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Gao S, Chen Z, Wu X, Wang L, Bu T, Li L, Li X, Yun D, Sun F, Cheng CY. Perfluorooctane sulfonate-induced Sertoli cell injury through c-Jun N-terminal kinase: a study by RNA-Seq. Am J Physiol Cell Physiol 2024; 327:C291-C309. [PMID: 38826136 DOI: 10.1152/ajpcell.00212.2024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2024] [Revised: 05/14/2024] [Accepted: 05/27/2024] [Indexed: 06/04/2024]
Abstract
Per- and polyfluoroalkyl substances (PFASs) are a family of "forever chemicals" including perfluorooctane sulfonate (PFOS). These toxic chemicals do not break down in the environment or in our bodies. In the human body, PFOS and perfluoroctanoic acid (PFOA) have a half-life (T1/2) of about 4-5 yr so low daily consumption of these chemicals can accumulate in the human body to a harmful level over a long period. Although the use of PFOS in consumer products was banned in the United States in 2022/2023, this forever chemical remains detectable in our tap water and food products. Every American tested has a high level of PFAS in their blood (https://cleanwater.org/pfas-forever-chemicals). In this report, we used a Sertoli cell blood-testis barrier (BTB) model with primary Sertoli cells cultured in vitro with an established functional tight junction (TJ)-permeability barrier that mimicked the BTB in vivo. Treatment of Sertoli cells with PFOS was found to perturb the TJ-barrier, which was the result of cytoskeletal disruption across the cell cytoplasm, disrupting actin and microtubule polymerization. These changes thus affected the proper localization of BTB-associated proteins at the BTB. Using RNA-Seq transcriptome profiling, bioinformatics analysis, and pertinent biochemical and cell biology techniques, it was discovered that PFOS -induced Sertoli cell toxicity through the c-Jun N-terminal kinase (JNK; also known as stress-activated protein kinase, SAPK) and its phosphorylated/active form p-JNK signaling pathway. More importantly, KB-R7943 mesylate (KB), a JNK/p-JNK activator, was capable of blocking PFOS-induced Sertoli cell injury, supporting the notion that PFOS-induced cell injury can possibly be therapeutically managed.NEW & NOTEWORTHY PFOS induces Sertoli cell injury, including disruption of the 1) blood-testis barrier function and 2) cytoskeletal organization, which, in turn, impedes male reproductive function. These changes are mediated by JNK/p-JNK signaling pathway. However, the use of KB-R7943, a JNK/p-JNK activator was capable of blocking PFOS-induced Sertoli cell injury, supporting the possibility of therapeutically managing PFOS-induced reproductive dysfunction.
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Affiliation(s)
- Sheng Gao
- Institute of Reproductive Medicine, Medical School of Nantong University, Nantong, People's Republic of China
| | - Zifeng Chen
- Institute of Reproductive Medicine, Medical School of Nantong University, Nantong, People's Republic of China
| | - Xiaolong Wu
- Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, People's Republic of China
| | - Lingling Wang
- Institute of Reproductive Medicine, Medical School of Nantong University, Nantong, People's Republic of China
| | - Tiao Bu
- Institute of Reproductive Medicine, Medical School of Nantong University, Nantong, People's Republic of China
| | - Linxi Li
- The Second Affiliated Hospital and Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, People's Republic of China
| | - Xinyao Li
- Institute of Reproductive Medicine, Medical School of Nantong University, Nantong, People's Republic of China
| | - Damin Yun
- Institute of Reproductive Medicine, Medical School of Nantong University, Nantong, People's Republic of China
| | - Fei Sun
- Institute of Reproductive Medicine, Medical School of Nantong University, Nantong, People's Republic of China
| | - C Yan Cheng
- Institute of Reproductive Medicine, Medical School of Nantong University, Nantong, People's Republic of China
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Wang Y, Chembazhi UV, Yee D, Chen S, Ji J, Wang Y, Nguyen KL, Lin P, Ratti A, Hess R, Qiao H, Ko C, Yang J, Kalsotra A, Mei W. PTBP1 mediates Sertoli cell actin cytoskeleton organization by regulating alternative splicing of actin regulators. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.06.12.598725. [PMID: 38915624 PMCID: PMC11195235 DOI: 10.1101/2024.06.12.598725] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/26/2024]
Abstract
Spermatogenesis is a biological process within the testis that produces haploid spermatozoa for the continuity of species. Sertoli cells are somatic cells in the seminiferous epithelium that orchestrate spermatogenesis. Cyclic reorganization of Sertoli cell actin cytoskeleton is vital for spermatogenesis, but the underlying mechanism remains largely unclear. Here, we report that RNA-binding protein PTBP1 controls Sertoli cell actin cytoskeleton reorganization by programming alternative splicing of actin cytoskeleton regulators. This splicing control enables ectoplasmic specializations, the actin-based adhesion junctions, to maintain the blood-testis barrier and support spermatid transport and transformation. Particularly, we show that PTBP1 promotes actin bundle formation by repressing the inclusion of exon 14 of Tnik, a kinase present at the ectoplasmic specialization. Our results thus reveal a novel mechanism wherein Sertoli cell actin cytoskeleton dynamics is controlled post-transcriptionally by utilizing functionally distinct isoforms of actin regulatory proteins, and PTBP1 is a critical regulatory factor in generating such isoforms.
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Affiliation(s)
- Yuexi Wang
- Department of Comparative Biosciences, College of Veterinary Medicine, University of Illinois Urbana-Champaign, Urbana, IL, USA
- These authors contributed equally to the work
| | - Ullas Valiya Chembazhi
- Department of Biochemistry, The School of Molecular and Cellular Biology, College of Liberal Arts & Sciences, University of Illinois Urbana-Champaign, Urbana, IL, USA
- Current address: Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- These authors contributed equally to the work
| | - Danielle Yee
- Department of Comparative Biosciences, College of Veterinary Medicine, University of Illinois Urbana-Champaign, Urbana, IL, USA
- Current address: University of Maryland School of Medicine, Baltimore, MD, USA
| | - Sijie Chen
- Department of Comparative Biosciences, College of Veterinary Medicine, University of Illinois Urbana-Champaign, Urbana, IL, USA
| | - Jie Ji
- Department of Comparative Biosciences, College of Veterinary Medicine, University of Illinois Urbana-Champaign, Urbana, IL, USA
- Current address: Department of Integrative Biology & Physiology, University of California, Los Angeles, Los Angeles, CA, USA
| | - Yujie Wang
- Department of Comparative Biosciences, College of Veterinary Medicine, University of Illinois Urbana-Champaign, Urbana, IL, USA
- Current address: College of Arts and Science, Vanderbilt University, Nashville, TN, USA
| | - Ka Lam Nguyen
- Department of Comparative Biosciences, College of Veterinary Medicine, University of Illinois Urbana-Champaign, Urbana, IL, USA
| | - PoChing Lin
- Department of Comparative Biosciences, College of Veterinary Medicine, University of Illinois Urbana-Champaign, Urbana, IL, USA
| | - Antonia Ratti
- Department of Medical Biotechnology and Translational Medicine, Universita degli studi di Milano, Via Fratelli Cervi 93, 20090, Segrate, Milan, Italy
| | - Rex Hess
- Department of Comparative Biosciences, College of Veterinary Medicine, University of Illinois Urbana-Champaign, Urbana, IL, USA
| | - Huanyu Qiao
- Department of Comparative Biosciences, College of Veterinary Medicine, University of Illinois Urbana-Champaign, Urbana, IL, USA
| | - CheMyong Ko
- Department of Comparative Biosciences, College of Veterinary Medicine, University of Illinois Urbana-Champaign, Urbana, IL, USA
| | - Jing Yang
- Department of Comparative Biosciences, College of Veterinary Medicine, University of Illinois Urbana-Champaign, Urbana, IL, USA
| | - Auinash Kalsotra
- Department of Biochemistry, The School of Molecular and Cellular Biology, College of Liberal Arts & Sciences, University of Illinois Urbana-Champaign, Urbana, IL, USA
- Cancer Center at Illinois, University of Illinois Urbana-Champaign, Urbana, IL, USA
- Carl R. Woese Institute for Genomic Biology, University of Illinois Urbana-Champaign, Urbana, IL, USA
- Division of Nutrition Sciences, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Wenyan Mei
- Department of Comparative Biosciences, College of Veterinary Medicine, University of Illinois Urbana-Champaign, Urbana, IL, USA
- Cancer Center at Illinois, University of Illinois Urbana-Champaign, Urbana, IL, USA
- Carl R. Woese Institute for Genomic Biology, University of Illinois Urbana-Champaign, Urbana, IL, USA
- Division of Nutrition Sciences, University of Illinois at Urbana-Champaign, Urbana, IL, USA
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3
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Peña-Corona SI, Vargas-Estrada D, Juárez-Rodríguez I, Retana-Márquez S, Mendoza-Rodríguez CA. Bisphenols as promoters of the dysregulation of cellular junction proteins of the blood-testis barrier in experimental animals: A systematic review of the literature. J Biochem Mol Toxicol 2023; 37:e23416. [PMID: 37352109 DOI: 10.1002/jbt.23416] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2022] [Revised: 04/03/2023] [Accepted: 06/08/2023] [Indexed: 06/25/2023]
Abstract
Daily, people are exposed to chemicals and environmental compounds such as bisphenols (BPs). These substances are present in more than 80% of human fluids. Human exposure to BPs is associated with male reproductive health disorders. Some of the main targets of BPs are intercellular junction proteins of the blood-testis barrier (BTB) in Sertoli cells because BPs alter the expression or induce aberrant localization of these proteins. In this systematic review, we explore the effects of BP exposure on the expression of BTB junction proteins and the characteristics of in vivo studies to identify potential gaps and priorities for future research. To this end, we conducted a systematic review of articles. Thirteen studies met our inclusion criteria. In most studies, animals treated with bisphenol-A (BPA) showed decreased occludin expression at all tested doses. However, bisphenol-AF treatment did not alter occludin expression. Cx43, ZO-1, β-catenin, nectin-3, cortactin, paladin, and claudin-11 expression also decreased in some tested doses of BP, while N-cadherin and FAK expression increased. BP treatment did not alter the expression of α and γ catenin, E-cadherin, JAM-A, and Arp 3. However, the expression of all these proteins was altered when BPA was administered to neonatal rodents in microgram doses. The results show significant heterogeneity between studies. Thus, it is necessary to perform more research to characterize the changes in BTB protein expression induced by BPs in animals to highlight future research directions that can inform the evaluation of risk of toxicity in humans.
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Affiliation(s)
- Sheila I Peña-Corona
- Departamento de Biología, Facultad de Química, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Dinorah Vargas-Estrada
- Departamento de Fisiología y Farmacología, Facultad de Medicina Veterinaria y Zootecnia, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Ivan Juárez-Rodríguez
- Departamento de Medicina Preventiva y Salud Pública, Facultad de Medicina Veterinaria y Zootecnia, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Socorro Retana-Márquez
- Departamento Biología de la Reproducción, Universidad Autónoma Metropolitana-Iztapalapa, Mexico City, Mexico
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Pasquariello R, Anipchenko P, Pennarossa G, Crociati M, Zerani M, Brevini TA, Gandolfi F, Maranesi M. Carotenoids in female and male reproduction. PHYTOCHEMISTRY 2022; 204:113459. [PMID: 36183866 DOI: 10.1016/j.phytochem.2022.113459] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Revised: 09/21/2022] [Accepted: 09/26/2022] [Indexed: 06/16/2023]
Abstract
Carotenoids are among the best-known pigments in nature, confer color to plants and animals, and are mainly derived from photosynthetic bacteria, fungi, algae, plants. Mammals cannot synthesize carotenoids. Carotenoids' source is only alimentary and after their assumption, they are mainly converted in retinal, retinol and retinoic acid, collectively known also as pro-vitamins and vitamin A, which play an essential role in tissue growth and regulate different aspects of the reproductive functions. However, their mechanisms of action and potential therapeutic effects are still unclear. This review aims to clarify the role of carotenoids in the male and female reproductive functions in species of veterinary interest. In female, carotenoids and their derivatives regulate not only folliculogenesis and oogenesis but also steroidogenesis. Moreover, they improve fertility by decreasing the risk of embryonic mortality. In male, retinol and retinoic acids activate molecular pathways related to spermatogenesis. Deficiencies of these vitamins have been correlated with degeneration of testis parenchyma with consequent absence of the mature sperm. Carotenoids have also been considered anti-antioxidants as they ameliorate the effect of free radicals. The mechanisms of action seem to be exerted by activating Kit and Stra8 pathways in both female and male. In conclusion, carotenoids have potentially beneficial effects for ameliorating ovarian and testes function.
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Affiliation(s)
- Rolando Pasquariello
- Department of Agricultural and Environmental Sciences - Production, Landscape, Agroenergy, Università Degli Studi di Milano, 20133, Milan, Italy
| | - Polina Anipchenko
- Department of Veterinary Medicine, University of Perugia, Via S. Costanzo 4, 06126, Perugia, Italy
| | - Georgia Pennarossa
- Laboratory of Biomedical Embryology, Department of Veterinary Medicine and Animal Sciences, Università Degli Studi di Milano, 26900, Lodi, Italy.
| | - Martina Crociati
- Department of Veterinary Medicine, University of Perugia, Via S. Costanzo 4, 06126, Perugia, Italy; Centre for Perinatal and Reproductive Medicine, University of Perugia, 06129, Perugia, Italy
| | - Massimo Zerani
- Department of Veterinary Medicine, University of Perugia, Via S. Costanzo 4, 06126, Perugia, Italy
| | - Tiziana Al Brevini
- Laboratory of Biomedical Embryology, Department of Veterinary Medicine and Animal Sciences, Università Degli Studi di Milano, 26900, Lodi, Italy
| | - Fulvio Gandolfi
- Department of Agricultural and Environmental Sciences - Production, Landscape, Agroenergy, Università Degli Studi di Milano, 20133, Milan, Italy
| | - Margherita Maranesi
- Department of Veterinary Medicine, University of Perugia, Via S. Costanzo 4, 06126, Perugia, Italy
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Fu Y, Wei Y, Zhou Y, Wu H, Hong Y, Long C, Wang J, Wu Y, Wu S, Shen L, Wei G. Wnt5a Regulates Junctional Function of Sertoli cells Through PCP-mediated Effects on mTORC1 and mTORC2. Endocrinology 2021; 162:6334711. [PMID: 34338758 DOI: 10.1210/endocr/bqab149] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/19/2021] [Indexed: 12/14/2022]
Abstract
The blood-testis barrier (BTB) and apical ectoplasmic specialization (ES), which are synchronized through the crosstalk of Sertoli cells and Sertoli germ cells, are required for spermatogenesis and sperm release. Here, we show that Wnt5a, a noncanonical Wnt signaling pathway ligand, is predominately expressed in both the BTB and apical ES and has a specific expression pattern during the seminiferous epithelium cycle. We employed siRNA to knockdown Wnt5a expression in testis and Sertoli cells, and then identified elongated spermatids that lost their polarity and were embedded in the seminiferous epithelium. Moreover, phagosomes were found near the tubule lumen. These defects were due to BTB and apical ES disruption. We also verified that the expression level and/or location of BTB-associated proteins, actin binding proteins (ABPs), and F-actin was changed after Wnt5a knockdown in vivo and in vitro. Additionally, we demonstrated that Wnt5a regulated actin dynamics through Ror2-mediated mTORC1 and mTORC2. This study clarified the molecular mechanism of Wnt5a in Sertoli cell junctions through the planar cell polarity (PCP) signaling pathway. Our findings could provide an experimental basis for the clinical diagnosis and treatment of male infertility caused by Sertoli cell junction impairment.
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Affiliation(s)
- Yan Fu
- Department of Urology, Children's Hospital of Chongqing Medical University, Chongqing, 400014, PR China
- Pediatric Research Institute, Children's Hospital of Chongqing Medical University, Chongqing, 400014, PR China
- Chongqing Key Laboratory of Children Urogenital Development and Tissue Engineering; Chongqing Key Laboratory of Pediatrics; Ministry of Education Key Laboratory of Child Development and Disorders; National Clinical Research Center for Child Health and Disorders; China International Science and Technology Cooperation base of Child development and Critical Disorders, Children's Hospital of Chongqing Medical University, Chongqing, 400014, PR China
| | - Yuexin Wei
- Department of Urology, Children's Hospital of Chongqing Medical University, Chongqing, 400014, PR China
- Pediatric Research Institute, Children's Hospital of Chongqing Medical University, Chongqing, 400014, PR China
- Chongqing Key Laboratory of Children Urogenital Development and Tissue Engineering; Chongqing Key Laboratory of Pediatrics; Ministry of Education Key Laboratory of Child Development and Disorders; National Clinical Research Center for Child Health and Disorders; China International Science and Technology Cooperation base of Child development and Critical Disorders, Children's Hospital of Chongqing Medical University, Chongqing, 400014, PR China
| | - Yu Zhou
- Department of Urology, Children's Hospital of Chongqing Medical University, Chongqing, 400014, PR China
- Pediatric Research Institute, Children's Hospital of Chongqing Medical University, Chongqing, 400014, PR China
- Chongqing Key Laboratory of Children Urogenital Development and Tissue Engineering; Chongqing Key Laboratory of Pediatrics; Ministry of Education Key Laboratory of Child Development and Disorders; National Clinical Research Center for Child Health and Disorders; China International Science and Technology Cooperation base of Child development and Critical Disorders, Children's Hospital of Chongqing Medical University, Chongqing, 400014, PR China
| | - Huan Wu
- Department of Urology, Children's Hospital of Chongqing Medical University, Chongqing, 400014, PR China
- Pediatric Research Institute, Children's Hospital of Chongqing Medical University, Chongqing, 400014, PR China
- Chongqing Key Laboratory of Children Urogenital Development and Tissue Engineering; Chongqing Key Laboratory of Pediatrics; Ministry of Education Key Laboratory of Child Development and Disorders; National Clinical Research Center for Child Health and Disorders; China International Science and Technology Cooperation base of Child development and Critical Disorders, Children's Hospital of Chongqing Medical University, Chongqing, 400014, PR China
| | - Yifan Hong
- Department of Urology, Children's Hospital of Chongqing Medical University, Chongqing, 400014, PR China
- Pediatric Research Institute, Children's Hospital of Chongqing Medical University, Chongqing, 400014, PR China
- Chongqing Key Laboratory of Children Urogenital Development and Tissue Engineering; Chongqing Key Laboratory of Pediatrics; Ministry of Education Key Laboratory of Child Development and Disorders; National Clinical Research Center for Child Health and Disorders; China International Science and Technology Cooperation base of Child development and Critical Disorders, Children's Hospital of Chongqing Medical University, Chongqing, 400014, PR China
| | - Chunlan Long
- Pediatric Research Institute, Children's Hospital of Chongqing Medical University, Chongqing, 400014, PR China
- Chongqing Key Laboratory of Children Urogenital Development and Tissue Engineering; Chongqing Key Laboratory of Pediatrics; Ministry of Education Key Laboratory of Child Development and Disorders; National Clinical Research Center for Child Health and Disorders; China International Science and Technology Cooperation base of Child development and Critical Disorders, Children's Hospital of Chongqing Medical University, Chongqing, 400014, PR China
| | - Junke Wang
- Department of Urology, Children's Hospital of Chongqing Medical University, Chongqing, 400014, PR China
- Pediatric Research Institute, Children's Hospital of Chongqing Medical University, Chongqing, 400014, PR China
- Chongqing Key Laboratory of Children Urogenital Development and Tissue Engineering; Chongqing Key Laboratory of Pediatrics; Ministry of Education Key Laboratory of Child Development and Disorders; National Clinical Research Center for Child Health and Disorders; China International Science and Technology Cooperation base of Child development and Critical Disorders, Children's Hospital of Chongqing Medical University, Chongqing, 400014, PR China
| | - Yuhao Wu
- Department of Urology, Children's Hospital of Chongqing Medical University, Chongqing, 400014, PR China
- Pediatric Research Institute, Children's Hospital of Chongqing Medical University, Chongqing, 400014, PR China
- Chongqing Key Laboratory of Children Urogenital Development and Tissue Engineering; Chongqing Key Laboratory of Pediatrics; Ministry of Education Key Laboratory of Child Development and Disorders; National Clinical Research Center for Child Health and Disorders; China International Science and Technology Cooperation base of Child development and Critical Disorders, Children's Hospital of Chongqing Medical University, Chongqing, 400014, PR China
| | - Shengde Wu
- Department of Urology, Children's Hospital of Chongqing Medical University, Chongqing, 400014, PR China
- Chongqing Key Laboratory of Children Urogenital Development and Tissue Engineering; Chongqing Key Laboratory of Pediatrics; Ministry of Education Key Laboratory of Child Development and Disorders; National Clinical Research Center for Child Health and Disorders; China International Science and Technology Cooperation base of Child development and Critical Disorders, Children's Hospital of Chongqing Medical University, Chongqing, 400014, PR China
| | - Lianju Shen
- Pediatric Research Institute, Children's Hospital of Chongqing Medical University, Chongqing, 400014, PR China
- Chongqing Key Laboratory of Children Urogenital Development and Tissue Engineering; Chongqing Key Laboratory of Pediatrics; Ministry of Education Key Laboratory of Child Development and Disorders; National Clinical Research Center for Child Health and Disorders; China International Science and Technology Cooperation base of Child development and Critical Disorders, Children's Hospital of Chongqing Medical University, Chongqing, 400014, PR China
| | - Guanghui Wei
- Department of Urology, Children's Hospital of Chongqing Medical University, Chongqing, 400014, PR China
- Chongqing Key Laboratory of Children Urogenital Development and Tissue Engineering; Chongqing Key Laboratory of Pediatrics; Ministry of Education Key Laboratory of Child Development and Disorders; National Clinical Research Center for Child Health and Disorders; China International Science and Technology Cooperation base of Child development and Critical Disorders, Children's Hospital of Chongqing Medical University, Chongqing, 400014, PR China
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6
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Chen H, Jiang Y, Mruk DD, Cheng CY. Spermiation: Insights from Studies on the Adjudin Model. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021; 1288:241-254. [PMID: 34453740 DOI: 10.1007/978-3-030-77779-1_12] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Spermatogenesis is comprised of a series of cellular events that lead to the generation of haploid sperm. These events include self-renewal of spermatogonial stem cells (SSC), proliferation of spermatogonia by mitosis, differentiation of spermatogonia and spermatocytes, generation of haploid spermatids via meiosis I/II, and spermiogenesis. Spermiogenesis consists of a series of morphological events in which spermatids are being transported across the apical compartment of the seminiferous epithelium while maturing into spermatozoa, which include condensation of the genetic materials, biogenesis of acrosome, packaging of the mitocondria into the mid-piece, and elongation of the sperm tail. However, the biology of spermiation remains poorly understood. In this review, we provide in-depth analysis based on the use of bioinformatics tools and an animal model that mimics spermiation through treatment of adult rats with adjudin, a non-hormonal male contraceptive known to induce extensive germ cell exfoliation across the seminiferous epithelium, but nost notably elongating/elongated spermatids. These analyses have shed insightful information regaridng the biology of spermiation.
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Affiliation(s)
- Haiqi Chen
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, NY, USA
| | - Yu Jiang
- College of Pharmacy, University of Iowa, Iowa City, IA, USA
| | - Dolores D Mruk
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, NY, USA
| | - C Yan Cheng
- Sir Run Run Shaw Hospital (SRRSH), Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.
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7
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Wu S, Lv L, Li L, Wang L, Mao B, Li J, Shen X, Ge R, Wong CKC, Sun F, Cheng CY. KIF15 supports spermatogenesis via its effects on Sertoli cell microtubule, actin, vimentin, and septin cytoskeletons. Endocrinology 2021; 162:6102572. [PMID: 33453102 PMCID: PMC7883770 DOI: 10.1210/endocr/bqab010] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Indexed: 01/09/2023]
Abstract
Throughout spermatogenesis, cellular cargoes including haploid spermatids are required to be transported across the seminiferous epithelium, either toward the microtubule (MT) plus (+) end near the basement membrane at stage V, or to the MT minus (-) end near the tubule lumen at stages VI to VIII of the epithelial cycle. Furthermore, preleptotene spermatocytes, differentiated from type B spermatogonia, are transported across the Sertoli cell blood-testis barrier (BTB) to enter the adluminal compartment. Few studies, however, have been conducted to explore the function of MT-dependent motor proteins to support spermatid transport during spermiogenesis. Herein, we examined the role of MT-dependent and microtubule plus (+) end-directed motor protein kinesin 15 (KIF15) in the testis. KIF15 displayed a stage-specific expression across the seminiferous epithelium, associated with MTs, and appeared as aggregates on the MT tracks that aligned perpendicular to the basement membrane and laid across the entire epithelium. KIF15 also tightly associated with apical ectoplasmic specialization, displaying strict stage-specific distribution, apparently to support spermatid transport across the epithelium. We used a loss-of-function approach by RNAi to examine the role of KIF15 in Sertoli cell epithelium in vitro to examine its role in cytoskeletal-dependent Sertoli cell function. It was noted that KIF15 knockdown by RNAi that reduced KIF15 expression by ~70% in Sertoli cells with an established functional tight junction barrier impeded the barrier function. This effect was mediated through remarkable changes in the cytoskeletal organization of MTs, but also actin-, vimentin-, and septin-based cytoskeletons, illustrating that KIF15 exerts its regulatory effects well beyond microtubules.
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Affiliation(s)
- Siwen Wu
- The Second Affiliated Hospital and Yuying Children’s Hospital, Department of Anesthesiology, Wenzhou Medical University, Wenzhou, Zhejiang, China
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, NY, USA
| | - Lixiu Lv
- The Second Affiliated Hospital and Yuying Children’s Hospital, Department of Anesthesiology, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Linxi Li
- The Second Affiliated Hospital and Yuying Children’s Hospital, Department of Anesthesiology, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Lingling Wang
- Institute of Reproductive Medicine, Nantong University School of Medicine, Nantong, Jiangsu, China
| | - Baiping Mao
- The Second Affiliated Hospital and Yuying Children’s Hospital, Department of Anesthesiology, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Jun Li
- The Second Affiliated Hospital and Yuying Children’s Hospital, Department of Anesthesiology, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Xian Shen
- The Second Affiliated Hospital and Yuying Children’s Hospital, Department of Anesthesiology, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Renshan Ge
- The Second Affiliated Hospital and Yuying Children’s Hospital, Department of Anesthesiology, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Chris K C Wong
- Croucher Institute for Environmental Sciences, Department of Biology, Hong Kong Baptist University, Kowloon, Hong Kong, China
| | - Fei Sun
- Institute of Reproductive Medicine, Nantong University School of Medicine, Nantong, Jiangsu, China
| | - C Yan Cheng
- The Second Affiliated Hospital and Yuying Children’s Hospital, Department of Anesthesiology, Wenzhou Medical University, Wenzhou, Zhejiang, China
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, NY, USA
- Institute of Reproductive Medicine, Nantong University School of Medicine, Nantong, Jiangsu, China
- Correspondence: C. Yan Cheng, Ph.D., Senior Scientist, The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, 1230 York Ave, New York, NY 10065, USA.
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8
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Xu D, Wang J, Ma Y, Ding J, Han X, Chen Y. Microcystin-leucine-arginine induces apical ectoplasmic specialization disassembly. CHEMOSPHERE 2021; 264:128440. [PMID: 33002802 DOI: 10.1016/j.chemosphere.2020.128440] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2020] [Revised: 09/13/2020] [Accepted: 09/23/2020] [Indexed: 06/11/2023]
Abstract
Microcystin-leucine-arginine (MC-LR) has been identified to be a hazardous material to cause hepatotoxicity. In this study, mice were exposed to MC-LR dissolved in drinking water at doses of 1, 10, 20 and 30 μg/L for 90 and 180 days, respectively. We validated MC-LR accelerated spermatid exfoliation and caused large vacuoles in testes, reducing sperm count and increasing percentage of morphologically abnormal sperm. Furthermore, we found MC-LR induced the apical ectoplasmic specialization (ES) disassembly by disrupting F-actin organization. Further studies identified that downregulation of Palladin, the actin crosslinking protein, might be associated with disassembly of the apical ES in mice testis following MC-LR exposure. We also confirmed that MC-LR disrupted the interaction between Palladin and other actin-related proteins and thus impeded the F-actin organization. Additionally, we found that autophagy initiated by AMPK/ULK1 signaling pathway mediated the degradation of Palladin in Sertoli cells challenged with MC-LR. Following exposure to MC-LR, reduced PP2A activity and upregulated expression of LKB1 and CAMKK2 could activate AMPK. In conclusion, these results revealed MC-LR induced the degradation of Palladin via AMPK/ULK1-mediated autophagy, which might result in the apical ES disorder and spermatid exfoliation from spermatogenic epithelium. Our work may provide a new perspective to understand MC-LR-induced male infertility.
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Affiliation(s)
- Dihui Xu
- Immunology and Reproduction Biology Laboratory & State Key Laboratory of Analytical Chemistry for Life Science, Medical School, Nanjing University, Nanjing, 210093, China; Jiangsu Key Laboratory of Molecular Medicine, Nanjing University, Nanjing, 210093, China.
| | - Jing Wang
- Immunology and Reproduction Biology Laboratory & State Key Laboratory of Analytical Chemistry for Life Science, Medical School, Nanjing University, Nanjing, 210093, China; Jiangsu Key Laboratory of Molecular Medicine, Nanjing University, Nanjing, 210093, China.
| | - Yuhan Ma
- Immunology and Reproduction Biology Laboratory & State Key Laboratory of Analytical Chemistry for Life Science, Medical School, Nanjing University, Nanjing, 210093, China; Jiangsu Key Laboratory of Molecular Medicine, Nanjing University, Nanjing, 210093, China.
| | - Jie Ding
- Immunology and Reproduction Biology Laboratory & State Key Laboratory of Analytical Chemistry for Life Science, Medical School, Nanjing University, Nanjing, 210093, China; Jiangsu Key Laboratory of Molecular Medicine, Nanjing University, Nanjing, 210093, China.
| | - Xiaodong Han
- Immunology and Reproduction Biology Laboratory & State Key Laboratory of Analytical Chemistry for Life Science, Medical School, Nanjing University, Nanjing, 210093, China; Jiangsu Key Laboratory of Molecular Medicine, Nanjing University, Nanjing, 210093, China.
| | - Yabing Chen
- Immunology and Reproduction Biology Laboratory & State Key Laboratory of Analytical Chemistry for Life Science, Medical School, Nanjing University, Nanjing, 210093, China; Jiangsu Key Laboratory of Molecular Medicine, Nanjing University, Nanjing, 210093, China.
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9
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Kurohmaru M, Matsui T, Igarashi H, Hattori S, Hayashi Y. Postnatal testicular development and actin appearance in the seminiferous epithelium of the Habu, Trimeresurus flavoviridis. Anat Histol Embryol 2020; 50:417-421. [PMID: 33105047 DOI: 10.1111/ahe.12628] [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: 05/10/2020] [Revised: 06/22/2020] [Accepted: 10/08/2020] [Indexed: 11/29/2022]
Abstract
The postnatal testicular development and actin distribution in the seminiferous epithelium were examined by light microscopy, using the testes of the Habu (Trimeresurus flavoviridis; snake) from 0-year-old to 3-year-old. At 0-year-old (about 1 month after birth), the testis was quite small in size, and the seminiferous epithelium was composed of only Sertoli cells and large spermatogonia. Actin immunoreactivity was observed in the peritubular myoid cells, but could not be detected in the seminiferous epithelium. At 1-year-old (about 10 months after birth), the testicular size increased to a great degree. In the seminiferous epithelium, spermatocytes newly appeared. Actin could still not be detected in the seminiferous epithelium. At 2-year-old (about 1 year and 10 months after birth), the testes continued to develop in size. In the seminiferous epithelium, elongate spermatids and round spermatids were frequently seen, in addition to Sertoli cells, spermatogonia and spermatocytes. Thus, active spermatogenesis was clearly recognized at this age. Moreover, the actin distribution in the seminiferous epithelium was observed at the site between Sertoli cells and spermatids, as well as that at adult stage. The immunoreactivity of actin in the peritubular myoid cells gradually increased from 0-year-old to 2-year-old. Conclusively, it seems likely that spermatogenesis in the Habu initiates at 2-year-old, accompanying with the appearance of actin in the seminiferous epithelium.
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Affiliation(s)
- Masamichi Kurohmaru
- Laboratory of Veterinary Anatomy, Department of Veterinary Medicine, Okayama University of Science, Imabari, Japan.,Department of Veterinary Anatomy, The University of Tokyo, Tokyo, Japan
| | - Toshiyasu Matsui
- Laboratory of Veterinary Anatomy, Department of Veterinary Medicine, Okayama University of Science, Imabari, Japan
| | - Hitomi Igarashi
- Laboratory of Veterinary Anatomy, Department of Veterinary Medicine, Okayama University of Science, Imabari, Japan
| | - Shosaku Hattori
- Amami Laboratory, The Institute of Medical Science, The University of Tokyo, Kagoshima, Japan
| | - Yoshihiro Hayashi
- Department of Veterinary Anatomy, The University of Tokyo, Tokyo, Japan.,National Museum of Nature and Science, Tokyo, Japan
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10
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Wang L, Yan M, Wu S, Mao B, Wong CKC, Ge R, Sun F, Cheng CY. Microtubule Cytoskeleton and Spermatogenesis-Lesson From Studies of Toxicant Models. Toxicol Sci 2020; 177:305-315. [PMID: 32647867 PMCID: PMC7548287 DOI: 10.1093/toxsci/kfaa109] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Studies have shown that mammalian testes, in particular the Sertoli cells, are highly susceptible to exposure of environmental toxicants, such as cadmium, perfluorooctanesulfonate, phthalates, 2,5-hexanedione and bisphenol A. However, important studies conducted by reproductive toxicologists and/or biologists in the past have been treated as toxicology reports per se. Yet, many of these studies provided important mechanistic insights on the toxicant-induced testis injury and reproductive dysfunction, relevant to the biology of the testis and spermatogenesis. Furthermore, recent studies have shown that findings obtained from toxicant models are exceedingly helpful tools to unravel the biology of testis function in particular spermatogenesis, including specific cellular events associated with spermatid transport to support spermiogenesis and spermiation. In this review, we critically evaluate some recent data, focusing primarily on the molecular structure and role of microtubules in cellular function, illustrating the importance of toxicant models to unravel the biology of microtubule cytoskeleton in supporting spermatogenesis, well beyond information on toxicology. These findings have opened up some potential areas of research which should be carefully evaluated in the years to come.
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Affiliation(s)
- Lingling Wang
- The Second Affiliated Hospital and Yuying Children’s Hospital, Wenzhou Medical University, Wenzhou, Zhejiang 325027, China
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, New York 10065
- Jiangsu Key Laboratory of Drug Screening, China Pharmaceutical University, Nanjing, Jiangsu 210009, China
| | - Ming Yan
- Jiangsu Key Laboratory of Drug Screening, China Pharmaceutical University, Nanjing, Jiangsu 210009, China
| | - Siwen Wu
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, New York 10065
- Jiangsu Key Laboratory of Drug Screening, China Pharmaceutical University, Nanjing, Jiangsu 210009, China
| | - Baiping Mao
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, New York 10065
- Jiangsu Key Laboratory of Drug Screening, China Pharmaceutical University, Nanjing, Jiangsu 210009, China
| | - Chris K C Wong
- Department of Biology, Croucher Institute for Environmental Sciences, Hong Kong Baptist University, Kowloon, Hong Kong, China
| | - Renshan Ge
- The Second Affiliated Hospital and Yuying Children’s Hospital, Wenzhou Medical University, Wenzhou, Zhejiang 325027, China
| | - Fei Sun
- Institute of Reproductive Medicine, Nantong University School of Medicine, Nantong, Jiangsu 226001, China
| | - C Yan Cheng
- The Second Affiliated Hospital and Yuying Children’s Hospital, Wenzhou Medical University, Wenzhou, Zhejiang 325027, China
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, New York 10065
- Institute of Reproductive Medicine, Nantong University School of Medicine, Nantong, Jiangsu 226001, China
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11
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Wang L, Yan M, Wu S, Wu X, Bu T, Wong CK, Ge R, Sun F, Cheng CY. Actin binding proteins, actin cytoskeleton and spermatogenesis – Lesson from toxicant models. Reprod Toxicol 2020; 96:76-89. [DOI: 10.1016/j.reprotox.2020.05.017] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2020] [Revised: 05/15/2020] [Accepted: 05/30/2020] [Indexed: 12/16/2022]
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12
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Soda T, Miyagawa Y, Fukuhara S, Tanaka H. Physiological role of actin regulation in male fertility: Insight into actin capping proteins in spermatogenic cells. Reprod Med Biol 2020; 19:120-127. [PMID: 32273816 PMCID: PMC7138945 DOI: 10.1002/rmb2.12316] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Revised: 12/14/2019] [Accepted: 12/23/2019] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND During spermatogenesis, cytoskeletal elements are essential for spermatogenic cells to change morphologically and translocate in the seminiferous tubule. Actin filaments have been revealed to be concentrated in specific regions of spermatogenic cells and are regulated by a large number of actin-binding proteins. Actin capping protein is one of the essential actin regulatory proteins, and a recent study showed that testis-specific actin capping protein may affect male infertility. METHODS The roles of actin during spermatogenesis and testis-specific actin capping protein were reviewed by referring to the previous literature. MAIN FINDINGS RESULTS Actin filaments are involved in several crucial phases of spermatogenesis including acrosome biogenesis, flagellum formation, and nuclear processes such as the formation of synaptonemal complex. Besides, an implication for capacitation and acrosome reaction was also suggested. Testis-specific actin capping proteins are suggested to be associated with the removal of excess cytoplasm in mice. By the use of high-throughput sperm proteomics, lower protein expression of testis-specific actin capping protein in infertile men was also reported. CONCLUSION Actin is involved in the crucial phases of spermatogenesis, and the altered expression of testis-specific actin capping proteins is suggested to be a cause of male infertility in humans.
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Affiliation(s)
- Tetsuji Soda
- Department of UrologyOsaka University Graduate School of MedicineSuitaJapan
- Department of UrologyOsaka Police HospitalOsakaJapan
| | - Yasushi Miyagawa
- Department of UrologyOsaka University Graduate School of MedicineSuitaJapan
- Department of UrologySumitomo HospitalOsakaJapan
| | | | - Hiromitsu Tanaka
- Faculty of Pharmaceutical SciencesNagasaki International UniversitySaseboJapan
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13
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Yang T, Yang WX. The dynamics and regulation of microfilament during spermatogenesis. Gene 2020; 744:144635. [PMID: 32244053 DOI: 10.1016/j.gene.2020.144635] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Revised: 02/28/2020] [Accepted: 03/30/2020] [Indexed: 12/22/2022]
Abstract
Spermatogenesis is a highly complex physiological process which contains spermatogonia proliferation, spermatocyte meiosis and spermatid morphogenesis. In the past decade, actin binding proteins and signaling pathways which are critical for regulating the actin cytoskeleton in testis had been found. In this review, we summarized 5 actin-binding proteins that have been proven to play important roles in the seminiferous epithelium. Lack of them perturbs spermatids polarity and the transport of spermatids. The loss of Arp2/3 complex, Formin1, Eps8, Palladin and Plastin3 cause sperm release failure suggesting their irreplaceable role in spermatogenesis. Actin regulation relies on multiple signal pathways. The PI3K/Akt signaling pathway positively regulate the mTOR pathway to promote actin reorganization in seminiferous epithelium. Conversely, TSC1/TSC2 complex, the upstream of mTOR, is activated by the LKB1/AMPK pathway to inhibit cell proliferation, differentiation and migration. The increasing researches focus on the function of actin binding proteins (ABPs), however, their collaborative regulation of actin patterns and potential regulatory signaling networks remains unclear. We reviewed ABPs that play important roles in mammalian spermatogenesis and signal pathways involved in the regulation of microfilaments. We suggest that more relevant studies should be performed in the future.
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Affiliation(s)
- Tong Yang
- The Sperm Laboratory, College of Life Sciences, Zhejiang University, Hangzhou 310058, China
| | - Wan-Xi Yang
- The Sperm Laboratory, College of Life Sciences, Zhejiang University, Hangzhou 310058, China.
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14
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Su W, Cheng CY. Cdc42 is involved in NC1 peptide-regulated BTB dynamics through actin and microtubule cytoskeletal reorganization. FASEB J 2019; 33:14461-14478. [PMID: 31682474 PMCID: PMC6894087 DOI: 10.1096/fj.201900991r] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Accepted: 09/23/2019] [Indexed: 12/13/2022]
Abstract
Noncollagenous domain 1 (NC1)-peptide is a biologically active peptide derived from the C-terminal region of collagen α3(IV) chain, a structural constituent protein at the basement membrane in the rat testis, likely via proteolytic cleavage of matrix metalloproteinase 9. Studies have shown that this NC1 peptide regulates testis function by inducing Sertoli cell blood-testis barrier (BTB) remodeling and is also capable of inducing elongate spermatid exfoliation through its disruptive effects on the organization of actin- and microtubule (MT)-based cytoskeletons at these cell adhesion sites. However, the underlying molecular mechanism remains unknown. NC1 peptide was found to exert its biologic effects through an activation of small GTPase cell division control protein 42 homolog (Cdc42) because cooverexpression of the dominant negative mutant of Cdc42 [namely, Cdc42-T17N (via a single mutation of amino acid residue 17 from the N terminus from Thr to Asn by site-directed mutagenesis, making it constitutively inactive)] and NC1 peptide was able to block the NC1 peptide-induced Sertoli cell tight junction-permeability barrier disruption. Their cooverexpression also blocked the NC1 peptide-induced misdistribution of BTB-associated proteins at the cell-cell interface and also disruptive cytoskeletal organization of F-actin and MTs through changes in spatial expression of the corresponding actin and MT regulatory proteins. Interestingly, NC1 peptide was also found to induce an up-regulation of phosphorylated (p)-ribosomal protein S6 (rpS6) (namely, p-rpS6-S235/S236) and a concomitant down-regulation of p-Akt1/2 (namely, p-Akt1-S473 and p-Akt2-S474), but these changes could not be blocked by overexpression of Cdc42-T17N. More importantly, NC1 peptide-induced Cdc42 activation was effectively blocked by treatment of Sertoli cell epithelium with a p-Akt1/2 activator SC79, which is also capable of blocking NC1 peptide-induced down-regulation of p-Akt1-S473 and p-Akt2/S474, but not p-rpS6-S235/S236 up-regulation. In summary, these findings illustrate that Cdc42 is working downstream of the mammalian target of rapamycin complex 1/rpS6/Akt1/2 signaling pathway to support NC1 peptide-mediated effects on Sertoli cell function in the testis using the rat as an animal model.-Su, W., Cheng, C. Y. Cdc42 is involved in NC1 peptide-regulated BTB dynamics through actin and microtubule cytoskeletal reorganization.
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Affiliation(s)
- Wenhui Su
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, Rockefeller University, New York, New York, USA
| | - C. Yan Cheng
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, Rockefeller University, New York, New York, USA
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15
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Kurohmaru M, Matsui T, Igarashi H, Hattori S, Hayashi Y. Distribution of actin filaments in the seminiferous epithelium of the Habu, Trimeresurus flavoviridis. Anat Histol Embryol 2019; 48:505-507. [PMID: 31389074 DOI: 10.1111/ahe.12475] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2019] [Accepted: 07/13/2019] [Indexed: 11/28/2022]
Abstract
The distribution of actin filaments was examined in the seminiferous epithelium of the Habu (Trimeresurus flavoviridis; snake), by transmission electron microscopy and fluorescence histochemistry. By transmission electron microscopy, actin filaments were clearly found only at the site between Sertoli cell and spermatid without a lattice-like structure. Fluorescence histochemistry showed a weak labelling of actin filaments in the seminiferous epithelium, whereas these findings seem to be common among reptiles, they are different from those in mammals. Additionally, the bundles of actin filaments adjacent to the plasma membrane of Sertoli cells, appeared in other reptiles, were not observed in the Habu.
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Affiliation(s)
- Masamichi Kurohmaru
- Laboratory of Veterinary Anatomy, Department of Veterinary Medicine, Okayama University of Science, Imabari, Japan.,Department of Veterinary Anatomy, The University of Tokyo, Tokyo, Japan
| | - Toshiyasu Matsui
- Laboratory of Veterinary Anatomy, Department of Veterinary Medicine, Okayama University of Science, Imabari, Japan
| | - Hitomi Igarashi
- Laboratory of Veterinary Anatomy, Department of Veterinary Medicine, Okayama University of Science, Imabari, Japan
| | - Shosaku Hattori
- Amami Laboratory, The Institute of Medical Science, The University of Tokyo, Kagoshima, Japan
| | - Yoshihiro Hayashi
- Department of Veterinary Anatomy, The University of Tokyo, Tokyo, Japan
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16
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Regulation of Blood-Testis Barrier (BTB) Dynamics, Role of Actin-, and Microtubule-Based Cytoskeletons. Methods Mol Biol 2019; 1748:229-243. [PMID: 29453575 DOI: 10.1007/978-1-4939-7698-0_16] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The blood-testis barrier (BTB) is an important ultrastructure in the testis that supports meiosis and postmeiotic spermatid development since a delay in the establishment of a functional Sertoli cell barrier during postnatal development in rats or mice by 17-20 day postpartum (dpp) would lead to a delay of the first wave of meiosis. Furthermore, irreversible disruption of the BTB by toxicants also induces infertility in rodents. Herein, we summarize recent findings that BTB dynamics (i.e., disassembly, reassembly, and stabilization) are supported by the concerted efforts of the actin- and microtubule (MT)-based cytoskeletons. We focus on the role of two actin nucleation protein complexes, namely, the Arp2/3 (actin-related protein 2/3) complex and formin 1 (or the formin 1/spire 1 complex) known to induce actin nucleation, respectively, by conferring plasticity to actin cytoskeleton. We also focus on the MT plus (+)-end tracking protein (+TIP) EB1 (end-binding protein 1) which is known to confer MT stabilization. Furthermore, we discuss in particular how the interactions of these proteins modulate BTB dynamics during spermatogenesis. These findings also yield a novel hypothetical concept regarding the molecular mechanism that modulates BTB function.
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17
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Wen Q, Li N, Xiao X, Lui WY, Chu DS, Wong CKC, Lian Q, Ge R, Lee WM, Silvestrini B, Cheng CY. Actin nucleator Spire 1 is a regulator of ectoplasmic specialization in the testis. Cell Death Dis 2018; 9:208. [PMID: 29434191 PMCID: PMC5833730 DOI: 10.1038/s41419-017-0201-6] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2017] [Revised: 11/10/2017] [Accepted: 12/06/2017] [Indexed: 01/26/2023]
Abstract
Germ cell differentiation during the epithelial cycle of spermatogenesis is accompanied by extensive remodeling at the Sertoli cell-cell and Sertoli cell-spermatid interface to accommodate the transport of preleptotene spermatocytes and developing spermatids across the blood-testis barrier (BTB) and the adluminal compartment of the seminiferous epithelium, respectively. The unique cell junction in the testis is the actin-rich ectoplasmic specialization (ES) designated basal ES at the Sertoli cell-cell interface, and the apical ES at the Sertoli-spermatid interface. Since ES dynamics (i.e., disassembly, reassembly and stabilization) are supported by actin microfilaments, which rapidly converts between their bundled and unbundled/branched configuration to confer plasticity to the ES, it is logical to speculate that actin nucleation proteins play a crucial role to ES dynamics. Herein, we reported findings that Spire 1, an actin nucleator known to polymerize actins into long stretches of linear microfilaments in cells, is an important regulator of ES dynamics. Its knockdown by RNAi in Sertoli cells cultured in vitro was found to impede the Sertoli cell tight junction (TJ)-permeability barrier through changes in the organization of F-actin across Sertoli cell cytosol. Unexpectedly, Spire 1 knockdown also perturbed microtubule (MT) organization in Sertoli cells cultured in vitro. Biochemical studies using cultured Sertoli cells and specific F-actin vs. MT polymerization assays supported the notion that a transient loss of Spire 1 by RNAi disrupted Sertoli cell actin and MT polymerization and bundling activities. These findings in vitro were reproduced in studies in vivo by RNAi using Spire 1-specific siRNA duplexes to transfect testes with Polyplus in vivo-jetPEI as a transfection medium with high transfection efficiency. Spire 1 knockdown in the testis led to gross disruption of F-actin and MT organization across the seminiferous epithelium, thereby impeding the transport of spermatids and phagosomes across the epithelium and perturbing spermatogenesis. In summary, Spire 1 is an ES regulator to support germ cell development during spermatogenesis.
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Affiliation(s)
- Qing Wen
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, 1230 York Avenue, New York, NY, 10065, USA
| | - Nan Li
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, 1230 York Avenue, New York, NY, 10065, USA
| | - Xiang Xiao
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, 1230 York Avenue, New York, NY, 10065, USA
- Department of Reproductive Physiology, Zhejiang Academy of Medical Sciences, Hangzhou, China
| | - Wing-Yee Lui
- School of Biological Sciences, University of Hong Kong, Hong Kong, China
| | - Darren S Chu
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, 1230 York Avenue, New York, NY, 10065, USA
| | - Chris K C Wong
- Department of Biology, Hong Kong Baptist University, Hong Kong, China
| | - Qingquan Lian
- The Second Affiliated Hospital & Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Renshan Ge
- The Second Affiliated Hospital & Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Will M Lee
- School of Biological Sciences, University of Hong Kong, Hong Kong, China
| | | | - C Yan Cheng
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, 1230 York Avenue, New York, NY, 10065, USA.
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18
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Li L, Tang EI, Chen H, Lian Q, Ge R, Silvestrini B, Cheng CY. Sperm Release at Spermiation Is Regulated by Changes in the Organization of Actin- and Microtubule-Based Cytoskeletons at the Apical Ectoplasmic Specialization-A Study Using the Adjudin Model. Endocrinology 2017; 158:4300-4316. [PMID: 29040437 PMCID: PMC5711386 DOI: 10.1210/en.2017-00660] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/21/2017] [Accepted: 10/05/2017] [Indexed: 12/20/2022]
Abstract
The mechanism that regulates sperm release at spermiation is unknown. Herein, we used an animal model wherein rats were treated with adjudin, 1-(2,4-dichlorobenzyl)-1H-indazole-3-carbohydrazide, via oral gavage to induce premature release of elongating/elongated spermatids, followed by round spermatids and spermatocytes. Spermatid release mimicking spermiation occurred within 6 to 12 hours following adjudin treatment and, by 96 hours, virtually all tubules were devoid of elongating/elongated spermatids. Using this model, we tracked the organization of F-actin and microtubules (MTs) by immunofluorescence microscopy, and the association of actin or MT regulatory proteins that either promote or demolish cytoskeletal integrity through changes in the organization of actin microfilaments or MTs by coimmunoprecipitation. Adjudin treatment induced an increase in the association of (1) epidermal growth factor receptor pathway substrate 8 (an actin barbed-end capping and bundling protein) or formin 1 (an actin nucleator) with actin and (2) end-binding protein 1 (an MT stabilizing protein) with MT shortly after adjudin exposure (at 6 hours), in an attempt to maintain spermatid adhesion to the Sertoli cell at the apical ectoplasmic specialization (ES). However, this was followed by a considerable decline of their steady-state protein levels, replacing with an increase in association of (1) actin-related protein 3 (a branched actin nucleator that converts actin filaments into a branched/unbundled network) with actin and (2) MT affinity-regulating kinase 4 (an MT destabilizing protein kinase) with MTs by 12 hours after adjudin treatment. These latter changes thus promoted actin and MT disorganization, leading to apical ES disruption and the release of elongating/elongated spermatids, mimicking spermiation. In summary, spermiation is a cytoskeletal-dependent event, involving regulatory proteins that modify cytoskeletal organization.
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Affiliation(s)
- Linxi Li
- Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, New York, New York 10065
- 2Second Affiliated Hospital and Yuying Children’s Hospital, Wenzhou Medical University, Wenzhou, Zhejiang 325027, China
| | - Elizabeth I. Tang
- Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, New York, New York 10065
| | - Haiqi Chen
- Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, New York, New York 10065
| | - Qingquan Lian
- 2Second Affiliated Hospital and Yuying Children’s Hospital, Wenzhou Medical University, Wenzhou, Zhejiang 325027, China
| | - Renshan Ge
- 2Second Affiliated Hospital and Yuying Children’s Hospital, Wenzhou Medical University, Wenzhou, Zhejiang 325027, China
| | | | - C. Yan Cheng
- Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, New York, New York 10065
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19
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Wu D, Huang CJ, Jiao XF, Ding ZM, Zhang JY, Chen F, Wang YS, Li X, Huo LJ. Olaquindox disrupts tight junction integrity and cytoskeleton architecture in mouse Sertoli cells. Oncotarget 2017; 8:88630-88644. [PMID: 29179463 PMCID: PMC5687633 DOI: 10.18632/oncotarget.20289] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2017] [Accepted: 07/26/2017] [Indexed: 02/06/2023] Open
Abstract
Sertoli cells, by creating an immune-privileged and nutrition supporting environment, maintain mammalian spermatogenesis and thereby holds the heart of male fertility. Olaquindox, an effective feed additive in livestock industry, could potentially expose human into the risk of biological hazards due to its genotoxicity and cytotoxicity, highlighting the significance of determining its bio-safety regarding human reproduction. Herein, we deciphered the detrimental effects of olaquindox on male fertility by mechanistically unraveling how olaquindox intervenes blood-testis barrier in mouse. Olaquindox (400 μg/ml) exposure significantly compromised tight junction permeability function, decreased or dislocated the junction proteins (e.g., ZO-1, occludin and N-cadherin) and attenuated mTORC2 signaling pathway in primary Sertoli cells. Furthermore, olaquindox disrupted F-actin architecture through interfering with the expression of actin branching protein complex (CDC42-N-WASP-Arp3) and actin bunding protein palladin. Olaquindox also triggered severely DNA damage and apoptosis while inhibiting autophagic flux in Sertoli cell presumably due to the exacerbated generation of reactive oxygen species (ROS). Pre-treatment with antioxidant N-acetylcysteine effectively ameliorated olaquindox-induced exhaustion of ZO-1 and N-Cadherin proteins, DNA damage and apoptosis. More significantly, olaquindox disrupted the epigenetic status in Sertoli cells with hypermethylation and concomitantly hypoacetylation of H3K9 and H3K27. Overall, our study determines olaquindox targets Sertoli cells to affect BTB function through tight junction proteins and F-actin orgnization, which might disrupt the process of spermatogenesis.
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Affiliation(s)
- Di Wu
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan 430070, Hubei, China.,Department of Hubei Province Engineering Research Center in Buffalo Breeding and Products, Wuhan 430070, Hubei, China
| | - Chun-Jie Huang
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan 430070, Hubei, China.,Department of Hubei Province Engineering Research Center in Buffalo Breeding and Products, Wuhan 430070, Hubei, China
| | - Xiao-Fei Jiao
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan 430070, Hubei, China.,Department of Hubei Province Engineering Research Center in Buffalo Breeding and Products, Wuhan 430070, Hubei, China
| | - Zhi-Ming Ding
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan 430070, Hubei, China.,Department of Hubei Province Engineering Research Center in Buffalo Breeding and Products, Wuhan 430070, Hubei, China
| | - Jia-Yu Zhang
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan 430070, Hubei, China.,Department of Hubei Province Engineering Research Center in Buffalo Breeding and Products, Wuhan 430070, Hubei, China
| | - Fan Chen
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan 430070, Hubei, China.,Department of Hubei Province Engineering Research Center in Buffalo Breeding and Products, Wuhan 430070, Hubei, China
| | - Yong-Sheng Wang
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan 430070, Hubei, China.,Department of Hubei Province Engineering Research Center in Buffalo Breeding and Products, Wuhan 430070, Hubei, China
| | - Xiang Li
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan 430070, Hubei, China.,Department of Hubei Province Engineering Research Center in Buffalo Breeding and Products, Wuhan 430070, Hubei, China
| | - Li-Jun Huo
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan 430070, Hubei, China.,Department of Hubei Province Engineering Research Center in Buffalo Breeding and Products, Wuhan 430070, Hubei, China
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20
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Sun HM, Chen XL, Chen XJ, Liu J, Ma L, Wu HY, Huang QH, Xi XD, Yin T, Zhu J, Chen Z, Chen SJ. PALLD Regulates Phagocytosis by Enabling Timely Actin Polymerization and Depolymerization. THE JOURNAL OF IMMUNOLOGY 2017; 199:1817-1826. [PMID: 28739877 DOI: 10.4049/jimmunol.1602018] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Accepted: 06/12/2017] [Indexed: 12/28/2022]
Abstract
PALLD is an actin cross-linker supporting cellular mechanical tension. However, its involvement in the regulation of phagocytosis, a cellular activity essential for innate immunity and physiological tissue turnover, is unclear. We report that PALLD is highly induced along with all-trans-retinoic acid-induced maturation of myeloid leukemia cells, to promote Ig- or complement-opsonized phagocytosis. PALLD mechanistically facilitates phagocytic receptor clustering by regulating actin polymerization and c-Src dynamic activation during particle binding and early phagosome formation. PALLD is also required at the nascent phagosome to recruit phosphatase oculocerebrorenal syndrome of Lowe, which regulates phosphatidylinositol-4,5-bisphosphate hydrolysis and actin depolymerization to complete phagosome closure. Collectively, our results show a new function for PALLD as a crucial regulator of the early phase of phagocytosis by elaborating dynamic actin polymerization and depolymerization.
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Affiliation(s)
- Hai-Min Sun
- State Key Laboratory of Medical Genomics, Shanghai Institute of Hematology, RuiJin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Xin-Lei Chen
- State Key Laboratory of Medical Genomics, Shanghai Institute of Hematology, RuiJin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Xin-Jie Chen
- State Key Laboratory of Medical Genomics, Shanghai Institute of Hematology, RuiJin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Jin Liu
- State Key Laboratory of Medical Genomics, Shanghai Institute of Hematology, RuiJin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Lie Ma
- State Key Laboratory of Medical Genomics, Shanghai Institute of Hematology, RuiJin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Hai-Yan Wu
- State Key Laboratory of Medical Genomics, Shanghai Institute of Hematology, RuiJin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Qiu-Hua Huang
- State Key Laboratory of Medical Genomics, Shanghai Institute of Hematology, RuiJin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Xiao-Dong Xi
- State Key Laboratory of Medical Genomics, Shanghai Institute of Hematology, RuiJin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Tong Yin
- State Key Laboratory of Medical Genomics, Shanghai Institute of Hematology, RuiJin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Jiang Zhu
- State Key Laboratory of Medical Genomics, Shanghai Institute of Hematology, RuiJin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Zhu Chen
- State Key Laboratory of Medical Genomics, Shanghai Institute of Hematology, RuiJin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Sai-Juan Chen
- State Key Laboratory of Medical Genomics, Shanghai Institute of Hematology, RuiJin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
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Abstract
Myosin VI (MVI) is a versatile actin-based motor protein that has been implicated in a variety of different cellular processes, including endo- and exocytic vesicle trafficking, Golgi morphology, and actin structure stabilization. A role for MVI in crucial actin-based processes involved in sperm maturation was demonstrated in Drosophila. Because of the prominence and importance of actin structures in mammalian spermiogenesis, we investigated whether MVI was associated with actin-mediated maturation events in mammals. Both immunofluorescence and ultrastructural analyses using immunogold labeling showed that MVI was strongly linked with key structures involved in sperm development and maturation. During the early stage of spermiogenesis, MVI is associated with the Golgi and with coated and uncoated vesicles, which fuse to form the acrosome. Later, as the acrosome spreads to form a cap covering the sperm nucleus, MVI is localized to the acroplaxome, an actin-rich structure that anchors the acrosome to the nucleus. Finally, during the elongation/maturation phase, MVI is associated with the actin-rich structures involved in nuclear shaping: the acroplaxome, manchette, and Sertoli cell actin hoops. Since this is the first report of MVI expression and localization during mouse spermiogenesis and MVI partners in developing sperm have not yet been identified, we discuss some probable roles for MVI in this process. During early stages, MVI is hypothesized to play a role in Golgi morphology and function as well as in actin dynamics regulation important for attachment of developing acrosome to the nuclear envelope. Next, the protein might also play anchoring roles to help generate forces needed for spermatid head elongation. Moreover, association of MVI with actin that accumulates in the Sertoli cell ectoplasmic specialization and other actin structures in surrounding cells suggests additional MVI functions in spermatid movement across the seminiferous epithelium and in sperm release.
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22
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Li N, Wong CK, Cheng CY. Plastins regulate ectoplasmic specialization via its actin bundling activity on microfilaments in the rat testis. Asian J Androl 2017; 18:716-22. [PMID: 26608945 PMCID: PMC5000794 DOI: 10.4103/1008-682x.166583] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Plastins are a family of actin binding proteins (ABPs) known to cross-link actin microfilaments in mammalian cells, creating actin microfilament bundles necessary to confer cell polarity and cell shape. Plastins also support cell movement in response to changes in environment, involved in cell/tissue growth and development. They also confer plasticity to cells and tissues in response to infection or other pathological conditions (e.g., inflammation). In the testis, the cell-cell anchoring junction unique to the testis that is found at the Sertoli cell-cell interface at the blood-testis barrier (BTB) and at the Sertoli-spermatid (e.g., 8–19 spermatids in the rat testis) is the basal and the apical ectoplasmic specialization (ES), respectively. The ES is an F-actin-rich anchoring junction constituted most notably by actin microfilament bundles. A recent report using RNAi that specifically knocks down plastin 3 has yielded some insightful information regarding the mechanism by which plastin 3 regulates the status of actin microfilament bundles at the ES via its intrinsic actin filament bundling activity. Herein, we provide a brief review on the role of plastins in the testis in light of this report, which together with recent findings in the field, we propose a likely model by which plastins regulate ES function during the epithelial cycle of spermatogenesis via their intrinsic activity on actin microfilament organization in the rat testis.
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Affiliation(s)
- Nan Li
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, 1230 York Avenue, New York 10065, USA
| | - Chris Kc Wong
- Department of Biology, Hong Kong Baptist University, Hong Kong, China
| | - C Yan Cheng
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, 1230 York Avenue, New York 10065, USA
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23
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Abstract
Drebrin is a family of actin-binding proteins with two known members called drebrin A and E. Apart from the ability to stabilize F-actin microfilaments via their actin-binding domains near the N-terminus, drebrin also regulates multiple cellular functions due to its unique ability to recruit multiple binding partners to a specific cellular domain, such as the seminiferous epithelium during the epithelial cycle of spermatogenesis. Recent studies have illustrated the role of drebrin E in the testis during spermatogenesis in particular via its ability to recruit branched actin polymerization protein known as actin-related protein 3 (Arp3), illustrating its involvement in modifying the organization of actin microfilaments at the ectoplasmic specialization (ES) which includes the testis-specific anchoring junction at the Sertoli-spermatid (apical ES) interface and at the Sertoli cell-cell (basal ES) interface. These data are carefully evaluated in light of other recent findings herein regarding the role of drebrin in actin filament organization at the ES. We also provide the hypothetical model regarding its involvement in germ cell transport during the epithelial cycle in the seminiferous epithelium to support spermatogenesis.
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Affiliation(s)
- Haiqi Chen
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, 1230 York Ave., New York, NY, 10065, USA
| | - Michelle W M Li
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, 1230 York Ave., New York, NY, 10065, USA
| | - C Yan Cheng
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, 1230 York Ave., New York, NY, 10065, USA.
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Annexin A2 is critical for blood-testis barrier integrity and spermatid disengagement in the mammalian testis. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2016; 1864:527-545. [PMID: 27974247 DOI: 10.1016/j.bbamcr.2016.12.012] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2016] [Revised: 12/06/2016] [Accepted: 12/09/2016] [Indexed: 01/08/2023]
Abstract
Throughout spermatogenesis, two important processes occur at late stage VIII of the seminiferous epithelial cycle in the rat testis: preleptotene spermatocytes commence entry into the adluminal compartment and step 19 spermatids release from the seminiferous epithelium. Presently, it is not clear how these processes, which involve extensive restructuring of unique Sertoli-Sertoli and Sertoli-germ cell junctions, are mediated. We aimed to determine whether annexin A2 (ANXA2), a Ca2+-dependent and phospholipid-binding protein, participates in cell junction dynamics. To address this, in vitro and in vivo RNA interference studies were performed on prepubertal Sertoli cells and adult rat testes. The endpoints of Anxa2 knockdown were determined by immunoblotting, morphological analyses, fluorescent immunostaining, and barrier integrity assays. In the testis, ANXA2 localized to the Sertoli cell stalk, with specific staining at the blood-testis barrier and the concave (ventral) surface of elongated spermatids. ANXA2 also bound actin when testis lysates were used for immunoprecipitation. Anxa2 knockdown was found to disrupt the Sertoli cell/blood-testis barrier in vitro and in vivo. The disruption in barrier function was substantiated by changes in the localization of claudin-11, zona occludens-1, N-cadherin, and β-catenin. Furthermore, Anxa2 knockdown resulted in spermiation defects caused by a dysfunction of tubulobulbar complexes, testis-specific actin-rich ultrastructures that internalize remnant cell junction components prior to spermiation. Additionally, there were changes in the localization of several tubulobulbar complex component proteins, including actin-related protein 3, cortactin, and dynamin I/II. Our results indicate that ANXA2 is critical for the integrity of the blood-testis barrier and the timely release of spermatids.
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25
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Lee M, San Martín A, Valdivia A, Martin-Garrido A, Griendling KK. Redox-Sensitive Regulation of Myocardin-Related Transcription Factor (MRTF-A) Phosphorylation via Palladin in Vascular Smooth Muscle Cell Differentiation Marker Gene Expression. PLoS One 2016; 11:e0153199. [PMID: 27088725 PMCID: PMC4835087 DOI: 10.1371/journal.pone.0153199] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2015] [Accepted: 03/24/2016] [Indexed: 01/18/2023] Open
Abstract
Vascular smooth muscle cells (VSMCs) undergo a phenotypic switch from a differentiated to synthetic phenotype in cardiovascular diseases such as atherosclerosis and restenosis. Our previous studies indicate that transforming growth factor-β (TGF-β) helps to maintain the differentiated phenotype by regulating expression of pro-differentiation genes such as smooth muscle α-actin (SMA) and Calponin (CNN) through reactive oxygen species (ROS) derived from NADPH oxidase 4 (Nox4) in VSMCs. In this study, we investigated the relationship between Nox4 and myocardin-related transcription factor-A (MRTF-A), a transcription factor known to be important in expression of smooth muscle marker genes. Previous work has shown that MRTF-A interacts with the actin-binding protein, palladin, although how this interaction affects MRTF-A function is unclear, as is the role of phosphorylation in MRTF-A activity. We found that Rho kinase (ROCK)-mediated phosphorylation of MRTF-A is a key event in the regulation of SMA and CNN in VSMCs and that this phosphorylation depends upon Nox4-mediated palladin expression. Knockdown of Nox4 using siRNA decreases TGF-β -induced palladin expression and MRTF-A phosphorylation, suggesting redox-sensitive regulation of this signaling pathway. Knockdown of palladin also decreases MRTF-A phosphorylation. These data suggest that Nox4-dependent palladin expression and ROCK regulate phosphorylation of MRTF-A, a critical factor in the regulation of SRF responsive gene expression.
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Affiliation(s)
- Minyoung Lee
- Department of Medicine, Division of Cardiology, Emory University, Atlanta, Georgia, United Sates of America
| | - Alejandra San Martín
- Department of Medicine, Division of Cardiology, Emory University, Atlanta, Georgia, United Sates of America
| | - Alejandra Valdivia
- Department of Medicine, Division of Cardiology, Emory University, Atlanta, Georgia, United Sates of America
| | - Abel Martin-Garrido
- Department of Medicine, Division of Cardiology, Emory University, Atlanta, Georgia, United Sates of America
| | - Kathy K. Griendling
- Department of Medicine, Division of Cardiology, Emory University, Atlanta, Georgia, United Sates of America
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26
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Tang EI, Lee WM, Cheng CY. Coordination of Actin- and Microtubule-Based Cytoskeletons Supports Transport of Spermatids and Residual Bodies/Phagosomes During Spermatogenesis in the Rat Testis. Endocrinology 2016; 157:1644-59. [PMID: 26894662 PMCID: PMC4816739 DOI: 10.1210/en.2015-1962] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Germ cell transport across the seminiferous epithelium during spermatogenesis requires the intricate coordination of cell junctions, signaling proteins, and both actin- and microtubule (MT)-based cytoskeletons. Although the involvement of cytoskeletons in germ cell transport has been suggested, the precise mechanism(s) remains elusive. Based on growing evidence that actin and MT interactions underlie fundamental cellular processes, such as cell motility, it is unlikely that actin- and MT-based cytoskeletons work independently to regulate germ cell transport in the testis. Using rats treated with adjudin, a potential male contraceptive that disrupts spermatid adhesion and transport in the testis, as a study model, we show herein that actin- and MT-based cytoskeletons are both necessary for transport of spermatids and residual bodies/phagosomes across the seminiferous epithelium in adult rat testes. Analysis of intratubular expression of F-actin and tubulin revealed disruption of both actin and MT networks, concomitant with misdirected spermatids and phagosomes in rats treated with adjudin. Actin regulatory proteins, epidermal growth factor receptor pathway substrate 8 and actin-related protein 3, were mislocalized and down-regulated at the actin-rich anchoring junction between germ and Sertoli cells (apical ectoplasmic specialization) after adjudin treatment. Nonreceptor tyrosine kinase p-FAK-Tyr(407), known to regulate F-actin nucleation via actin-related protein 3, was also mislocalized and down-regulated at the apical ectoplasmic specialization, corroborating the observation of actin cytoskeleton disruption. Additionally, spatiotemporal expression of MT regulatory protein end-binding protein 1, shown to be involved in MT-actin cross talk herein, was also disrupted after adjudin treatment. In summary, spermatid/phagosome transport across the epithelium during spermatogenesis requires the coordination between actin- and MT-based cytoskeletons.
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Affiliation(s)
- Elizabeth I Tang
- The Mary M. Wohlford Laboratory for Male Contraceptive Research (E.I.T., C.Y.C.), Center for Biomedical Research, Population Council, New York, New York 10065; and School of Biological Sciences (W.M.L.), The University of Hong Kong, Hong Kong, China
| | - Will M Lee
- The Mary M. Wohlford Laboratory for Male Contraceptive Research (E.I.T., C.Y.C.), Center for Biomedical Research, Population Council, New York, New York 10065; and School of Biological Sciences (W.M.L.), The University of Hong Kong, Hong Kong, China
| | - C Yan Cheng
- The Mary M. Wohlford Laboratory for Male Contraceptive Research (E.I.T., C.Y.C.), Center for Biomedical Research, Population Council, New York, New York 10065; and School of Biological Sciences (W.M.L.), The University of Hong Kong, Hong Kong, China
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27
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Gungor-Ordueri NE, Celik-Ozenci C, Cheng CY. Ezrin: a regulator of actin microfilaments in cell junctions of the rat testis. Asian J Androl 2016; 17:653-8. [PMID: 25652626 PMCID: PMC4492059 DOI: 10.4103/1008-682x.146103] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Ezrin, radixin, moesin and merlin (ERM) proteins are highly homologous actin-binding proteins that share extensive sequence similarity with each other. These proteins tether integral membrane proteins and their cytoplasmic peripheral proteins (e.g., adaptors, nonreceptor protein kinases and phosphatases) to the microfilaments of actin-based cytoskeleton. Thus, these proteins are crucial to confer integrity of the apical membrane domain and its associated junctional complex, namely the tight junction and the adherens junction. Since ectoplasmic specialization (ES) is an F-actin-rich testis-specific anchoring junction-a highly dynamic ultrastructure in the seminiferous epithelium due to continuous transport of germ cells, in particular spermatids, across the epithelium during the epithelial cycle-it is conceivable that ERM proteins are playing an active role in these events. Although these proteins were first reported almost 25 years and have since been extensively studied in multiple epithelia/endothelia, few reports are found in the literature to examine their role in the actin filament bundles at the ES. Studies have shown that ezrin is also a constituent protein of the actin-based tunneling nanotubes (TNT) also known as intercellular bridges, which are transient cytoplasmic tubular ultrastructures that transport signals, molecules and even organelles between adjacent and distant cells in an epithelium to coordinate cell events that occur across an epithelium. Herein, we critically evaluate recent data on ERM in light of recent findings in the field in particular ezrin regarding its role in actin dynamics at the ES in the testis, illustrating additional studies are warranted to examine its physiological significance in spermatogenesis.
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Affiliation(s)
| | | | - C Yan Cheng
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, USA
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28
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Li N, Mruk DD, Lee WM, Wong CKC, Cheng CY. Is toxicant-induced Sertoli cell injury in vitro a useful model to study molecular mechanisms in spermatogenesis? Semin Cell Dev Biol 2016; 59:141-156. [PMID: 26779951 DOI: 10.1016/j.semcdb.2016.01.003] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Accepted: 01/05/2016] [Indexed: 12/25/2022]
Abstract
Sertoli cells isolated from rodents or humans and cultured in vitro are known to establish a functional tight junction (TJ)-permeability barrier that mimics the blood-testis barrier (BTB) in vivo. This model has been widely used by investigators to study the biology of the TJ and the BTB. Studies have shown that environmental toxicants (e.g., perfluorooctanesulfonate (PFOS), bisphenol A (BPA) and cadmium) that exert their disruptive effects to induce Sertoli cell injury using this in vitro model are reproducible in studies in vivo. Thus, this in vitro system provides a convenient approach to probe the molecular mechanism(s) underlying toxicant-induced testis injury but also to provide new insights in understanding spermatogenesis, such as the biology of cell adhesion, BTB restructuring that supports preleptotene spermatocyte transport, and others. Herein, we provide a brief and critical review based on studies using this in vitro model of Sertoli cell cultures using primary cells isolated from rodent testes vs. humans to monitor environmental toxicant-mediated Sertoli cell injury. In short, recent findings have shown that environmental toxicants exert their effects on Sertoli cells to induce testis injury through their action on Sertoli cell actin- and/or microtubule-based cytoskeleton. These effects are mediated via their disruptive effects on actin- and/or microtubule-binding proteins. Sertoli cells also utilize differential spatiotemporal expression of these actin binding proteins to confer plasticity to the BTB to regulate germ cell transport across the BTB.
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Affiliation(s)
- Nan Li
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, 1230 York Ave, New York, NY 10065, United States
| | - Dolores D Mruk
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, 1230 York Ave, New York, NY 10065, United States
| | - Will M Lee
- School of Biological Sciences, University of Hong Kong, Hong Kong, China
| | - Chris K C Wong
- Department of Biology, Hong Kong Baptist University, Hong Kong, China
| | - C Yan Cheng
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, 1230 York Ave, New York, NY 10065, United States.
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29
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Chen H, Mruk DD, Xia W, Bonanomi M, Silvestrini B, Cheng CY. Effective Delivery of Male Contraceptives Behind the Blood-Testis Barrier (BTB) - Lesson from Adjudin. Curr Med Chem 2016; 23:701-13. [PMID: 26758796 PMCID: PMC4845722 DOI: 10.2174/0929867323666160112122724] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2014] [Revised: 12/18/2014] [Accepted: 01/11/2016] [Indexed: 12/15/2022]
Abstract
The blood-testis barrier (BTB) is one of the tightest blood-tissue barriers in the mammalian body. It divides the seminiferous epithelium of the seminiferous tubule, the functional unit of the testis, where spermatogenesis takes place, into the basal and the adluminal (apical) compartments. Functionally, the BTB provides a unique microenvironment for meiosis I/II and post-meiotic spermatid development which take place exclusively in the apical compartment, away from the host immune system, and it contributes to the immune privilege status of testis. However, the BTB also poses major obstacles in developing male contraceptives (e.g., adjudin) that exert their effects on germ cells in the apical compartment, such as by disrupting spermatid adhesion to the Sertoli cell, causing germ cell exfoliation from the testis. Besides the tight junction (TJ) between adjacent Sertoli cells at the BTB that restricts the entry of contraceptives from the microvessels in the interstitium to the adluminal compartment, drug transporters, such as P-glycoprotein and multidrug resistance-associated protein 1 (MRP1), are also present that actively pump drugs out of the testis, limiting drug bioavailability. Recent advances in drug formulations, such as drug particle micronization (<50 μm) and co-grinding of drug particles with ß-cyclodextrin have improved bioavailability of contraceptives via considerable increase in solubility. Herein, we discuss development in drug formulations using adjudin as an example. We also put emphasis on the possible use of nanotechnology to deliver adjudin to the apical compartment with multidrug magnetic mesoporous silica nanoparticles. These advances in technology will significantly enhance our ability to develop effective non-hormonal male contraceptives for men.
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Affiliation(s)
| | | | | | | | | | - Chuen-Yan Cheng
- Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, 1230 York Ave, New York 10065, USA..
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30
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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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Gamper I, Fleck D, Barlin M, Spehr M, El Sayad S, Kleine H, Maxeiner S, Schalla C, Aydin G, Hoss M, Litchfield DW, Lüscher B, Zenke M, Sechi A. GAR22β regulates cell migration, sperm motility, and axoneme structure. Mol Biol Cell 2015; 27:277-94. [PMID: 26564797 PMCID: PMC4713131 DOI: 10.1091/mbc.e15-06-0426] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2015] [Accepted: 11/06/2015] [Indexed: 01/24/2023] Open
Abstract
Spatiotemporal cytoskeleton remodeling is crucial for several biological processes. GAR22β interacts with EB1 via a novel noncanonical amino acid sequence and is pivotal for cell motility and focal adhesion turnover. GAR22β is also crucial for generation, motility, and ultrastructural organization of spermatozoa. Spatiotemporal cytoskeleton remodeling is pivotal for cell adhesion and migration. Here we investigated the function of Gas2-related protein on chromosome 22 (GAR22β), a poorly characterized protein that interacts with actin and microtubules. Primary and immortalized GAR22β−/− Sertoli cells moved faster than wild-type cells. In addition, GAR22β−/− cells showed a more prominent focal adhesion turnover. GAR22β overexpression or its reexpression in GAR22β−/− cells reduced cell motility and focal adhesion turnover. GAR22β–actin interaction was stronger than GAR22β–microtubule interaction, resulting in GAR22β localization and dynamics that mirrored those of the actin cytoskeleton. Mechanistically, GAR22β interacted with the regulator of microtubule dynamics end-binding protein 1 (EB1) via a novel noncanonical amino acid sequence, and this GAR22β–EB1 interaction was required for the ability of GAR22β to modulate cell motility. We found that GAR22β is highly expressed in mouse testes, and its absence resulted in reduced spermatozoa generation, lower actin levels in testes, and impaired motility and ultrastructural disorganization of spermatozoa. Collectively our findings identify GAR22β as a novel regulator of cell adhesion and migration and provide a foundation for understanding the molecular basis of diverse cytoskeleton-dependent processes.
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Affiliation(s)
- Ivonne Gamper
- Institute for Biomedical Engineering, Department of Cell Biology, RWTH Aachen University Medical School, D-52074 Aachen, Germany Helmholtz Institute for Biomedical Engineering, RWTH Aachen University, D-52074 Aachen, Germany
| | - David Fleck
- Institute for Biology II, Department of Chemosensation, RWTH Aachen University, D-52074 Aachen, Germany
| | - Meltem Barlin
- Institute for Biomedical Engineering, Department of Cell Biology, RWTH Aachen University Medical School, D-52074 Aachen, Germany Helmholtz Institute for Biomedical Engineering, RWTH Aachen University, D-52074 Aachen, Germany
| | - Marc Spehr
- Institute for Biology II, Department of Chemosensation, RWTH Aachen University, D-52074 Aachen, Germany
| | - Sara El Sayad
- Institute for Biomedical Engineering, Department of Cell Biology, RWTH Aachen University Medical School, D-52074 Aachen, Germany Helmholtz Institute for Biomedical Engineering, RWTH Aachen University, D-52074 Aachen, Germany
| | - Henning Kleine
- Institute of Biochemistry and Molecular Biology, Uniklinik RWTH Aachen, D-52074 Aachen, Germany
| | - Sebastian Maxeiner
- Institute for Biomedical Engineering, Department of Cell Biology, RWTH Aachen University Medical School, D-52074 Aachen, Germany Helmholtz Institute for Biomedical Engineering, RWTH Aachen University, D-52074 Aachen, Germany
| | - Carmen Schalla
- Institute for Biomedical Engineering, Department of Cell Biology, RWTH Aachen University Medical School, D-52074 Aachen, Germany Helmholtz Institute for Biomedical Engineering, RWTH Aachen University, D-52074 Aachen, Germany
| | - Gülcan Aydin
- Institute for Biomedical Engineering, Department of Cell Biology, RWTH Aachen University Medical School, D-52074 Aachen, Germany Helmholtz Institute for Biomedical Engineering, RWTH Aachen University, D-52074 Aachen, Germany
| | - Mareike Hoss
- Electron Microscopy Facility, Uniklinik RWTH Aachen, D-52074 Aachen, Germany
| | - David W Litchfield
- Department of Biochemistry, Schulich School of Medicine and Dentistry, University of Western Ontario, London, ON N6A 5C1, Canada
| | - Bernhard Lüscher
- Institute of Biochemistry and Molecular Biology, Uniklinik RWTH Aachen, D-52074 Aachen, Germany
| | - Martin Zenke
- Institute for Biomedical Engineering, Department of Cell Biology, RWTH Aachen University Medical School, D-52074 Aachen, Germany Helmholtz Institute for Biomedical Engineering, RWTH Aachen University, D-52074 Aachen, Germany
| | - Antonio Sechi
- Institute for Biomedical Engineering, Department of Cell Biology, RWTH Aachen University Medical School, D-52074 Aachen, Germany Helmholtz Institute for Biomedical Engineering, RWTH Aachen University, D-52074 Aachen, Germany
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Li N, Mruk DD, Wong CKC, Han D, Lee WM, Cheng CY. Formin 1 Regulates Ectoplasmic Specialization in the Rat Testis Through Its Actin Nucleation and Bundling Activity. Endocrinology 2015; 156:2969-83. [PMID: 25901598 PMCID: PMC4511136 DOI: 10.1210/en.2015-1161] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
During spermatogenesis, developing spermatids and preleptotene spermatocytes are transported across the adluminal compartment and the blood-testis barrier (BTB), respectively, so that spermatids line up near the luminal edge to prepare for spermiation, whereas preleptotene spermatocytes enter the adluminal compartment to differentiate into late spermatocytes to prepare for meiosis I/II. These cellular events involve actin microfilament reorganization at the testis-specific, actin-rich Sertoli-spermatid and Sertoli-Sertoli cell junction called apical and basal ectoplasmic specialization (ES). Formin 1, an actin nucleation protein known to promote actin microfilament elongation and bundling, was expressed at the apical ES but limited to stage VII of the epithelial cycle, whereas its expression at the basal ES/BTB stretched from stage III to stage VI, diminished in stage VII, and was undetectable in stage VIII tubules. Using an in vitro model of studying Sertoli cell BTB function by RNA interference and biochemical assays to monitor actin bundling and polymerization activity, a knockdown of formin 1 in Sertoli cells by approximately 70% impeded the tight junction-permeability function. This disruptive effect on the tight junction barrier was mediated by a loss of actin microfilament bundling and actin polymerization capability mediated by changes in the localization of branched actin-inducing protein Arp3 (actin-related protein 3), and actin bundling proteins Eps8 (epidermal growth factor receptor pathway substrate 8) and palladin, thereby disrupting cell adhesion. Formin 1 knockdown in vivo was found to impede spermatid adhesion, transport, and polarity, causing defects in spermiation in which elongated spermatids remained embedded into the epithelium in stage IX tubules, mediated by changes in the spatiotemporal expression of Arp3, Eps8, and palladin. In summary, formin 1 is a regulator of ES dynamics.
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Affiliation(s)
- Nan Li
- Center for Biomedical Research (N.L., D.D.M., C.Y.C.), Population Council, New York, New York 10065; Department of Biology (C.K.C.W.), Hong Kong Baptist University, Hong Kong, China; Department of Cell Biology (D.H.), Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing 100005, China; and School of Biological Sciences (W.M.L.), University of Hong Kong, Hong Kong, China
| | - Dolores D Mruk
- Center for Biomedical Research (N.L., D.D.M., C.Y.C.), Population Council, New York, New York 10065; Department of Biology (C.K.C.W.), Hong Kong Baptist University, Hong Kong, China; Department of Cell Biology (D.H.), Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing 100005, China; and School of Biological Sciences (W.M.L.), University of Hong Kong, Hong Kong, China
| | - Chris K C Wong
- Center for Biomedical Research (N.L., D.D.M., C.Y.C.), Population Council, New York, New York 10065; Department of Biology (C.K.C.W.), Hong Kong Baptist University, Hong Kong, China; Department of Cell Biology (D.H.), Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing 100005, China; and School of Biological Sciences (W.M.L.), University of Hong Kong, Hong Kong, China
| | - Daishu Han
- Center for Biomedical Research (N.L., D.D.M., C.Y.C.), Population Council, New York, New York 10065; Department of Biology (C.K.C.W.), Hong Kong Baptist University, Hong Kong, China; Department of Cell Biology (D.H.), Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing 100005, China; and School of Biological Sciences (W.M.L.), University of Hong Kong, Hong Kong, China
| | - Will M Lee
- Center for Biomedical Research (N.L., D.D.M., C.Y.C.), Population Council, New York, New York 10065; Department of Biology (C.K.C.W.), Hong Kong Baptist University, Hong Kong, China; Department of Cell Biology (D.H.), Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing 100005, China; and School of Biological Sciences (W.M.L.), University of Hong Kong, Hong Kong, China
| | - C Yan Cheng
- Center for Biomedical Research (N.L., D.D.M., C.Y.C.), Population Council, New York, New York 10065; Department of Biology (C.K.C.W.), Hong Kong Baptist University, Hong Kong, China; Department of Cell Biology (D.H.), Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing 100005, China; and School of Biological Sciences (W.M.L.), University of Hong Kong, Hong Kong, China
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Li N, Mruk DD, Wong CKC, Lee WM, Han D, Cheng CY. Actin-bundling protein plastin 3 is a regulator of ectoplasmic specialization dynamics during spermatogenesis in the rat testis. FASEB J 2015; 29:3788-805. [PMID: 26048141 DOI: 10.1096/fj.14-267997] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2015] [Accepted: 05/18/2015] [Indexed: 12/13/2022]
Abstract
Ectoplasmic specialization (ES) is an actin-rich adherens junction in the seminiferous epithelium of adult mammalian testes. ES is restricted to the Sertoli-spermatid (apical ES) interface, as well as the Sertoli cell-cell (basal ES) interface at the blood-testis barrier (BTB). ES is typified by the presence of an array of bundles of actin microfilaments near the Sertoli cell plasma membrane. These actin microfilament bundles require rapid debundling to convert them from a bundled to branched/unbundled configuration and vice versa to confer plasticity to support the transport of 1) spermatids in the adluminal compartment and 2) preleptotene spermatocytes at the BTB while maintaining cell adhesion. Plastin 3 is one of the plastin family members abundantly found in yeast, plant and animal cells that confers actin microfilaments their bundled configuration. Herein, plastin 3 was shown to be a component of the apical and basal ES in the rat testis, displaying spatiotemporal expression during the epithelial cycle. A knockdown (KD) of plastin 3 in Sertoli cells by RNA interference using an in vitro model to study BTB function showed that a transient loss of plastin 3 perturbed the Sertoli cell tight junction-permeability barrier, mediated by changes in the localization of basal ES proteins N-cadherin and β-catenin. More importantly, these changes were the result of an alteration of the actin microfilaments, converting from their bundled to branched configuration when examined microscopically, and validated by biochemical assays that quantified actin-bundling and polymerization activity. Moreover, these changes were confirmed by studies in vivo by plastin 3 KD in the testis in which mis-localization of N-cadherin and β-catenin was also detected at the BTB, concomitant with defects in the transport of spermatids and phagosomes and a disruption of cell adhesion most notably in elongated spermatids due to a loss of actin-bundling capability at the apical ES, which in turn affected localization of adhesion protein complexes at the site. In summary, plastin 3 is a regulator of actin microfilament bundles at the ES in which it dictates the configuration of the filamentous actin network by assuming either a bundled or unbundled/branched configuration via changes in its spatiotemporal expression during the epithelial cycle.
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Affiliation(s)
- Nan Li
- *The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, New York, USA; Department of Biology, Hong Kong Baptist University, Hong Kong, China; School of Biological Sciences, University of Hong Kong, Hong Kong, China; and Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China
| | - Dolores D Mruk
- *The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, New York, USA; Department of Biology, Hong Kong Baptist University, Hong Kong, China; School of Biological Sciences, University of Hong Kong, Hong Kong, China; and Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China
| | - Chris K C Wong
- *The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, New York, USA; Department of Biology, Hong Kong Baptist University, Hong Kong, China; School of Biological Sciences, University of Hong Kong, Hong Kong, China; and Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China
| | - Will M Lee
- *The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, New York, USA; Department of Biology, Hong Kong Baptist University, Hong Kong, China; School of Biological Sciences, University of Hong Kong, Hong Kong, China; and Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China
| | - Daishu Han
- *The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, New York, USA; Department of Biology, Hong Kong Baptist University, Hong Kong, China; School of Biological Sciences, University of Hong Kong, Hong Kong, China; and Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, 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; Department of Biology, Hong Kong Baptist University, Hong Kong, China; School of Biological Sciences, University of Hong Kong, Hong Kong, China; and Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, China
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Abstract
PURPOSE OF REVIEW The present review examines the role of actin binding proteins (ABPs) on blood-testis barrier (BTB), an androgen-dependent ultrastructure in the testis, in particular their involvement on BTB remodeling during spermatogenesis. RECENT FINDINGS The BTB divides the seminiferous epithelium into the basal and the adluminal compartments. The BTB is constituted by coexisting actin-based tight junction, basal ectoplasmic specialization, and gap junction, and also intermediate filament-based desmosome between Sertoli cells near the basement membrane. Junctions at the BTB undergo continuous remodeling to facilitate the transport of preleptotene spermatocytes residing in the basal compartment across the immunological barrier during spermatogenesis. Thus, meiosis I/II and postmeiotic spermatid development take place in the adluminal compartment behind the BTB. BTB remodeling also regulates exchanges of biomolecules between the two compartments. As tight junction, basal ectoplasmic specialization, and gap junction use F-actin for attachment, actin microfilaments rapidly convert between their bundled and unbundled/branched configuration to confer BTB plasticity. The events of actin reorganization are regulated by two major classes of ABPs that convert actin microfilaments between their bundled and branched/unbundled configuration. SUMMARY We provide a model on how ABPs regulate BTB remodeling, shedding new light on unexplained male infertility, such as environmental toxicant-induced reproductive dysfunction since the testis, in particular the BTB, is sensitive to environmental toxicants, such as cadmium, bisphenol A, phthalates, and PFOS (perfluorooctanesulfonic acid or perfluorooctane sulfonate).
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Affiliation(s)
- Nan Li
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, New York, USA
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Wu YY, Yang Y, Xu YD, Yu HL. Targeted disruption of the spermatid-specific gene Spata31
causes male infertility. Mol Reprod Dev 2015; 82:432-40. [PMID: 25930072 DOI: 10.1002/mrd.22491] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2014] [Accepted: 04/06/2015] [Indexed: 12/15/2022]
Affiliation(s)
- Yuan-Yi Wu
- Department of Urology; The First Affiliated Hospital of General Hospital of the Chinese People's Liberation Army; Beijing People's Republic of China
| | - Yong Yang
- Department of Urology; The First Affiliated Hospital of General Hospital of the Chinese People's Liberation Army; Beijing People's Republic of China
| | - Yong-De Xu
- Department of Urology; The First Affiliated Hospital of General Hospital of the Chinese People's Liberation Army; Beijing People's Republic of China
| | - Hua-Liang Yu
- Department of Urology; The First Affiliated Hospital of General Hospital of the Chinese People's Liberation Army; Beijing People's Republic of China
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Gao Y, Mruk DD, Cheng CY. Sertoli cells are the target of environmental toxicants in the testis - a mechanistic and therapeutic insight. Expert Opin Ther Targets 2015; 19:1073-90. [PMID: 25913180 DOI: 10.1517/14728222.2015.1039513] [Citation(s) in RCA: 74] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
INTRODUCTION Sertoli cells support germ cell development in the testis via an elaborate network of cell junctions that confers structural, communicating, and signaling support. However, Sertoli cell junctions and cytoskeletons are the target of environmental toxicants. Because germ cells rely on Sertoli cells for the provision of structural/functional/nutritional support, exposure of males to toxicants leads to germ cell exfoliation due to Sertoli cell injuries. Interestingly, the molecular mechanism(s) by which toxicants induce cytoskeletal disruption that leads to germ cell exfoliation is unclear, until recent years, which are discussed herein. This information can possibly be used to therapeutically manage toxicant-induced infertility/subfertility in human males. AREAS COVERED In this review, we provide a brief update on the use of Sertoli cell system developed for rodents and humans in vitro, which can be deployed in any research laboratory with minimal upfront setup costs. These systems can be used to collect reliable data applicable to studies in vivo. We also discuss the latest findings on the mechanisms by which toxicants induce Sertoli cell injury, in particular cytoskeletal disruption. We also identify candidate molecules that are likely targets of toxicants. EXPERT OPINION We provide two hypothetical models delineating the mechanism by which toxicants induce germ cell exfoliation and blood-testis barrier disruption. We also discuss molecules that are the targets of toxicants as therapeutic candidates.
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Affiliation(s)
- Ying Gao
- Population Council, Center for Biomedical Research , 1230 York Ave, New York, NY, 10065 , USA
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Xiao X, Mruk DD, Wong CKC, Cheng CY. Germ cell transport across the seminiferous epithelium during spermatogenesis. Physiology (Bethesda) 2015; 29:286-98. [PMID: 24985332 DOI: 10.1152/physiol.00001.2014] [Citation(s) in RCA: 79] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Transport of germ cells across the seminiferous epithelium is crucial to spermatogenesis. Its disruption causes infertility. Signaling molecules, such as focal adhesion kinase, c-Yes, c-Src, and intercellular adhesion molecules 1 and 2, are involved in these events by regulating actin-based cytoskeleton via their action on actin-regulating proteins, endocytic vesicle-mediated protein trafficking, and adhesion protein complexes. We critically evaluate these findings and provide a hypothetical framework that regulates these events.
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Affiliation(s)
- Xiang Xiao
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, New York; and
| | - Dolores D Mruk
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, New York; and
| | - Chris K C Wong
- Department of Biology, Hong Kong Baptist University, Hong Kong, China
| | - C Yan Cheng
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, New York; and
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Gungor-Ordueri NE, Cheng CY. Fascin - An actin binding and bundling protein in the testis and its role in ectoplasmic specialization dynamics. SPERMATOGENESIS 2015; 5:e1002733. [PMID: 26413410 DOI: 10.1080/21565562.2014.1002733] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2014] [Revised: 12/19/2014] [Accepted: 12/22/2014] [Indexed: 12/19/2022]
Abstract
In the mammalian testis such as in rats, a unique actin-rich cell-cell adherens junction (AJ) known as ectoplasmic specialization (ES) is found in the seminiferous epithelium. ES is conspicuously found between Sertoli cells near the basement membrane known as the basal ES, which together with tight junction (TJ), gap junction, and desmosome constitute the blood-testis barrier (BTB). The BTB, in turn, anatomically divides the seminiferous epithelium into the basal and the adluminal (apical) compartment. On the other hand, ES is also found at the Sertoli-spermatid interface known as apical ES which is the only anchoring device for developing step 8-19 spermatids during spermiogenesis. One of the most typical features of the ES is the array of actin microfilament bundles that lie perpendicular to the Sertoli cell plasma membrane and are sandwiched in-between the cisternae of endoplasmic reticulum and the Sertoli cell plasma membrane. While these actin filament bundles confer the adhesive strength of Sertoli cells at the BTB and also spermatids in the adluminal compartment, they must be rapidly re-organized from their bundled to unbundled/branched configuration and vice versa to provide plasticity to the ES so that preleptotene spermatocytes and spermatids can be transported across the immunological barrier and the adluminal compartment, respectively, during the epithelial cycle of spermatogenesis. Fascin is a family of actin microfilament cross-linking and bundling proteins that is known to confer bundling of parallel actin microfilaments in mammalian cells. A recent report has illustrated the significance of a fascin protein called fascin 1 in actin microfilaments at the ES, pertinent to its role in spermatogenesis (Gungor-Ordueri et al. Am J Physiol Endocrinol Metab 307, E738-753, 2004 (DOI:10.1152/ajpendo.00113.2014). In this Commentary, we critically evaluate these findings in light of the role of fascin in other mammalian cells, providing some insightful information for future investigations.
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Affiliation(s)
- N Ece Gungor-Ordueri
- 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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Tang EI, Mok KW, Lee WM, Cheng CY. EB1 regulates tubulin and actin cytoskeletal networks at the sertoli cell blood-testis barrier in male rats: an in vitro study. Endocrinology 2015; 156:680-93. [PMID: 25456071 PMCID: PMC4298315 DOI: 10.1210/en.2014-1720] [Citation(s) in RCA: 65] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
During spermatogenesis, developing germ cells are transported across the seminiferous epithelium. Studies propose that because microtubules (MTs) serve as the tracks for transporting cell organelles, they may also serve a similar function in the transport of developing germ cells. Polarized MTs may provide the tracks along which polarized actin microfilaments, which act as vehicles to transport cargo, such as preleptotene spermatocytes through the blood-testis barrier (BTB) and spermatids across the epithelium. Yet the molecular mechanism(s) underlying these events remain unknown. Using an established in vitro Sertoli cell system to study BTB function, we demonstrated herein that a MT regulatory protein end-binding protein 1 (EB1) regulates the MT- and also the actin-based cytoskeleton of the Sertoli cell BTB in the rat. EB1 serves as a coordinator between the two cytoskeletons by regulating MT polymerization and actin filament bundling to modulate germ cell transport at the Sertoli cell BTB. A knockdown of EB1 by RNA interference was found to perturb the tight junction (TJ)-permeability barrier, as evidenced by mislocalization of junctional proteins critical for barrier function to facilitate spermatocyte transport, which was likely achieved by two coordinated events. First, EB1 knockdown resulted in changes in MT polymerization, thereby perturbing MT organization in Sertoli cells in which polarized MT no longer stretched properly across the cell cytosol to serve as the tracks. Second, EB1 knockdown perturbed actin organization via its effects on the branched actin polymerization-inducing protein called Arp3 (actin-related protein 3), perturbing microfilament bundling capability based on a biochemical assay, thereby causing microfilament truncation and misorganization, disrupting the function of the vehicle. This reduced actin microfilament bundling capability thus perturbed TJ-protein distribution and localization at the BTB, destabilizing the TJ barrier, leading to its remodeling to facilitate spermatocyte transport. In summary, EB1 provides a functional link between tubulin- and actin-based cytoskeletons to confer spermatocyte transport at the BTB.
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Affiliation(s)
- Elizabeth I Tang
- The Mary M. Wohlford Laboratory for Male Contraceptive Research (E.I.T., K.-W.M., C.Y.C.), Center for Biomedical Research, Population Council, New York, New York 10065; and School of Biological Sciences (W.M.L.), University of Hong Kong, Hong Kong, China
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Cheng CY. Toxicants target cell junctions in the testis: Insights from the indazole-carboxylic acid model. SPERMATOGENESIS 2015; 4:e981485. [PMID: 26413399 PMCID: PMC4581065 DOI: 10.4161/21565562.2014.981485] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/22/2014] [Accepted: 10/23/2014] [Indexed: 12/31/2022]
Abstract
There are numerous types of junctions in the seminiferous epithelium which are integrated with, and critically dependent on the Sertoli cell cytoskeleton. These include the basal tight junctions between Sertoli cells that form the main component of the blood–testis barrier, the basal ectoplasmic specializations (basal ES) and basal tubulobulbar complexes (basal TBC) between Sertoli cells; as well as apical ES and apical TBC between Sertoli cells and the developing spermatids that orchestrate spermiogenesis and spermiation. These junctions, namely TJ, ES, and TBC interact with actin microfilament-based cytoskeleton, which together with the desmosomal junctions that interact with the intermediate filament-based cytoskeleton plus the highly polarized microtubule-based cytoskeleton are working in concert to move spermatocytes and spermatids between the basal and luminal aspect of the seminiferous epithelium. In short, these various junctions are structurally complexed with the actin- and microtubule-based cytoskeleton or intermediate filaments of the Sertoli cell. Studies have shown toxicants (e.g., cadmium, bisphenol A (BPA), perfluorooctanesulfonate (PFOS), phthalates, and glycerol), and some male contraceptives under development (e.g., adjudin, gamendazole), exert their effects, at least in part, by targeting cell junctions in the testis. The disruption of Sertoli–Sertoli cell and Sertoli–germ cell junctions, results in the loss of germ cells from the seminiferous epithelium. Adjudin, a potential male contraceptive under investigation in our laboratory, produces loss of spermatids from the seminiferous tubules through disruption of the Sertoli cell spermatid junctions and disruption of the Sertoli cell cytoskeleton. The molecular and structural changes associated with adjudin administration are described, to provide an example of the profile of changes caused by disturbance of Sertoli-germ cell and also Sertoli cell-cell junctions.
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Affiliation(s)
- 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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Gungor-Ordueri NE, Celik-Ozenci C, Cheng CY. Fascin 1 is an actin filament-bundling protein that regulates ectoplasmic specialization dynamics in the rat testis. Am J Physiol Endocrinol Metab 2014; 307:E738-53. [PMID: 25159326 PMCID: PMC4216949 DOI: 10.1152/ajpendo.00113.2014] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
In the testis, spermatids are polarized cells, with their heads pointing toward the basement membrane during maturation. This polarity is crucial to pack the maximal number of spermatids in the seminiferous epithelium so that millions of sperms can be produced daily. A loss of spermatid polarity is detected after rodents are exposed to toxicants (e.g., cadmium) or nonhormonal male contraceptives (e.g., adjudin), which is associated with a disruption on the expression and/or localization of polarity proteins. In the rat testis, fascin 1, an actin-bundling protein found in mammalian cells, was expressed by Sertoli and germ cells. Fascin 1 was a component of the ectoplasmic specialization (ES), a testis-specific anchoring junction known to confer spermatid adhesion and polarity. Its expression in the seminiferous epithelium was stage specific. Fascin 1 was localized to the basal ES at the Sertoli cell-cell interface of the blood-testis barrier in all stages of the epithelial cycle, except it diminished considerably at late stage VIII. Fascin 1 was highly expressed at the apical ES at stage VII-early stage VIII and restricted to the step 19 spermatids. Its knockdown by RNAi that silenced fascin 1 by ~70% in Sertoli cells cultured in vitro was found to perturb the tight junction-permeability barrier via a disruption of F-actin organization. Knockdown of fascin 1 in vivo by ~60-70% induced defects in spermatid polarity, which was mediated by a mislocalization and/or downregulation of actin-bundling proteins Eps8 and palladin, thereby impeding F-actin organization and disrupting spermatid polarity. In summary, these findings provide insightful information on spermatid polarity regulation.
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Affiliation(s)
- N Ece Gungor-Ordueri
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, New York; and
| | - Ciler Celik-Ozenci
- Department of Histology and Embryology, Faculty of Medicine, Akdeniz University, Antalya, Turkey
| | - C Yan Cheng
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, New York; and
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Qian X, Mruk DD, Cheng YH, Cheng CY. RAI14 (retinoic acid induced protein 14) is an F-actin regulator: Lesson from the testis. SPERMATOGENESIS 2014; 3:e24824. [PMID: 23885305 PMCID: PMC3710223 DOI: 10.4161/spmg.24824] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/27/2013] [Revised: 04/22/2013] [Accepted: 04/25/2013] [Indexed: 12/20/2022]
Abstract
RAI14 (retinoic acid induced protein 14) is an actin-binding protein first identified in the liver. In the testis, RAI14 is expressed by both Sertoli and germ cells in the seminiferous epithelium. Besides binding to actin in the testis, RAI14 is also a binding protein for palladin, an actin cross-linking and bundling protein. A recent report has shown that RAI14 displays stage-specific and spatiotemporal expression at the ES [ectoplasmic specialization, a testis-specific filamentous (F)-actin-rich adherens junction] in the seminiferous epithelium of adult rat testes during the epithelial cycle of spermatogenesis, illustrating its likely involvement in F-actin organization at the ES. Functional studies in which RAI14 was knocked down by RNAi in Sertoli cells in vitro and also in testicular cells in vivo have illustrated its role in conferring the integrity of actin filament bundles at the ES, perturbing the Sertoli cell tight junction (TJ)-pemeability barrier function in vitro, and also spermatid polarity and adhesion in vivo, thereby regulating spermatid transport at spermiation. Herein, we critically evaluate these earlier findings and also provide a likely hypothetic model based on the functional role of RAI14 at the ES, and how RAI14 is working with palladin and other actin regulatory proteins in the testis to regulate the transport of (1) spermatids and (2) preleptotene spermatocytes across the seminiferous epithelium and the blood-testis barrier (BTB), respectively, during spermatogenesis. This model should serve as a framework upon which functional experiments can be designed to better understand the biology of RAI14 and other actin-binding and regulatory proteins in the testis.
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Affiliation(s)
- Xiaojing Qian
- The Mary M. Wohlford Laboratory for Male Contraceptive Research; Center for Biomedical Research; Population Council; New York NY USA ; Department of Anatomy, Histology and Embryology; School of Basic Medicine; Peking Union Medical College; Beijing, China
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Qian X, Mruk DD, Cheng YH, Cheng CY. Actin cross-linking protein palladin and spermatogenesis. SPERMATOGENESIS 2014; 3:e23473. [PMID: 23687615 PMCID: PMC3644046 DOI: 10.4161/spmg.23473] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
In the seminiferous epithelium of the mammalian testis, the most distinctive ultrastructure is the extensive bundles of actin filaments that lie near the Sertoli-spermatid interface and the Sertoli-Sertoli cell interface known as the apical ectoplasmic specialization (apical ES) and the basal ES, respectively. These actin filament bundles not only confer strong adhesion at these sites, they are uniquely found in the testis. Recent studies have shown that ES also confers spermatid and Sertoli cell polarity in the seminiferous epithelium during the epithelial cycle. While these junctions were first described in the 1970s, there are few functional studies in the literature to examine the regulation of these actin filament bundles. It is conceivable that these actin filament bundles at the ES undergo extensive re-organization to accommodate changes in location of developing spermatids during spermiogenesis as spermatids are transported across the seminiferous epithelium. Additionally, these actin filaments are rapidly reorganized during BTB restructuring to accommodate the transit of preleptotene spermatocytes across the barrier at stage VIII of the epithelial cycle. Thus, actin binding and regulatory proteins are likely involved in these events to confer changes in F-actin organization at these sites. Interestingly, there are no reports in the field to study these regulatory proteins until recently. Herein, we summarize some of the latest findings in the field regarding a novel actin cross-linker and actin-bundling protein called palladin. We also discuss in this opinion article the likely role of palladin in regulating actin filament bundles at the ES during spermatogenesis, highlighting the significant of palladin and how this protein is plausibly working in concert with other actin-binding/regulatory proteins and components of polarity proteins to regulate the cyclic events of actin organization and re-organization during the epithelial cycle of spermatogenesis. We also propose a hypothetic model by which palladin regulates ES restructuring during the epithelial cycle of spermatogenesis.
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Affiliation(s)
- Xiaojing Qian
- The Mary M. Wohlford Laboratory for Male Contraceptive Research; Center for Biomedical Research; Population Council; New York, NY USA ; School of Basic Medicine; Peking Union Medical College; Beijing, China
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Niedenberger BA, Chappell VA, Otey CA, Geyer CB. Actin dynamics regulate subcellular localization of the F-actin-binding protein PALLD in mouse Sertoli cells. Reproduction 2014; 148:333-41. [PMID: 24989903 DOI: 10.1530/rep-14-0147] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Sertoli cells undergo terminal differentiation at puberty to support all phases of germ cell development, which occurs in the mouse beginning in the second week of life. By ∼18 days postpartum (dpp), nearly all Sertoli cells have ceased proliferation. This terminal differentiation is accompanied by the development of unique and regionally concentrated filamentous actin (F-actin) structures at the basal and apical aspects of the seminiferous epithelium, and this reorganization is likely to involve the action of actin-binding proteins. Palladin (PALLD) is a widely expressed F-actin-binding and bundling protein recently shown to regulate these structures, yet it is predominantly nuclear in Sertoli cells at puberty. We found that PALLD localized within nuclei of primary Sertoli cells grown in serum-free media but relocalized to the cytoplasm upon serum stimulation. We utilized this system with in vivo relevance to Sertoli cell development to investigate mechanisms regulating nuclear localization of this F-actin-binding protein. Our results indicate that PALLD can be shuttled from the nucleus to the cytoplasm, and that this relocalization occurred following depolymerization of the F-actin cytoskeleton in response to cAMP signaling. Nuclear localization was reduced in Hpg-mutant testes, suggesting the involvement of gonadotropin signaling. We found that PALLD nuclear localization was unaffected in testis tissues from LH receptor and androgen receptor-mutant mice. However, PALLD nuclear localization was reduced in the testes of FSH receptor-mutant mice, suggesting that FSH signaling during Sertoli cell maturation regulates this subcellular localization.
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MESH Headings
- Actin Cytoskeleton/metabolism
- Actins/metabolism
- Active Transport, Cell Nucleus
- Animals
- Cells, Cultured
- Cyclic AMP/metabolism
- Cytoplasm/metabolism
- Cytoskeletal Proteins/metabolism
- Follicle Stimulating Hormone/metabolism
- Gonadotropin-Releasing Hormone/genetics
- Gonadotropin-Releasing Hormone/metabolism
- Humans
- Karyopherins/metabolism
- Luteinizing Hormone/metabolism
- Male
- Mice
- Mice, Knockout
- Phosphoproteins/metabolism
- Protein Precursors/genetics
- Protein Precursors/metabolism
- Receptors, Androgen/genetics
- Receptors, Androgen/metabolism
- Receptors, Cytoplasmic and Nuclear/metabolism
- Receptors, FSH/genetics
- Receptors, FSH/metabolism
- Receptors, LH/genetics
- Receptors, LH/metabolism
- Sertoli Cells/metabolism
- rho GTP-Binding Proteins/metabolism
- Exportin 1 Protein
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Affiliation(s)
- Bryan A Niedenberger
- Department of Anatomy and Cell BiologyBrody School of Medicine, Greenville, North Carolina 27834, USAEast Carolina Diabetes and Obesity InstituteGreenville, North Carolina 27834, USADepartment of Cell Biology and PhysiologyUniversity of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Vesna A Chappell
- Department of Anatomy and Cell BiologyBrody School of Medicine, Greenville, North Carolina 27834, USAEast Carolina Diabetes and Obesity InstituteGreenville, North Carolina 27834, USADepartment of Cell Biology and PhysiologyUniversity of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Carol A Otey
- Department of Anatomy and Cell BiologyBrody School of Medicine, Greenville, North Carolina 27834, USAEast Carolina Diabetes and Obesity InstituteGreenville, North Carolina 27834, USADepartment of Cell Biology and PhysiologyUniversity of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Christopher B Geyer
- Department of Anatomy and Cell BiologyBrody School of Medicine, Greenville, North Carolina 27834, USAEast Carolina Diabetes and Obesity InstituteGreenville, North Carolina 27834, USADepartment of Cell Biology and PhysiologyUniversity of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA Department of Anatomy and Cell BiologyBrody School of Medicine, Greenville, North Carolina 27834, USAEast Carolina Diabetes and Obesity InstituteGreenville, North Carolina 27834, USADepartment of Cell Biology and PhysiologyUniversity of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
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Gungor-Ordueri NE, Tang EI, Celik-Ozenci C, Cheng CY. Ezrin is an actin binding protein that regulates sertoli cell and spermatid adhesion during spermatogenesis. Endocrinology 2014; 155:3981-95. [PMID: 25051438 PMCID: PMC4164919 DOI: 10.1210/en.2014-1163] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
During spermatogenesis, the transport of spermatids and the release of sperms at spermiation and the remodeling of the blood-testis barrier (BTB) in the seminiferous epithelium of rat testes require rapid reorganization of the actin-based cytoskeleton. However, the mechanism(s) and the regulatory molecule(s) remain unexplored. Herein we report findings that unfold the functional significance of ezrin in the organization of the testis-specific adherens junction at the spermatid-Sertoli cell interface called apical ectoplasmic specialization (ES) in the adluminal compartment and the Sertoli cell-cell interface known as basal ES at the BTB. Ezrin is expressed at the basal ES/BTB in all stages, except from late VIII to IX, of the epithelial cycle. Its knockdown by RNA interference (RNAi) in vitro perturbs the Sertoli cell tight junction-permeability barrier via a disruption of the actin microfilaments in Sertoli cells, which in turn impeded basal ES protein (eg, N-cadherin) distribution, perturbing the BTB function. These findings were confirmed by a knockdown study in vivo. However, the expression of ezrin at the apical ES is restricted to stage VIII of the cycle and limited only between step 19 spermatids and Sertoli cells. A knockdown of ezrin in vivo by RNAi was found to impede spermatid transport, causing defects in spermiation in which spermatids were embedded deep inside the epithelium, and associated with a loss of spermatid polarity. Also, ezrin was associated with residual bodies and phagosomes, and its knockdown by RNAi in the testis also impeded the transport of residual bodies/phagosomes from the apical to the basal compartment. In summary, ezrin is involved in regulating actin microfilament organization at the ES in rat testes.
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Affiliation(s)
- N Ece Gungor-Ordueri
- The Mary M. Wohlford Laboratory for Male Contraceptive Research (N.E.G.-O., E.I.T., C.Y.C.), Center for Biomedical Research, Population Council, New York, New York 10065; and Department of Histology and Embryology (C.C.-O.), Faculty of Medicine, Akdeniz University, 070200 Antalya, Turkey
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Abstract
An exciting frontier in biology is understanding the functions of basic cell biological machinery in complex tissues. This approach is expected to uncover novel modes of regulation as well as reveal how core machinery is repurposed by different tissues to accomplish different physiological outputs. F-actin plays roles in cell shape, adhesion, migration and signaling – diverse functions that require a specific organization established by a myriad of regulators. Here, we discuss the role of the actin nucleating Arp2/3 complex and the unexpected roles that it plays in a stratified epithelial tissue, the epidermis. While many expected phenotypes such as defects in architecture and cell adhesion were lacking, loss of the Arp2/3 complex activity resulted in epidermal barrier and differentiation defects. This teaches us that, while informative, cell culture approaches are limiting and that studies of the Arp2/3 complex in diverse tissues are expected to yield many more surprises.
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Affiliation(s)
- Terry Lechler
- Departments of Dermatology and Cell Biology, Duke University ; Durham, NC USA
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Abstract
The transport of germ cells across the seminiferous epithelium is composed of a series of cellular events during the epithelial cycle essential to the completion of spermatogenesis. Without the timely transport of spermatids during spermiogenesis, spermatozoa that are transformed from step 19 spermatids in the rat testis fail to reach the luminal edge of the apical compartment and enter the tubule lumen at spermiation, thereby arriving the epididymis for further maturation. Step 19 spermatids and/or sperms that remain in the epithelium beyond stage VIII of the epithelial cycle will be removed by the Sertoli cell via phagocytosis to form phagosomes and be degraded by lysosomes, leading to subfertility and/or infertility. However, the biology of spermatid transport, in particular the final events that lead to spermiation remain elusive. Based on recent data in the field, we critically evaluate the biology of spermiation herein by focusing on the actin binding proteins (ABPs) that regulate the organization of actin microfilaments at the Sertoli-spermatid interface, which is crucial for spermatid transport during this event. The hypothesis we put forth herein also highlights some specific areas of research that can be pursued by investigators in the years to come.
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48
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Wan HT, Mruk DD, Tang EI, Xiao X, Cheng YH, Wong EWP, Wong CKC, Cheng CY. Role of non-receptor protein tyrosine kinases in spermatid transport during spermatogenesis. Semin Cell Dev Biol 2014; 30:65-74. [PMID: 24727349 DOI: 10.1016/j.semcdb.2014.04.013] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2014] [Accepted: 04/04/2014] [Indexed: 12/16/2022]
Abstract
Non-receptor protein tyrosine kinases are cytoplasmic kinases that activate proteins by phosphorylating tyrosine residues, which in turn affect multiple functions in eukaryotic cells. Herein, we focus on the role of non-receptor protein tyrosine kinases, most notably, FAK, c-Yes and c-Src, in the transport of spermatids across the seminiferous epithelium during spermatogenesis. Since spermatids, which are formed from spermatocytes via meiosis, are immotile haploid cells, they must be transported by Sertoli cells across the seminiferous epithelium during the epithelial cycle of spermatogenesis. Without the timely transport of spermatids across the epithelium, the release of sperms at spermiation fails to occur, leading to infertility. Thus, the molecular event pertinent to spermatid transport is crucial to spermatogenesis. We provide a critical discussion based on recent findings in this review. We also provide a hypothetical model on spermatid transport, and the role of non-receptor protein tyrosine kinases in this event. We also highlight areas of research that deserve attention by investigators in the field.
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Affiliation(s)
- H T Wan
- Center for Biomedical Research, Population Council, 1230 York Avenue, New York, NY 10065, United States
| | - Dolores D Mruk
- Center for Biomedical Research, Population Council, 1230 York Avenue, New York, NY 10065, United States
| | - Elizabeth I Tang
- Center for Biomedical Research, Population Council, 1230 York Avenue, New York, NY 10065, United States
| | - Xiang Xiao
- Center for Biomedical Research, Population Council, 1230 York Avenue, New York, NY 10065, United States
| | - Yan-Ho Cheng
- Richmond University Medical Center, Staten Island, NY 10301, United States
| | - Elissa W P Wong
- Center for Biomedical Research, Population Council, 1230 York Avenue, New York, NY 10065, United States
| | - Chris K C Wong
- Department of Biology, Hong Kong Baptist University, Kowloon, Hong Kong, China
| | - C Yan Cheng
- Center for Biomedical Research, Population Council, 1230 York Avenue, New York, NY 10065, United States.
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Cheng CY, Lie PPY, Wong EWP, Mruk DD. Focal adhesion kinase and actin regulatory/binding proteins that modulate F-actin organization at the tissue barrier: Lesson from the testis. Tissue Barriers 2014; 1:e24252. [PMID: 24665388 PMCID: PMC3875635 DOI: 10.4161/tisb.24252] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2013] [Revised: 03/07/2013] [Accepted: 03/09/2013] [Indexed: 11/28/2022] Open
Abstract
Focal adhesion kinase (FAK), as its name implied, is an important mediator of integrin-based signaling function in mammalian cells at the focal adhesion complex (FAC, also known as focal contact) at the cell-extracellular matrix interface. FAK is intimately related to cell movement, such as in macrophages, fibroblasts and also tumor cells. In the testis, however, FAK and two of its phosphorylated forms, p-FAK-Tyr407 and -Tyr397, are not found at the FAC since there is no ultrastructure analogous or similar to FAC in the mammalian testis vs. other epithelia. Instead, FAK and its two phosphorylated forms are detected along the seminiferous epithelium in the rat testis at the cell-cell interface in a testis-specific adherens junction (AJ) known as the ectoplasmic specialization (ES). ES is an F-actin-rich ultrastructure in which bundles of actin filaments are sandwiched in-between plasma membrane and cisternae of endoplasmic reticulum not found in other mammalian epithelial/endothelial cells. The ES is restricted to the interface of Sertoli cells and spermatids (step 8–19) known as the apical ES, and to the Sertoli cell-cell interface known as the basal ES. Interestingly, the basal ES is also an integrated component of the blood-testis barrier (BTB), coexisting with tight junction (TJ) and gap junction (GJ), and it is conceivable that actin filament bundles at the ES undergo extensive organization, converting from their “bundled” to “de-bundled/branching” configuration to facilitate transport of germ cells across the epithelium and at the BTB during the epithelial cycle. A recent report (Lie et al. PNAS 109:12562–12567, 2012) has demonstrated that the stage-specific and spatiotemporal expression of p-FAK-Tyr407 and -Tyr397 are crucial to the regulation of these events via their stage-specific and spatiotemporal expression during the epithelial cycle mediated by their effects on the organization of the actin filament bundles at the ES, involving actin binding/regulatory proteins. In this Commentary, we will critically evaluate these findings in light of other recent reports in the field. While these ideas are based on studies in the BTB in the rat testis, this information should be applicable and helpful to investigators studying other tissue barriers.
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Affiliation(s)
- C Yan Cheng
- The Mary M. Wohlford Laboratory for Male Contraceptive Research; Center for Biomedical Research; Population Council; New York, NY USA
| | - Pearl P Y Lie
- The Mary M. Wohlford Laboratory for Male Contraceptive Research; Center for Biomedical Research; Population Council; New York, NY USA
| | - Elissa W P Wong
- The Mary M. Wohlford Laboratory for Male Contraceptive Research; Center for Biomedical Research; Population Council; New York, NY USA
| | - Dolores D Mruk
- The Mary M. Wohlford Laboratory for Male Contraceptive Research; Center for Biomedical Research; Population Council; New York, NY USA
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Gungor-Ordueri NE, Mruk DD, Wan HT, Wong EWP, Celik-Ozenci C, Lie PPY, Cheng CY. New insights into FAK function and regulation during spermatogenesis. Histol Histopathol 2014; 29:977-89. [PMID: 24578181 DOI: 10.14670/hh-29.977] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Germ cell transport across the seminiferous epithelium during the epithelial cycle is crucial to spermatogenesis, although molecular mechanism(s) that regulate these events remain unknown. Studies have shown that spatiotemporal expression of crucial regulatory proteins during the epithelial cycle represents an efficient and physiologically important mechanism to regulate spermatogenesis without involving de novo synthesis of proteins and/or expression of genes. Herein, we critically review the role of focal adhesion kinase (FAK) in coordinating the transport of spermatids and preleptotene spermatocytes across the epithelium and the BTB, respectively, along the apical ectoplasmic specialization (ES) - blood-testis barrier - basement membrane (BM) functional axis during spermatogenesis. In the testis, p-FAK-Tyr³⁸⁷ and p-FAK-Tyr⁴⁰⁷ are spatiotemporally expressed during the epithelial cycle at the actin-rich anchoring junction known as ES, regulating cell adhesion at the Sertoli-spermatid (apical ES) and Sertoli cell-cell (basal ES) interface. Phosphorylated forms of FAK exert their effects by regulating the homeostasis of F-actin at the ES, mediated via their effects on actin polymerization so that microfilaments are efficiently re-organized, such as from their "bundled" to "de-bundled/branched" configuration and vice versa during the epithelial cycle to facilitate the transport of: (i) spermatids across the epithelium, and (ii) preleptotene spermatocytes across the BTB. In summary, p-FAK-Tyr⁴⁰⁷ and p-FAK-Tyr³⁸⁷ are important regulators of spermatogenesis which serve as molecular switches that turn "on" and "off" adhesion function at the apical ES and the basal ES/BTB, mediated via their spatiotemporal expression during the epithelial cycle. A hypothetical model depicting the role of these two molecular switches is also proposed.
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Affiliation(s)
- N Ece Gungor-Ordueri
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, USA
| | - Dolores D Mruk
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, USA
| | - Hin-ting Wan
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, USA
| | - Elissa W P Wong
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, USA
| | - Ciler Celik-Ozenci
- Department of Histology and Embryology, Faculty of Medicine, Akdeniz University, Antalya, Turkey
| | - Pearl P Y Lie
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, USA
| | - C Yan Cheng
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, USA. OR
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