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Roy S, Roy S, Halder S, Jana K, Ukil A. Leishmania exploits host cAMP/EPAC/calcineurin signaling to induce an IL-33-mediated anti-inflammatory environment for the establishment of infection. J Biol Chem 2024; 300:107366. [PMID: 38750790 PMCID: PMC11208913 DOI: 10.1016/j.jbc.2024.107366] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Revised: 05/03/2024] [Accepted: 05/05/2024] [Indexed: 06/10/2024] Open
Abstract
Host anti-inflammatory responses are critical for the progression of visceral leishmaniasis, and the pleiotropic cytokine interleukin (IL)-33 was found to be upregulated in infection. Here, we documented that IL-33 induction is a consequence of elevated cAMP-mediated exchange protein activated by cAMP (EPAC)/calcineurin-dependent signaling and essential for the sustenance of infection. Leishmania donovani-infected macrophages showed upregulation of IL-33 and its neutralization resulted in decreased parasite survival and increased inflammatory responses. Infection-induced cAMP was involved in IL-33 production and of its downstream effectors PKA and EPAC, only the latter was responsible for elevated IL-33 level. EPAC initiated Rap-dependent phospholipase C activation, which triggered the release of intracellular calcium followed by calcium/calmodulin complex formation. Screening of calmodulin-dependent enzymes affirmed involvement of the phosphatase calcineurin in cAMP/EPAC/calcium/calmodulin signaling-induced IL-33 production and parasite survival. Activated calcineurin ensured nuclear localization of the transcription factors, nuclear factor of activated T cell 1 and hypoxia-inducible factor 1 alpha required for IL-33 transcription, and we further confirmed this by chromatin immunoprecipitation assay. Administering specific inhibitors of nuclear factor of activated T cell 1 and hypoxia-inducible factor 1 alpha in BALB/c mouse model of visceral leishmaniasis decreased liver and spleen parasite burden along with reduction in IL-33 level. Splenocyte supernatants of inhibitor-treated infected mice further documented an increase in tumor necrosis factor alpha and IL-12 level with simultaneous decrease of IL-10, thereby indicating an overall disease-escalating effect of IL-33. Thus, this study demonstrates that cAMP/EPAC/calcineurin signaling is crucial for the activation of IL-33 and in effect creates anti-inflammatory responses, essential for infection.
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Affiliation(s)
- Souravi Roy
- Department of Biochemistry, University of Calcutta, Kolkata, India
| | - Shalini Roy
- Department of Biochemistry, University of Calcutta, Kolkata, India
| | - Satyajit Halder
- Division of Molecular Medicine, Bose Institute, Kolkata, India
| | - Kuladip Jana
- Division of Molecular Medicine, Bose Institute, Kolkata, India
| | - Anindita Ukil
- Department of Biochemistry, University of Calcutta, Kolkata, India.
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2
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Zhang H, Yang Y, Cao Y, Guan J. Effects of chronic stress on cancer development and the therapeutic prospects of adrenergic signaling regulation. Biomed Pharmacother 2024; 175:116609. [PMID: 38678960 DOI: 10.1016/j.biopha.2024.116609] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2024] [Revised: 04/14/2024] [Accepted: 04/17/2024] [Indexed: 05/01/2024] Open
Abstract
Long-term chronic stress is an important factor in the poor prognosis of cancer patients. Chronic stress reduces the tissue infiltration of immune cells in the tumor microenvironment (TME) by continuously activating the adrenergic signaling, inhibits antitumor immune response and tumor cell apoptosis while also inducing epithelial-mesenchymal transition (EMT) and tumor angiogenesis, promoting tumor invasion and metastasis. This review first summarizes how adrenergic signaling activates intracellular signaling by binding different adrenergic receptor (AR) heterodimers. Then, we focused on reviewing adrenergic signaling to regulate multiple functions of immune cells, including cell differentiation, migration, and cytokine secretion. In addition, the article discusses the mechanisms by which adrenergic signaling exerts pro-tumorigenic effects by acting directly on the tumor itself. It also highlights the use of adrenergic receptor modulators in cancer therapy, with particular emphasis on their potential role in immunotherapy. Finally, the article reviews the beneficial effects of stress intervention measures on cancer treatment. We think that enhancing the body's antitumor response by adjusting adrenergic signaling can enhance the efficacy of cancer treatment.
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Affiliation(s)
- Hao Zhang
- Department of Oncology, The Eighth Medical Center, Chinese PLA (People's Liberation Army) General Hospital, Beijing 100091, China; Department of Oncology, The Fifth Medical Center, Chinese PLA (People's Liberation Army) General Hospital, Beijing 100071, China.
| | - Yuwei Yang
- College of Pulmonary & Critical Care Medicine, Chinese PLA General Hospital, Beijing Key Laboratory of OTIR, Beijing, 100091, China.
| | - Yan Cao
- College of Pulmonary & Critical Care Medicine, Chinese PLA General Hospital, Beijing Key Laboratory of OTIR, Beijing, 100091, China.
| | - Jingzhi Guan
- Department of Oncology, The Fifth Medical Center, Chinese PLA (People's Liberation Army) General Hospital, Beijing 100071, China.
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3
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Breitbart H, Grinshtein E. Mechanisms That Protect Mammalian Sperm from the Spontaneous Acrosome Reaction. Int J Mol Sci 2023; 24:17005. [PMID: 38069328 PMCID: PMC10707520 DOI: 10.3390/ijms242317005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2023] [Revised: 11/28/2023] [Accepted: 11/29/2023] [Indexed: 12/18/2023] Open
Abstract
To acquire the capacity to fertilize the oocyte, mammalian spermatozoa must undergo a series of biochemical reactions in the female reproductive tract, which are collectively called capacitation. The capacitated spermatozoa subsequently interact with the oocyte zona-pellucida and undergo the acrosome reaction, which enables the penetration of the oocyte and subsequent fertilization. However, the spontaneous acrosome reaction (sAR) can occur prematurely in the sperm before reaching the oocyte cumulus oophorus, thereby jeopardizing fertilization. One of the main processes in capacitation involves actin polymerization, and the resulting F-actin is subsequently dispersed prior to the acrosome reaction. Several biochemical reactions that occur during sperm capacitation, including actin polymerization, protect sperm from sAR. In the present review, we describe the protective mechanisms that regulate sperm capacitation and prevent sAR.
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Affiliation(s)
- Haim Breitbart
- The Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 5290002, Israel
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4
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Bowker Z, Goldstein S, Breitbart H. Protein acetylation protects sperm from spontaneous acrosome reaction. Theriogenology 2022; 191:231-238. [PMID: 35998406 DOI: 10.1016/j.theriogenology.2022.08.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Revised: 07/27/2022] [Accepted: 08/03/2022] [Indexed: 10/15/2022]
Abstract
In order to penetrate the egg, spermatozoa must undergo the acrosome reaction in close proximity to the egg. This process can take place only after a series of biochemical changes in the sperm, collectively termed capacitation, occur in the female reproductive tract. Sperm cells can undergo spontaneous-acrosome reaction(sAR) before reaching the vicinity of the egg, preventing successful fertilization. Several mechanisms were shown to protect sperm from undergoing sAR, and all of them are involved in proper capacitation. Here, we describe the involvement of protein acetylation in the mechanism that protects bovine spermatozoa from sAR. Incubation of bovine sperm under non-capacitation conditions revealed a strong increase in sAR that was significantly reduced in the presence of deacetylase inhibitors. Protein kinase A (PKA) is an essential key enzyme in sperm capacitation, and its inhibition results in high sAR. The reduction in sAR by hyperacetylation was independent of PKA activity. We previously demonstrated that calmodulin-kinase II (CaMKII) activity protects sperm from sAR, and here we show that its activity is essential for reduction in sAR by hyperacetylation. We further show that the 'exchange protein directly activated by Camp' (EPAC) mediates both protein lysine acetylation and the reduced rate of sAR caused by hyperacetylation. In conclusion, these results suggest a PKA-independent and EPAC-CaMKII dependent hyperacetylation mechanism that protects sperm from sAR.
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Affiliation(s)
- Z Bowker
- The Mina & Everard Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, 5290002, Israel
| | - S Goldstein
- The Mina & Everard Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, 5290002, Israel
| | - H Breitbart
- The Mina & Everard Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, 5290002, Israel.
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5
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Zhao Y, Lykov N, Tzeng C. Talin‑1 interaction network in cellular mechanotransduction (Review). Int J Mol Med 2022; 49:60. [PMID: 35266014 PMCID: PMC8930095 DOI: 10.3892/ijmm.2022.5116] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Accepted: 02/23/2022] [Indexed: 11/16/2022] Open
Abstract
The mechanical signals within the extracellular matrix (ECM) regulate cell growth, proliferation and differentiation, and integrins function as the hub between the ECM and cellular actin. Focal adhesions (FAs) are multi‑protein, integrin‑containing complexes, acting as tension‑sensing anchoring points that bond cells to the extracellular microenvironment. Talin‑1 serves as the central protein of FAs that participates in the activation of integrins and connects them with the actin cytoskeleton. As a cytoplasmic protein, Talin‑1 consists of a globular head domain and a long rod comprised of a series of α‑helical bundles. The unique structure of the Talin‑1 rod domain permits folding and unfolding in response to the mechanical stress, revealing various binding sites. Thus, conformation changes of the Talin‑1 rod domain enable the cell to convert mechanical signals into chemical through multiple signaling pathways. The present review discusses the binding partners of Talin‑1, their interactions, effects on the cellular processes, and their possible roles in diseases.
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Affiliation(s)
- Ye Zhao
- School of Pharmaceutical Sciences, Nanjing Tech University, Nanjing, Jiangsu 211800, P.R. China
| | - Nikita Lykov
- School of Pharmaceutical Sciences, Nanjing Tech University, Nanjing, Jiangsu 211800, P.R. China
| | - Chimeng Tzeng
- Translational Medicine Research Center-Key Laboratory for Cancer T-Cell Theragnostic and Clinical Translation, School of Pharmaceutical Sciences, Xiamen University, Xiamen, Fujian 361005, P.R. China
- Xiamen Chang Gung Hospital Medical Research Center, Xiamen, Fujian 361005, P.R. China
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6
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Nasif D, Real S, Roqué M, Branham MT. CDC42 as an epigenetic regulator of ID4 in triple-negative breast tumors. Breast Cancer 2022; 29:562-573. [DOI: 10.1007/s12282-022-01334-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Accepted: 01/09/2022] [Indexed: 12/01/2022]
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7
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New C, Lee ZY, Tan KS, Wong AHP, Wang DY, Tran T. Tetraspanins: Host Factors in Viral Infections. Int J Mol Sci 2021; 22:11609. [PMID: 34769038 PMCID: PMC8583825 DOI: 10.3390/ijms222111609] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Revised: 10/22/2021] [Accepted: 10/23/2021] [Indexed: 12/17/2022] Open
Abstract
Tetraspanins are transmembrane glycoproteins that have been shown increasing interest as host factors in infectious diseases. In particular, they were implicated in the pathogenesis of both non-enveloped (human papillomavirus (HPV)) and enveloped (human immunodeficiency virus (HIV), Zika, influenza A virus, (IAV), and coronavirus) viruses through multiple stages of infection, from the initial cell membrane attachment to the syncytium formation and viral particle release. However, the mechanisms by which different tetraspanins mediate their effects vary. This review aimed to compare and contrast the role of tetraspanins in the life cycles of HPV, HIV, Zika, IAV, and coronavirus viruses, which cause the most significant health and economic burdens to society. In doing so, a better understanding of the relative contribution of tetraspanins in virus infection will allow for a more targeted approach in the treatment of these diseases.
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Affiliation(s)
- ChihSheng New
- Infectious Disease Translational Research Program, National University of Singapore, Singapore 119228, Singapore; (C.N.); (Z.-Y.L.); (K.S.T.); (A.H.-P.W.)
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117593, Singapore
| | - Zhao-Yong Lee
- Infectious Disease Translational Research Program, National University of Singapore, Singapore 119228, Singapore; (C.N.); (Z.-Y.L.); (K.S.T.); (A.H.-P.W.)
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117593, Singapore
| | - Kai Sen Tan
- Infectious Disease Translational Research Program, National University of Singapore, Singapore 119228, Singapore; (C.N.); (Z.-Y.L.); (K.S.T.); (A.H.-P.W.)
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117545, Singapore
- Department of Otolaryngology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119228, Singapore
- Biosafety Level 3 Core Facility, Yong Loo Lin School of Medicine, National University Health System, National University of Singapore, Singapore 119228, Singapore
| | - Amanda Huee-Ping Wong
- Infectious Disease Translational Research Program, National University of Singapore, Singapore 119228, Singapore; (C.N.); (Z.-Y.L.); (K.S.T.); (A.H.-P.W.)
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117593, Singapore
| | - De Yun Wang
- Infectious Disease Translational Research Program, National University of Singapore, Singapore 119228, Singapore; (C.N.); (Z.-Y.L.); (K.S.T.); (A.H.-P.W.)
- Department of Otolaryngology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119228, Singapore
| | - Thai Tran
- Infectious Disease Translational Research Program, National University of Singapore, Singapore 119228, Singapore; (C.N.); (Z.-Y.L.); (K.S.T.); (A.H.-P.W.)
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117593, Singapore
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8
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Reynoso S, Castillo V, Katkar GD, Lopez-Sanchez I, Taheri S, Espinoza C, Rohena C, Sahoo D, Gagneux P, Ghosh P. GIV/Girdin, a non-receptor modulator for Gαi/s, regulates spatiotemporal signaling during sperm capacitation and is required for male fertility. eLife 2021; 10:69160. [PMID: 34409938 PMCID: PMC8376251 DOI: 10.7554/elife.69160] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Accepted: 08/05/2021] [Indexed: 12/25/2022] Open
Abstract
For a sperm to successfully fertilize an egg, it must first undergo capacitation in the female reproductive tract and later undergo acrosomal reaction (AR) upon encountering an egg surrounded by its vestment. How premature AR is avoided despite rapid surges in signaling cascades during capacitation remains unknown. Using a combination of conditional knockout (cKO) mice and cell-penetrating peptides, we show that GIV (CCDC88A), a guanine nucleotide-exchange modulator (GEM) for trimeric GTPases, is highly expressed in spermatocytes and is required for male fertility. GIV is rapidly phosphoregulated on key tyrosine and serine residues in human and murine spermatozoa. These phosphomodifications enable GIV-GEM to orchestrate two distinct compartmentalized signaling programs in the sperm tail and head; in the tail, GIV enhances PI3K→Akt signals, sperm motility and survival, whereas in the head it inhibits cAMP surge and premature AR. Furthermore, GIV transcripts are downregulated in the testis and semen of infertile men. These findings exemplify the spatiotemporally segregated signaling programs that support sperm capacitation and shed light on a hitherto unforeseen cause of infertility in men.
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Affiliation(s)
- Sequoyah Reynoso
- Department of Pathology, School of Medicine, University of California San Diego, San Diego, United States
| | - Vanessa Castillo
- Department of Cellular and Molecular Medicine, School of Medicine, University of California San Diego, San Diego, United States
| | - Gajanan Dattatray Katkar
- Department of Cellular and Molecular Medicine, School of Medicine, University of California San Diego, San Diego, United States
| | - Inmaculada Lopez-Sanchez
- Department of Medicine, School of Medicine, University of California San Diego, San Diego, United States
| | - Sahar Taheri
- Department of Computer Science and Engineering, Jacob's School of Engineering, University of California San Diego, San Diego, United States
| | - Celia Espinoza
- Department of Cellular and Molecular Medicine, School of Medicine, University of California San Diego, San Diego, United States
| | - Cristina Rohena
- Department of Cellular and Molecular Medicine, School of Medicine, University of California San Diego, San Diego, United States
| | - Debashis Sahoo
- Department of Computer Science and Engineering, Jacob's School of Engineering, University of California San Diego, San Diego, United States.,Moore's Comprehensive Cancer Center, University of California San Diego, San Diego, United States.,Department of Pediatrics, School of Medicine, University of California San Diego, San Diego, United States
| | - Pascal Gagneux
- Department of Pathology, School of Medicine, University of California San Diego, San Diego, United States
| | - Pradipta Ghosh
- Department of Cellular and Molecular Medicine, School of Medicine, University of California San Diego, San Diego, United States.,Department of Medicine, School of Medicine, University of California San Diego, San Diego, United States.,Moore's Comprehensive Cancer Center, University of California San Diego, San Diego, United States.,Veterans Affairs Medical Center, Washington DC, United States
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9
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Shan MM, Sun SC. The multiple roles of RAB GTPases in female and male meiosis. Hum Reprod Update 2021; 27:1013-1029. [PMID: 34227671 DOI: 10.1093/humupd/dmab019] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Revised: 05/06/2021] [Indexed: 12/27/2022] Open
Abstract
BACKGROUND RAB GTPases constitute the largest family of small GTPases and are found in all eukaryotes. RAB GTPases regulate components of the endomembrane system, the nucleus and the plasma membrane, and are involved in intracellular actin/tubulin-dependent vesicle movement, membrane fusion and cell growth in mitosis. OBJECTIVE AND RATIONALE RAB GTPases play multiple critical roles during both female and male meiosis. This review summarizes the progress made in our understanding of the role of RAB GTPases in female and male meiosis in different species. We also discuss the potential relationship between RAB GTPases and oocyte/sperm quality, which may help in understanding the mechanisms underlying oogenesis and spermatogenesis and potential genetic causes of infertility. SEARCH METHODS The PubMed database was searched for articles published between 1991 and 2020 using the following terms: 'RAB', 'RAB oocyte', 'RAB sperm' and 'RAB meiosis'. OUTCOMES An analysis of 126 relevant articles indicated that RAB GTPases are present in all eukaryotes, and ten subfamilies (almost 70 members) are expressed in human cells. The roles of 25 RAB proteins and orthologues in female meiosis and 12 in male meiosis have been reported. RAB proteins are essential for the accurate continuity of genetic material, successful fertilization and the normal growth of offspring. Distinct and crucial functions of RAB GTPases in meiosis have been reported. In oocytes, RAB GTPases are involved in spindle organization, kinetochore-microtubule attachment, chromosome alignment, actin filament-mediated spindle migration, cytokinesis, cell cycle and oocyte-embryo transition. RAB GTPases function in mitochondrial processes and Golgi-mediated vesicular transport during female meiosis, and are critical for cortical granule transport during fertilization and oocyte-embryo transition. In sperm, RAB GTPases are vital for cytoskeletal organization and successful cytokinesis, and are associated with Golgi-mediated acrosome formation, membrane trafficking and morphological changes of sperm cells, as well as the exocytosis-related acrosome reaction and zona reaction during fertilization. WIDER IMPLICATIONS Abnormal expression of RAB GTPases disrupts intracellular systems, which may induce diverse diseases. The roles of RAB proteins in female and male reproductive systems, thus, need to be considered. The mechanisms underlying the function of RAB GTPases and the binding specificity of their effectors during oogenesis, spermatogenesis and fertilization remain to be studied. This review should contribute to our understanding of the molecular mechanisms of oogenesis and spermatogenesis and potential genetic causes of infertility.
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Affiliation(s)
- Meng-Meng Shan
- College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, China
| | - Shao-Chen Sun
- College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, China
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10
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Suhaiman L, Altamirano KN, Morales A, Belmonte SA. Different Approaches to Record Human Sperm Exocytosis. Methods Mol Biol 2021; 2233:139-168. [PMID: 33222133 DOI: 10.1007/978-1-0716-1044-2_10] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/03/2023]
Abstract
Acrosome reaction is an exocytic process that enables a sperm to penetrate the zona pellucida and fertilize an egg. The process involves the fenestration and vesiculation of the sperm plasma membrane and outer acrosomal membrane, releasing the acrosomal content. Given the importance of the acrosome secretion in fertilization, many different methods have been developed to detect the acrosome reaction of sperm. In this chapter, we describe detailed practical procedures to assess the acrosomal status of human spermatozoa. To do this, we resorted to light optical and epifluorescence microscopy, flow cytometry, and transmission electron microscopy. We also itemize the protocol for real-time measurements of the acrosome reaction by confocal microscopy. Further, we discuss the level of complexity, costs, and the reasons why a researcher should choose each technique.This chapter is designed to provide the user with sufficient background to measure acrosomal exocytosis in human sperm.
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Affiliation(s)
- Laila Suhaiman
- Instituto Interdisciplinario de Ciencias Básicas (ICB) CONICET. Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Cuyo, Mendoza, Argentina
| | - Karina Noel Altamirano
- Instituto de Histología y Embriología de Mendoza (IHEM) "Dr. Mario H. Burgos". CONICET. Facultad de Ciencias Médicas, Universidad Nacional de Cuyo, Mendoza, Argentina
| | - Alfonsina Morales
- Instituto de Histología y Embriología de Mendoza (IHEM) "Dr. Mario H. Burgos". CONICET. Facultad de Ciencias Médicas, Universidad Nacional de Cuyo, Mendoza, Argentina
| | - Silvia Alejandra Belmonte
- Instituto de Histología y Embriología de Mendoza (IHEM) "Dr. Mario H. Burgos". CONICET. Facultad de Ciencias Médicas, Universidad Nacional de Cuyo, Mendoza, Argentina.
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11
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Mata-Martínez E, Sánchez-Tusie AA, Darszon A, Mayorga LS, Treviño CL, De Blas GA. Epac activation induces an extracellular Ca 2+ -independent Ca 2+ wave that triggers acrosome reaction in human spermatozoa. Andrology 2021; 9:1227-1241. [PMID: 33609309 DOI: 10.1111/andr.12989] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Revised: 02/10/2021] [Accepted: 02/17/2021] [Indexed: 01/02/2023]
Abstract
BACKGROUND The signaling pathways of the intracellular second messengers cAMP and Ca2+ play a crucial role in numerous physiological processes in human spermatozoa. One such process is the acrosome reaction (AR), which is necessary for spermatozoa to traverse the egg envelope and to expose a fusogenic membrane allowing the egg-sperm fusion. Progesterone and zona pellucida elicit an intracellular Ca2+ increase that is needed for the AR in the mammalian spermatozoa. This increase is mediated by an initial Ca2+ influx but also by a release from intracellular Ca2+ stores. It is known that intracellular Ca2+ stores play a central role in the regulation of [Ca2+ ]i and in the generation of complex Ca2+ signals such as oscillations and waves. In the human spermatozoa, it has been proposed that the cAMP analog and specific agonist of Epac 8-(p-chlorophenylthio)-2'-O-methyladenosine-3',5'-cyclic monophosphate (2'-O-Me-cAMP) elicits an intracellular Ca2+ release involved in the AR. OBJECTIVE To identify the molecular entities involved in the Ca2+ mobilization triggered by 2'-O-Me-cAMP in human spermatozoa. MATERIALS AND METHODS In capacitated human spermatozoa, we monitored Ca2+ dynamics and the occurrence of the AR in real time using Fluo 3-AM and FM4-64 in a Ca2+ -free medium. RESULTS Epac activation by 2'-O-Me-cAMP induced a Ca2+ wave that started in the midpiece and propagated to the acrosome region. This Ca2+ response was sensitive to rotenone, CGP, xestospongin, NED-19, and thapsigargin, suggesting the participation of different ion transporters (mitochondrial complex I and Na+ /Ca2+ exchanger, inositol 3-phosphate receptors, two-pore channels and internal store Ca2+ -ATPases). DISCUSSION Our results suggest that Epac activation promotes a dynamic crosstalk between three different intracellular Ca2+ stores: the mitochondria, the redundant nuclear envelope, and the acrosome. CONCLUSION The Ca2+ wave triggered by Epac activation is necessary to induce the AR and to enhance the flagellar beat.
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Affiliation(s)
- Esperanza Mata-Martínez
- Laboratorio de Fusión de Membranas y Exocitosis Acrosomal, Instituto de Histología y Embriología Dr. Mario H. Burgos (IHEM), Universidad Nacional de Cuyo, CONICET, Mendoza, Argentina
| | - Ana Alicia Sánchez-Tusie
- Laboratorio de Fisiología Celular y Molecular, Departamento de Investigación Biomédica, Facultad de Medicina, Universidad Autónoma de Querétaro, México
| | - Alberto Darszon
- Instituto de Biotecnología, Universidad Nacional Autónoma de México, Morelos, México
| | - Luis S Mayorga
- Laboratorio de Fusión de Membranas y Exocitosis Acrosomal, Instituto de Histología y Embriología Dr. Mario H. Burgos (IHEM), Universidad Nacional de Cuyo, CONICET, Mendoza, Argentina.,Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Cuyo, Mendoza, Argentina
| | - Claudia L Treviño
- Instituto de Biotecnología, Universidad Nacional Autónoma de México, Morelos, México
| | - Gerardo A De Blas
- Laboratorio de Fusión de Membranas y Exocitosis Acrosomal, Instituto de Histología y Embriología Dr. Mario H. Burgos (IHEM), Universidad Nacional de Cuyo, CONICET, Mendoza, Argentina.,Laboratorio de Teleanálisis e Investigación Traslacional, Área Farmacología, Facultad de Ciencias Médicas, Universidad Nacional de Cuyo, Mendoza, Argentina
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12
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Baro Graf C, Ritagliati C, Stival C, Luque GM, Gentile I, Buffone MG, Krapf D. Everything you ever wanted to know about PKA regulation and its involvement in mammalian sperm capacitation. Mol Cell Endocrinol 2020; 518:110992. [PMID: 32853743 DOI: 10.1016/j.mce.2020.110992] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Revised: 08/11/2020] [Accepted: 08/12/2020] [Indexed: 12/29/2022]
Abstract
The 3', 5'-cyclic adenosine monophosphate (cAMP) dependent protein kinase (PKA) is a tetrameric holoenzyme comprising a set of two regulatory subunits (PKA-R) and two catalytic (PKA-C) subunits. The PKA-R subunits act as sensors of cAMP and allow PKA-C activity. One of the first signaling events observed during mammalian sperm capacitation is PKA activation. Thus, understanding how PKA activity is restricted in space and time is crucial to decipher the critical steps of sperm capacitation. It is widely accepted that PKA specificity depends on several levels of regulation. Anchoring proteins play a pivotal role in achieving proper localization signaling, subcellular targeting and cAMP microdomains. These multi-factorial regulation steps are necessary for a precise spatio-temporal activation of PKA. Here we discuss recent understanding of regulatory mechanisms of PKA in mammalian sperm, such as post-translational modifications, in the context of its role as the master orchestrator of molecular events conducive to capacitation.
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Affiliation(s)
- Carolina Baro Graf
- Laboratory of Cell Signal Transduction Networks, Instituto de Biología Molecular y Celular de Rosario (IBR), CONICET-UNR, Rosario, Argentina; Laboratorio de Medicina Reproductiva (LMR), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Rosario, Argentina
| | - Carla Ritagliati
- Laboratory of Cell Signal Transduction Networks, Instituto de Biología Molecular y Celular de Rosario (IBR), CONICET-UNR, Rosario, Argentina
| | - Cintia Stival
- Laboratory of Cell Signal Transduction Networks, Instituto de Biología Molecular y Celular de Rosario (IBR), CONICET-UNR, Rosario, Argentina
| | - Guillermina M Luque
- Laboratory of Cellular and Molecular Reproductive Biology, Instituto de Biología y Medicina Experimental (IBYME), CONICET, Buenos Aires, Argentina
| | - Iñaki Gentile
- Laboratory of Cell Signal Transduction Networks, Instituto de Biología Molecular y Celular de Rosario (IBR), CONICET-UNR, Rosario, Argentina
| | - Mariano G Buffone
- Laboratory of Cellular and Molecular Reproductive Biology, Instituto de Biología y Medicina Experimental (IBYME), CONICET, Buenos Aires, Argentina
| | - Dario Krapf
- Laboratory of Cell Signal Transduction Networks, Instituto de Biología Molecular y Celular de Rosario (IBR), CONICET-UNR, Rosario, Argentina; Laboratorio de Medicina Reproductiva (LMR), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Rosario, Argentina.
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13
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Itzhakov D, Nitzan Y, Breitbart H. Protein kinase A inhibition induces EPAC-dependent acrosomal exocytosis in human sperm. Asian J Androl 2020; 21:337-344. [PMID: 30632486 PMCID: PMC6628745 DOI: 10.4103/aja.aja_99_18] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
To interact with the egg, the spermatozoon must undergo several biochemical and motility modifications in the female reproductive tract, collectively called capacitation. Only capacitated sperm can undergo acrosomal exocytosis, near or on the egg, a process that allows the sperm to penetrate and fertilize the egg. In the present study, we investigated the involvement of cyclic adenosine monophosphate (cAMP)-dependent processes on acrosomal exocytosis. Inhibition of protein kinase A (PKA) at the end of capacitation induced acrosomal exocytosis. This process is cAMP-dependent; however, the addition of relatively high concentration of the membrane-permeable 8-bromo-cAMP (8Br-cAMP, 0.1 mmol l−1) analog induced significant inhibition of the acrosomal exocytosis. The induction of acrosomal exocytosis by PKA inhibition was significantly inhibited by an exchange protein directly activated by cAMP (EPAC) ESI09 inhibitor. The EPAC selective substrate activated AE at relatively low concentrations (0.02–0.1 μmol l−1), whereas higher concentrations (>5 μmol l−1) were inhibitory to the AE induced by PKA inhibition. Inhibition of PKA revealed about 50% increase in intracellular cAMP levels, conditions under which EPAC can be activated to induce the AE. Induction of AE by activating the actin severing-protein, gelsolin, which causes F-actin dispersion, was inhibited by the EPAC inhibitor. The AE induced by PKA inhibition was mediated by phospholipase C activity but not by the Ca2+-channel, CatSper. Thus, inhibition of PKA at the end of the capacitation process induced EPAC/phospholipase C-dependent acrosomal exocytosis. EPAC mediates F-actin depolymerization and/or activation of effectors downstream to F-actin breakdown that lead to acrosomal exocytosis.
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Affiliation(s)
- Diana Itzhakov
- The Mina and Everard Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 5290002, Israel
| | - Yeshayahu Nitzan
- Department of Clinical Laboratory Science, Zefat Academic College, Zefat 1320611, Israel
| | - Haim Breitbart
- The Mina and Everard Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 5290002, Israel
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14
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Adrenergic stimulation of adiponectin secretion in visceral mouse adipocytes is blunted in high-fat diet induced obesity. Sci Rep 2019; 9:10680. [PMID: 31337827 PMCID: PMC6650418 DOI: 10.1038/s41598-019-47113-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2019] [Accepted: 07/09/2019] [Indexed: 12/31/2022] Open
Abstract
The hormone adiponectin is secreted by white adipocytes and has been put forward as a key mediator of obesity-linked insulin resistance and the metabolic syndrome. Although adiponectin was discovered two decades ago, the knowledge about the molecular and cellular regulation of its secretion is incomplete. Here we have investigated the adrenergic regulation of adiponectin secretion in primary visceral (gonadal) adipocytes isolated from lean or obese/diabetic mice. We show that visceral adipocyte adiponectin release is triggered by cAMP/catecholamines via signalling pathways involving adrenergic beta-3-receptors (β3ARs) and Exchange Protein directly Activated by cAMP, isoform 1 (Epac1). The adrenergically stimulated adiponectin secretion is blunted in visceral adipocytes isolated from obese and diabetic mice and our results suggest the existence of a secretory defect. We have previously shown that adiponectin secretion in subcutaneous adipocytes is abolished in the obese/diabetic state due to reduced abundance of β3ARs and Epac1. However, here we show that protein levels of β3ARs and Epac1 are maintained in visceral adipocytes from obese/diabetic mice proposing that other molecular defects underlie the blunted adiponectin release. Gene expression analysis indicate diabesity-associated disturbances of the signalling downstream of Epac1 and/or the exocytotic process itself. Our study proposes that visceral adipocytes partake in the regulated secretion of adiponectin and may thus influence circulating levels of the hormone, in health and in metabolic disease.
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15
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Ruete MC, Zarelli VEP, Masone D, de Paola M, Bustos DM, Tomes CN. A connection between reversible tyrosine phosphorylation and SNARE complex disassembly activity of N-ethylmaleimide-sensitive factor unveiled by the phosphomimetic mutant N-ethylmaleimide-sensitive factor-Y83E. ACTA ACUST UNITED AC 2019; 25:344-358. [DOI: 10.1093/molehr/gaz031] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Revised: 05/16/2019] [Accepted: 06/03/2019] [Indexed: 12/26/2022]
Abstract
Abstract
N-ethylmaleimide-sensitive factor (NSF) disassembles fusion-incompetent cis soluble-NSF attachment protein receptor (SNARE) complexes making monomeric SNAREs available for subsequent trans pairing and fusion. In most cells the activity of NSF is constitutive, but in Jurkat cells and sperm it is repressed by tyrosine phosphorylation; the phosphomimetic mutant NSF–Y83E inhibits secretion in the former. The questions addressed here are if and how the NSF mutant influences the configuration of the SNARE complex. Our model is human sperm, where the initiation of exocytosis (acrosome reaction (AR)) de-represses the activity of NSF through protein tyrosine phosphatase 1B (PTP1B)-mediated dephosphorylation. We developed a fluorescence microscopy-based method to show that capacitation increased, and challenging with an AR inducer decreased, the number of cells with tyrosine-phosphorylated PTP1B substrates in the acrosomal domain. Results from bioinformatic and biochemical approaches using purified recombinant proteins revealed that NSF–Y83E bound PTP1B and thereupon inhibited its catalytic activity. Mutant NSF introduced into streptolysin O-permeabilized sperm impaired cis SNARE complex disassembly, blocking the AR; subsequent addition of PTP1B rescued exocytosis. We propose that NSF–Y83E prevents endogenous PTP1B from dephosphorylating sperm NSF, thus maintaining NSF’s activity in a repressed mode and the SNARE complex unable to dissociate. The contribution of this paper to the sperm biology field is the detection of PTP1B substrates, one of them likely being NSF, whose tyrosine phosphorylation status varies during capacitation and the AR. The contribution of this paper to the membrane traffic field is to have generated direct evidence that explains the dominant-negative role of the phosphomimetic mutant NSF–Y83E.
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Affiliation(s)
- María Celeste Ruete
- Instituto de Histología y Embriología de Mendoza Dr Mario H. Burgos–CONICET, Universidad Nacional de Cuyo, Mendoza, Argentina
| | - Valeria Eugenia Paola Zarelli
- Instituto de Histología y Embriología de Mendoza Dr Mario H. Burgos–CONICET, Universidad Nacional de Cuyo, Mendoza, Argentina
- Facultad de Ciencias Médicas, Universidad Nacional de Cuyo, Mendoza, Argentina
| | - Diego Masone
- Instituto de Histología y Embriología de Mendoza Dr Mario H. Burgos–CONICET, Universidad Nacional de Cuyo, Mendoza, Argentina
- Facultad de Ingeniería, Universidad Nacional de Cuyo, Mendoza, Argentina
| | - Matilde de Paola
- Instituto de Histología y Embriología de Mendoza Dr Mario H. Burgos–CONICET, Universidad Nacional de Cuyo, Mendoza, Argentina
- Facultad de Ciencias Médicas, Universidad Nacional de Cuyo, Mendoza, Argentina
- Instituto de Medicina y Biología Experimental de Cuyo–Consejo Nacional de Investigaciones Científicas y Técnicas, Universidad Nacional de Cuyo, Mendoza, Argentina
| | - Diego Martín Bustos
- Instituto de Histología y Embriología de Mendoza Dr Mario H. Burgos–CONICET, Universidad Nacional de Cuyo, Mendoza, Argentina
- Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Cuyo, Mendoza, Argentina
| | - Claudia Nora Tomes
- Instituto de Histología y Embriología de Mendoza Dr Mario H. Burgos–CONICET, Universidad Nacional de Cuyo, Mendoza, Argentina
- Facultad de Ciencias Médicas, Universidad Nacional de Cuyo, Mendoza, Argentina
- Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Cuyo, Mendoza, Argentina
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16
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Alharatani R, Griffin JN, Liu KJ. Expression of the guanine nucleotide exchange factor, RAPGEF5, during mouse and human embryogenesis. Gene Expr Patterns 2019; 34:119057. [PMID: 31163262 DOI: 10.1016/j.gep.2019.119057] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Revised: 04/25/2019] [Accepted: 05/31/2019] [Indexed: 01/19/2023]
Abstract
Rap GTPases mediate fundamental cellular processes, including cell adhesion, migration and intracellular signal transduction. The subcellular activity of these GTPases is regulated by dedicated activators (guanine nucleotide exchange factors, GEFs) and deactivators (GTPase-activating proteins, GAPs). RAPGEF5 is a potent activator of Rap proteins and mutations in RAPGEF5 have been linked to both neurological disorders and congenital heart disease. In the frog model, Xenopus tropicalis, Rapgef5 is a critical regulator of the canonical Wnt signalling pathway and is required for normal gastrulation and correct establishment of the left-right body axis. However, requirements for RAPGEF5 in other developmental contexts, and in mammalian embryogenesis in particular, remain undefined. Here, we describe RAPGEF5 mRNA expression patterns during mouse (E9.5 - E16.5) and human (Carnegie stage 21) development, as an initial step towards better understanding its developmental functions.
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Affiliation(s)
- Reham Alharatani
- The Centre for Craniofacial and Regenerative Biology, Faculty of Dental, Oral and Craniofacial Sciences, King's College London, London, SE1 9RT, UK
| | - John N Griffin
- The Centre for Craniofacial and Regenerative Biology, Faculty of Dental, Oral and Craniofacial Sciences, King's College London, London, SE1 9RT, UK.
| | - Karen J Liu
- The Centre for Craniofacial and Regenerative Biology, Faculty of Dental, Oral and Craniofacial Sciences, King's College London, London, SE1 9RT, UK.
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17
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Quevedo MF, Bustos MA, Masone D, Roggero CM, Bustos DM, Tomes CN. Grab recruitment by Rab27A-Rabphilin3a triggers Rab3A activation in human sperm exocytosis. BIOCHIMICA ET BIOPHYSICA ACTA. MOLECULAR CELL RESEARCH 2019; 1866:612-622. [PMID: 30599141 DOI: 10.1016/j.bbamcr.2018.12.005] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2018] [Revised: 11/30/2018] [Accepted: 12/09/2018] [Indexed: 12/12/2022]
Abstract
Sperm must undergo the regulated exocytosis of its dense core granule (the acrosome reaction, AR) to fertilize the egg. We have previously described that Rabs3 and 27 are organized in a RabGEF cascade within the signaling pathway elicited by exocytosis stimuli in human sperm. Here, we report the identity and the role of two molecules that link these secretory Rabs in the RabGEF cascade: Rabphilin3a and GRAB. Like Rab3 and Rab27, GRAB and Rabphilin3a are present, localize to the acrosomal region and are required for calcium-triggered exocytosis in human sperm. Sequestration of either protein with specific antibodies introduced into streptolysin O-permeabilized sperm impairs the activation of Rab3 in the acrosomal region elicited by calcium, but not that of Rab27. Biochemical and functional assays indicate that Rabphilin3a behaves as a Rab27 effector during the AR and that GRAB exhibits GEF activity toward Rab3A. Recombinant, active Rab27A pulls down Rabphilin3a and GRAB from human sperm extracts. Conversely, immobilized Rabphilin3a recruits Rab27 and GRAB; the latter promotes Rab3A activation. The enzymatic activity of GRAB toward Rab3A was also suggested by in silico and in vitro assays with purified proteins. In summary, we describe here a signaling module where Rab27A-GTP interacts with Rabphilin3a, which in turn recruits a guanine nucleotide-exchange activity toward Rab3A. This is the first description of the interaction of Rabphilin3a with a GEF. Because the machinery that drives exocytosis is highly conserved, it is tempting to hypothesize that the RabGEF cascade unveiled here might be part of the molecular mechanisms that drive exocytosis in other secretory systems.
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Affiliation(s)
- María Florencia Quevedo
- Instituto de Histologia y Embriologia de Mendoza (IHEM) Dr. Mario H. Burgos-CONICET, Universidad Nacional de Cuyo, 5500 Mendoza, Argentina
| | - Matías Alberto Bustos
- Instituto de Histologia y Embriologia de Mendoza (IHEM) Dr. Mario H. Burgos-CONICET, Universidad Nacional de Cuyo, 5500 Mendoza, Argentina
| | - Diego Masone
- Instituto de Histologia y Embriologia de Mendoza (IHEM) Dr. Mario H. Burgos-CONICET, Universidad Nacional de Cuyo, 5500 Mendoza, Argentina; Facultad de Ingeniería, Universidad Nacional de Cuyo, Argentina
| | | | - Diego Martín Bustos
- Instituto de Histologia y Embriologia de Mendoza (IHEM) Dr. Mario H. Burgos-CONICET, Universidad Nacional de Cuyo, 5500 Mendoza, Argentina; Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Cuyo, Argentina
| | - Claudia Nora Tomes
- Instituto de Histologia y Embriologia de Mendoza (IHEM) Dr. Mario H. Burgos-CONICET, Universidad Nacional de Cuyo, 5500 Mendoza, Argentina; Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Cuyo, Argentina; Facultad de Ciencias Médicas, Universidad Nacional de Cuyo, Argentina.
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18
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The cAMP effectors, Rap2b and EPAC, are involved in the regulation of the development of the Coxiella burnetii containing vacuole by altering the fusogenic capacity of the vacuole. PLoS One 2019; 14:e0212202. [PMID: 30763357 PMCID: PMC6375611 DOI: 10.1371/journal.pone.0212202] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Accepted: 01/29/2019] [Indexed: 11/23/2022] Open
Abstract
Cyclic Adenosine 3′,5′-monophosphate (cAMP) is a key second messenger known to directly regulate not only the protein kinase A (PKA) activity but also other important molecules such as the exchange protein activated by cAMP (EPAC), which is as a guanine nucleotide exchange factor (GEF) of the low molecular weight GTPase, Rap2. Coxiella burnetii is a Gram negative bacterium that survives and grows in a large Coxiella replicative vacuole (CRV), which displays lysosomal and autophagic features. In this report, we present evidence that both, EPAC and its downstream effector Rap2b, were recruited to the CRV. The transient over-expression of the Rap2b wt protein, but not its inactive mutant Rap2b ΔAAX, markedly inhibited the development of the large CRV. Additionally, Rap2b wtinhibited the fusion of early Coxiella phagosomes with the fully developed CRV, indicating that homotypic fusion events are altered in the presence of high levels of Rap2b wt. Likewise, the fusion of endosome/lysosomal compartments (heterotypic fusions) with the large CRV was also affected by the over-expression of this GTPase. Interestingly, cell overexpression of Rap2b wt markedly decreased the levels of the v-SNARE, Vamp7, suggesting that this down-regulation impairs the homotypic and heterotypic fusions events of the Coxiella vacuole.
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19
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Romarowski A, Velasco Félix ÁG, Torres Rodríguez P, Gervasi MG, Xu X, Luque GM, Contreras-Jiménez G, Sánchez-Cárdenas C, Ramírez-Gómez HV, Krapf D, Visconti PE, Krapf D, Guerrero A, Darszon A, Buffone MG. Super-resolution imaging of live sperm reveals dynamic changes of the actin cytoskeleton during acrosomal exocytosis. J Cell Sci 2018; 131:jcs.218958. [PMID: 30301778 DOI: 10.1242/jcs.218958] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2018] [Accepted: 09/25/2018] [Indexed: 01/14/2023] Open
Abstract
Filamentous actin (F-actin) is a key factor in exocytosis in many cell types. In mammalian sperm, acrosomal exocytosis (denoted the acrosome reaction or AR), a special type of controlled secretion, is regulated by multiple signaling pathways and the actin cytoskeleton. However, the dynamic changes of the actin cytoskeleton in live sperm are largely not understood. Here, we used the powerful properties of SiR-actin to examine actin dynamics in live mouse sperm at the onset of the AR. By using a combination of super-resolution microscopy techniques to image sperm loaded with SiR-actin or sperm from transgenic mice containing Lifeact-EGFP, six regions containing F-actin within the sperm head were revealed. The proportion of sperm possessing these structures changed upon capacitation. By performing live-cell imaging experiments, we report that dynamic changes of F-actin during the AR occur in specific regions of the sperm head. While certain F-actin regions undergo depolymerization prior to the initiation of the AR, others remain unaltered or are lost after exocytosis occurs. Our work emphasizes the utility of live-cell nanoscopy, which will undoubtedly impact the search for mechanisms that underlie basic sperm functions.This article has an associated First Person interview with the first author of the paper.
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Affiliation(s)
- Ana Romarowski
- Instituto de Biología y Medicina Experimental (IBYME), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires C1428ADN, Argentina
| | - Ángel G Velasco Félix
- Laboratorio Nacional de Microscopía Avanzada, Instituto de Biotecnología, Universidad Nacional Autónoma de México (UNAM), Cuernavaca, Morelos 62210, México
| | - Paulina Torres Rodríguez
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México (UNAM), Cuernavaca, Morelos 62210, México
| | - María G Gervasi
- Department of Veterinary and Animal Science, Paige Labs, University of Massachusetts, Amherst, MA 01003, USA
| | - Xinran Xu
- Department of Electrical and Computer Engineering, School of Biomedical Engineering, 1301 Campus Delivery, Fort Collins, CO 80523, USA
| | - Guillermina M Luque
- Instituto de Biología y Medicina Experimental (IBYME), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires C1428ADN, Argentina
| | - Gastón Contreras-Jiménez
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México (UNAM), Cuernavaca, Morelos 62210, México
| | - Claudia Sánchez-Cárdenas
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México (UNAM), Cuernavaca, Morelos 62210, México
| | - Héctor V Ramírez-Gómez
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México (UNAM), Cuernavaca, Morelos 62210, México
| | - Diego Krapf
- Department of Electrical and Computer Engineering, School of Biomedical Engineering, 1301 Campus Delivery, Fort Collins, CO 80523, USA
| | - Pablo E Visconti
- Department of Veterinary and Animal Science, Paige Labs, University of Massachusetts, Amherst, MA 01003, USA
| | - Dario Krapf
- Instituto de Biología Molecular y Celular de Rosario (CONICET-UNR), Rosario, Santa Fe S2000EZP, Argentina
| | - Adán Guerrero
- Laboratorio Nacional de Microscopía Avanzada, Instituto de Biotecnología, Universidad Nacional Autónoma de México (UNAM), Cuernavaca, Morelos 62210, México
| | - Alberto Darszon
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México (UNAM), Cuernavaca, Morelos 62210, México
| | - Mariano G Buffone
- Instituto de Biología y Medicina Experimental (IBYME), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires C1428ADN, Argentina
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20
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Puga Molina LC, Luque GM, Balestrini PA, Marín-Briggiler CI, Romarowski A, Buffone MG. Molecular Basis of Human Sperm Capacitation. Front Cell Dev Biol 2018; 6:72. [PMID: 30105226 PMCID: PMC6078053 DOI: 10.3389/fcell.2018.00072] [Citation(s) in RCA: 135] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Accepted: 06/19/2018] [Indexed: 12/31/2022] Open
Abstract
In the early 1950s, Austin and Chang independently described the changes that are required for the sperm to fertilize oocytes in vivo. These changes were originally grouped under name of “capacitation” and were the first step in the development of in vitro fertilization (IVF) in humans. Following these initial and fundamental findings, a remarkable number of observations led to characterization of the molecular steps behind this process. The discovery of certain sperm-specific molecules and the possibility to record ion currents through patch-clamp approaches helped to integrate the initial biochemical observation with the activity of ion channels. This is of particular importance in the male gamete due to the fact that sperm are transcriptionally inactive. Therefore, sperm must control all these changes that occur during their transit through the male and female reproductive tracts by complex signaling cascades that include post-translational modifications. This review is focused on the principal molecular mechanisms that govern human sperm capacitation with particular emphasis on comparing all the reported pieces of evidence with the mouse model.
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Affiliation(s)
- Lis C Puga Molina
- Instituto de Biología y Medicina Experimental, Consejo Nacional de Investigaciones Científicas y Tecnológicas, Buenos Aires, Argentina
| | - Guillermina M Luque
- Instituto de Biología y Medicina Experimental, Consejo Nacional de Investigaciones Científicas y Tecnológicas, Buenos Aires, Argentina
| | - Paula A Balestrini
- Instituto de Biología y Medicina Experimental, Consejo Nacional de Investigaciones Científicas y Tecnológicas, Buenos Aires, Argentina
| | - Clara I Marín-Briggiler
- Instituto de Biología y Medicina Experimental, Consejo Nacional de Investigaciones Científicas y Tecnológicas, Buenos Aires, Argentina
| | - Ana Romarowski
- Instituto de Biología y Medicina Experimental, Consejo Nacional de Investigaciones Científicas y Tecnológicas, Buenos Aires, Argentina
| | - Mariano G Buffone
- Instituto de Biología y Medicina Experimental, Consejo Nacional de Investigaciones Científicas y Tecnológicas, Buenos Aires, Argentina
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21
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Balbach M, Beckert V, Hansen JN, Wachten D. Shedding light on the role of cAMP in mammalian sperm physiology. Mol Cell Endocrinol 2018; 468:111-120. [PMID: 29146556 DOI: 10.1016/j.mce.2017.11.008] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/21/2017] [Revised: 11/10/2017] [Accepted: 11/10/2017] [Indexed: 12/24/2022]
Abstract
Mammalian fertilization relies on sperm finding the egg and penetrating the egg vestments. All steps in a sperm's lifetime crucially rely on changes in the second messenger cAMP (cyclic adenosine monophosphate). In recent years, it has become clear that signal transduction in sperm is not a continuum, but rather organized in subcellular domains, e.g. the sperm head and the sperm flagellum, with the latter being further separated into the midpiece, principal piece, and endpiece. To understand the underlying signaling pathways controlling sperm function in more detail, experimental approaches are needed that allow to study sperm signaling with spatial and temporal precision. Here, we will give a comprehensive overview on cAMP signaling in mammalian sperm, describing the molecular players involved in these pathways and the sperm functions that are controlled by cAMP. Furthermore, we will highlight recent advances in analyzing and manipulating sperm signaling with spatio-temporal precision using light.
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Affiliation(s)
- Melanie Balbach
- Center of Advanced European Studies and Research (caesar), Department of Molecular Sensory Systems, Bonn, Germany
| | - Vera Beckert
- Institute of Innate Immunity, University Hospital, University of Bonn, Bonn, Germany
| | - Jan N Hansen
- Institute of Innate Immunity, University Hospital, University of Bonn, Bonn, Germany
| | - Dagmar Wachten
- Institute of Innate Immunity, University Hospital, University of Bonn, Bonn, Germany; Center of Advanced European Studies and Research (caesar), Minerva Max Planck Research Group, Molecular Physiology, Bonn, Germany.
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22
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Wiggins SV, Steegborn C, Levin LR, Buck J. Pharmacological modulation of the CO 2/HCO 3-/pH-, calcium-, and ATP-sensing soluble adenylyl cyclase. Pharmacol Ther 2018; 190:173-186. [PMID: 29807057 DOI: 10.1016/j.pharmthera.2018.05.008] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Cyclic AMP (cAMP), the prototypical second messenger, has been implicated in a wide variety of (often opposing) physiological processes. It simultaneously mediates multiple, diverse processes, often within a single cell, by acting locally within independently-regulated and spatially-restricted microdomains. Within each microdomain, the level of cAMP will be dependent upon the balance between its synthesis by adenylyl cyclases and its degradation by phosphodiesterases (PDEs). In mammalian cells, there are many PDE isoforms and two types of adenylyl cyclases; the G protein regulated transmembrane adenylyl cyclases (tmACs) and the CO2/HCO3-/pH-, calcium-, and ATP-sensing soluble adenylyl cyclase (sAC). Discriminating the roles of individual cyclic nucleotide microdomains requires pharmacological modulators selective for the various PDEs and/or adenylyl cyclases. Such tools present an opportunity to develop therapeutics specifically targeted to individual cAMP dependent pathways. The pharmacological modulators of tmACs have recently been reviewed, and in this review, we describe the current status of pharmacological tools available for studying sAC.
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Affiliation(s)
- Shakarr V Wiggins
- Graduate Program in Neuroscience, Weill Cornell Medicine, New York, NY 10065, United States
| | - Clemens Steegborn
- Department of Biochemistry, University of Bayreuth, 95440 Bayreuth, Germany
| | - Lonny R Levin
- Department of Pharmacology, Weill Cornell Medicine, New York, NY 10065, United States.
| | - Jochen Buck
- Department of Pharmacology, Weill Cornell Medicine, New York, NY 10065, United States
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23
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Zhang L, Zhang L, Liu H, Jiang F, Wang H, Li D, Gao R. Inhibition of Epac2 Attenuates Neural Cell Apoptosis and Improves Neurological Deficits in a Rat Model of Traumatic Brain Injury. Front Neurosci 2018; 12:263. [PMID: 29740274 PMCID: PMC5924794 DOI: 10.3389/fnins.2018.00263] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2018] [Accepted: 04/05/2018] [Indexed: 11/13/2022] Open
Abstract
Traumatic brain injury (TBI) is a major cause of mortality and disability worldwide. TBI-induced neuronal apoptosis is one of the main contributors to the secondary injury process. The aim of this study is to investigate the involvement of Exchange protein directly activated by cAMP 2 (Epac2) on TBI. We found that the expression level of Epac2 surrounding the injured area of brain in rats of TBI model was significantly increased at 12 h after TBI. The role of Epac2 in TBI was further explored by using a selective Epac2 antagonist ESI-05 to decrease the Epac2 expression. We discovered that inhibition of Epac2 could improve the neurological impairment and attenuate brain edema following TBI. The Epac2 inhibition effectively reduced neuronal cell death and P38 MAPK signaling pathway may be involved in this process. Our results suggest that inhibition of Epac2 may be a potential therapy for TBI by reducing the neural cell death, alleviating brain edema and improving neurologic deficits.
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Affiliation(s)
- Ling Zhang
- Translational Medicine Center, The First People's Hospital of Zhangjiagang, Zhangjiagang, China.,Department of Neurosurgery, The First People's Hospital of Zhangjiagang, Zhangjiagang, China
| | - Li Zhang
- Department of Neurosurgery, The First People's Hospital of Zhangjiagang, Zhangjiagang, China
| | - Huixiang Liu
- Department of Neurosurgery, The First People's Hospital of Zhangjiagang, Zhangjiagang, China
| | - Feng Jiang
- Department of Neurosurgery, The First People's Hospital of Zhangjiagang, Zhangjiagang, China
| | - Huanjing Wang
- Department of Neurosurgery, Zhangjiagang Hospital of Traditional Chinese Medicine, Zhangjiagang, China
| | - Di Li
- Translational Medicine Center, The First People's Hospital of Zhangjiagang, Zhangjiagang, China
| | - Rong Gao
- Department of Neurosurgery, The First People's Hospital of Zhangjiagang, Zhangjiagang, China
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24
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Sequera C, Manzano S, Guerrero C, Porras A. How Rap and its GEFs control liver physiology and cancer development. C3G alterations in human hepatocarcinoma. Hepat Oncol 2018; 5:HEP05. [PMID: 30302196 PMCID: PMC6168044 DOI: 10.2217/hep-2017-0026] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Accepted: 03/20/2018] [Indexed: 02/08/2023] Open
Abstract
Rap proteins regulate liver physiopathology. For example, Rap2B promotes hepatocarcinoma (HCC) growth, while Rap1 might play a dual role. The RapGEF, Epac1, activates Rap upon cAMP binding, regulating metabolism, survival, and liver regeneration. A liver specific Epac2 isoform lacking cAMP-binding domain also activates Rap1, promoting fibrosis in alcoholic liver disease. C3G (RapGEF1) is also present in the liver, but mainly as shorter isoforms. Its function in the liver remains unknown. Information from different public genetic databases revealed that C3G mRNA levels increase in HCC, although they decrease in metastatic stages. In addition, several mutations in RapGEF1 gene are present, associated with a reduced patient survival. Based on this, C3G might represent a new HCC diagnostic and prognostic marker, and a therapeutic target.
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Affiliation(s)
- Celia Sequera
- Departamento de Bioquímica y Biología Molecular, Facultad de Farmacia, Universidad Complutense de Madrid, Madrid, Spain.,Instituto de Investigación Sanitaria del Hospital Clínico San Carlos (IdISSC), Madrid, Spain.,Departamento de Bioquímica y Biología Molecular, Facultad de Farmacia, Universidad Complutense de Madrid, Madrid, Spain.,Instituto de Investigación Sanitaria del Hospital Clínico San Carlos (IdISSC), Madrid, Spain
| | - Sara Manzano
- Departamento de Bioquímica y Biología Molecular, Facultad de Farmacia, Universidad Complutense de Madrid, Madrid, Spain.,Instituto de Investigación Sanitaria del Hospital Clínico San Carlos (IdISSC), Madrid, Spain.,Departamento de Bioquímica y Biología Molecular, Facultad de Farmacia, Universidad Complutense de Madrid, Madrid, Spain.,Instituto de Investigación Sanitaria del Hospital Clínico San Carlos (IdISSC), Madrid, Spain
| | - Carmen Guerrero
- Instituto de Biología Molecular y Celular del Cáncer, USAL-CSIC, Salamanca, Spain.,Instituto de Investigación Biomédica de Salamanca (IBSAL), Salamanca, Spain.,Departamento de Medicina, Universidad de Salamanca, Salamanca, Spain.,Instituto de Biología Molecular y Celular del Cáncer, USAL-CSIC, Salamanca, Spain.,Instituto de Investigación Biomédica de Salamanca (IBSAL), Salamanca, Spain.,Departamento de Medicina, Universidad de Salamanca, Salamanca, Spain
| | - Almudena Porras
- Departamento de Bioquímica y Biología Molecular, Facultad de Farmacia, Universidad Complutense de Madrid, Madrid, Spain.,Instituto de Investigación Sanitaria del Hospital Clínico San Carlos (IdISSC), Madrid, Spain.,Departamento de Bioquímica y Biología Molecular, Facultad de Farmacia, Universidad Complutense de Madrid, Madrid, Spain.,Instituto de Investigación Sanitaria del Hospital Clínico San Carlos (IdISSC), Madrid, Spain
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25
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Robichaux WG, Cheng X. Intracellular cAMP Sensor EPAC: Physiology, Pathophysiology, and Therapeutics Development. Physiol Rev 2018; 98:919-1053. [PMID: 29537337 PMCID: PMC6050347 DOI: 10.1152/physrev.00025.2017] [Citation(s) in RCA: 138] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Revised: 09/05/2017] [Accepted: 09/06/2017] [Indexed: 12/13/2022] Open
Abstract
This review focuses on one family of the known cAMP receptors, the exchange proteins directly activated by cAMP (EPACs), also known as the cAMP-regulated guanine nucleotide exchange factors (cAMP-GEFs). Although EPAC proteins are fairly new additions to the growing list of cAMP effectors, and relatively "young" in the cAMP discovery timeline, the significance of an EPAC presence in different cell systems is extraordinary. The study of EPACs has considerably expanded the diversity and adaptive nature of cAMP signaling associated with numerous physiological and pathophysiological responses. This review comprehensively covers EPAC protein functions at the molecular, cellular, physiological, and pathophysiological levels; and in turn, the applications of employing EPAC-based biosensors as detection tools for dissecting cAMP signaling and the implications for targeting EPAC proteins for therapeutic development are also discussed.
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Affiliation(s)
- William G Robichaux
- Department of Integrative Biology and Pharmacology, Texas Therapeutics Institute, The Brown Foundation Institute of Molecular Medicine, The University of Texas Health Science Center , Houston, Texas
| | - Xiaodong Cheng
- Department of Integrative Biology and Pharmacology, Texas Therapeutics Institute, The Brown Foundation Institute of Molecular Medicine, The University of Texas Health Science Center , Houston, Texas
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26
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Schuhmacher B, Rengstl B, Döring C, Bein J, Newrzela S, Brunnberg U, Kvasnicka HM, Vornanen M, Küppers R, Hansmann ML, Hartmann S. A strong host response and lack of MYC expression are characteristic for diffuse large B cell lymphoma transformed from nodular lymphocyte predominant Hodgkin lymphoma. Oncotarget 2018; 7:72197-72210. [PMID: 27708232 PMCID: PMC5342154 DOI: 10.18632/oncotarget.12363] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2016] [Accepted: 09/19/2016] [Indexed: 12/29/2022] Open
Abstract
Nodular lymphocyte predominant Hodgkin lymphoma (NLPHL) is an indolent lymphoma, but can transform into diffuse large B cell lymphoma (DLBCL), showing a more aggressive clinical behavior. Little is known about these cases on the molecular level. Therefore, the aim of the present study was to characterize DLBCL transformed from NLPHL (LP-DLBCL) by gene expression profiling (GEP). GEP revealed an inflammatory signature pinpointing to a specific host response. In a coculture model resembling this host response, DEV tumor cells showed an impaired growth behavior. Mechanisms involved in the reduced tumor cell proliferation included a downregulation of MYC and its target genes. Lack of MYC expression was also confirmed in 12/16 LP-DLBCL by immunohistochemistry. Furthermore, CD274/PD-L1 was upregulated in DEV tumor cells after coculture with T cells or monocytes and its expression was validated in 12/19 cases of LP-DLBCL. Thereby, our data provide new insights into the pathogenesis of LP-DLBCL and an explanation for the relatively low tumor cell content. Moreover, the findings suggest that treatment of these patients with immune checkpoint inhibitors may enhance an already ongoing host response in these patients.
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Affiliation(s)
- Bianca Schuhmacher
- Dr. Senckenberg Institute of Pathology, Goethe University, Frankfurt am Main, Germany
| | - Benjamin Rengstl
- Dr. Senckenberg Institute of Pathology, Goethe University, Frankfurt am Main, Germany
| | - Claudia Döring
- Dr. Senckenberg Institute of Pathology, Goethe University, Frankfurt am Main, Germany
| | - Julia Bein
- Dr. Senckenberg Institute of Pathology, Goethe University, Frankfurt am Main, Germany
| | - Sebastian Newrzela
- Dr. Senckenberg Institute of Pathology, Goethe University, Frankfurt am Main, Germany
| | - Uta Brunnberg
- Department of Internal Medicine 2, Hospital of the J. W. Goethe University, Frankfurt am Main, Germany
| | | | - Martine Vornanen
- Department of Pathology, Tampere University Hospital and University of Tampere, Tampere, Finland
| | - Ralf Küppers
- Institute of Cell Biology (Cancer Research), Faculty of Medicine, University of Duisburg-Essen, Essen, Germany
| | - Martin-Leo Hansmann
- Dr. Senckenberg Institute of Pathology, Goethe University, Frankfurt am Main, Germany
| | - Sylvia Hartmann
- Dr. Senckenberg Institute of Pathology, Goethe University, Frankfurt am Main, Germany
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27
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Bustos MA, Lucchesi O, Ruete MC, Tomes CN. Membrane-permeable Rab27A is a regulator of the acrosome reaction: Role of geranylgeranylation and guanine nucleotides. Cell Signal 2018; 44:72-81. [PMID: 29337043 DOI: 10.1016/j.cellsig.2018.01.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2017] [Revised: 12/18/2017] [Accepted: 01/09/2018] [Indexed: 12/11/2022]
Abstract
The acrosome reaction is the regulated exocytosis of mammalian sperm's single secretory granule, essential for fertilization. It relies on small GTPases, the cAMP binding protein Epac, and the SNARE complex, among other components. Here, we describe a novel tool to investigate Rab27-related signaling pathways: a hybrid recombinant protein consisting of human Rab27A fused to TAT, a cell penetrating peptide. With this tool, we aimed to unravel the connection between Rab3, Rab27 and Rap1 in sperm exocytosis and to deepen our understanding about how isoprenylation and guanine nucleotides influence the behaviour of Rab27 in exocytosis. Our results show that TAT-Rab27A-GTP-γ-S permeated into live sperm and triggered acrosomal exocytosis per se when geraylgeranylated but inhibited it when not lipid-modified. Likewise, an impermeant version of Rab27A elicited exocytosis in streptolysin O-permeabilized - but not in non-permeabilized - cells when geranylgeranylated and active. When GDP-β-S substituted for GTP-γ-S, isoprenylated TAT-Rab27A inhibited the acrosome reaction triggered by progesterone and an Epac-selective cAMP analogue, whereas the non-isoprenylated protein did not. Geranylgeranylated TAT-Rab27A-GTP-γ-S promoted the exchange of GDP for GTP on Rab3 and Rap1 detected by far-immunofluorescence with Rab3-GTP and Rap1-GTP binding cassettes. In contrast, TAT-Rab27A lacking isoprenylation or loaded with GDP-β-S prevented the activation of Rab3 and Rap1 elicited by progesterone. Challenging streptolysin O-permeabilized human sperm with calcium increased the population of sperm with Rap1-GTP, Rab3-GTP and Rab27-GTP in the acrosomal region; pretreatment with anti-Rab27 antibodies prevented the activation of all three. The novel findings reported here include: the description of membrane permeant TAT-Rab27A as a trustworthy tool to unveil the regulation of the human sperm acrosome reaction by Rab27 under physiological conditions; that the activation of endogenous Rab27 is required for that of Rab3 and Rap1; and the connection between Epac and Rab27 and between Rab27 and the configuration of the SNARE complex. Moreover, we present direct evidence that Rab27A's lipid modification, and activation/inactivation status correlate with its stimulatory or inhibitory roles in exocytosis.
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Affiliation(s)
- Matías A Bustos
- Instituto de Histologia y Embriologia de Mendoza (IHEM) Dr. Mario H. Burgos-CONICET, Universidad Nacional de Cuyo, casilla de correo 56, 5500 Mendoza, Argentina
| | - Ornella Lucchesi
- Instituto de Histologia y Embriologia de Mendoza (IHEM) Dr. Mario H. Burgos-CONICET, Universidad Nacional de Cuyo, casilla de correo 56, 5500 Mendoza, Argentina
| | - María C Ruete
- Instituto de Histologia y Embriologia de Mendoza (IHEM) Dr. Mario H. Burgos-CONICET, Universidad Nacional de Cuyo, casilla de correo 56, 5500 Mendoza, Argentina
| | - Claudia N Tomes
- Instituto de Histologia y Embriologia de Mendoza (IHEM) Dr. Mario H. Burgos-CONICET, Universidad Nacional de Cuyo, casilla de correo 56, 5500 Mendoza, Argentina.
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28
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Boland BB, Rhodes CJ, Grimsby JS. The dynamic plasticity of insulin production in β-cells. Mol Metab 2017; 6:958-973. [PMID: 28951821 PMCID: PMC5605729 DOI: 10.1016/j.molmet.2017.04.010] [Citation(s) in RCA: 117] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2017] [Revised: 04/27/2017] [Accepted: 04/28/2017] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND Although the insulin-producing pancreatic β-cells are quite capable of adapting to both acute and chronic changes in metabolic demand, persistently high demand for insulin will ultimately lead to their progressive dysfunction and eventual loss. Recent and historical studies highlight the importance of 'resting' the β-cell as a means of preserving functional β-cell mass. SCOPE OF REVIEW We provide experimental evidence to highlight the remarkable plasticity for insulin production and secretion by the pancreatic β-cell alongside some clinical evidence that supports leveraging this unique ability to preserve β-cell function. MAJOR CONCLUSIONS Treatment strategies for type 2 diabetes mellitus (T2DM) targeted towards reducing the systemic metabolic burden, rather than demanding greater insulin production from an already beleaguered β-cell, should be emphasized to maintain endogenous insulin secretory function and delay the progression of T2DM.
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Key Words
- ATF6, Activating Transcription Factor 6
- CHOP, CCAAT/Enhancer-Binding Homologous Protein
- EPAC, Exchange Factor Directly Activated by cAMP
- EROβ1, ER-resident oxidoreductase β1
- GIP, Gastric Inhibitory Polypeptide
- GLP-1, Glucagon-like Peptide 1
- GLUT2, Glucose Transporter 2
- GSIS, Glucose Stimulated Insulin Secretion
- IREα, Inositol Requiring Enzyme α
- Insulin production
- NEFA, Non-esterified Fatty Acid
- PERK, Protein Kinase RNA-like Endoplasmic Reticulum Kinase
- PKA, Protein Kinase A
- PKC, Protein Kinase C
- PLC, Phospholipase C
- ROS, Reactive Oxygen Species
- SNAP-25, Soluble NSF Attachment Protein 25
- SNARE, Soluble NSF Attachment Protein Receptor
- STZ, Streptozotocin
- T2DM
- T2DM, Type 2 Diabetes Mellitus
- TRP, Transient Receptor Potential
- VAMP-2, Vehicle Associated Membrane Protein 2
- VDCC, Voltage Dependent Calcium Channel
- mTORC1, Mammalian Target of Rapamycin 1
- nH, Hill coefficient
- β-cell rest
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Affiliation(s)
- Brandon B. Boland
- MedImmune, Cardiovascular and Metabolic Disease Research, 1 MedImmune Way, Gaithersburg, MD 20878, USA
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29
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Kubo Y, Masumoto H, Izumida M, Kakoki K, Hayashi H, Matsuyama T. Rab3a-Bound CD63 Is Degraded and Rab3a-Free CD63 Is Incorporated into HIV-1 Particles. Front Microbiol 2017; 8:1653. [PMID: 28900422 PMCID: PMC5581869 DOI: 10.3389/fmicb.2017.01653] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Accepted: 08/15/2017] [Indexed: 01/23/2023] Open
Abstract
CD63, a member of the tetraspanin family, is involved in virion production by human immunodeficiency virus type 1 (HIV-1), but its mechanism is unknown. In this study, we showed that a small GTP-binding protein, Rab3a, interacts with CD63. When Rab3a was exogenously expressed, the amounts of CD63 decreased in cells. The Rab3a-mediated reduction of CD63 was suppressed by lysosomal and proteasomal inhibitors. The amount of CD63 was increased by reducing the endogenous Rab3a level using a specific shRNA. These results indicate that Rab3a binds to CD63 to induce the degradation of CD63. Rab3a is thought to be involved in exocytosis, but we found that another function of Rab3a affects the fate of CD63 in lysosomes. CD63 interacted with Rab3a and was incorporated into HIV-1 particles. However, Rab3a was not detected in HIV-1 virions, thereby indicating that Rab3a-free CD63, but not Rab3a-bound CD63, is incorporated into HIV-1 particles. Overexpression or silencing of Rab3a moderately reduced HIV-1 virion formation. Overexpression of Rab3a decreased CD63 levels, but did not affect the incorporation of CD63 into HIV-1 particles. This study showed that Rab3a binds to CD63 to induce the degradation of CD63, and only Rab3a-free CD63 is incorporated into HIV-1 particles.
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Affiliation(s)
- Yoshinao Kubo
- Department of Molecular Microbiology and Immunology, Graduate School of Biomedical Sciences, Nagasaki UniversityNagasaki, Japan.,Program for Nurturing Global Leaders in Tropical and Emerging Communicable Diseases, Graduate School of Biomedical Sciences, Nagasaki UniversityNagasaki, Japan
| | - Hiroshi Masumoto
- Biomedical Research Support Center, Nagasaki University School of MedicineNagasaki, Japan
| | - Mai Izumida
- Department of Molecular Microbiology and Immunology, Graduate School of Biomedical Sciences, Nagasaki UniversityNagasaki, Japan.,Department of Clinical Medicine, Institute of Tropical Medicine, Nagasaki UniversityNagasaki, Japan
| | - Katsura Kakoki
- Department of Urology, Graduate School of Biomedical Sciences, Nagasaki UniversityNagasaki, Japan
| | - Hideki Hayashi
- Department of Molecular Microbiology and Immunology, Graduate School of Biomedical Sciences, Nagasaki UniversityNagasaki, Japan.,Medical University Research Administrator, Nagasaki University School of MedicineNagasaki, Japan
| | - Toshifumi Matsuyama
- Department of Molecular Microbiology and Immunology, Graduate School of Biomedical Sciences, Nagasaki UniversityNagasaki, Japan
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30
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Alonso B, Bartolomé-Martín D, Ferrero JJ, Ramírez-Franco J, Torres M, Sánchez-Prieto J. CB1 receptors down-regulate a cAMP/Epac2/PLC pathway to silence the nerve terminals of cerebellar granule cells. J Neurochem 2017; 142:350-364. [PMID: 28445587 DOI: 10.1111/jnc.14059] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2017] [Revised: 04/19/2017] [Accepted: 04/19/2017] [Indexed: 01/06/2023]
Abstract
Cannabinoid receptors mediate short-term retrograde inhibition of neurotransmitter release, as well as long-term depression of synaptic transmission at excitatory synapses. The responses of individual nerve terminals in VGLUT1-pHluorin transfected cerebellar granule cells to cannabinoids have shown that prolonged activation of cannabinoid type 1 receptors (CB1Rs) silences a subpopulation of previously active synaptic boutons. Adopting a combined pharmacological and genetic approach to study the molecular mechanisms of CB1R-induced silencing, we found that adenylyl cyclase inhibition decreases cAMP levels while it increases the number of silent synaptic boutons and occludes the induction of further silencing by the cannabinoid agonist HU-210. Guanine nucleotide exchange proteins directly activated by cAMP (Epac proteins) mediate some of the presynaptic effects of cAMP in the potentiation of synaptic transmission. ESI05, a selective Epac2 inhibitor, and U-73122, the specific inhibitor of phospholipase C (PLC), both augment the number of silent synaptic boutons. Moreover, they abolish the capacity of the Epac activator, 8-(4-chlorophenylthio)-2'-O-methyladenosine 3',5'-cyclic monophosphate monosodium hydrate, to prevent HU-210-induced silencing consistent with PLC signaling lying downstream of Epac2 proteins. Furthermore, Rab3-interacting molecule (RIM)1α KO cells have many more basally silent synaptic boutons (12.9 ± 3.5%) than wild-type cells (1.1 ± 0.5%). HU-210 induced further silencing in these mutant cells, although 8-(4-chlorophenylthio)-2'-O-methyladenosine 3',5'-cyclic monophosphate monosodium hydrate only awoke the HU-210-induced silence and not the basally silent synaptic boutons. This behavior can be rescued by expressing RIM1α in RIM1α KO cells, these cells behaving very much like wild-type cells. These findings support the hypothesis that a cAMP/Epac/PLC signaling pathway targeting the release machinery appears to mediate cannabinoid-induced presynaptic silencing.
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Affiliation(s)
- Beatris Alonso
- Departamento de Bioquímica, Facultad de Veterinaria, Universidad Complutense, Madrid, Spain.,Instituto de Investigación Sanitaria del Hospital Clínico San Carlos, Madrid, Spain
| | - David Bartolomé-Martín
- Departamento de Bioquímica, Facultad de Veterinaria, Universidad Complutense, Madrid, Spain.,Instituto de Investigación Sanitaria del Hospital Clínico San Carlos, Madrid, Spain
| | - José Javier Ferrero
- Departamento de Bioquímica, Facultad de Veterinaria, Universidad Complutense, Madrid, Spain.,Instituto de Investigación Sanitaria del Hospital Clínico San Carlos, Madrid, Spain
| | - Jorge Ramírez-Franco
- Departamento de Bioquímica, Facultad de Veterinaria, Universidad Complutense, Madrid, Spain.,Instituto de Investigación Sanitaria del Hospital Clínico San Carlos, Madrid, Spain
| | - Magdalena Torres
- Departamento de Bioquímica, Facultad de Veterinaria, Universidad Complutense, Madrid, Spain.,Instituto de Investigación Sanitaria del Hospital Clínico San Carlos, Madrid, Spain
| | - José Sánchez-Prieto
- Departamento de Bioquímica, Facultad de Veterinaria, Universidad Complutense, Madrid, Spain.,Instituto de Investigación Sanitaria del Hospital Clínico San Carlos, Madrid, Spain
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31
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Host Epac1 is required for cAMP-mediated invasion by Trypanosoma cruzi. Mol Biochem Parasitol 2016; 211:67-70. [PMID: 27984073 DOI: 10.1016/j.molbiopara.2016.10.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2016] [Revised: 10/25/2016] [Accepted: 10/26/2016] [Indexed: 02/03/2023]
Abstract
Mechanistic details of the modulation by cAMP of Trypanosoma cruzi host cell invasion remain ill-defined. Here we report that activation of host's Epac1 stimulated invasion, whereas specific pharmacological inhibition or maneuvers that alter Epac1 subcellular localization significantly reduced invasion. Furthermore, while specific activation of host cell PKA showed no effect, its inhibition resulted in an increased invasion, revealing a crosstalk between the PKA and Epac signaling pathways during the process of invasion. Therefore, our data suggests that subcellular localization of Epac might be playing an important role during invasion and that specific activation of the host cell cAMP/Epac1 pathway is required for cAMP-mediated invasion.
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32
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Quevedo MF, Lucchesi O, Bustos MA, Pocognoni CA, De la Iglesia PX, Tomes CN. The Rab3A-22A Chimera Prevents Sperm Exocytosis by Stabilizing Open Fusion Pores. J Biol Chem 2016; 291:23101-23111. [PMID: 27613869 DOI: 10.1074/jbc.m116.729954] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Indexed: 11/06/2022] Open
Abstract
At the final stage of exocytotis, a fusion pore opens between the plasma and a secretory vesicle membranes; typically, when the pore dilates the vesicle releases its cargo. Sperm contain a large dense-core secretory granule (the acrosome) whose contents are secreted by regulated exocytosis at fertilization. Minutes after the arrival of the triggering signal, the acrosomal and plasma membranes dock at multiple sites and fusion pores open at the contact points. It is believed that immediately afterward, fusion pores dilate spontaneously. Rab3A is an essential component of human sperm exocytotic machinery. Yet, recombinant, persistently active Rab3A halts calcium-triggered secretion when introduced after docking into streptolysin O-permeabilized cells; so does a Rab3A-22A chimera. Here, we applied functional assays, electron and confocal microscopy to show that the secretion blockage is due to the stabilization of open fusion pores. Other novel findings are that sperm SNAREs engage in α-SNAP/NSF-sensitive complexes at a post-fusion stage. Complexes are disentangled by these chaperons to achieve vesiculation and acrosomal contents release. Thus, post-fusion regulation of the pores determines their expansion and the success of the acrosome reaction.
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Affiliation(s)
- María F Quevedo
- From the IHEM, Universidad Nacional de Cuyo, CONICET, Facultad de Ciencias Médicas, CC56. 5500 Mendoza, Argentina
| | - Ornella Lucchesi
- From the IHEM, Universidad Nacional de Cuyo, CONICET, Facultad de Ciencias Médicas, CC56. 5500 Mendoza, Argentina
| | - Matías A Bustos
- From the IHEM, Universidad Nacional de Cuyo, CONICET, Facultad de Ciencias Médicas, CC56. 5500 Mendoza, Argentina
| | - Cristian A Pocognoni
- From the IHEM, Universidad Nacional de Cuyo, CONICET, Facultad de Ciencias Médicas, CC56. 5500 Mendoza, Argentina
| | - Paola X De la Iglesia
- From the IHEM, Universidad Nacional de Cuyo, CONICET, Facultad de Ciencias Médicas, CC56. 5500 Mendoza, Argentina
| | - Claudia N Tomes
- From the IHEM, Universidad Nacional de Cuyo, CONICET, Facultad de Ciencias Médicas, CC56. 5500 Mendoza, Argentina
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33
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Goupil S, Maréchal L, El Hajj H, Tremblay MÈ, Richard FJ, Leclerc P. Identification and Localization of the Cyclic Nucleotide Phosphodiesterase 10A in Bovine Testis and Mature Spermatozoa. PLoS One 2016; 11:e0161035. [PMID: 27548062 PMCID: PMC4993467 DOI: 10.1371/journal.pone.0161035] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2016] [Accepted: 07/28/2016] [Indexed: 11/19/2022] Open
Abstract
In mammals, adenosine 3’, 5’-cyclic monophosphate (cAMP) is known to play highly important roles in sperm motility and acrosomal exocytosis. It is known to act through protein phosphorylation via PRKA and through the activation of guanine nucleotide exchange factors like EPAC. Sperm intracellular cAMP levels depend on the activity of adenylyl cyclases, mostly SACY, though transmembrane-containing adenylyl cyclases are also present, and on the activity of cyclic nucleotide phosphodiesterases (PDE) whose role is to degrade cAMP into 5’-AMP. The PDE superfamily is subdivided into 11 families (PDE1 to 11), which act on either cAMP or cGMP, or on both cAMP and cGMP although with different enzymatic properties. PDE10, which is more effective on cAMP than cGMP, has been known for almost 15 years and is mostly studied in the brain where it is associated with neurological disorders. Although a high level of PDE10A gene expression is observed in the testis, information on the identity of the isoforms or on the cell type that express the PDE10 protein is lacking. The objective of this study was to identify the PDE10A isoforms expressed in the testis and germ cells, and to determine the presence and localization of PDE10A in mature spermatozoa. As a sub-objective, since PDE10A transcript variants were reported strictly through analyses of bovine genomic sequence, we also wanted to determine the nucleotide and amino acid sequences by experimental evidence. Using RT-PCR, 5’- and 3’-RACE approaches we clearly show that PDE10A transcript variants X3 and X5 are expressed in bovine testis as well as in primary spermatocytes and spermatids. We also reveal using a combination of immunological techniques and proteomics analytical tools that the PDE10A isoform X4 is present in the area of the developing acrosome of spermatids and of the acrosome of mature spermatozoa.
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Affiliation(s)
- Serge Goupil
- Département d’obstétrique, gynécologie et reproduction, Université Laval, et Centre de recherche du CHU de Québec-Université Laval, Québec, Canada
- Centre de recherche en reproduction, développement et santé intergénérationnelle (CRDSI), Université Laval, Québec, Canada
- Centre de recherche du CHU de Québec-Université Laval, G1V 4G2, Québec, QC, Canada
| | - Loïze Maréchal
- Département d’obstétrique, gynécologie et reproduction, Université Laval, et Centre de recherche du CHU de Québec-Université Laval, Québec, Canada
- Centre de recherche en reproduction, développement et santé intergénérationnelle (CRDSI), Université Laval, Québec, Canada
- Centre de recherche du CHU de Québec-Université Laval, G1V 4G2, Québec, QC, Canada
| | - Hassan El Hajj
- Département de médecine moléculaire, Université Laval, et Centre de recherche du CHU de Québec-Université Laval, Québec, Canada
- Centre de recherche du CHU de Québec-Université Laval, G1V 4G2, Québec, QC, Canada
| | - Marie-Ève Tremblay
- Département de médecine moléculaire, Université Laval, et Centre de recherche du CHU de Québec-Université Laval, Québec, Canada
- Centre de recherche du CHU de Québec-Université Laval, G1V 4G2, Québec, QC, Canada
| | - François J. Richard
- Département des sciences animales, Université Laval, et Centre de recherche du CHU de Québec-Université Laval, Québec, Canada
- Centre de recherche en reproduction, développement et santé intergénérationnelle (CRDSI), Université Laval, Québec, Canada
| | - Pierre Leclerc
- Département d’obstétrique, gynécologie et reproduction, Université Laval, et Centre de recherche du CHU de Québec-Université Laval, Québec, Canada
- Centre de recherche en reproduction, développement et santé intergénérationnelle (CRDSI), Université Laval, Québec, Canada
- Centre de recherche du CHU de Québec-Université Laval, G1V 4G2, Québec, QC, Canada
- * E-mail:
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Belmonte SA, Mayorga LS, Tomes CN. The Molecules of Sperm Exocytosis. ADVANCES IN ANATOMY EMBRYOLOGY AND CELL BIOLOGY 2016; 220:71-92. [PMID: 27194350 DOI: 10.1007/978-3-319-30567-7_4] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Exocytosis is a fundamental process used by eukaryotic cells to release biological compounds and to insert lipids and proteins in the plasma membrane. Specialized secretory cells undergo regulated exocytosis in response to physiological signals. Sperm exocytosis or acrosome reaction (AR) is essentially a regulated secretion with special characteristics. We will focus here on some of these unique features, covering the topology, kinetics, and molecular mechanisms that prepare, drive, and regulate membrane fusion during the AR. Last, we will compare acrosomal release with exocytosis in other model systems.
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Affiliation(s)
- Silvia A Belmonte
- Laboratorio de Biología Celular y Molecular, Instituto de Histología y Embriología, IHEM-CONICET, Facultad de Ciencias Médicas, Universidad Nacional de Cuyo, 5500, Mendoza, Mendoza, Argentina
| | - Luis S Mayorga
- Laboratorio de Biología Celular y Molecular, Instituto de Histología y Embriología, IHEM-CONICET, Facultad de Ciencias Médicas, Universidad Nacional de Cuyo, 5500, Mendoza, Mendoza, Argentina
| | - Claudia N Tomes
- Laboratorio de Biología Celular y Molecular, Instituto de Histología y Embriología, IHEM-CONICET, Facultad de Ciencias Médicas, Universidad Nacional de Cuyo, 5500, Mendoza, Mendoza, Argentina.
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Bustos MA, Lucchesi O, Ruete MC, Mayorga LS, Tomes CN. Small GTPases in acrosomal exocytosis. Methods Mol Biol 2016; 1298:141-60. [PMID: 25800839 DOI: 10.1007/978-1-4939-2569-8_12] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Regulated exocytosis employs a conserved molecular machinery in all secretory cells. Soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) and Rab superfamilies are members of this machinery. Rab proteins are small GTPases that organize membrane microdomains on organelles by recruiting specific effectors that strongly influence the movement, fusion and fission dynamics of intracellular compartments. Rab3 and Rab27 are the prevalent exocytotic isoforms. Many events occur in mammalian spermatozoa before they can fertilize the egg, one of them is the acrosome reaction (AR), a type of regulated exocytosis. The AR relies on the same fusion machinery as all other cell types, which includes members of the exocytotic SNARE and Rab superfamilies. Here, we describe in depth two protocols designed to determine the activation status of small G proteins. One of them also serves to determine the subcellular localization of active Rabs, something not achievable with other methods. By means of these techniques, we have reported that Rab27 and Rab3 act sequentially and are organized in a RabGEF cascade during the AR. Although we developed them to scrutinize the exocytosis of the acrosome in human sperm, the protocols can potentially be extended to study other Ras-related proteins in virtually any cellular model.
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Affiliation(s)
- Matias A Bustos
- Instituto de Histología y Embriología (IHEM, CONICET/UNCuyo), Facultad de Ciencias Médicas, CC56, Universidad Nacional de Cuyo, 5500, Mendoza, Argentina
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Sosa CM, Zanetti MN, Pocognoni CA, Mayorga LS. Acrosomal Swelling Is Triggered by cAMP Downstream of the Opening of Store-Operated Calcium Channels During Acrosomal Exocytosis in Human Sperm. Biol Reprod 2016; 94:57. [PMID: 26792943 DOI: 10.1095/biolreprod.115.133231] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2015] [Accepted: 01/15/2016] [Indexed: 11/01/2022] Open
Abstract
Acrosomal exocytosis in mammalian sperm is a regulated secretion with unusual characteristics. One of its most striking features is the postfusion loss of the outer acrosomal membrane and the overlying plasma membrane as hybrid vesicles. We have previously reported in human sperm that, by preventing the release of calcium from the acrosome, the exocytic process can be arrested at a stage where the acrosomes are profusely swollen, with invaginations of the outer acrosomal membrane. In this report, we show by transmission electron microcopy swelling with similar characteristics without arresting the exocytic process. Acrosomal swelling was observed when secretion was promoted by pharmacological and physiological inducers of the acrosome reaction that trigger exocytosis by different mechanisms. We show that progesterone- and thapsigargin-induced swelling depended on a calcium influx from the extracellular medium through store-operated calcium channels. However, calcium was dispensable when sperm were stimulated with cAMP analogs. KH7, an inhibitor of the soluble adenylyl cyclase, blocked progesterone-induced swelling. Our results indicate that swelling is a required process for acrosomal exocytosis triggered by activation of an adenylyl cyclase downstream of the opening of store-operated calcium channels.
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Affiliation(s)
- Claudia M Sosa
- Instituto de Histología y Embriología de Mendoza (IHEM/CONICET-UNCuyo), School of Medicine, National University of Cuyo, Mendoza, Argentina
| | - M Natalia Zanetti
- Instituto de Histología y Embriología de Mendoza (IHEM/CONICET-UNCuyo), School of Medicine, National University of Cuyo, Mendoza, Argentina
| | - Cristian A Pocognoni
- Instituto de Histología y Embriología de Mendoza (IHEM/CONICET-UNCuyo), School of Medicine, National University of Cuyo, Mendoza, Argentina
| | - Luis S Mayorga
- Instituto de Histología y Embriología de Mendoza (IHEM/CONICET-UNCuyo), School of Medicine, National University of Cuyo, Mendoza, Argentina
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Lucchesi O, Ruete MC, Bustos MA, Quevedo MF, Tomes CN. The signaling module cAMP/Epac/Rap1/PLCε/IP3 mobilizes acrosomal calcium during sperm exocytosis. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2015; 1863:544-61. [PMID: 26704387 DOI: 10.1016/j.bbamcr.2015.12.007] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 08/01/2015] [Revised: 11/23/2015] [Accepted: 12/14/2015] [Indexed: 12/29/2022]
Abstract
Exocytosis of the sperm's single secretory granule, or acrosome, is a regulated exocytosis triggered by components of the egg's investments. In addition to external calcium, sperm exocytosis (termed the acrosome reaction) requires cAMP synthesized endogenously and calcium mobilized from the acrosome through IP3-sensitive channels. The relevant cAMP target is Epac. In the first part of this paper, we present a novel tool (the TAT-cAMP sponge) to investigate cAMP-related signaling pathways in response to progesterone as acrosome reaction trigger. The TAT-cAMP sponge consists of the cAMP-binding sites of protein kinase A regulatory subunit RIβ fused to the protein transduction domain TAT of the human immunodeficiency virus-1. The sponge permeated into sperm, sequestered endogenous cAMP, and blocked exocytosis. Progesterone increased the population of sperm with Rap1-GTP, Rab3-GTP, and Rab27-GTP in the acrosomal region; pretreatment with the TAT-cAMP sponge prevented the activation of all three GTPases. In the second part of this manuscript, we show that phospholipase Cε (PLCε) is required for the acrosome reaction downstream of Rap1 and upstream of intra-acrosomal calcium mobilization. Last, we present direct evidence that cAMP, Epac, Rap1, and PLCε are necessary for calcium mobilization from sperm's secretory granule. In summary, we describe here a pathway that connects cAMP to calcium mobilization from the acrosome during sperm exocytosis. Never before had direct evidence for each step of the cascade been put together in the same study.
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Affiliation(s)
- Ornella Lucchesi
- Laboratorio de Biología Celular y Molecular, Instituto de Histología y Embriología, IHEM-CONICET, Facultad de Ciencias Médicas, Universidad Nacional de Cuyo, Mendoza 5500, Argentina
| | - María C Ruete
- Laboratorio de Biología Celular y Molecular, Instituto de Histología y Embriología, IHEM-CONICET, Facultad de Ciencias Médicas, Universidad Nacional de Cuyo, Mendoza 5500, Argentina
| | - Matías A Bustos
- Laboratorio de Biología Celular y Molecular, Instituto de Histología y Embriología, IHEM-CONICET, Facultad de Ciencias Médicas, Universidad Nacional de Cuyo, Mendoza 5500, Argentina
| | - María F Quevedo
- Laboratorio de Biología Celular y Molecular, Instituto de Histología y Embriología, IHEM-CONICET, Facultad de Ciencias Médicas, Universidad Nacional de Cuyo, Mendoza 5500, Argentina
| | - Claudia N Tomes
- Laboratorio de Biología Celular y Molecular, Instituto de Histología y Embriología, IHEM-CONICET, Facultad de Ciencias Médicas, Universidad Nacional de Cuyo, Mendoza 5500, Argentina.
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Isono A, Tate S, Nakamura-Mori K, Noda T, Ishikawa S, Harayama H. Involvement of cAMP-dependent unique signaling cascades in the decrease of serine/threonine-phosphorylated proteins in boar sperm head. Theriogenology 2015; 85:1152-60. [PMID: 26747578 DOI: 10.1016/j.theriogenology.2015.11.031] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2015] [Revised: 10/20/2015] [Accepted: 11/28/2015] [Indexed: 12/12/2022]
Abstract
We previously suggested that protein phosphatase-dependent decrease of postacrosomal phosphorylated proteins may be necessary for the occurrence of acrosome reaction in livestock spermatozoa (Adachi et al., J Reprod Dev 54, 171-176, 2008; Mizuno et al., Mol Reprod Dev 82, 232-250, 2015). The aim of this study was to examine the involvement of the intracellular cAMP signaling cascades in the regulation of the decrease of postacrosomal phosphorylated proteins in boar spermatozoa. Boar ejaculated spermatozoa were incubated with cAMP analogs and then used for the immunodetection of serine/threonine-phosphorylated proteins and assessment of acrosome morphology. The protein phosphatase-dependent decrease of postacrosomal phosphorylated proteins was greatly promoted by the incubation with a cAMP analog Sp-5,6-dichloro-1-β-D-ribofuranosyl-benzimidazole-3',5'-monophosphorothioate (cBiMPS). This decrease was induced before the initiation of acrosome reaction and did not require the millimolar concentration of extracellular Ca(2+) which was necessary for the initiation of acrosome reaction. Moreover, suppression of protein kinase A activity with an inhibitor (H89) had almost no influence on both decrease of phosphorylated proteins and occurrence of acrosome reaction in the spermatozoa incubated with cBiMPS. In addition, the prolonged incubation with a potentially exchange protein directly activated by cAMP-selective cAMP analog (8pM) could only partially mimic effects of cBiMPS on these events. These results indicate that the cAMP-dependent signaling cascades which are less dependent on protein kinase A may regulate the decrease of postacrosomal phosphorylated proteins in boar spermatozoa before the extracellular Ca(2+)-triggered initiation of acrosome reaction.
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Affiliation(s)
- Ayane Isono
- Laboratory of Reproductive Biology, Division of Animal Science, Department of Bioresource Science, Graduate School of Agricultural Science, Kobe University, Kobe, Hyogo, Japan
| | - Shunsuke Tate
- Laboratory of Reproductive Biology, Division of Animal Science, Department of Bioresource Science, Graduate School of Agricultural Science, Kobe University, Kobe, Hyogo, Japan
| | - Kazumi Nakamura-Mori
- Laboratory of Reproductive Biology, Division of Animal Science, Department of Bioresource Science, Graduate School of Agricultural Science, Kobe University, Kobe, Hyogo, Japan
| | - Taichi Noda
- Laboratory of Reproductive Biology, Division of Animal Science, Department of Bioresource Science, Graduate School of Agricultural Science, Kobe University, Kobe, Hyogo, Japan
| | - Sho Ishikawa
- General Technological Center of Hyogo Prefecture for Agriculture, Forest and Fishery, Awaji, Hyogo, Japan
| | - Hiroshi Harayama
- Laboratory of Reproductive Biology, Division of Animal Science, Department of Bioresource Science, Graduate School of Agricultural Science, Kobe University, Kobe, Hyogo, Japan.
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Lackey BR, Gray SL. Second messengers, steroids and signaling cascades: Crosstalk in sperm development and function. Gen Comp Endocrinol 2015; 224:294-302. [PMID: 26188217 DOI: 10.1016/j.ygcen.2015.07.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/18/2015] [Revised: 07/08/2015] [Accepted: 07/14/2015] [Indexed: 10/23/2022]
Abstract
Signaling cascades control numerous aspects of sperm physiology, ranging from creation to fertilization. Novel aspects of several kinases and their influence on sperm development will be discussed in the first section and cover proliferation, chromatin remodeling and morphology. In the second section, protein kinases (A, B and C) that affect sperm function and their regulation by second messengers, cyclic-AMP and phosphoinositides, as well as steroids will be featured. Key areas of integration will be presented on the topics of sperm motility, capacitation, acrosome reaction and fertilization.
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Affiliation(s)
- B R Lackey
- Endocrine Physiology Laboratory, AVS Department, Clemson University, Clemson, SC, USA
| | - S L Gray
- Endocrine Physiology Laboratory, AVS Department, Clemson University, Clemson, SC, USA.
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Thompson MA, Britt RD, Kuipers I, Stewart A, Thu J, Pandya HC, MacFarlane P, Pabelick CM, Martin RJ, Prakash YS. cAMP-mediated secretion of brain-derived neurotrophic factor in developing airway smooth muscle. BIOCHIMICA ET BIOPHYSICA ACTA 2015; 1853:2506-14. [PMID: 26112987 PMCID: PMC4558218 DOI: 10.1016/j.bbamcr.2015.06.008] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2015] [Revised: 05/28/2015] [Accepted: 06/20/2015] [Indexed: 01/12/2023]
Abstract
Moderate hyperoxic exposure in preterm infants contributes to subsequent airway dysfunction and to risk of developing recurrent wheeze and asthma. The regulatory mechanisms that can contribute to hyperoxia-induced airway dysfunction are still under investigation. Recent studies in mice show that hyperoxia increases brain-derived neurotrophic factor (BDNF), a growth factor that increases airway smooth muscle (ASM) proliferation and contractility. We assessed the mechanisms underlying effects of moderate hyperoxia (50% O2) on BDNF expression and secretion in developing human ASM. Hyperoxia increased BDNF secretion, but did not alter endogenous BDNF mRNA or intracellular protein levels. Exposure to hyperoxia significantly increased [Ca2+]i responses to histamine, an effect blunted by the BDNF chelator TrkB-Fc. Hyperoxia also increased ASM cAMP levels, associated with reduced PDE4 activity, but did not alter protein kinase A (PKA) activity or adenylyl cyclase mRNA levels. However, 50% O2 increased expression of Epac2, which is activated by cAMP and can regulate protein secretion. Silencing RNA studies indicated that Epac2, but not Epac1, is important for hyperoxia-induced BDNF secretion, while PKA inhibition did not influence BDNF secretion. In turn, BDNF had autocrine effects of enhancing ASM cAMP levels, an effect inhibited by TrkB and BDNF siRNAs. Together, these novel studies suggest that hyperoxia can modulate BDNF secretion, via cAMP-mediated Epac2 activation in ASM, resulting in a positive feedback effect of BDNF-mediated elevation in cAMP levels. The potential functional role of this pathway is to sustain BDNF secretion following hyperoxic stimulus, leading to enhanced ASM contractility and proliferation.
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Affiliation(s)
| | - Rodney D Britt
- Department of Anesthesiology Mayo Clinic, Rochester, MN, USA
| | - Ine Kuipers
- Department of Anesthesiology Mayo Clinic, Rochester, MN, USA
| | - Alecia Stewart
- Department of Anesthesiology Mayo Clinic, Rochester, MN, USA
| | - James Thu
- Department of Anesthesiology Mayo Clinic, Rochester, MN, USA
| | - Hitesh C Pandya
- Department Pediatrics, University of Leicester, Leicester, UK
| | - Peter MacFarlane
- Department of Pediatrics, Division of Neonatology, Rainbow Babies Children's Hospital, Case Western Reserve University, Cleveland, OH, USA
| | - Christina M Pabelick
- Department of Anesthesiology Mayo Clinic, Rochester, MN, USA; Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN, USA
| | - Richard J Martin
- Department of Pediatrics, Division of Neonatology, Rainbow Babies Children's Hospital, Case Western Reserve University, Cleveland, OH, USA
| | - Y S Prakash
- Department of Anesthesiology Mayo Clinic, Rochester, MN, USA; Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN, USA.
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Ferrero JJ, Ramírez-Franco J, Martín R, Bartolomé-Martín D, Torres M, Sánchez-Prieto J. Cross-talk between metabotropic glutamate receptor 7 and beta adrenergic receptor signaling at cerebrocortical nerve terminals. Neuropharmacology 2015. [PMID: 26211974 DOI: 10.1016/j.neuropharm.2015.07.025] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The co-existence of presynaptic G protein coupled receptors, GPCRs, has received little attention, despite the fact that interplay between the signaling pathways activated by such receptors may affect the neurotransmitter release. Using immunocytochemistry and immuhistochemistry we show that mGlu7 and β-adrenergic receptors are co-expressed in a sub-population of cerebrocortical nerve terminals. mGlu7 receptors readily couple to pathways that inhibit glutamate release. We found that when mGlu7 receptors are also coupled to pathways that enhance glutamate release by prolonged exposure to agonist, and β-adrenergic receptors are also activated, a cross-talk between their signaling pathways occurs that affect the overall release response. This interaction is the result of mGlu7 receptors inhibiting the adenylyl cyclase activated by β adrenergic receptors. Thus, blocking Gi/o proteins with pertussis toxin provokes a further increase in release after receptor co-activation which is also observed after activating β-adrenergic receptor signaling pathways downstream of adenylyl cyclase with the cAMP analog Sp8Br or 8pCPT-2-OMe-cAMP (a specific activator of the guanine nucleotide exchange protein directly activated by cAMP, EPAC). Co-activation of mGlu7 and β-adrenergic receptors also enhances PLC-dependent accumulation of IP1 and the translocation of the active zone protein Munc13-1 to the membrane, indicating that release potentiation by these receptors involves the modulation of the release machinery.
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Affiliation(s)
- José Javier Ferrero
- Departamento de Bioquímica, Facultad de Veterinaria, Universidad Complutense, 28040 Madrid, Spain; Instituto de Investigación Sanitaria del Hospital Clínico San Carlos, Hospital Clínico San Carlos, C/Profesor Martín Lagos s/n, Madrid 28040, Spain
| | - Jorge Ramírez-Franco
- Departamento de Bioquímica, Facultad de Veterinaria, Universidad Complutense, 28040 Madrid, Spain
| | - Ricardo Martín
- Departamento de Bioquímica, Facultad de Veterinaria, Universidad Complutense, 28040 Madrid, Spain; Instituto de Investigación Sanitaria del Hospital Clínico San Carlos, Hospital Clínico San Carlos, C/Profesor Martín Lagos s/n, Madrid 28040, Spain
| | - David Bartolomé-Martín
- Departamento de Bioquímica, Facultad de Veterinaria, Universidad Complutense, 28040 Madrid, Spain; Instituto de Investigación Sanitaria del Hospital Clínico San Carlos, Hospital Clínico San Carlos, C/Profesor Martín Lagos s/n, Madrid 28040, Spain
| | - Magdalena Torres
- Departamento de Bioquímica, Facultad de Veterinaria, Universidad Complutense, 28040 Madrid, Spain; Instituto de Investigación Sanitaria del Hospital Clínico San Carlos, Hospital Clínico San Carlos, C/Profesor Martín Lagos s/n, Madrid 28040, Spain
| | - José Sánchez-Prieto
- Departamento de Bioquímica, Facultad de Veterinaria, Universidad Complutense, 28040 Madrid, Spain; Instituto de Investigación Sanitaria del Hospital Clínico San Carlos, Hospital Clínico San Carlos, C/Profesor Martín Lagos s/n, Madrid 28040, Spain.
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Epac2 Mediates cAMP-Dependent Potentiation of Neurotransmission in the Hippocampus. J Neurosci 2015; 35:6544-53. [PMID: 25904804 DOI: 10.1523/jneurosci.0314-14.2015] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Presynaptic terminal cAMP elevation plays a central role in plasticity at the mossy fiber-CA3 synapse of the hippocampus. Prior studies have identified protein kinase A as a downstream effector of cAMP that contributes to mossy fiber LTP (MF-LTP), but the potential contribution of Epac2, another cAMP effector expressed in the MF synapse, has not been considered. We investigated the role of Epac2 in MF-CA3 neurotransmission using Epac2(-/-) mice. The deletion of Epac2 did not cause gross alterations in hippocampal neuroanatomy or basal synaptic transmission. Synaptic facilitation during short trains was not affected by loss of Epac2 activity; however, both long-term plasticity and forskolin-mediated potentiation of MFs were impaired, demonstrating that Epac2 contributes to cAMP-dependent potentiation of transmitter release. Examination of synaptic transmission during long sustained trains of activity suggested that the readily releasable pool of vesicles is reduced in Epac2(-/-) mice. These data suggest that cAMP elevation uses an Epac2-dependent pathway to promote transmitter release, and that Epac2 is required to maintain the readily releasable pool at MF synapses in the hippocampus.
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Abstract
Exocytosis is a highly regulated process that consists of multiple functionally, kinetically and/or morphologically definable stages such as recruitment, targeting, tethering and docking of secretory vesicles with the plasma membrane, priming of the fusion machinery and calcium-triggered membrane fusion. After fusion, the membrane around the secretory vesicle is incorporated into the plasma membrane and the granule releases its contents. The proteins involved in these processes belong to several highly conserved families: Rab GTPases, SNAREs (soluble NSF-attachment protein receptors), α-SNAP (α-NSF attachment protein), NSF (N-ethylmaleimide-sensitive factor), Munc13 and -18, complexins and synaptotagmins. In the present article, the molecules of exocytosis are reviewed, using human sperm as a model system. Sperm exocytosis is driven by isoforms of the same proteinaceous fusion machinery mentioned above, with their functions orchestrated in a hierarchically organized and unidirectional signalling cascade. In addition to the universal exocytosis regulator calcium, this cascade includes other second messengers such as diacylglycerol, inositol 1,4,5-trisphosphate and cAMP, as well as the enzymes that synthesize them and their target proteins. Of special interest is the cAMP-binding protein Epac (exchange protein directly activated by cAMP) due in part to its enzymatic activity towards Rap. The activation of Epac and Rap leads to a highly localized calcium signal which, together with assembly of the SNARE complex, governs the final stages of exocytosis. The source of this releasable calcium is the secretory granule itself.
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Bustos MA, Roggero CM, De la Iglesia PX, Mayorga LS, Tomes CN. GTP-bound Rab3A exhibits consecutive positive and negative roles during human sperm dense-core granule exocytosis. J Mol Cell Biol 2015; 6:286-98. [PMID: 25053757 DOI: 10.1093/jmcb/mju021] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Exocytosis of mammalian sperm dense-core secretory granule relies on the same fusion molecules as all other secretory cells; one such molecule is the small GTPase Rab3A. Here, we report an in-depth biochemical characterization of the role of Rab3A in secretion by scrutinizing the exocytotic response of streptolysin O-permeabilized human sperm to the acute application of a number of Rab3A-containing constructs and correlating the findings with those gathered with the endogenous protein. Full length, geranylgeranylated, and active Rab3A elicited human sperm exocytosis per se. With Rab3A/Rab22A chimeric proteins, we demonstrated that the carboxy-terminal domain of the Rab3A molecule was necessary and sufficient to promote exocytosis, whereas its amino-terminus prevented calcium-triggered secretion. Interestingly, full length Rab3A halted secretion when added after the docking of the acrosome to the plasma membrane. This effect depended on the inability of Rab3A to hydrolyze GTP. We combined modified immunofluorescence and acrosomal staining protocols to detect membrane fusion and the activation status of endogenous Rab3 simultaneously in individual cells, and found that GTP hydrolysis on endogenous Rab3 was mandatory for fusion pores to open. Our findings contribute to establishing that Rab3 modulates regulated exocytosis differently depending on the nucleotide bound and the exocytosis stage under study.
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Affiliation(s)
- Matías A Bustos
- Instituto de Histología y Embriología, IHEM-CONICET, Facultad de Ciencias Médicas, Universidad Nacional de Cuyo, Mendoza, Argentina
| | - Carlos M Roggero
- Instituto de Histología y Embriología, IHEM-CONICET, Facultad de Ciencias Médicas, Universidad Nacional de Cuyo, Mendoza, Argentina Present address: Department of Biophysics, UT Southwestern Medical Center, Dallas, TX, USA
| | - Paola X De la Iglesia
- Instituto de Histología y Embriología, IHEM-CONICET, Facultad de Ciencias Médicas, Universidad Nacional de Cuyo, Mendoza, Argentina Present address: Servicio de Patología, Hospital Italiano de Buenos Aires, Buenos Aires, Argentina
| | - Luis S Mayorga
- Instituto de Histología y Embriología, IHEM-CONICET, Facultad de Ciencias Médicas, Universidad Nacional de Cuyo, Mendoza, Argentina
| | - Claudia N Tomes
- Instituto de Histología y Embriología, IHEM-CONICET, Facultad de Ciencias Médicas, Universidad Nacional de Cuyo, Mendoza, Argentina
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Pelletán LE, Suhaiman L, Vaquer CC, Bustos MA, De Blas GA, Vitale N, Mayorga LS, Belmonte SA. ADP ribosylation factor 6 (ARF6) promotes acrosomal exocytosis by modulating lipid turnover and Rab3A activation. J Biol Chem 2015; 290:9823-41. [PMID: 25713146 DOI: 10.1074/jbc.m114.629006] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2014] [Indexed: 11/06/2022] Open
Abstract
Regulated secretion is a central issue for the specific function of many cells; for instance, mammalian sperm acrosomal exocytosis is essential for egg fertilization. ARF6 (ADP-ribosylation factor 6) is a small GTPase implicated in exocytosis, but its downstream effectors remain elusive in this process. We combined biochemical, functional, and microscopy-based methods to show that ARF6 is present in human sperm, localizes to the acrosomal region, and is required for calcium and diacylglycerol-induced exocytosis. Results from pulldown assays show that ARF6 exchanges GDP for GTP in sperm challenged with different exocytic stimuli. Myristoylated and guanosine 5'-3-O-(thio)triphosphate (GTPγS)-loaded ARF6 (active form) added to permeabilized sperm induces acrosome exocytosis even in the absence of extracellular calcium. We explore the ARF6 signaling cascade that promotes secretion. We demonstrate that ARF6 stimulates a sperm phospholipase D activity to produce phosphatidic acid and boosts the synthesis of phosphatidylinositol 4,5-bisphosphate. We present direct evidence showing that active ARF6 increases phospholipase C activity, causing phosphatidylinositol 4,5-bisphosphate hydrolysis and inositol 1,4,5-trisphosphate-dependent intra-acrosomal calcium release. We show that active ARF6 increases the exchange of GDP for GTP on Rab3A, a prerequisite for secretion. We propose that exocytic stimuli activate ARF6, which is required for acrosomal calcium efflux and the assembly of the membrane fusion machinery. This report highlights the physiological importance of ARF6 as a key factor for human sperm exocytosis and fertilization.
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Affiliation(s)
- Leonardo E Pelletán
- From the Instituto de Histología y Embriología, CONICET, Facultad de Ciencias Médicas, CC56, Universidad Nacional de Cuyo, 5500 Mendoza, Argentina and
| | - Laila Suhaiman
- From the Instituto de Histología y Embriología, CONICET, Facultad de Ciencias Médicas, CC56, Universidad Nacional de Cuyo, 5500 Mendoza, Argentina and
| | - Cintia C Vaquer
- From the Instituto de Histología y Embriología, CONICET, Facultad de Ciencias Médicas, CC56, Universidad Nacional de Cuyo, 5500 Mendoza, Argentina and
| | - Matías A Bustos
- From the Instituto de Histología y Embriología, CONICET, Facultad de Ciencias Médicas, CC56, Universidad Nacional de Cuyo, 5500 Mendoza, Argentina and
| | - Gerardo A De Blas
- From the Instituto de Histología y Embriología, CONICET, Facultad de Ciencias Médicas, CC56, Universidad Nacional de Cuyo, 5500 Mendoza, Argentina and
| | - Nicolas Vitale
- the Département Neurotransmission et Sécrétion Neuroendocrine, Institut des Neurosciences Cellulaires et Intégratives (UPR 3212), CNRS et Université de Strasbourg, 5 Rue Blaise Pascal, 67084 Strasbourg, France
| | - Luis S Mayorga
- From the Instituto de Histología y Embriología, CONICET, Facultad de Ciencias Médicas, CC56, Universidad Nacional de Cuyo, 5500 Mendoza, Argentina and
| | - Silvia A Belmonte
- From the Instituto de Histología y Embriología, CONICET, Facultad de Ciencias Médicas, CC56, Universidad Nacional de Cuyo, 5500 Mendoza, Argentina and
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Weber N, Vieweg L, Henze F, Oprisoreanu AM, Solinski HJ, Breit A, Fecher-Trost C, Schalkowsky P, Wilhelm B, Wennemuth G, Schoch S, Gudermann T, Boekhoff I. RIM2α is a molecular scaffold for Zona pellucida-induced acrosome reaction. J Mol Cell Biol 2014; 6:434-7. [DOI: 10.1093/jmcb/mju037] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Ruete MC, Lucchesi O, Bustos MA, Tomes CN. Epac, Rap and Rab3 act in concert to mobilize calcium from sperm's acrosome during exocytosis. Cell Commun Signal 2014; 12:43. [PMID: 25159528 PMCID: PMC4156617 DOI: 10.1186/s12964-014-0043-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2014] [Accepted: 06/19/2014] [Indexed: 11/11/2022] Open
Abstract
Background Exocytosis of sperm’s single secretory granule or acrosome (acrosome reaction, AR) is a highly regulated event essential for fertilization. The AR begins with an influx of calcium from the extracellular milieu and continues with the synthesis of cAMP and the activation of its target Epac. The cascade bifurcates into a Rab3-GTP-driven limb that assembles the fusion machinery and a Rap-GTP-driven limb that mobilizes internal calcium. Results To understand the crosstalk between the two signaling cascades, we applied known AR inhibitors in three experimental approaches: reversible, stage-specific blockers in a functional assay, a far-immunofluorescence protocol to detect active Rab3 and Rap, and single cell-confocal microscopy to visualize fluctuations in internal calcium stores. Our model system was human sperm with their plasma membrane permeabilized with streptolysin O and stimulated with external calcium. The inhibition caused by reagents that prevented the activation of Rap was reversed by mobilizing intracellular calcium pharmacologically, whereas that caused by AR inhibitors that impeded Rab3’s binding to GTP was not. Both limbs of the exocytotic cascade joined at or near the stage catalyzed by Rab3 in a unidirectional, hierarchical connection in which the intra-acrosomal calcium mobilization arm was subordinated to the fusion protein arm; somewhere after Rab3, the pathways became independent. Conclusions We delineated the sequence of events that connect an external calcium signal to internal calcium mobilization during exocytosis. We have taken advantage of the versatility of the sperm model to investigate how cAMP, calcium, and the proteinaceous fusion machinery coordinate to accomplish secretion. Because the requirement of calcium from two different sources is not unique to sperm and fusion proteins are highly conserved, our findings might contribute to elucidate mechanisms that operate in regulated exocytosis in other secretory cell types. Electronic supplementary material The online version of this article (doi:10.1186/s12964-014-0043-0) contains supplementary material, which is available to authorized users.
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Buffone MG, Wertheimer EV, Visconti PE, Krapf D. Central role of soluble adenylyl cyclase and cAMP in sperm physiology. Biochim Biophys Acta Mol Basis Dis 2014; 1842:2610-20. [PMID: 25066614 DOI: 10.1016/j.bbadis.2014.07.013] [Citation(s) in RCA: 146] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2014] [Revised: 07/16/2014] [Accepted: 07/17/2014] [Indexed: 11/15/2022]
Abstract
Cyclic adenosine 3',5'-monophosphate (cAMP), the first second messenger to be described, plays a central role in cell signaling in a wide variety of cell types. Over the last decades, a wide body of literature addressed the different roles of cAMP in cell physiology, mainly in response to neurotransmitters and hormones. cAMP is synthesized by a wide variety of adenylyl cyclases that can generally be grouped in two types: transmembrane adenylyl cyclase and soluble adenylyl cyclases. In particular, several aspects of sperm physiology are regulated by cAMP produced by a single atypical adenylyl cyclase (Adcy10, aka sAC, SACY). The signature that identifies sAC among other ACs, is their direct stimulation by bicarbonate. The essential nature of cAMP in sperm function has been demonstrated using gain of function as well as loss of function approaches. This review unifies state of the art knowledge of the role of cAMP and those enzymes involved in cAMP signaling pathways required for the acquisition of fertilizing capacity of mammalian sperm. This article is part of a Special Issue entitled: The role of soluble adenylyl cyclase in health and disease.
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Affiliation(s)
- Mariano G Buffone
- Instituto de Biología y Medicina Experimental, National Research Council of Argentina (CONICET), Buenos Aires, Argentina
| | - Eva V Wertheimer
- Centro de Estudios Farmacológicos y Botánicos (CEFYBO), Facultad de Medicina, Universidad de Buenos Aires, Argentina
| | - Pablo E Visconti
- Department of Veterinary and Animal Sciences, ISB, University of Massachusetts, Amherst, MA 01003, USA.
| | - Dario Krapf
- Instituto de Biología Molecular y Celular de Rosario (CONICET), UNR, Rosario, Argentina; Facultad de Ciencias Bioquímicas y Farmacéuticas, UNR, Rosario, Argentina
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Harayama H. Roles of intracellular cyclic AMP signal transduction in the capacitation and subsequent hyperactivation of mouse and boar spermatozoa. J Reprod Dev 2014; 59:421-30. [PMID: 24162806 PMCID: PMC3934125 DOI: 10.1262/jrd.2013-056] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
It is not until accomplishment of a variety of molecular changes during the transit
through the female reproductive tract that mammalian spermatozoa are capable of
exhibiting highly activated motility with asymmetric whiplash beating of the flagella
(hyperactivation) and undergoing acrosomal exocytosis in the head (acrosome
reaction). These molecular changes of the spermatozoa are collectively termed
capacitation and promoted by bicarbonate, calcium and cholesterol acceptors. Such
capacitation-promoting factors can stimulate intracellular cyclic AMP (cAMP) signal
transduction in the spermatozoa. Meanwhile, hyperactivation and the acrosome reaction
are essential to sperm fertilization with oocytes and are apparently triggered by a
sufficient increase of intracellular Ca2+ in the sperm flagellum and head,
respectively. Thus, it is necessary to investigate the relationship between cAMP
signal transduction and calcium signaling cascades in the spermatozoa for the purpose
of understanding the molecular basis of capacitation. In this review, I cover updated
insights regarding intracellular cAMP signal transduction, the acrosome reaction and
flagellar motility in mammalian spermatozoa and then account for possible roles of
intracellular cAMP signal transduction in the capacitation and subsequent
hyperactivation of mouse and boar spermatozoa.
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Affiliation(s)
- Hiroshi Harayama
- Laboratory of Reproductive Biology, Graduate School of Agricultural Science, Kobe University, Kobe 657-8501, Japan
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Buffone MG, Hirohashi N, Gerton GL. Unresolved questions concerning mammalian sperm acrosomal exocytosis. Biol Reprod 2014; 90:112. [PMID: 24671881 DOI: 10.1095/biolreprod.114.117911] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
In recent years, the study of mammalian acrosomal exocytosis has produced some major advances that challenge the long-held, general paradigms in the field. Principally, the idea that sperm must be acrosome-intact to bind to the zona pellucida of unfertilized eggs, based largely on in vitro fertilization studies of mouse oocytes denuded of the cumulus oophorus, has been overturned by experiments using state-of-the-art imaging of cumulus-intact oocytes and fertilization experiments where eggs were reinseminated by acrosome-reacted sperm recovered from the perivitelline space of zygotes. In light of these results, this minireview highlights a number of unresolved questions and emphasizes the fact that there is still much work to be done in this exciting field. Future experiments using recently advanced technologies should lead to a more complete and accurate understanding of the molecular mechanisms governing the fertilization process in mammals.
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Affiliation(s)
- Mariano G Buffone
- Instituto de Biologia y Medicina Experimental, National Research Council of Argentina (CONICET), Buenos Aires, Argentina
| | - Noritaka Hirohashi
- Oki Marine Biological Station, Education and Research Center for Biological Resources, Shimane University, Shimane, Japan
| | - George L Gerton
- Center for Research on Reproduction and Women's Health, Department of Obstetrics and Gynecology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania
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