The life-long generation of fertile male germ cells is a highly complex, yet mechanistically poorly understood process. Given the relatively sparse innervation of the testis, spermatogenesis relies on both endocrine control and multi-directional paracrine communication. Therefore, a detailed understanding of such paracrine messengers, including ATP, is crucial to gain mechanistic insight into male reproduction..
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Affiliation(s)
- Nadine Mundt
- Department of Physiology, University of California, San Francisco, San Francisco, CA, United States
- Department of Chemosensation, Institute for Biology II, RWTH Aachen University, Aachen, Germany
- Research Training Group 2416 MultiSenses – MultiScales, RWTH Aachen University, Aachen, Germany
- *Correspondence: Nadine Mundt,
| | - Lina Kenzler
- Department of Chemosensation, Institute for Biology II, RWTH Aachen University, Aachen, Germany
| | - Marc Spehr
- Department of Chemosensation, Institute for Biology II, RWTH Aachen University, Aachen, Germany
- Research Training Group 2416 MultiSenses – MultiScales, RWTH Aachen University, Aachen, Germany
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6
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Dunleavy JEM, O'Connor AE, Okuda H, Merriner DJ, O'Bryan MK. KATNB1 is a master regulator of multiple katanin enzymes in male meiosis and haploid germ cell development. Development 2021; 148:273717. [PMID: 34822718 DOI: 10.1242/dev.199922] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Accepted: 11/16/2021] [Indexed: 12/14/2022]
Abstract
Katanin microtubule-severing enzymes are crucial executers of microtubule regulation. Here, we have created an allelic loss-of-function series of the katanin regulatory B-subunit KATNB1 in mice. We reveal that KATNB1 is the master regulator of all katanin enzymatic A-subunits during mammalian spermatogenesis, wherein it is required to maintain katanin A-subunit abundance. Our data shows that complete loss of KATNB1 from germ cells is incompatible with sperm production, and we reveal multiple new spermatogenesis functions for KATNB1, including essential roles in male meiosis, acrosome formation, sperm tail assembly, regulation of both the Sertoli and germ cell cytoskeletons during sperm nuclear remodelling, and maintenance of seminiferous epithelium integrity. Collectively, our findings reveal that katanins are able to differentially regulate almost all key microtubule-based structures during mammalian male germ cell development, through the complexing of one master controller, KATNB1, with a 'toolbox' of neofunctionalised katanin A-subunits.
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Affiliation(s)
- Jessica E M Dunleavy
- School of Biological Sciences, Faculty of Science, Monash University, Clayton, VIC, 3800, Australia.,School of BioSciences, Faculty of Science, The University of Melbourne, Parkville, VIC, 3010, Australia
| | - Anne E O'Connor
- School of Biological Sciences, Faculty of Science, Monash University, Clayton, VIC, 3800, Australia.,School of BioSciences, Faculty of Science, The University of Melbourne, Parkville, VIC, 3010, Australia
| | - Hidenobu Okuda
- School of Biological Sciences, Faculty of Science, Monash University, Clayton, VIC, 3800, Australia
| | - D Jo Merriner
- School of Biological Sciences, Faculty of Science, Monash University, Clayton, VIC, 3800, Australia.,School of BioSciences, Faculty of Science, The University of Melbourne, Parkville, VIC, 3010, Australia
| | - Moira K O'Bryan
- School of BioSciences, Faculty of Science, The University of Melbourne, Parkville, VIC, 3010, Australia
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7
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Niedenberger BA, Cook K, Baena V, Serra ND, Velte EK, Agno JE, Litwa KA, Terasaki M, Hermann BP, Matzuk MM, Geyer CB. Dynamic cytoplasmic projections connect mammalian spermatogonia in vivo. Development 2018; 145:dev161323. [PMID: 29980567 PMCID: PMC6110146 DOI: 10.1242/dev.161323] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Accepted: 06/27/2018] [Indexed: 01/12/2023]
Abstract
Throughout the male reproductive lifespan, spermatogonial stem cells (SSCs) produce committed progenitors that proliferate and then remain physically connected in growing clones via short cylindrical intercellular bridges (ICBs). These ICBs, which enlarge in meiotic spermatocytes, have been demonstrated to provide a conduit for postmeiotic haploid spermatids to share sex chromosome-derived gene products. In addition to ICBs, spermatogonia exhibit multiple thin cytoplasmic projections. Here, we have explored the nature of these projections in mice and find that they are dynamic, span considerable distances from their cell body (≥25 μm), either terminate or physically connect multiple adjacent spermatogonia, and allow for sharing of macromolecules. Our results extend the current model that subsets of spermatogonia exist as isolated cells or clones, and support a model in which spermatogonia of similar developmental fates are functionally connected through a shared dynamic cytoplasm mediated by thin cytoplasmic projections.
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Affiliation(s)
- Bryan A Niedenberger
- Department of Anatomy and Cell Biology at East Carolina University, Greenville, NC 27834, USA
| | - Kenneth Cook
- Department of Anatomy and Cell Biology at East Carolina University, Greenville, NC 27834, USA
| | - Valentina Baena
- Department of Cell Biology, University of Connecticut Health Center, Farmington, CT 06030, USA
| | - Nicholas D Serra
- Department of Anatomy and Cell Biology at East Carolina University, Greenville, NC 27834, USA
| | - Ellen K Velte
- Department of Anatomy and Cell Biology at East Carolina University, Greenville, NC 27834, USA
| | - Julio E Agno
- Center for Drug Discovery and Department of Pathology and Immunology, Baylor College of Medicine, Houston, TX 77030, USA
| | - Karen A Litwa
- Department of Anatomy and Cell Biology at East Carolina University, Greenville, NC 27834, USA
| | - Mark Terasaki
- Department of Cell Biology, University of Connecticut Health Center, Farmington, CT 06030, USA
| | - Brian P Hermann
- Department of Biology, University of Texas at San Antonio, San Antonio, TX 78249, USA
| | - Martin M Matzuk
- Center for Drug Discovery and Department of Pathology and Immunology, Baylor College of Medicine, Houston, TX 77030, USA
| | - Christopher B Geyer
- Department of Anatomy and Cell Biology at East Carolina University, Greenville, NC 27834, USA
- East Carolina Diabetes and Obesity Institute at East Carolina University, Greenville, NC 27834, USA
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8
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Lee KY, Green RA, Gutierrez E, Gomez-Cavazos JS, Kolotuev I, Wang S, Desai A, Groisman A, Oegema K. CYK-4 functions independently of its centralspindlin partner ZEN-4 to cellularize oocytes in germline syncytia. eLife 2018; 7:36919. [PMID: 29989548 PMCID: PMC6056237 DOI: 10.7554/elife.36919] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2018] [Accepted: 07/09/2018] [Indexed: 12/15/2022] Open
Abstract
Throughout metazoans, germ cells undergo incomplete cytokinesis to form syncytia connected by intercellular bridges. Gamete formation ultimately requires bridge closure, yet how bridges are reactivated to close is not known. The most conserved bridge component is centralspindlin, a complex of the Rho family GTPase-activating protein (GAP) CYK-4/MgcRacGAP and the microtubule motor ZEN-4/kinesin-6. Here, we show that oocyte production by the syncytial Caenorhabditis elegans germline requires CYK-4 but not ZEN-4, which contrasts with cytokinesis, where both are essential. Longitudinal imaging after conditional inactivation revealed that CYK-4 activity is important for oocyte cellularization, but not for the cytokinesis-like events that generate syncytial compartments. CYK-4’s lipid-binding C1 domain and the GTPase-binding interface of its GAP domain were both required to target CYK-4 to intercellular bridges and to cellularize oocytes. These results suggest that the conserved C1-GAP region of CYK-4 constitutes a targeting module required for closure of intercellular bridges in germline syncytia.
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Affiliation(s)
- Kian-Yong Lee
- Ludwig Institute for Cancer Research, Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, United States
| | - Rebecca A Green
- Ludwig Institute for Cancer Research, Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, United States
| | - Edgar Gutierrez
- Department of Physics, University of California, San Diego, La Jolla, United States
| | - J Sebastian Gomez-Cavazos
- Ludwig Institute for Cancer Research, Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, United States
| | - Irina Kolotuev
- Microscopy Rennes Imaging Center and Biosit, University of Rennes 1, Rennes, France
| | - Shaohe Wang
- Ludwig Institute for Cancer Research, Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, United States
| | - Arshad Desai
- Ludwig Institute for Cancer Research, Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, United States
| | - Alex Groisman
- Department of Physics, University of California, San Diego, La Jolla, United States
| | - Karen Oegema
- Ludwig Institute for Cancer Research, Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, United States
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9
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Sinha D, Kalimutho M, Bowles J, Chan AL, Merriner DJ, Bain AL, Simmons JL, Freire R, Lopez JA, Hobbs RM, O'Bryan MK, Khanna KK. Cep55 overexpression causes male-specific sterility in mice by suppressing Foxo1 nuclear retention through sustained activation of PI3K/Akt signaling. FASEB J 2018; 32:4984-4999. [PMID: 29683733 DOI: 10.1096/fj.201701096rr] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Spermatogenesis is a dynamic process involving self-renewal and differentiation of spermatogonial stem cells, meiosis, and ultimately, the differentiation of haploid spermatids into sperm. Centrosomal protein 55 kDa (CEP55) is necessary for somatic cell abscission during cytokinesis. It facilitates equal segregation of cytoplasmic contents between daughter cells by recruiting endosomal sorting complex required for transport machinery (ESCRT) at the midbody. In germ cells, CEP55, in partnership with testes expressed-14 (TEX14) protein, has also been shown to be an integral component of intercellular bridge before meiosis. Various in vitro studies have demonstrated a role for CEP55 in multiple cancers and other diseases. However, its oncogenic potential in vivo remains elusive. To investigate, we generated ubiquitously overexpressing Cep55 transgenic ( Cep55Tg/Tg) mice aiming to characterize its oncogenic role in cancer. Unexpectedly, we found that Cep55Tg/Tg male mice were sterile and had severe and progressive defects in spermatogenesis related to spermatogenic arrest and lack of spermatids in the testes. In this study, we characterized this male-specific phenotype and showed that excessively high levels of Cep55 results in hyperactivation of PI3K/protein kinase B (Akt) signaling in testis. In line with this finding, we observed increased phosphorylation of forkhead box protein O1 (FoxO1), and suppression of its nuclear retention, along with the relative enrichment of promyelocytic leukemia zinc finger (PLZF) -positive cells. Independently, we observed that Cep55 amplification favored upregulation of ret ( Ret) proto-oncogene and glial-derived neurotrophic factor family receptor α-1 ( Gfra1). Consistent with these data, we observed selective down-regulation of genes associated with germ cell differentiation in Cep55-overexpressing testes at postnatal day 10, including early growth response-4 ( Egr4) and spermatogenesis and oogenesis specific basic helix-loop-helix-1 ( Sohlh1). Thus, Cep55 amplification leads to a shift toward the initial maintenance of undifferentiated spermatogonia and ultimately results in progressive germ cell loss. Collectively, our findings demonstrate that Cep55 overexpression causes change in germ cell proportions and manifests as a Sertoli cell only tubule phenotype, similar to that seen in many azoospermic men.-Sinha, D., Kalimutho, M., Bowles, J., Chan, A.-L., Merriner, D. J., Bain, A. L., Simmons, J. L., Freire, R., Lopez, J. A., Hobbs, R. M., O'Bryan, M. K., Khanna, K. K. Cep55 overexpression causes male-specific sterility in mice by suppressing Foxo1 nuclear retention through sustained activation of PI3K/Akt signaling.
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Affiliation(s)
- Debottam Sinha
- Queensland Institute of Medical Research (QIMR) Berghofer Medical Research Institute, Herston, Queensland, Australia.,School of Natural Sciences, Griffith University, Nathan, Queensland, Australia
| | - Murugan Kalimutho
- Queensland Institute of Medical Research (QIMR) Berghofer Medical Research Institute, Herston, Queensland, Australia.,School of Natural Sciences, Griffith University, Nathan, Queensland, Australia
| | - Josephine Bowles
- School of Biomedical Sciences, Institute for Molecular Bioscience, The University of Queensland, St. Lucia, Queensland, Australia
| | - Ai-Leen Chan
- Germline Stem Cell Laboratory, Australian Regenerative Medicine Institute and Monash Biomedicine Discovery Institute, Department of Anatomy and Developmental Biology, Monash University, Clayton, Victoria, Australia
| | - D Jo Merriner
- Male Infertility and Germ Cell Biology Laboratory, the School of Biological Sciences, Monash University, Clayton, Victoria, Australia; and
| | - Amanda L Bain
- Queensland Institute of Medical Research (QIMR) Berghofer Medical Research Institute, Herston, Queensland, Australia
| | - Jacinta L Simmons
- Queensland Institute of Medical Research (QIMR) Berghofer Medical Research Institute, Herston, Queensland, Australia
| | - Raimundo Freire
- Unidad de Investigación, Hospital Universitario de Canarias, Instituto de Tecnologías Biomédicas, Tenerife, Spain
| | - J Alejandro Lopez
- Queensland Institute of Medical Research (QIMR) Berghofer Medical Research Institute, Herston, Queensland, Australia.,School of Natural Sciences, Griffith University, Nathan, Queensland, Australia
| | - Robin M Hobbs
- Germline Stem Cell Laboratory, Australian Regenerative Medicine Institute and Monash Biomedicine Discovery Institute, Department of Anatomy and Developmental Biology, Monash University, Clayton, Victoria, Australia
| | - Moira K O'Bryan
- Male Infertility and Germ Cell Biology Laboratory, the School of Biological Sciences, Monash University, Clayton, Victoria, Australia; and
| | - Kum Kum Khanna
- Queensland Institute of Medical Research (QIMR) Berghofer Medical Research Institute, Herston, Queensland, Australia
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10
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Li XY, Zhang Y, Wang XX, Jin C, Wang YQ, Sun TC, Li J, Tang JX, Batool A, Deng SL, Chen SR, Cheng CY, Liu YX. Regulation of blood-testis barrier assembly in vivo by germ cells. FASEB J 2018; 32:1653-1664. [PMID: 29183964 DOI: 10.1096/fj.201700681r] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The assembly of the blood-testis barrier (BTB) during postnatal development is crucial to support meiosis. However, the role of germ cells in BTB assembly remains unclear. Herein, KitW/KitWV mice were used as a study model. These mice were infertile, failing to establish a functional BTB to support meiosis due to c-Kit mutation. Transplantation of undifferentiated spermatogonia derived from normal mice into the testis of KitW/KitWV mice triggered functional BTB assembly, displaying cyclic remodeling during the epithelial cycle. Also, transplanted germ cells were capable of inducing Leydig cell testosterone production, which could enhance the expression of integral membrane protein claudin 3 in Sertoli cells. Early spermatocytes were shown to play a vital role in directing BTB assembly by expressing claudin 3, which likely created a transient adhesion structure to mediate BTB and cytoskeleton assembly in adjacent Sertoli cells. In summary, the positive modulation of germ cells on somatic cell function provides useful information regarding somatic-germ cell interactions.-Li, X.-Y., Zhang, Y., Wang, X.-X., Jin, C., Wang, Y.-Q., Sun, T.-C., Li, J., Tang, J.-X., Batool, A., Deng, S.-L., Chen, S.-R., Cheng, C. Y., Liu, Y.-X. Regulation of blood-testis barrier assembly in vivo by germ cells.
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Affiliation(s)
- Xiao-Yu Li
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Yan Zhang
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.,Changsha Reproductive Medicine Hospital, Changsha, China; and
| | - Xiu-Xia Wang
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Cheng Jin
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Yu-Qian Wang
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Tie-Cheng Sun
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Jian Li
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Ji-Xin Tang
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Alia Batool
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Shou-Long Deng
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Su-Ren Chen
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - C Yan Cheng
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, New York, USA
| | - Yi-Xun Liu
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
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11
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Abstract
Male infertility is a major and growing problem and, in most cases, the specific root cause is unknown. Here we show that the transcription factor SOX30 plays a critical role in mouse spermatogenesis. Sox30-null mice are healthy and females are fertile, but males are sterile. In the absence of Sox30 meiosis initiates normally in both sexes but, in males, germ cell development arrests during the post-meiotic round spermatid period. In the mutant testis, acrosome and axoneme development are aberrant, multinucleated germ cells (symplasts) form and round spermatids unable to process beyond step 3 of spermiogenesis. No elongated spermatids nor spermatozoa are produced. Thus, Sox30 represents a rare example of a gene for which loss of function results in a complete arrest of spermatogenesis at the onset of spermiogenesis. Our results suggest that SOX30 mutations may underlie some instances of unexplained non-obstructive azoospermia in humans.
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12
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Ibtisham F, Wu J, Xiao M, An L, Banker Z, Nawab A, Zhao Y, Li G. Progress and future prospect of in vitro spermatogenesis. Oncotarget 2017; 8:66709-66727. [PMID: 29029549 PMCID: PMC5630449 DOI: 10.18632/oncotarget.19640] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2017] [Accepted: 07/12/2017] [Indexed: 12/25/2022] Open
Abstract
Infertility has become a major health issue in the world. It affects the social life of couples and of all infertility cases; approximately 40–50% is due to “male factor” infertility. Male infertility could be due to genetic factors, environment or due to gonadotoxic treatment. Developments in reproductive biotechnology have made it possible to rescue fertility and uphold biological fatherhood. In vitro production of haploid male germ cell is a powerful tool, not only for the treatment of infertility including oligozoospermic or azoospermic patient, but also for the fertility preservation in pre-pubertal boys whose gonadal function is threatened by gonadotoxic therapies. Genomic editing of in-vitro cultured germ cells could also potentially cure flaws in spermatogenesis due to genomic mutation. Furthermore, this ex-vivo maturation technique with genomic editing may be used to prevent paternal transmission of genomic diseases. Here, we summarize the historical progress of in vitro spermatogenesis research by using organ and cell culture techniques and the future clinical application of in vitro spermatogenesis.
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Affiliation(s)
- Fahar Ibtisham
- Agricultural College, Guangdong Ocean University, Zhanjiang, Guangdong, China
| | - Jiang Wu
- Agricultural College, Guangdong Ocean University, Zhanjiang, Guangdong, China
| | - Mei Xiao
- Agricultural College, Guangdong Ocean University, Zhanjiang, Guangdong, China
| | - Lilong An
- Agricultural College, Guangdong Ocean University, Zhanjiang, Guangdong, China
| | - Zachary Banker
- Foreign Language College, Guangdong Ocean University, Zhanjiang, Guangdong, China
| | - Aamir Nawab
- Agricultural College, Guangdong Ocean University, Zhanjiang, Guangdong, China
| | - Yi Zhao
- Agricultural College, Guangdong Ocean University, Zhanjiang, Guangdong, China
| | - Guanghui Li
- Agricultural College, Guangdong Ocean University, Zhanjiang, Guangdong, China
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13
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Aponte PM, Caicedo A. Stemness in Cancer: Stem Cells, Cancer Stem Cells, and Their Microenvironment. Stem Cells Int 2017; 2017:5619472. [PMID: 28473858 PMCID: PMC5394399 DOI: 10.1155/2017/5619472] [Citation(s) in RCA: 217] [Impact Index Per Article: 31.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2016] [Revised: 01/31/2017] [Accepted: 02/19/2017] [Indexed: 02/06/2023] Open
Abstract
Stemness combines the ability of a cell to perpetuate its lineage, to give rise to differentiated cells, and to interact with its environment to maintain a balance between quiescence, proliferation, and regeneration. While adult Stem Cells display these properties when participating in tissue homeostasis, Cancer Stem Cells (CSCs) behave as their malignant equivalents. CSCs display stemness in various circumstances, including the sustaining of cancer progression, and the interaction with their environment in search for key survival factors. As a result, CSCs can recurrently persist after therapy. In order to understand how the concept of stemness applies to cancer, this review will explore properties shared between normal and malignant Stem Cells. First, we provide an overview of properties of normal adult Stem Cells. We thereafter elaborate on how these features operate in CSCs. We then review the organization of microenvironment components, which enables CSCs hosting. We subsequently discuss Mesenchymal Stem/Stromal Cells (MSCs), which, although their stemness properties are limited, represent essential components of the Stem Cell niche and tumor microenvironment. We next provide insights of the therapeutic strategies targeting Stem Cell properties in tumors and the use of state-of-the-art techniques in future research. Increasing our knowledge of the CSCs microenvironment is key to identifying new therapeutic solutions.
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Affiliation(s)
- Pedro M. Aponte
- Colegio de Ciencias Biológicas y Ambientales, Universidad San Francisco de Quito (USFQ), 170901 Quito, Ecuador
- Colegio de Ciencias de la Salud, Escuela de Medicina Veterinaria, Universidad San Francisco de Quito (USFQ), 170901 Quito, Ecuador
- Mito-Act Research Consortium, Quito, Ecuador
| | - Andrés Caicedo
- Mito-Act Research Consortium, Quito, Ecuador
- Colegio de Ciencias de la Salud, Escuela de Medicina, Universidad San Francisco de Quito (USFQ), 170901 Quito, Ecuador
- Colegio de Ciencias Biológicas y Ambientales, Instituto de Microbiología, Universidad San Francisco de Quito (USFQ), 170901 Quito, Ecuador
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Gao Y, Cheng CY. Does cell polarity matter during spermatogenesis? SPERMATOGENESIS 2016; 6:e1218408. [PMID: 27635303 DOI: 10.1080/21565562.2016.1218408] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Revised: 07/19/2016] [Accepted: 07/26/2016] [Indexed: 12/21/2022]
Abstract
Cell polarity is crucial to development since apico-basal polarity conferred by the 3 polarity protein modules (or complexes) is essential during embryogenesis, namely the Par (partition defective)-, the CRB (Crumbs)-, and the Scribble-based polarity protein modules. While these protein complexes and their component proteins have been extensively studied in Drosophila and C. elegans and also other mammalian tissues and/or cells, their presence and physiological significance in the testis remain unexplored until the first paper on the Par-based protein published in 2008. Since then, the Par-, the Scribble- and the CRB-based protein complexes and their component proteins in the testis have been studied. These proteins are known to confer Sertoli and spermatid polarity in the seminiferous epithelium, and they are also integrated components of the tight junction (TJ) and the basal ectoplasmic specialization (ES) at the Sertoli cell-cell interface near the basement membrane, which in turn constitute the blood-testis barrier (BTB). These proteins are also found at the apical ES at the Sertoli-spermatid interface. Thus, these polarity proteins also play a significant role in regulating Sertoli and spermatid adhesion in the testis through their actions on actin-based cytoskeletal function. Recent studies have shown that these polarity proteins are having antagonistic effects on the BTB integrity in which the Par6- and CRB3-based polarity complexes promotes the integrity of the Sertoli cell TJ-permeability barrier, whereas the Scribble-based complex promotes restructuring/remodeling of the Sertoli TJ-barrier function. Herein, we carefully evaluate these findings and provide a hypothetic model regarding their role in the testis in the context of the functions of these polarity proteins in other epithelia, so that better experiments can be designed in future studies to explore their significance in spermatogenesis.
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Affiliation(s)
- Ying Gao
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council , New York, NY, USA
| | - C Yan Cheng
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council , New York, NY, USA
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15
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Abstract
Mammalian spermatogenesis is a complex and highly ordered process by which male germ cells proceed through a series of differentiation steps to produce haploid flagellated spermatozoa. Underlying this process is a pool of adult stem cells, the spermatogonial stem cells (SSCs), which commence the spermatogenic lineage by undertaking a differentiation fate decision to become progenitor spermatogonia. Subsequently, progenitors acquire a differentiating spermatogonia phenotype and undergo a series of amplifying mitoses while becoming competent to enter meiosis. After spermatocytes complete meiosis, post-meiotic spermatids must then undergo a remarkable transformation from small round spermatids to a flagellated spermatozoa with extremely compacted nuclei. This chapter reviews the current literature pertaining to spermatogonial differentiation with an emphasis on the mechanisms controlling stem cell fate decisions and early differentiation events in the life of a spermatogonium.
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Affiliation(s)
- Jennifer M Mecklenburg
- Department of Biology, The University of Texas at San Antonio, One UTSA Circle, San Antonio, TX, 78249, USA
| | - Brian P Hermann
- Department of Biology, The University of Texas at San Antonio, One UTSA Circle, San Antonio, TX, 78249, USA.
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16
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Li N, Tang EI, Cheng CY. Regulation of blood-testis barrier by actin binding proteins and protein kinases. Reproduction 2015; 151:R29-41. [PMID: 26628556 DOI: 10.1530/rep-15-0463] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2015] [Accepted: 12/01/2015] [Indexed: 12/13/2022]
Abstract
The blood-testis barrier (BTB) is an important ultrastructure in the testis, since the onset of meiosis and spermiogenesis coincides with the establishment of a functional barrier in rodents and humans. It is also noted that a delay in the assembly of a functional BTB following treatment of neonatal rats with drugs such as diethylstilbestrol or adjudin also delays the first wave of spermiation. While the BTB is one of the tightest blood-tissue barriers, it undergoes extensive remodeling, in particular, at stage VIII of the epithelial cycle to facilitate the transport of preleptotene spermatocytes connected in clones across the immunological barrier. Without this timely transport of preleptotene spermatocytes derived from type B spermatogonia, meiosis will be arrested, causing aspermatogenesis. Yet the biology and regulation of the BTB remains largely unexplored since the morphological studies in the 1970s. Recent studies, however, have shed new light on the biology of the BTB. Herein, we critically evaluate some of these findings, illustrating that the Sertoli cell BTB is regulated by actin-binding proteins (ABPs), likely supported by non-receptor protein kinases, to modulate the organization of actin microfilament bundles at the site. Furthermore, microtubule-based cytoskeleton is also working in concert with the actin-based cytoskeleton to confer BTB dynamics. This timely review provides an update on the unique biology and regulation of the BTB based on the latest findings in the field, focusing on the role of ABPs and non-receptor protein kinases.
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Affiliation(s)
- Nan Li
- The Mary M. Wohlford Laboratory for Male Contraceptive ResearchCenter for Biomedical Research, Population Council, 1230 York Avenue, New York, New York 10065, USA
| | - Elizabeth I Tang
- The Mary M. Wohlford Laboratory for Male Contraceptive ResearchCenter for Biomedical Research, Population Council, 1230 York Avenue, New York, New York 10065, USA
| | - C Yan Cheng
- The Mary M. Wohlford Laboratory for Male Contraceptive ResearchCenter for Biomedical Research, Population Council, 1230 York Avenue, New York, New York 10065, USA
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17
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Busada JT, Geyer CB. The Role of Retinoic Acid (RA) in Spermatogonial Differentiation. Biol Reprod 2015; 94:10. [PMID: 26559678 PMCID: PMC4809555 DOI: 10.1095/biolreprod.115.135145] [Citation(s) in RCA: 67] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2015] [Accepted: 11/06/2015] [Indexed: 12/22/2022] Open
Abstract
Retinoic acid (RA) directs the sequential, but distinct, programs of spermatogonial differentiation and meiotic differentiation that are both essential for the generation of functional spermatozoa. These processes are functionally and temporally decoupled, as they occur in distinct cell types that arise over a week apart, both in the neonatal and adult testis. However, our understanding is limited in terms of what cellular and molecular changes occur downstream of RA exposure that prepare differentiating spermatogonia for meiotic initiation. In this review, we describe the process of spermatogonial differentiation and summarize the current state of knowledge regarding RA signaling in spermatogonia.
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Affiliation(s)
- Jonathan T Busada
- Department of Anatomy and Cell Biology, Brody School of Medicine, East Carolina University, Greenville, North Carolina
| | - Christopher B Geyer
- Department of Anatomy and Cell Biology, Brody School of Medicine, East Carolina University, Greenville, North Carolina East Carolina Diabetes and Obesity Institute, Brody School of Medicine, East Carolina University, Greenville, North Carolina
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18
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Mruk DD, Cheng CY. The Mammalian Blood-Testis Barrier: Its Biology and Regulation. Endocr Rev 2015; 36:564-91. [PMID: 26357922 PMCID: PMC4591527 DOI: 10.1210/er.2014-1101] [Citation(s) in RCA: 388] [Impact Index Per Article: 43.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/09/2014] [Accepted: 09/03/2015] [Indexed: 12/31/2022]
Abstract
Spermatogenesis is the cellular process by which spermatogonia develop into mature spermatids within seminiferous tubules, the functional unit of the mammalian testis, under the structural and nutritional support of Sertoli cells and the precise regulation of endocrine factors. As germ cells develop, they traverse the seminiferous epithelium, a process that involves restructuring of Sertoli-germ cell junctions, as well as Sertoli-Sertoli cell junctions at the blood-testis barrier. The blood-testis barrier, one of the tightest tissue barriers in the mammalian body, divides the seminiferous epithelium into 2 compartments, basal and adluminal. The blood-testis barrier is different from most other tissue barriers in that it is not only comprised of tight junctions. Instead, tight junctions coexist and cofunction with ectoplasmic specializations, desmosomes, and gap junctions to create a unique microenvironment for the completion of meiosis and the subsequent development of spermatids into spermatozoa via spermiogenesis. Studies from the past decade or so have identified the key structural, scaffolding, and signaling proteins of the blood-testis barrier. More recent studies have defined the regulatory mechanisms that underlie blood-testis barrier function. We review here the biology and regulation of the mammalian blood-testis barrier and highlight research areas that should be expanded in future studies.
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Affiliation(s)
- Dolores D Mruk
- Center for Biomedical Research, Population Council, New York, New York 10065
| | - C Yan Cheng
- Center for Biomedical Research, Population Council, New York, New York 10065
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Rabionet M, Bayerle A, Jennemann R, Heid H, Fuchser J, Marsching C, Porubsky S, Bolenz C, Guillou F, Gröne HJ, Gorgas K, Sandhoff R. Male meiotic cytokinesis requires ceramide synthase 3-dependent sphingolipids with unique membrane anchors. Hum Mol Genet 2015; 24:4792-808. [DOI: 10.1093/hmg/ddv204] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2015] [Accepted: 05/29/2015] [Indexed: 12/11/2022] Open
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20
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Ben-David G, Miller E, Steinhauer J. Drosophila spermatid individualization is sensitive to temperature and fatty acid metabolism. SPERMATOGENESIS 2015; 5:e1006089. [PMID: 26413411 PMCID: PMC4581069 DOI: 10.1080/21565562.2015.1006089] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/23/2014] [Revised: 12/15/2014] [Accepted: 01/06/2015] [Indexed: 12/18/2022]
Abstract
Fatty acids are precursors of potent lipid signaling molecules. They are stored in membrane phospholipids and released by phospholipase A2 (PLA2). Lysophospholipid acyltransferases (ATs) oppose PLA2 by re-esterifying fatty acids into phospholipids, in a biochemical pathway known as the Lands Cycle. Drosophila Lands Cycle ATs oys and nes, as well as 7 predicted PLA2 genes, are expressed in the male reproductive tract. Oys and Nes are required for spermatid individualization. Individualization, which occurs after terminal differentiation, invests each spermatid in its own plasma membrane and removes the bulk of the cytoplasmic contents. We developed a quantitative assay to measure individualization defects. We demonstrate that individualization is sensitive to temperature and age but not to diet. Mutation of the cyclooxygenase Pxt, which metabolizes fatty acids to prostaglandins, also leads to individualization defects. In contrast, modulating phospholipid levels by mutation of the phosphatidylcholine lipase Swiss cheese (Sws) or the ethanolamine kinase Easily shocked (Eas) does not perturb individualization, nor does Sws overexpression. Our results suggest that fatty acid derived signals such as prostaglandins, whose abundance is regulated by the Lands Cycle, are important regulators of spermatogenesis.
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Affiliation(s)
| | - Eli Miller
- Department of Biology; Yeshiva University ; New York, NY USA
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21
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O'Donnell L. Mechanisms of spermiogenesis and spermiation and how they are disturbed. SPERMATOGENESIS 2015; 4:e979623. [PMID: 26413397 DOI: 10.4161/21565562.2014.979623] [Citation(s) in RCA: 151] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 05/26/2014] [Accepted: 10/16/2014] [Indexed: 11/19/2022]
Abstract
Haploid round spermatids undergo a remarkable transformation during spermiogenesis. The nucleus polarizes to one side of the cell as the nucleus condenses and elongates, and the microtubule-based manchette sculpts the nucleus into its species-specific head shape. The assembly of the central component of the sperm flagellum, known as the axoneme, begins early in spermiogenesis, and is followed by the assembly of secondary structures needed for normal flagella. The final remodelling of the mature elongated spermatid occurs during spermiation, when the spermatids line up along the luminal edge, shed their residual cytoplasm and are ultimately released into the lumen. Defects in spermiogenesis and spermiation are manifested as low sperm number, abnormal sperm morphology and poor motility and are commonly observed during reproductive toxicant administration, as well as in genetically modified mouse models of male infertility. This chapter summarizes the major physiological processes and the most commonly observed defects in spermiogenesis and spermiation, to aid in the diagnosis of the potential mechanisms that could be perturbed by experimental manipulation such as reproductive toxicant administration.
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Affiliation(s)
- Liza O'Donnell
- MIMR-PHI Institute of Medical Research ; Clayton, Victoria, Australia ; Department of Anatomy and Developmental Biology; Monash University ; Clayton, Victoria, Australia
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22
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Haglund K, Nezis IP, Stenmark H. Structure and functions of stable intercellular bridges formed by incomplete cytokinesis during development. Commun Integr Biol 2014. [DOI: 10.4161/cib.13550] [Citation(s) in RCA: 123] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
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23
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Allais-Bonnet A, Pailhoux E. Role of the prion protein family in the gonads. Front Cell Dev Biol 2014; 2:56. [PMID: 25364761 PMCID: PMC4207050 DOI: 10.3389/fcell.2014.00056] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2014] [Accepted: 09/12/2014] [Indexed: 01/17/2023] Open
Abstract
The prion-gene family comprises four members named PRNP (PRPc), PRND (Doppel), PRNT (PRT), and SPRN (Shadoo). According to species, PRND is located 16–52 kb downstream from the PRNP locus, whereas SPRN is located on another chromosome. The fourth prion-family gene, PRNT, belongs to the same genomic cluster as PRNP and PRND in humans and bovidae. PRNT and PRND possibly resulted from a duplication event of PRND and PRNP, respectively, that occurred early during eutherian species divergence. Although most of the studies concerning the prion-family has been done on PRPc and its involvement in transmissible neurodegenerative disorders, different works report some potential roles of these proteins in the reproductive function of both sexes. Among them, a clear role of PRND, that encodes for the Doppel protein, in male fertility has been demonstrated through gene targeting studies in mice. In other species, Doppel seems to play a role in testis and ovary development but its cellular localization is variable according to the gonadal developmental stage and to the mammalian species considered. For the other three genes, their roles in reproductive function appear ill-defined and/or controversial. The present review aimed to synthesize all the available data on these prion-family members and their relations with reproductive processes, mainly in the gonad of both sexes.
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Affiliation(s)
- Aurélie Allais-Bonnet
- Institut National de la Recherche Agronomique, UMR 1198, Biologie du Développement et Reproduction Jouy-en-Josas, France
| | - Eric Pailhoux
- Institut National de la Recherche Agronomique, UMR 1198, Biologie du Développement et Reproduction Jouy-en-Josas, France
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Salaheldeen E, Howida A, Wakayama T, Iida H. CEACAM2-L on spermatids interacts with poliovirus receptor on Sertoli cells in mouse seminiferous epithelium. J Histochem Cytochem 2014; 62:632-44. [PMID: 24948196 DOI: 10.1369/0022155414542653] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The removal of excess cytoplasm from elongated spermatids by Sertoli cells is the last essential step in spermatogenesis. It requires cell-to-cell recognition between a Sertoli cell and an elongating spermatid through protein-protein interactions. CEACAM2-L, an adhesion molecule of the immunoglobulin superfamily (IgSF), is present at the plasma membrane covering the excess cytoplasm of elongated spermatids, and is possibly involved in the cell-to-cell recognition. In this study, we investigated the interaction between CEACAM2-L and Poliovirus receptor (PVR), which is also from the IgSF and is expressed by Sertoli cells. Immunohistochemical analysis showed that CEACAM2-L expressed on elongated spermatids was in close contact with PVR-positive cell processes of Sertoli cells. Immunoprecipitation experiments both in vivo and in vitro demonstrated a direct heterophilic interaction between CEACAM2-L and PVR. We show that the N-terminal Ig domain of CEACAM2-L was critical for its interaction with PVR. In addition, we found that CEACAM2-L formed heterophilic trans-tetramers with PVR in transfected COS-7 cells. From these data, we propose that Sertoli cells recognize the excess cytoplasm of elongated spermatids through the PVR-CEACAM2-L interaction in mouse testis.
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Affiliation(s)
- Elsaid Salaheldeen
- Laboratory of Zoology, Graduate School of Agriculture, Kyushu University, Higashiku Hakozaki 6-10-1, Fukuoka 812-8581 Japan (ES, AH, HI)Zoology Department, Faculty of Science, Sohag University, Sohag, Naser City, Egypt, PO.82524 (ES, AH)Department of Histology and Embryology, Graduate School of Medical Science, Kanazawa University, Kanazawa 920-8640, Japan (TW)
| | - Ali Howida
- Laboratory of Zoology, Graduate School of Agriculture, Kyushu University, Higashiku Hakozaki 6-10-1, Fukuoka 812-8581 Japan (ES, AH, HI)Zoology Department, Faculty of Science, Sohag University, Sohag, Naser City, Egypt, PO.82524 (ES, AH)Department of Histology and Embryology, Graduate School of Medical Science, Kanazawa University, Kanazawa 920-8640, Japan (TW)
| | - Tomohiko Wakayama
- Laboratory of Zoology, Graduate School of Agriculture, Kyushu University, Higashiku Hakozaki 6-10-1, Fukuoka 812-8581 Japan (ES, AH, HI)Zoology Department, Faculty of Science, Sohag University, Sohag, Naser City, Egypt, PO.82524 (ES, AH)Department of Histology and Embryology, Graduate School of Medical Science, Kanazawa University, Kanazawa 920-8640, Japan (TW)
| | - Hiroshi Iida
- Laboratory of Zoology, Graduate School of Agriculture, Kyushu University, Higashiku Hakozaki 6-10-1, Fukuoka 812-8581 Japan (ES, AH, HI)Zoology Department, Faculty of Science, Sohag University, Sohag, Naser City, Egypt, PO.82524 (ES, AH)Department of Histology and Embryology, Graduate School of Medical Science, Kanazawa University, Kanazawa 920-8640, Japan (TW)
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25
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Gadella BM, Luna C. Cell biology and functional dynamics of the mammalian sperm surface. Theriogenology 2014; 81:74-84. [DOI: 10.1016/j.theriogenology.2013.09.005] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2013] [Revised: 09/07/2013] [Accepted: 09/08/2013] [Indexed: 12/11/2022]
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26
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Mandal A, Datta AK, Gupta S, Paul R, Saha A, Ghosh BK, Bhattacharya A, Iqbal M. Cytomixis--a unique phenomenon in animal and plant. PROTOPLASMA 2013; 250:985-996. [PMID: 23475075 DOI: 10.1007/s00709-013-0493-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2012] [Accepted: 02/27/2013] [Indexed: 06/01/2023]
Abstract
Cytomixis is reported to be a uniform phenomenon in the context of fertilization during spermatogenesis of animals and in some lower groups of plants where oogamous reproduction prevails. However, the phenomenon is versatile in flowering taxa as it lacks uniformity in occurrences, causes, formation of intercellular bridges, involvement of number of cells in a cluster, evolutionary significance among others. A review on cytomixis is conducted with an objective that it may offer a scope to unravel some of the ambiguities associated with it and provide further information on cell, reproductive, structural and evolutionary biology.
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Affiliation(s)
- Aninda Mandal
- Department of Botany, Cytogenetics, Genetics and Plant Breeding Section, University of Kalyani, Kalyani, 741235, West Bengal, India
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27
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Fujiwara Y, Ogonuki N, Inoue K, Ogura A, Handel MA, Noguchi J, Kunieda T. t-SNARE Syntaxin2 (STX2) is implicated in intracellular transport of sulfoglycolipids during meiotic prophase in mouse spermatogenesis. Biol Reprod 2013; 88:141. [PMID: 23595907 DOI: 10.1095/biolreprod.112.107110] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Syntaxin2 (STX2), also known as epimorphin, is a member of the SNARE family of proteins, with expression in various types of cells. We previously identified an ENU-induced mutation, repro34, in the mouse Stx2 gene. The Stx2(repro34) mutation causes male-restricted infertility due to syncytial multinucleation of spermatogenic cells during meiotic prophase. A similar phenotype is also observed in mice with targeted inactivation of Stx2, as well as in mice lacking enzymes involved in sulfoglycolipid synthesis. Herein we analyzed expression and subcellular localization of STX2 and sulfoglycolipids in spermatogenesis. The STX2 protein localizes to the cytoplasm of germ cells at the late pachytene stage. It is found in a distinct subcellular pattern, presumably in the Golgi apparatus of pachytene/diplotene spermatocytes. Sulfoglycolipids are produced in the Golgi apparatus and transported to the plasma membrane. In Stx2(repro34) mutants, sulfoglycolipids are aberrantly localized in both pachytene/diplotene spermatocytes and in multinucleated germ cells. These results suggest that STX2 plays roles in transport and/or subcellular distribution of sulfoglycolipids. STX2 function in the Golgi apparatus and sulfoglycolipids may be essential for maintenance of the constriction between neighboring developing spermatocytes, which ensures ultimate individualization of germ cells in later stages of spermatogenesis.
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Affiliation(s)
- Yasuhiro Fujiwara
- Graduate School of Natural Science and Technology, Okayama University, Okayama, Okayama, Japan
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28
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McClusky LM. Coordination of spermatogenic processes in the testis: lessons from cystic spermatogenesis. Cell Tissue Res 2013; 349:703-15. [PMID: 22314845 DOI: 10.1007/s00441-011-1288-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2011] [Accepted: 11/11/2011] [Indexed: 12/21/2022]
Abstract
A common observation in the vertebrate testis is that new germ cell clones enter spermatogenesis proper before previously formed clones have completed their development. The extent to which the developmental advance of any given germ cell clone in any phase of spermatogenesis is dependent on that of neighboring clones and/or on the coordinating influence of associated Sertoli cells in the immediate vicinity or of others further away remains unclear. This review presents an overall synthesis of findings in an ancient vertebrate, the spiny dogfish shark and shows that, even at this phyletic level, the developmental advance of a given germ cell clone is the outcome of various processes emanating from its spatiotemporal relationship with (1) its own complement of Sertoli cells in the anatomically distinct spermatocyst and (2) Sertoli cells associated with other germ cell clones that lie upstream or downstream in the spermatogenic progression and that secrete, among others, androgen and estrogen destined for target sites upstream. Analysis of the protracted spermatogenic cycle shows the coordination in space and time of spermatogenic and steroidogenic events. Furthermore, the natural withdrawal of pituitary gonadotropin support in the dogfish causes a distinct and highly ordered gradient of apoptosis among the spermatogonial generations; this in turn is a major contributing factor to the cyclic nature of sperm production observed in this lower vertebrate. Because of the simplicity of their testicular organization, their cystic spermatogenesis and their phylogenetic position, cartilaginous fishes constitute a valid vertebrate reference system for comparative analysis with higher vertebrates.
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Zhou K, Rolls MM, Hanna-Rose W. A postmitotic function and distinct localization mechanism for centralspindlin at a stable intercellular bridge. Dev Biol 2013; 376:13-22. [PMID: 23370148 DOI: 10.1016/j.ydbio.2013.01.020] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2013] [Revised: 01/17/2013] [Accepted: 01/19/2013] [Indexed: 10/27/2022]
Abstract
Centralspindlin, a complex composed of the subunits ZEN-4 and CYK-4, recruits and regulates proteins that modulate the actin cytoskeleton to promote cleavage furrow formation and progression during cytokinesis. The ZEN-4 subunit is a kinesin that is proposed to function primarily by bundling microtubules and promoting transport of the complex to the midzone. ZEN-4 and CYK-4 are mutually dependent for localization to the midzone during cytokinesis. Once at the midzone, the CYK-4 subunit functions to recruit actin regulators and the scaffold anillin as well as to regulate RhoA and Rac via its intrinsic GAP domain, ultimately promoting actomyosin contractile ring assembly. We have revealed a distinct mechanism for centralspindlin localization and function at a stable, postmitotic intercellular bridge in the Caenorhabditis elegans gonad. Loss of zen-4 or cyk-4 function disrupts germ cell progression postmitotically. In contrast to the localization and recruitment relationships during mitosis, centralspindlin is maintained at the intercellular bridge by anillin, and CYK-4 is localized independently of ZEN-4 but not vice versa. We present evidence that centralspindlin function at the rachis bridge involves ZEN-4 action on the microtubules as opposed to the regulation of the actin cytoskeleton mediated by CYK-4 during cytokinesis.
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Affiliation(s)
- Kang Zhou
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA 16802, USA
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30
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Abstract
The blood-testis barrier includes strands of tight junctions between somatic Sertoli cells that restricts solutes from crossing the paracellular space, creating a microenvironment within seminiferous tubules and providing immune privilege to meiotic and postmeiotic cells. Large cysts of germ cells transit the Sertoli cell tight junctions (SCTJs) without compromising their integrity. We used confocal microscopy to visualize SCTJ components during germ cell cyst migration across the SCTJs. Cysts become enclosed within a network of transient compartments fully bounded by old and new tight junctions. Dissolution of the old tight junctions releases the germ cells into the adluminal compartment, thus completing transit across the blood-testis barrier. Claudin 3, a tight junction protein, is transiently incorporated into new tight junctions and then replaced by claudin 11.
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Affiliation(s)
- Benjamin E Smith
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA 98195, USA
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31
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Abstract
The blood-testis barrier (BTB) is one of the tightest blood-tissue barriers in the mammalian body. It divides the seminiferous epithelium into the basal and the apical (adluminal) compartments. Meiosis I and II, spermiogenesis, and spermiation all take place in a specialized microenvironment behind the BTB in the apical compartment, but spermatogonial renewal and differentiation and cell cycle progression up to the preleptotene spermatocyte stage take place outside of the BTB in the basal compartment of the epithelium. However, the BTB is not a static ultrastructure. Instead, it undergoes extensive restructuring during the seminiferous epithelial cycle of spermatogenesis at stage VIII to allow the transit of preleptotene spermatocytes at the BTB. Yet the immunological barrier conferred by the BTB cannot be compromised, even transiently, during the epithelial cycle to avoid the production of antibodies against meiotic and postmeiotic germ cells. Studies have demonstrated that some unlikely partners, namely adhesion protein complexes (e.g., occludin-ZO-1, N-cadherin-β-catenin, claudin-5-ZO-1), steroids (e.g., testosterone, estradiol-17β), nonreceptor protein kinases (e.g., focal adhesion kinase, c-Src, c-Yes), polarity proteins (e.g., PAR6, Cdc42, 14-3-3), endocytic vesicle proteins (e.g., clathrin, caveolin, dynamin 2), and actin regulatory proteins (e.g., Eps8, Arp2/3 complex), are working together, apparently under the overall influence of cytokines (e.g., transforming growth factor-β3, tumor necrosis factor-α, interleukin-1α). In short, a "new" BTB is created behind spermatocytes in transit while the "old" BTB above transiting cells undergoes timely degeneration, so that the immunological barrier can be maintained while spermatocytes are traversing the BTB. We also discuss recent findings regarding the molecular mechanisms by which environmental toxicants (e.g., cadmium, bisphenol A) induce testicular injury via their initial actions at the BTB to elicit subsequent damage to germ-cell adhesion, thereby leading to germ-cell loss, reduced sperm count, and male infertility or subfertility. Moreover, we also critically evaluate findings in the field regarding studies on drug transporters in the testis and discuss how these influx and efflux pumps regulate the entry of potential nonhormonal male contraceptives to the apical compartment to exert their effects. Collectively, these findings illustrate multiple potential targets are present at the BTB for innovative contraceptive development and for better delivery of drugs to alleviate toxicant-induced reproductive dysfunction in men.
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Affiliation(s)
- C Yan Cheng
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, 1230 York Avenue, New York, NY 10065, USA.
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32
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Lacroix B, Maddox AS. Cytokinesis, ploidy and aneuploidy. J Pathol 2011; 226:338-51. [DOI: 10.1002/path.3013] [Citation(s) in RCA: 94] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2011] [Revised: 09/22/2011] [Accepted: 09/24/2011] [Indexed: 12/21/2022]
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Greenbaum MP, Iwamori T, Buchold GM, Matzuk MM. Germ cell intercellular bridges. Cold Spring Harb Perspect Biol 2011; 3:a005850. [PMID: 21669984 DOI: 10.1101/cshperspect.a005850] [Citation(s) in RCA: 156] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Stable intercellular bridges are a conserved feature of gametogenesis in multicellular animals observed more than 100 years ago, but their function was unknown. Many of the components necessary for this structure have been identified through the study of cytokinesis in Drosophila; however, mammalian intercellular bridges have distinct properties from those of insects. Mammalian germ cell intercellular bridges are composed of general cytokinesis components with additional germ cell-specific factors including TEX14. TEX14 is an inactive kinase essential for the maintenance of stable intercellular bridges in gametes of both sexes but whose loss specifically impairs male meiosis. TEX14 acts to impede the terminal steps of abscission by competing for essential component CEP55, blocking its interaction in nongerm cells with ALIX and TSG101. Additionally, TEX14-interacting protein RBM44, whose localization in stabile intercellular bridges is limited to pachytene and secondary spermatocytes, may participate in processes such as RNA transport but is nonessential to the maintenance of intercellular bridge stability.
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Affiliation(s)
- Michael P Greenbaum
- Department of Radiation Oncology, Baylor College of Medicine, Houston, Texas 77030, USA
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Haglund K, Nezis IP, Stenmark H. Structure and functions of stable intercellular bridges formed by incomplete cytokinesis during development. Commun Integr Biol 2011; 4:1-9. [PMID: 21509167 DOI: 10.4161/cib.4.1.13550] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2010] [Accepted: 09/08/2010] [Indexed: 01/12/2023] Open
Abstract
Cytokinesis, the final step of cell division, normally proceeds to completion in living organisms, so that daughter cells physically separate by abscission. In certain tissues and developmental stages, on the other hand, the cytokinesis process is incomplete, giving rise to cells interconnected in syncytia by stable intercellular bridges. This evolutionarily conserved physiological process occurs in the female and male germline in species ranging from insects to humans, and has also been observed in some somatic tissues in invertebrates. Stable intercellular bridges have fascinated cell biologists ever since they were first described more than 50 years ago, and even though substantial progress has been made concerning their ultrastructure and molecular composition, much remains to be understood about their biological functions. Another major question is by which mechanisms complete versus incomplete cytokinesis is determined. In this mini-review we will try to give an overview of the current knowledge about the structure, composition and functions of stable intercellular bridges, and discuss recent insights into the molecular control of the incomplete cytokinesis process.
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Affiliation(s)
- Kaisa Haglund
- Department of Biochemistry; Institute for Cancer Research; Oslo University Hospital; Centre for Cancer Biomedicine; Faculty of Medicine; University of Oslo; Montebello, Oslo, Norway
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35
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Kopanja D, Roy N, Stoyanova T, Hess RA, Bagchi S, Raychaudhuri P. Cul4A is essential for spermatogenesis and male fertility. Dev Biol 2011; 352:278-87. [PMID: 21291880 DOI: 10.1016/j.ydbio.2011.01.028] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2010] [Revised: 01/20/2011] [Accepted: 01/24/2011] [Indexed: 02/04/2023]
Abstract
The mammalian Cul4 genes, Cul4A and Cul4B, encode the scaffold components of the cullin-based E3 ubiquitin ligases. The two Cul4 genes are functionally redundant. Recent study indicated that mice expressing a truncated CUL4A that fails to interact with its functional partner ROC1 exhibit no developmental phenotype. We generated a Cul4A-/- strain lacking exons 4-8 that does not express any detectable truncated protein. In this strain, the male mice are infertile and exhibit severe deficiencies in spermatogenesis. The primary spermatocytes are deficient in progression through late prophase I, a time point when expression of the X-linked Cul4B gene is silenced due to meiotic sex chromosome inactivation. Testes of the Cul4A-/- mice exhibit extensive apoptosis. Interestingly, the pachytene spermatocytes exhibit persistent double stranded breaks, suggesting a deficiency in homologous recombination. Also, we find that CUL4A localizes to the double stranded breaks generated in pre-pachytene spermatocytes. The observations identify a novel function of CUL4A in meiotic recombination and demonstrate an essential role of CUL4A in spermatogenesis.
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Affiliation(s)
- Dragana Kopanja
- Department of Biochemistry and Molecular Genetics (M/C 669), University of Illinois, College of Medicine, 900 S. Ashland Ave, Chicago, IL-60607, USA
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36
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Xu G, Vogel KS, McMahan CA, Herbert DC, Walter CA. BAX and tumor suppressor TRP53 are important in regulating mutagenesis in spermatogenic cells in mice. Biol Reprod 2010; 83:979-87. [PMID: 20739667 DOI: 10.1095/biolreprod.110.085415] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
During the first wave of spermatogenesis, and in response to ionizing radiation, elevated mutant frequencies are reduced to a low level by unidentified mechanisms. Apoptosis is occurring in the same time frame that the mutant frequency declines. We examined the role of apoptosis in regulating mutant frequency during spermatogenesis. Apoptosis and mutant frequencies were determined in spermatogenic cells obtained from Bax-null or Trp53-null mice. The results showed that spermatogenic lineage apoptosis was markedly decreased in Bax-null mice and was accompanied by a significantly increased spontaneous mutant frequency in seminiferous tubule cells compared to that of wild-type mice. Apoptosis profiles in the seminiferous tubules for Trp53-null were similar to control mice. Spontaneous mutant frequencies in pachytene spermatocytes and in round spermatids from Trp53-null mice were not significantly different from those of wild-type mice. However, epididymal spermatozoa from Trp53-null mice displayed a greater spontaneous mutant frequency compared to that from wild-type mice. A greater proportion of spontaneous transversions and a greater proportion of insertions/deletions 15 days after ionizing radiation were observed in Trp53-null mice compared to wild-type mice. Base excision repair activity in mixed germ cell nuclear extracts prepared from Trp53-null mice was significantly lower than that for wild-type controls. These data indicate that BAX-mediated apoptosis plays a significant role in regulating spontaneous mutagenesis in seminiferous tubule cells obtained from neonatal mice, whereas tumor suppressor TRP53 plays a significant role in regulating spontaneous mutagenesis between postmeiotic round spermatid and epididymal spermatozoon stages of spermiogenesis.
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Affiliation(s)
- Guogang Xu
- Department of Cellular & Structural Biology, University of Texas Health Science Center at San Antonio, San Antonio, Texas, USA
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37
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Miething A. Local desynchronization of cellular development within mammalian male germ cell clones. Ann Anat 2010; 192:247-50. [DOI: 10.1016/j.aanat.2010.06.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2010] [Revised: 06/07/2010] [Accepted: 06/30/2010] [Indexed: 11/26/2022]
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Chang YC, Chen YJ, Wu CH, Wu YC, Yen TC, Ouyang P. Characterization of centrosomal proteins Cep55 and pericentrin in intercellular bridges of mouse testes. J Cell Biochem 2010; 109:1274-85. [PMID: 20186884 DOI: 10.1002/jcb.22517] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Centrosomal protein 55 (Cep55), located in the centrosome in interphase cells and recruited to the midbody during cytokinesis, is essential for completion of cell abscission. Northern blot previously showed that a high level of Cep55 is predominantly expressed in the testis. In the present study, we examined the spatial and temporal expression patterns of Cep55 during mouse testis maturation. We found that Cep55, together with pericentrin, another centrosomal protein, were localized to the intercellular bridges (IBs) interconnecting spermatogenic cells in a syncytium. The IBs were elaborated as a double ring structure formed by an inner ring decorated by Cep55 or pericentrin and an outer ring of mitotic kinesin-like protein 1 (MKLP1) in the male germ cell in early postnatal stages and adulthood. In addition, Cep55 and pericentrin were also localized to the acrosome region and flagellum neck and middle piece in elongated spermatids, respectively. These results suggest that Cep55 and pericentrin are required for the stable bridge between germ cells during spermatogenesis and spermiogenesis.
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Affiliation(s)
- Yu-Chen Chang
- Graduate Institute of Clinical Medical Sciences, College of Medicine, Chang Gung University, Tao-Yuan, Taiwan, ROC
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39
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Hermo L, Pelletier RM, Cyr DG, Smith CE. Surfing the wave, cycle, life history, and genes/proteins expressed by testicular germ cells. Part 4: intercellular bridges, mitochondria, nuclear envelope, apoptosis, ubiquitination, membrane/voltage-gated channels, methylation/acetylation, and transcription factors. Microsc Res Tech 2010; 73:364-408. [PMID: 19941288 DOI: 10.1002/jemt.20785] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
As germ cells divide and differentiate from spermatogonia to spermatozoa, they share a number of structural and functional features that are common to all generations of germ cells and these features are discussed herein. Germ cells are linked to one another by large intercellular bridges which serve to move molecules and even large organelles from the cytoplasm of one cell to another. Mitochondria take on different shapes and features and topographical arrangements to accommodate their specific needs during spermatogenesis. The nuclear envelope and pore complex also undergo extensive modifications concomitant with the development of germ cell generations. Apoptosis is an event that is normally triggered by germ cells and involves many proteins. It occurs to limit the germ cell pool and acts as a quality control mechanism. The ubiquitin pathway comprises enzymes that ubiquitinate as well as deubiquitinate target proteins and this pathway is present and functional in germ cells. Germ cells express many proteins involved in water balance and pH control as well as voltage-gated ion channel movement. In the nucleus, proteins undergo epigenetic modifications which include methylation, acetylation, and phosphorylation, with each of these modifications signaling changes in chromatin structure. Germ cells contain specialized transcription complexes that coordinate the differentiation program of spermatogenesis, and there are many male germ cell-specific differences in the components of this machinery. All of the above features of germ cells will be discussed along with the specific proteins/genes and abnormalities to fertility related to each topic.
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Affiliation(s)
- Louis Hermo
- Department of Anatomy and Cell Biology, Faculty of Medicine, McGill University, 3640 University Street, Montreal, QC Canada H3A 2B2.
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40
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Chung SSW, Choi C, Wang X, Hallock L, Wolgemuth DJ. Aberrant distribution of junctional complex components in retinoic acid receptor alpha-deficient mice. Microsc Res Tech 2010; 73:583-96. [PMID: 19937743 PMCID: PMC2877760 DOI: 10.1002/jemt.20797] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Retinoic acid receptor alpha (RARalpha)-deficient mice are sterile, with abnormalities in the progression of spermatogenesis and spermiogenesis. In this study, we investigated whether defective retinoid signaling involved at least in part, disrupted cell-cell interactions. Hypertonic fixation approaches revealed defects in the integrity of the Sertoli-cell barrier in the tubules of RARalpha-deficient testes. Dye transfer experiments further revealed that coupling between cells from the basal to adluminal compartments was aberrant. There were also differences in the expression of several known retinoic acid (RA)-responsive genes encoding structural components of tight junctions and gap junctions. Immunostaining demonstrated a delay in the incorporation of zonula occludens (ZO-1), a peripheral component protein of tight junctions, into the Sertoli cell tight junctions. Markedly reduced expression of connexin-40 in mutant pachytene spermatocytes and round spermatids was found by in situ hybridization. An ectopic distribution of vimentin and disrupted cyclic expression of vimentin, which is usually tightly regulated during spermiogenesis, was found in RARalpha-deficient testes at all ages examined. Thus, the specific defects in spermiogenesis in RARalpha-deficient testes may correlate with a disrupted cyclic expression of RA-responsive structural components, including vimentin, a downregulation of connexin-40 in spermatogenic cells, and delayed assembly of ZO-1 into Sertoli cell tight junctions. Interestingly, bioinformatic analysis revealed that many genes that are components of tight junctions and gap junctions contained potential retinoic acid response element binding sites.
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Affiliation(s)
- Sanny S W Chung
- Department of Genetics and Development, Columbia University Medical Center, New York, NY 10032
- Department of Obstetrics and Gynecology, Columbia University Medical Center, New York, NY 10032
- The Institute of Human Nutrition, Columbia University Medical Center, New York, NY 10032
| | - Cindy Choi
- The Institute of Human Nutrition, Columbia University Medical Center, New York, NY 10032
| | - Xiangyuan Wang
- Department of Genetics and Development, Columbia University Medical Center, New York, NY 10032
| | - Loretta Hallock
- Department of Genetics and Development, Columbia University Medical Center, New York, NY 10032
| | - Debra J Wolgemuth
- Department of Genetics and Development, Columbia University Medical Center, New York, NY 10032
- Department of Obstetrics and Gynecology, Columbia University Medical Center, New York, NY 10032
- The Institute of Human Nutrition, Columbia University Medical Center, New York, NY 10032
- The Herbert Irving Comprehensive Cancer Center, Columbia University Medical Center, New York, NY 10032
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41
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Ong S, Tan C. Germline cyst formation and incomplete cytokinesis during Drosophila melanogaster oogenesis. Dev Biol 2010; 337:84-98. [DOI: 10.1016/j.ydbio.2009.10.018] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2009] [Revised: 10/10/2009] [Accepted: 10/12/2009] [Indexed: 11/16/2022]
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42
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Wu Z, Luby-Phelps K, Bugde A, Molyneux LA, Denard B, Li WH, Süel GM, Garbers DL. Capacity for stochastic self-renewal and differentiation in mammalian spermatogonial stem cells. ACTA ACUST UNITED AC 2009; 187:513-24. [PMID: 19948499 PMCID: PMC2779229 DOI: 10.1083/jcb.200907047] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Mammalian spermatogenesis is initiated and sustained by spermatogonial stem cells (SSCs) through self-renewal and differentiation. The basic question of whether SSCs have the potential to specify self-renewal and differentiation in a cell-autonomous manner has yet to be addressed. Here, we show that rat SSCs in ex vivo culture conditions consistently give rise to two distinct types of progeny: new SSCs and differentiating germ cells, even when they have been exposed to virtually identical microenvironments. Quantitative experimental measurements and mathematical modeling indicates that fate decision is stochastic, with constant probability. These results reveal an unexpected ability in a mammalian SSC to specify both self-renewal and differentiation through a self-directed mechanism, and further suggest that this mechanism operates according to stochastic principles. These findings provide an experimental basis for autonomous and stochastic fate choice as an alternative strategy for SSC fate bifurcation, which may also be relevant to other stem cell types.
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Affiliation(s)
- Zhuoru Wu
- Cecil H. and Ida Green Center for Reproductive Biology Sciences, Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.
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43
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Greenbaum MP, Iwamori N, Agno JE, Matzuk MM. Mouse TEX14 is required for embryonic germ cell intercellular bridges but not female fertility. Biol Reprod 2008; 80:449-57. [PMID: 19020301 DOI: 10.1095/biolreprod.108.070649] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
A conserved feature of germ cell cytokinesis is the formation of stable intercellular bridges between daughter cells. These intercellular bridges are seen in diverse species from Drosophila melanogaster to Homo sapiens and have been shown to have roles in communication of large numbers of germ cells. In testis expressed gene 14 (Tex14) knockout mice, intercellular bridges do not form during spermatogenesis, and male mice are sterile, demonstrating an essential role for intercellular bridges in postnatal spermatogenesis in mammals. Intercellular bridges also form between dividing germ cells in both male and female embryos. However, little is known about the formation or role of the embryonic intercellular bridges in mammals. In females, embryonic intercellular bridges have been proposed to have a role in development of the presumptive oocyte. Herein, we show that TEX14 is an essential component of male and female embryonic intercellular bridges. In addition, we demonstrate that mitotic kinesin-like protein 1 (MKLP1, official symbol KIF23), which we have discovered is a component of intercellular bridges during spermatogenesis, is also a component of male and female embryonic intercellular bridges. Germ cell intercellular bridges are readily identified by KIF23 immunofluorescence between the gonocytes and oogonia of control mice but are absent between germ cells of Tex14-null mice. Furthermore, by electron microscopy, intercellular bridges are present in all control newborn ovaries but are absent in the Tex14 knockout ovaries. Despite the absence of embryonic intercellular bridges in the Tex14-null mice, male mice initiate spermatogenesis, and female mice are fertile. Although fewer oocytes were present in Tex14-null neonatal ovaries, folliculogenesis was still active at 1 yr of age. Thus, while TEX14 and intercellular bridges have an essential role in postnatal spermatogenesis, they are not required in the embryo.
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Affiliation(s)
- Michael P Greenbaum
- Department of Pathology, Baylor College of Medicine, Houston, Texas 77030, USA
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44
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Chiarini-Garcia H, Meistrich ML. High-resolution light microscopic characterization of spermatogonia. Methods Mol Biol 2008; 450:95-107. [PMID: 18370053 DOI: 10.1007/978-1-60327-214-8_6] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
It is possible to distinguish the morphological features of the spermatogonial nuclei and nucleoli and to further identify their distinct generations using an appropriate method to fix whole testes via vascular perfusion with glutaraldehyde, postfixation by immersion in reduced osmium, embedding in araldite, and staining of semithin tissue sections. A well-trained individual can distinguish each of the spermatogonial types in rodents (A(undiferentiated), A(1), A(2), A(3), A(4), In, and B) using this tissue preparation technique based on their morphological details and without correlation with the stages of the epithelium cycle or other parameters. The possibility of distinguishing each spermatogonial type by their morphological characteristics allows a more accurate evaluation of their kinetics during the spermatogenic cycle. Moreover, the understanding of spermatogonial behavior is a means to elucidate the functional control of the spermatogenesis, which consequently allows the determination of their effects on the fertility of humans and other animals.
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Affiliation(s)
- Hélio Chiarini-Garcia
- Department of Morphology-ICB Federal University of Minas Gerais, Laboratory of Structural Biology and Reproduction, Belo Horizonte, MG, Brazil
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45
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Zheng H, Stratton CJ, Morozumi K, Jin J, Yanagimachi R, Yan W. Lack of Spem1 causes aberrant cytoplasm removal, sperm deformation, and male infertility. Proc Natl Acad Sci U S A 2007; 104:6852-7. [PMID: 17426145 PMCID: PMC1871874 DOI: 10.1073/pnas.0701669104] [Citation(s) in RCA: 110] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
We identified a previously uncharacterized gene, spermatid maturation 1 (Spem1), encoding a protein exclusively expressed in the cytoplasm of steps 14-16 elongated spermatids in the mouse testis. This protein contains no known functional domains and is highly conserved across mammalian species. Male mice deficient in Spem1 were completely infertile because of deformed sperm characterized by a bent head wrapped around by the neck and the middle piece of the tail. We show that lack of Spem1 causes failure of the cytoplasm to become loose and detach from the head and the neck region of the developing spermatozoa. Retained cytoplasmic components mechanically obstruct the straightening of the sperm head and the stretching of the growing tail, leading to the bending of the head in the neck, followed by the wrapping of the head by the neck or the middle piece of the sperm tail. Our study reveals that proper cytoplasm removal is a genetically regulated process requiring the participation of Spem1 and that lack of Spem1 causes sperm deformation and male infertility.
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Affiliation(s)
- Huili Zheng
- *Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, NV 89557; and
| | - Clifford J. Stratton
- *Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, NV 89557; and
| | - Kazuto Morozumi
- Institute for Biogenesis Research, John. A. Burns School of Medicine, University of Hawaii, Honolulu, HI 96822
| | - Jingling Jin
- *Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, NV 89557; and
| | - Ryuzo Yanagimachi
- Institute for Biogenesis Research, John. A. Burns School of Medicine, University of Hawaii, Honolulu, HI 96822
- To whom correspondence may be addressed at:
Department of Physiology and Cell Biology, University of Nevada School of Medicine, Anderson Biomedical Science Building 105C/111, 1664 North Virginia Street, MS 352, Reno, NV 89557. E-mail: or
| | - Wei Yan
- *Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, NV 89557; and
- To whom correspondence may be addressed at:
Department of Physiology and Cell Biology, University of Nevada School of Medicine, Anderson Biomedical Science Building 105C/111, 1664 North Virginia Street, MS 352, Reno, NV 89557. E-mail: or
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46
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Greenbaum MP, Ma L, Matzuk MM. Conversion of midbodies into germ cell intercellular bridges. Dev Biol 2007; 305:389-96. [PMID: 17383626 PMCID: PMC2717030 DOI: 10.1016/j.ydbio.2007.02.025] [Citation(s) in RCA: 89] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2006] [Revised: 02/14/2007] [Accepted: 02/15/2007] [Indexed: 10/23/2022]
Abstract
Whereas somatic cell cytokinesis resolves with abscission of the midbody, resulting in independent daughter cells, germ cell cytokinesis concludes with the formation of a stable intercellular bridge interconnecting daughter cells in a syncytium. While many proteins essential for abscission have been discovered, until recently, no proteins essential for mammalian germ cell intercellular bridge formation have been identified. Using TEX14 as a marker for the germ cell intercellular bridge, we show that TEX14 co-localizes with the centralspindlin complex, mitotic kinesin-like protein 1 (MKLP1) and male germ cell Rac GTPase-activating protein (MgcRacGAP) and converts these midbody matrix proteins into stable intercellular bridge components. In contrast, septins (SEPT) 2, 7 and 9 are transitional proteins in the newly forming bridge. In cultured somatic cells, TEX14 can localize to the midbody in the absence of other germ cell-specific factors, suggesting that TEX14 serves to bridge the somatic cytokinesis machinery to other germ cell proteins to form a stable intercellular bridge essential for male reproduction.
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Affiliation(s)
- Michael P. Greenbaum
- Department of Pathology, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030
- Department of Molecular and Human Genetics, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030
| | - Lang Ma
- Department of Pathology, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030
| | - Martin M. Matzuk
- Department of Pathology, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030
- Department of Molecular and Human Genetics, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030
- Department of Molecular and Cellular Biology, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030
- Corresponding author: Martin M. Matzuk, MD. PhD., The Stuart A. Wallace Chair and Professor, Department of Pathology, Baylor College of Medicine, One Baylor Plaza, Houston, TX, 77030, , Tel: 713-798-6451, FAX: 713-798-5833
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Espenes A, Harbitz I, Skogtvedt S, Fuglestveit R, Berg KA, Dick G, Krogenaes A, Tranulis MA. Dynamic expression of the prion-like protein Doppel in ovine testicular tissue. ACTA ACUST UNITED AC 2006; 29:400-8. [PMID: 16390495 DOI: 10.1111/j.1365-2605.2005.00618.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Transgenic knockout of the gene encoding the prion-like protein Doppel (Dpl) leads to male infertility in mice. The precise role of Dpl in male fertility is still unclear, but sperm from Dpl-deficient mice appear to be unable to undergo the normal acrosome reaction that is necessary to penetrate the zona pellucida of the ovum. We have investigated the expression pattern and some biochemical properties of Dpl in sheep testicular tissue and spermatozoa. Neither the Dpl protein nor its mRNA was detected in pre-pubertal sheep testis. This was in contrast to the findings in adult rams where both Dpl mRNA and protein were present. The molecular mass and glycosylation pattern of sheep Dpl were similar to that of mice Dpl. The Dpl protein was detected in the seminiferous epithelium during the two final (7 and 8) and the two initial (1 and 2) stages of the spermatogenic cycle in a characteristic pattern. In stage 8, an intense brim of granular Dpl-immunoreactivity associated with maturation phase spermatids was observed, while after the release of spermatozoa in stages 1 and 2, the Dpl-staining was disseminated more diffusely in the epithelium, reaching the basal lamina. From stage 3 to stage 6, Dpl-immunoreactivity could not be detected, indicating that the Dpl protein had disappeared between stages 2 and 3. Dpl was not detected on ejaculated spermatozoa. These patterns of staining indicate that Dpl is enriched in residual bodies, which are phagocytosed and destroyed by Sertoli cells after release of sperm into the lumen of the seminiferous tubule.
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Affiliation(s)
- Arild Espenes
- Department of Basic Sciences and Aquatic Medicine, Norwegian School of Veterinary Science, Oslo, Norway
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Aponte PM, van Bragt MPA, de Rooij DG, van Pelt AMM. Spermatogonial stem cells: characteristics and experimental possibilities. APMIS 2006; 113:727-42. [PMID: 16480445 DOI: 10.1111/j.1600-0463.2005.apm_302.x] [Citation(s) in RCA: 102] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The continuation of the spermatogenic process throughout life relies on a proper regulation of self-renewal and differentiation of the spermatogonial stem cells. These are single cells situated on the basal membrane of the seminiferous epithelium. Only 0.03% of all germ cells are spermatogonial stem cells. They are the only cell type that can repopulate and restore fertility to congenitally infertile recipient mice following transplantation. Although numerous expression markers have been helpful in isolating and enriching spermatogonial stem cells, such as expression of THY-1 and GFRalpha-1 and absence of c-kit, no specific marker for this cell type has yet been identified. Much effort has been put into developing a protocol for the maintenance of spermatogonial cells in vitro. Recently, coculture systems of testicular cells on various feeder cells have made it possible to culture spermatogonial stem cells for a long period of time, as was demonstrated by the transplantation assay. Even expansion of testicular cells, including the spermatogonial stem cells, has been achieved. In these culture systems, hormones and growth factors are investigated for their role in the process of proliferation of spermatogonial stem cells. At the moment the best culture system known still consists of a mixture of testicular cells with about 1.33% spermatogonial stem cells. Recently pure SV40 large T immortalized spermatogonial stem cell lines have been established. These c-kit-negative cell lines did not show any differentiation in vitro or in vivo. A telomerase immortalized c-kit-positive spermatogonial cell line has been established that was able to differentiate in vitro. Spermatocytes and even spermatids were formed. However, spermatogonial stem cell activity by means of the transplantation assay was not tested for this cell line. Both the primary long-term cultures and immortalized cell lines have represented a major step forward in investigating the regulation of spermatogonial self-renewal and differentiation, and will be useful for identifying specific molecular markers.
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Affiliation(s)
- Pedro M Aponte
- Department of Endocrinology, Faculty of Biology, Utrecht University, The Netherlands
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Greenbaum MP, Yan W, Wu MH, Lin YN, Agno JE, Sharma M, Braun RE, Rajkovic A, Matzuk MM. TEX14 is essential for intercellular bridges and fertility in male mice. Proc Natl Acad Sci U S A 2006; 103:4982-7. [PMID: 16549803 PMCID: PMC1458781 DOI: 10.1073/pnas.0505123103] [Citation(s) in RCA: 193] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Cytokinesis in somatic cells concludes with the formation of a midbody, which is abscised to form individual daughter cells. In contrast, germ cell cytokinesis results in a permanent intercellular bridge connecting the daughter cells through a large cytoplasmic channel. During spermatogenesis, proposed roles for the intercellular bridge include germ cell communication, synchronization, and chromosome dosage compensation in haploid cells. Although several essential components of the midbody have recently been identified, essential components of the vertebrate germ cell intercellular bridge have until now not been described. Herein, we show that testis-expressed gene 14 (TEX14) is a novel protein that localizes to germ cell intercellular bridges. In the absence of TEX14, intercellular bridges are not observed by using electron microscopy and other markers. Spermatogenesis in Tex14(-/-) mice progresses through the transit amplification of diploid spermatogonia and the expression of early meiotic markers but halts before the completion of the first meiotic division. Thus, TEX14 is required for intercellular bridges in vertebrate germ cells, and these studies provide evidence that the intercellular bridge is essential for spermatogenesis and fertility.
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Affiliation(s)
| | - Wei Yan
- Departments of *Pathology
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, NV 89557; and
| | | | - Yi-Nan Lin
- Departments of *Pathology
- Molecular and Cellular Biology, and
| | | | - Manju Sharma
- **Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA 98195
| | - Robert E. Braun
- **Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA 98195
| | - Aleksandar Rajkovic
- Obstetrics and Gynecology, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030
| | - Martin M. Matzuk
- Departments of *Pathology
- Molecular and Human Genetics
- Molecular and Cellular Biology, and
- To whom correspondence should be addressed. E-mail:
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50
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Tran N, Servos G, Haider SG. Ultrastructure of cell contacts of fetal and adult Leydig cells in the rat: a systematic study from birth to senium. ACTA ACUST UNITED AC 2006; 211:273-82. [PMID: 16450174 DOI: 10.1007/s00429-006-0079-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/09/2006] [Indexed: 10/25/2022]
Abstract
Differentiation, development, and function of Leydig cells in the testis are regulated also by macrophages, vascular endothelial cells, and peritubular cells in the testis. The aim of the present study was to investigate the possible morphological substrates for communication between these cells. The cell contacts between adjacent Leydig cells, and between Leydig cells and other interstitial cells were studied electron microscopically in the rat testis of various age groups from birth to senium. Intercellular bridges with continuous cytoplasm were observed between fetal Leydig cells (FLCs) in the early postnatal period. Gap junctions were present in nearly every age group. A structural diversity as well as an increased occurrence of gap junctions with the maturity of the Leydig cells was noted. Coated pits were observed initially on pnd 30. From pnd 50 onwards, macrophages and Leydig cells were attached very closely to each other, when the cell processes of Leydig cells protruded either into the coated pits or into the deep invaginations of macrophages. To conclude, this is the first report on the presence of intercellular bridges between FLCs suggesting a possible functional synchronization of interconnected Leydig cells. The cell contacts observed here are possibly required for a precise communication between the Leydig cells and other interstitial cells.
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Affiliation(s)
- Nicole Tran
- Institute of Anatomy II, Heinrich Heine University, Moorenstr. 5, 40225, Düsseldorf, Germany
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