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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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2
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Nir U, Grinshtain E, Breitbart H. Fer and FerT: A New Regulatory Link between Sperm and Cancer Cells. Int J Mol Sci 2023; 24:ijms24065256. [PMID: 36982326 PMCID: PMC10049441 DOI: 10.3390/ijms24065256] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2022] [Revised: 02/12/2023] [Accepted: 03/06/2023] [Indexed: 03/12/2023] Open
Abstract
Fer and its sperm and cancer specific variant, FerT, are non-receptor tyrosine kinases which play roles in cancer progression and metastasis. Recent studies have shed light on the regulatory role of these kinases in ensuring proper sperm function. Comparison of the regulatory cascades in which Fer and FerT are engaged in sperm and cancer cells presents an interesting picture, in which similar regulatory interactions of these enzymes are integrated in a similar or different regulatory context in the two cell types. These diverse compositions extend from the involvement of Fer in modulation of actin cytoskeleton integrity and function, to the unique regulatory interactions of Fer with PARP-1 and the PP1 phosphatase. Furthermore, recent findings link the metabolic regulatory roles of Fer and FerT in sperm and cancer cells. In the current review, we discuss the above detailed aspects, which portray Fer and FerT as new regulatory links between sperm and malignant cells. This perspective view can endow us with new analytical and research tools that will deepen our understanding of the regulatory trajectories and networks that govern these two multi-layered systems.
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3
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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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4
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Grinshtain E, Shpungin S, Baum M, Nir U, Breitbart H. The Fer tyrosine kinase protects sperm from spontaneous acrosome reaction. Dev Biol 2022; 487:24-33. [DOI: 10.1016/j.ydbio.2022.04.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Revised: 03/23/2022] [Accepted: 04/13/2022] [Indexed: 11/24/2022]
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5
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Yamatoya K, Kousaka M, Ito C, Nakata K, Hatano M, Araki Y, Toshimori K. Cleavage of SPACA1 regulates assembly of sperm-egg membrane fusion machinery in mature spermatozoa†. Biol Reprod 2021; 102:750-757. [PMID: 31836887 DOI: 10.1093/biolre/ioz223] [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: 07/24/2019] [Revised: 11/12/2019] [Accepted: 12/11/2019] [Indexed: 01/19/2023] Open
Abstract
The acrosome reaction is a multi-step event essential for physiological fertilization. During the acrosome reaction, gamete fusion-related factor IZUMO1 translocates from the anterior acrosome to the equatorial segment and assembles the gamete fusion machinery. The morphological changes in the acrosome reaction process have been well studied, but little is known about the molecular mechanisms of acrosome reorganization essential for physiological gamete membrane fusion. To elucidate the molecular mechanisms of IZUMO1 translocation, the steps of the acrosome reaction during that process must be clarified. In this study, we established a method to detect the early steps of the acrosome reaction and subdivided the process into seven populations through the use of two epitope-defined antibodies, anti-IZUMO1 and anti-SPACA1, a fertilization-inhibiting antibody. We found that part of the SPACA1 C-terminus in the periacrosomal space was cleaved and had begun to disappear when the vesiculation of the anterior acrosome occurred. The IZUMO1 epitope externalized from the acrosomal lumen before acrosomal vesiculation and phosphorylation of IZUMO1 occurred during the translocation to the equatorial segment. IZUMO1 circumvented the area of the equatorial segment where the SPACA1C-terminus was still localized. We therefore propose an IZUMO1 translocation model and involvement of SPACA1.
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Affiliation(s)
- Kenji Yamatoya
- Institute for Environmental and Gender-Specific Medicine, Juntendo University Graduate School of Medicine, Urayasu, Chiba, Japan.,Department of Applied Biological Science, Faculty of Science and Technology, Tokyo University of Science, Noda, Chiba, Japan.,Department of Reproductive Biology and Medicine, Graduate School of Medicine, Chiba University, Chuo-ku, Chiba, Japan.,Biomedical Research Center, Chiba University, Chuo-ku, Chiba, Japan
| | - Marika Kousaka
- Department of Applied Biological Science, Faculty of Science and Technology, Tokyo University of Science, Noda, Chiba, Japan
| | - Chizuru Ito
- Department of Reproductive Biology and Medicine, Graduate School of Medicine, Chiba University, Chuo-ku, Chiba, Japan.,Department of Functional Anatomy, Reproductive Biology and Medicine, Graduate School of Medicine, Chiba University, Chuo-ku, Chiba, Japan
| | - Kazuya Nakata
- Department of Applied Biological Science, Faculty of Science and Technology, Tokyo University of Science, Noda, Chiba, Japan.,Graduate School of Bio-Applications and Systems Engineering, Tokyo University of Agriculture and Technology, Koganei, Tokyo, Japan and
| | - Masahiko Hatano
- Biomedical Research Center, Chiba University, Chuo-ku, Chiba, Japan
| | - Yoshihiko Araki
- Institute for Environmental and Gender-Specific Medicine, Juntendo University Graduate School of Medicine, Urayasu, Chiba, Japan
| | - Kiyotaka Toshimori
- Department of Reproductive Biology and Medicine, Graduate School of Medicine, Chiba University, Chuo-ku, Chiba, Japan.,Future Medicine Research Center, Chiba University, Chuo-ku, Chiba, Japan
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Li YY, Jia YP, Duan LY, Li KM. Participation of the inositol 1,4,5-trisphosphate-gated calcium channel in the zona pellucida- and progesterone-induced acrosome reaction and calcium influx in human spermatozoa. Asian J Androl 2021; 22:192-199. [PMID: 31169139 PMCID: PMC7155789 DOI: 10.4103/aja.aja_44_19] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
The acrosome reaction is a prerequisite for fertilization, and its signaling pathway has been investigated for decades. Regardless of the type of inducers present, the acrosome reaction is ultimately mediated by the elevation of cytosolic calcium. Inositol 1,4,5-trisphosphate-gated calcium channels are important components of the acrosome reaction signaling pathway and have been confirmed by several researchers. In this study, we used a novel permeabilization tool BioPORTER® and first demonstrated its effectiveness in spermatozoa. The inositol 1,4,5-trisphosphate type-1 receptor antibody was introduced into spermatozoa by BioPORTER® and significantly reduced the calcium influx and acrosome reaction induced by progesterone, solubilized zona pellucida, and the calcium ionophore A23187. This finding indicates that the inositol 1,4,5-trisphosphate type-1 receptor antibody is a valid inositol 1,4,5-trisphosphate receptor inhibitor and provides evidence of inositol 1,4,5-trisphosphate-gated calcium channel involvement in the acrosome reaction in human spermatozoa. Moreover, we demonstrated that the transfer of 1,4,5-trisphosphate into spermatozoa induced acrosome reactions, which provides more reliable evidence for this process. In addition, by treating the spermatozoa with inositol 1,4,5-trisphosphate/BioPORTER® in the presence or absence of calcium in the culture medium, we showed that the opening of inositol 1,4,5-trisphosphate-gated calcium channels led to extracellular calcium influx. This particular extracellular calcium influx may be the major process of the final step of the acrosome reaction signaling pathway.
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Affiliation(s)
- Ying-Ya Li
- Center of Reproductive Medicine, Shanghai First Maternity and Infant Hospital, Tongji University School of Medicine, Shanghai 201204, China
| | - Yan-Ping Jia
- Center of Reproductive Medicine, Shanghai First Maternity and Infant Hospital, Tongji University School of Medicine, Shanghai 201204, China
| | - Li-Yan Duan
- Center of Reproductive Medicine, Shanghai First Maternity and Infant Hospital, Tongji University School of Medicine, Shanghai 201204, China
| | - Kun-Ming Li
- Center of Reproductive Medicine, Shanghai First Maternity and Infant Hospital, Tongji University School of Medicine, Shanghai 201204, China
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The Role of Zinc in Male Fertility. Int J Mol Sci 2020; 21:ijms21207796. [PMID: 33096823 PMCID: PMC7589359 DOI: 10.3390/ijms21207796] [Citation(s) in RCA: 51] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Revised: 10/14/2020] [Accepted: 10/20/2020] [Indexed: 12/18/2022] Open
Abstract
Several studies proposed the importance of zinc ion in male fertility. Here, we describe the properties, roles and cellular mechanisms of action of Zn2+ in spermatozoa, focusing on its involvement in sperm motility, capacitation and acrosomal exocytosis, three functions that are crucial for successful fertilization. The impact of zinc supplementation on assisted fertilization techniques is also described. The impact of zinc on sperm motility has been investigated in many vertebrate and invertebrate species. It has been reported that Zn2+ in human seminal plasma decreases sperm motility and that Zn2+ removal enhances motility. Reduction in the intracellular concentration of Zn2+ during epididymal transit allows the development of progressive motility and the subsequent hyper activated motility during sperm capacitation. Extracellular Zn2+ affects intracellular signaling pathways through its interaction with the Zn2+ sensing receptor (ZnR), also named GPR39. This receptor was found in the sperm tail and the acrosome, suggesting the possible involvement of Zn2+ in sperm motility and acrosomal exocytosis. Our studies showed that Zn2+ stimulates bovine sperm acrosomal exocytosis, as well as human sperm hyper-activated motility, were both mediated by GPR39. Zn2+ binds and activates GPR39, which activates the trans-membrane-adenylyl-cyclase (tmAC) to catalyze cAMP production. The NHE (Na+/H+-exchanger) is activated by cAMP, leading in increased pHi and activation of the sperm-specific Ca2+ channel CatSper, resulting in an increase in [Ca2+]i, which, together with HCO3−, activates the soluble adenylyl-cyclase (sAC). The increase in [cAMP]i activates protein kinase A (PKA), followed by activation of the Src-epidermal growth factor receptor-Pphospholipase C (Src-EGFR-PLC) cascade, resulting in inositol-triphosphate (IP3) production, which mobilizes Ca2+ from the acrosome, causing a further increase in [Ca2+]i and the development of hyper-activated motility. PKA also activates phospholipase D1 (PLD1), leading to F-actin formation during capacitation. Prior to the acrosomal exocytosis, PLC induces phosphadidylinositol-4,5-bisphosphate (PIP2) hydrolysis, leading to the release of the actin-severing protein gelsolin to the cytosol, which is activated by Ca2+, resulting in F-actin breakdown and the occurrence of acrosomal exocytosis.
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8
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Finkelstein M, Etkovitz N, Breitbart H. Ca 2+ signaling in mammalian spermatozoa. Mol Cell Endocrinol 2020; 516:110953. [PMID: 32712383 DOI: 10.1016/j.mce.2020.110953] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/08/2020] [Revised: 06/08/2020] [Accepted: 07/20/2020] [Indexed: 02/06/2023]
Abstract
Calcium is an essential ion which regulates sperm motility, capacitation and the acrosome reaction (AR), three processes necessary for successful fertilization. The AR enables the spermatozoon to penetrate into the egg. In order to undergo the AR, the spermatozoon must reside in the female reproductive tract for several hours, during which a series of biochemical transformations takes place, collectively called capacitation. An early event in capacitation is relatively small elevation of intracellular Ca2+ (in the nM range) and bicarbonate, which collectively activate the soluble adenylyl cyclase to produce cyclic-AMP; c-AMP activates protein kinase A (PKA), leading to indirect tyrosine phosphorylation of proteins. During capacitation, there is an increase in the membrane-bound phospholipase C (PLC) which is activated prior to the AR by relatively high increase in intracellular Ca2+ (in the μM range). PLC catalyzes the hydrolysis of phosphatidyl-inositol-4,5-bisphosphate (PIP2) to diacylglycerol and inositol-trisphosphate (IP3), leading to activation of protein kinase C (PKC) and the IP3-receptor. PKC activates a Ca2+- channel in the plasma membrane, and IP3 activates the Ca2+- channel in the outer acrosomal membrane, leading to Ca2+ depletion from the acrosome. As a result, the plasma-membrane store-operated Ca2+ channel (SOCC) is activated to increase cytosolic Ca2+ concentration, enabling completion of the acrosome reaction. The hydrolysis of PIP2 by PLC results in the release and activation of PIP2-bound gelsolin, leading to F-actin dispersion, an essential step prior to the AR. Ca2+ is also involved in the regulation of sperm motility. During capacitation, the sperm develops a unique motility pattern called hyper-activated motility (HAM) which is essential for successful fertilization. The main Ca2+-channel that mediates HAM is the sperm-specific CatSper located in the sperm tail.
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Affiliation(s)
| | - Nir Etkovitz
- Sperm Bank, Sheba Hospital, Tel-Hashomer, Israel
| | - Haim Breitbart
- The Mina & Everard Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, 5290002, Israel.
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9
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Huta Y, Nitzan Y, Breitbart H. Ezrin protects bovine spermatozoa from spontaneous acrosome reaction. Theriogenology 2020; 151:119-127. [PMID: 32334120 DOI: 10.1016/j.theriogenology.2020.04.019] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2019] [Revised: 04/12/2020] [Accepted: 04/13/2020] [Indexed: 11/18/2022]
Abstract
To interact and penetrate the egg, the spermatozoon must undergo a maturation step called the acrosome reaction (AR) in close proximity to the egg. This process can take place only after a series of biochemical changes to the sperm occur in the female reproductive tract, collectively called capacitation. Spermatozoa can undergo spontaneous-acrosome reaction (sAR) before reaching the vicinity of the egg, preventing successful fertilization. Several mechanisms were shown to protect spermatozoa from undergoing sAR. Here we describe the involvement of the actin cross-linker, Ezrin in the mechanism that protects spermatozoa from sAR. Inhibition of Ezrin stimulates sAR and inhibits actin polymerization. Ezrin is highly phosphorylated/activated during the first hour of the capacitation process, and its phosphorylation rate is subsequently decreased. Ezrin phosphorylation depends on protein kinase A (PKA) and calmodulin kinase II (CaMKII) activities, and to some extent on phosphatidyl-inositol-4-kinase (PI4K) activity. Inhibition of these three kinases stimulates sAR, in which the effect of PI4K inhibition, but not PKA or CaMKII inhibition, can be reversed by increasing p-Ezrin using a phosphatase inhibitor. All together, we showed that three kinases mediate Ezrin activation during spermatozoa capacitation, leading to actin polymerization in a mechanism that prevents sAR.
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Affiliation(s)
- Y Huta
- The Mina &Everard Faculty of Life Sciences,Bar-Ilan University, Ramat-Gan, 5290002, Israel
| | - Y Nitzan
- Department of Clinical Laboratory Science, Zefat Academic College, Zefat, 1320611, Israel
| | - H Breitbart
- The Mina &Everard Faculty of Life Sciences,Bar-Ilan University, Ramat-Gan, 5290002, Israel.
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10
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Al-Jezawi NK, Al-Shamsi AM, Suleiman J, Ben-Salem S, John A, Vijayan R, Ali BR, Al-Gazali L. Compound heterozygous variants in the multiple PDZ domain protein (MPDZ) cause a case of mild non-progressive communicating hydrocephalus. BMC MEDICAL GENETICS 2018; 19:34. [PMID: 29499638 PMCID: PMC5834892 DOI: 10.1186/s12881-018-0540-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/23/2017] [Accepted: 02/12/2018] [Indexed: 02/08/2023]
Abstract
Background Congenital hydrocephalus (CH) results from the accumulation of excessive amounts of cerebrospinal fluid (CSF) in the brain, often leading to severe neurological impairments. However, the adverse effects of CH can be reduced if the condition is detected and treated early. Earlier reports demonstrated that some CH cases are caused by mutations in L1CAM gene encoding the neural cell adhesion molecule L1. On the other hand, recent studies have implicated the multiple PDZ domain (MPDZ) gene in some severe forms of CH, inherited in an autosomal recessive pattern. Methods In this study, whole-exome and Sanger sequencing were performed on a 9 months old Emirati child clinically diagnosed by CH. In addition, in silico, cellular, and molecular assays have been conducted to confirm pathogenicity of the identified variants and to establish disease mechanism. Results Whole exome sequencing revealed two compound heterozygous novel variants (c.394G > A and c.1744C > G) in the affected child within the MPDZ gene. Segregation analysis revealed that each of the parents is heterozygous for one of the two variants and therefore passed that variant to their child. The outcome of the in silico and bioinformatics analyses came in line with the experimental data, suggesting that the two variants are most likely disease causing. Conclusions The compound heterozygous variants identified in this study are the most likely cause of CH in the affected child. The study further confirms MPDZ as a gene underlying some CH cases.
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Affiliation(s)
- Nesreen K Al-Jezawi
- Department of Pathology, College of Medicine and Heath Sciences, United Arab Emirates University, P.O. Box 17666, Al-Ain, United Arab Emirates
| | - Aisha M Al-Shamsi
- Department of Paediatrics, Tawam Hospital, Al-Ain, United Arab Emirates
| | - Jehan Suleiman
- Department of Paediatrics, College of Medicine and Heath Sciences, United Arab Emirates University, P.O. Box 17666, Al-Ain, United Arab Emirates
| | - Salma Ben-Salem
- Department of Pathology, College of Medicine and Heath Sciences, United Arab Emirates University, P.O. Box 17666, Al-Ain, United Arab Emirates
| | - Anne John
- Department of Pathology, College of Medicine and Heath Sciences, United Arab Emirates University, P.O. Box 17666, Al-Ain, United Arab Emirates
| | - Ranjit Vijayan
- Department of Biology, College of Science, United Arab Emirates University, Al Ain, United Arab Emirates
| | - Bassam R Ali
- Department of Pathology, College of Medicine and Heath Sciences, United Arab Emirates University, P.O. Box 17666, Al-Ain, United Arab Emirates.
| | - Lihadh Al-Gazali
- Department of Paediatrics, College of Medicine and Heath Sciences, United Arab Emirates University, P.O. Box 17666, Al-Ain, United Arab Emirates.
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Wang J, Guo Y, Zhang X. Design and verification of halogen-bonding system at the complex interface of human fertilization-related MUP PDZ5 domain with CAMK’s C-terminal peptide. Comput Biol Chem 2018; 72:164-169. [DOI: 10.1016/j.compbiolchem.2017.11.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2017] [Revised: 11/09/2017] [Accepted: 11/19/2017] [Indexed: 10/18/2022]
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12
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Zhang YL, Han ZF. Rational design of an orthogonal noncovalent interaction system at the MUPP1 PDZ11 complex interface with CaMKIIα-derived peptides in human fertilization. MOLECULAR BIOSYSTEMS 2017; 13:2145-2151. [PMID: 28832060 DOI: 10.1039/c7mb00379j] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
An orthogonal noncovalent interaction (ONI) system between a native hydrogen bond and a designed halogen bond across the complex interface of the MUPP1 PDZ11 domain with the CaMKIIαsia[Asn-1Phe] peptide mutant is introduced using a structure-based rational approach.
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Affiliation(s)
- Yi-Le Zhang
- Reproductive Medical Center
- the First Affiliated Hospital of Zhengzhou University
- Zhengzhou 450052
- China
| | - Zhao-Feng Han
- Department of Burn and Reconstruction Surgery
- the First Affiliated Hospital of Zhengzhou University
- Zhengzhou 450052
- China
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13
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Involvement of Tight Junction Plaque Proteins in Cancer. CURRENT PATHOBIOLOGY REPORTS 2016. [DOI: 10.1007/s40139-016-0108-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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14
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Shabtay O, Breitbart H. CaMKII prevents spontaneous acrosomal exocytosis in sperm through induction of actin polymerization. Dev Biol 2016; 415:64-74. [PMID: 27178669 DOI: 10.1016/j.ydbio.2016.05.008] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2016] [Revised: 05/08/2016] [Accepted: 05/09/2016] [Indexed: 02/01/2023]
Abstract
In order to interact with the egg and undergo acrosomal exocytosis or the acrosome reaction (AR), mammalian spermatozoa must undergo a series of biochemical changes in the female reproductive tract, collectively called capacitation. We showed that F-actin is formed during sperm capacitation and fast depolymerization occurs prior to the AR. We hypothesized that F-actin protects the sperm from undergoing spontaneous-AR (sAR) which decreases fertilization rate. We show that activation of the actin-severing protein gelsolin induces a significant increase in sAR. Moreover, inhibition of CaMKII or PLD during sperm capacitation, caused an increase in sAR and inhibition of F-actin formation. Spermine, which leads to PLD activation, was able to reverse the effects of CaMKII inhibition on sAR-increase and F-actin-decrease. Furthermore, the increase in sAR and the decrease in F-actin caused by the inactivation of the PLD-pathway, were reversed by activation of CaMKII using H2O2 or by inhibiting protein phosphatase 1 which enhance the phosphorylation and oxidation states of CaMKII. These results indicate that two distinct pathways lead to F-actin formation in the sperm capacitation process which prevents the occurrence of sAR.
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Affiliation(s)
- Ortal Shabtay
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 5290002, Israel
| | - Haim Breitbart
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 5290002, Israel.
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15
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Donaldson R, Sun Y, Liang DY, Zheng M, Sahbaie P, Dill DL, Peltz G, Buck KJ, Clark JD. The multiple PDZ domain protein Mpdz/MUPP1 regulates opioid tolerance and opioid-induced hyperalgesia. BMC Genomics 2016; 17:313. [PMID: 27129385 PMCID: PMC4850636 DOI: 10.1186/s12864-016-2634-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Accepted: 04/22/2016] [Indexed: 01/05/2023] Open
Abstract
BACKGROUND Opioids are a mainstay for the treatment of chronic pain. Unfortunately, therapy-limiting maladaptations such as loss of treatment effect (tolerance), and paradoxical opioid-induced hyperalgesia (OIH) can occur. The objective of this study was to identify genes responsible for opioid tolerance and OIH. RESULTS These studies used a well-established model of ascending morphine administration to induce tolerance, OIH and other opioid maladaptations in 23 strains of inbred mice. Genome-wide computational genetic mapping was then applied to the data in combination with a false discovery rate filter. Transgenic mice, gene expression experiments and immunoprecipitation assays were used to confirm the functional roles of the most strongly linked gene. The behavioral data processed using computational genetic mapping and false discovery rate filtering provided several strongly linked biologically plausible gene associations. The strongest of these was the highly polymorphic Mpdz gene coding for the post-synaptic scaffolding protein Mpdz/MUPP1. Heterozygous Mpdz +/- mice displayed reduced opioid tolerance and OIH. Mpdz gene expression and Mpdz/MUPP1 protein levels were lower in the spinal cords of low-adapting 129S1/Svlm mice than in high-adapting C57BL/6 mice. Morphine did not alter Mpdz expression levels. In addition, association of Mpdz/MUPP1 with its known binding partner CaMKII did not differ between these high- and low-adapting strains. CONCLUSIONS The degrees of maladaptive changes in response to repeated administration of morphine vary greatly across inbred strains of mice. Variants of the multiple PDZ domain gene Mpdz may contribute to the observed inter-strain variability in tolerance and OIH by virtue of changes in the level of their expression.
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Affiliation(s)
- Robin Donaldson
- Department of Computer Science, Stanford University, Stanford, CA, USA
| | - Yuan Sun
- Anesthesiology Service, Veterans Affairs Palo Alto Health Care System, 3801 Miranda Ave., Anesthesiology, 112A, Palo Alto, CA, 94304, USA.,Department of Anesthesiology, Perioperative and Pain Medicine, Stanford University School of Medicine, Stanford, CA, USA
| | - De-Yong Liang
- Anesthesiology Service, Veterans Affairs Palo Alto Health Care System, 3801 Miranda Ave., Anesthesiology, 112A, Palo Alto, CA, 94304, USA.,Department of Anesthesiology, Perioperative and Pain Medicine, Stanford University School of Medicine, Stanford, CA, USA
| | - Ming Zheng
- Department of Anesthesiology, Perioperative and Pain Medicine, Stanford University School of Medicine, Stanford, CA, USA
| | - Peyman Sahbaie
- Anesthesiology Service, Veterans Affairs Palo Alto Health Care System, 3801 Miranda Ave., Anesthesiology, 112A, Palo Alto, CA, 94304, USA.,Department of Anesthesiology, Perioperative and Pain Medicine, Stanford University School of Medicine, Stanford, CA, USA
| | - David L Dill
- Department of Computer Science, Stanford University, Stanford, CA, USA
| | - Gary Peltz
- Department of Anesthesiology, Perioperative and Pain Medicine, Stanford University School of Medicine, Stanford, CA, USA
| | - Kari J Buck
- Department of Behavioral Neuroscience, Oregon Health and Science University, Portland, OR, USA
| | - J David Clark
- Anesthesiology Service, Veterans Affairs Palo Alto Health Care System, 3801 Miranda Ave., Anesthesiology, 112A, Palo Alto, CA, 94304, USA. .,Department of Anesthesiology, Perioperative and Pain Medicine, Stanford University School of Medicine, Stanford, CA, USA.
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Structure-based identification of CaMKIIα-interacting MUPP1 PDZ domains and rational design of peptide ligands to target such interaction in human fertilization. Amino Acids 2016; 48:1509-21. [DOI: 10.1007/s00726-016-2211-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2015] [Accepted: 02/29/2016] [Indexed: 01/15/2023]
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17
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Borth H, Weber N, Meyer D, Wartenberg A, Arlt E, Zierler S, Breit A, Wennemuth G, Gudermann T, Boekhoff I. The IP3 R Binding Protein Released With Inositol 1,4,5-Trisphosphate Is Expressed in Rodent Reproductive Tissue and Spermatozoa. J Cell Physiol 2015; 231:1114-29. [PMID: 26439876 DOI: 10.1002/jcp.25209] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2015] [Accepted: 09/30/2015] [Indexed: 11/08/2022]
Abstract
Besides its capacity to inhibit the 1,4,5-trisphosphate (IP3) receptor, the regulatory protein IRBIT (IP3 receptor binding protein released with IP3) is also able to control the activity of numerous ion channels and electrolyte transporters and thereby creates an optimal electrolyte composition of various biological fluids. Since a reliable execution of spermatogenesis and sperm maturation critically depends on the establishment of an adequate microenvironment, the expression of IRBIT in male reproductive tissue was examined using immunohistochemical approaches combined with biochemical fractionation methods. The present study documents that IRBIT is expressed in Leydig and Sertoli cells. In addition, pronounced IRBIT expression was detected in sperm precursors during early stages of spermatogenesis as well as in spermatozoa. Analyzing tissue sections of rodent epididymides, IRBIT was found to co-localize with the proton pumping V-ATPase and the cystic fibrosis transmembrane conductance regulator (CFTR) at the apical surface of narrow and clear cells. A similar co-localization of IRBIT with CFTR was also observed for Sertoli cells and developing germ cells. Remarkably, assaying caudal sperm in immunogold electron microscopy, IRBIT was found to localize to the acrosomal cap and the flagellum as well as to the sperm nucleus; moreover, a prominent oligomerization was observed for spermatozoa. The pronounced occurrence of IRBIT in the male reproductive system and mature spermatozoa indicates a potential role for IRBIT in establishing the essential luminal environment for a faithful execution of spermatogenesis and epididymal sperm maturation, and suggest a participation of IRBIT during maturation steps after ejaculation and/or the final fertilization process.
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Affiliation(s)
- Heike Borth
- Walther Straub Institute of Pharmacology and Toxicology, Ludwig-Maximilians-Universit, ä, t M, ü, nchen, München, Germany
| | - Nele Weber
- Walther Straub Institute of Pharmacology and Toxicology, Ludwig-Maximilians-Universit, ä, t M, ü, nchen, München, Germany
| | - Dorke Meyer
- Walther Straub Institute of Pharmacology and Toxicology, Ludwig-Maximilians-Universit, ä, t M, ü, nchen, München, Germany
| | - Andrea Wartenberg
- Walther Straub Institute of Pharmacology and Toxicology, Ludwig-Maximilians-Universit, ä, t M, ü, nchen, München, Germany
| | - Elisabeth Arlt
- Walther Straub Institute of Pharmacology and Toxicology, Ludwig-Maximilians-Universit, ä, t M, ü, nchen, München, Germany
| | - Susanna Zierler
- Walther Straub Institute of Pharmacology and Toxicology, Ludwig-Maximilians-Universit, ä, t M, ü, nchen, München, Germany
| | - Andreas Breit
- Walther Straub Institute of Pharmacology and Toxicology, Ludwig-Maximilians-Universit, ä, t M, ü, nchen, München, Germany
| | - Gunther Wennemuth
- Department of Anatomy, University Clinic Essen, University of Duisburg-Essen, Germany
| | - Thomas Gudermann
- Walther Straub Institute of Pharmacology and Toxicology, Ludwig-Maximilians-Universit, ä, t M, ü, nchen, München, Germany
| | - Ingrid Boekhoff
- Walther Straub Institute of Pharmacology and Toxicology, Ludwig-Maximilians-Universit, ä, t M, ü, nchen, München, Germany
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18
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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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Simultaneous deletion of floxed genes mediated by CaMKIIα-Cre in the brain and in male germ cells: application to conditional and conventional disruption of Goα. Exp Mol Med 2014; 46:e93. [PMID: 24787734 PMCID: PMC3972788 DOI: 10.1038/emm.2014.14] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2013] [Revised: 12/04/2013] [Accepted: 12/21/2013] [Indexed: 11/08/2022] Open
Abstract
The Cre/LoxP system is a well-established approach to spatially and temporally control genetic inactivation. The calcium/calmodulin-dependent protein kinase II alpha subunit (CaMKIIα) promoter limits expression to specific regions of the forebrain and thus has been utilized for the brain-specific inactivation of the genes. Here, we show that CaMKIIα-Cre can be utilized for simultaneous inactivation of genes in the adult brain and in male germ cells. Double transgenic Rosa26+/stop-lacZ::CaMKIIα-Cre+/Cre mice generated by crossing CaMKIIα-Cre+/Cre mice with floxed ROSA26 lacZ reporter (Rosa26+/stop-lacZ) mice exhibited lacZ expression in the brain and testis. When these mice were mated to wild-type females, about 27% of the offspring were whole body blue by X-gal staining without inheriting the Cre transgene. These results indicate that recombination can occur in the germ cells of male Rosa26+/stop-lacZ::CaMKIIα-Cre+/Cre mice. Similarly, when double transgenic Gnao+/f::CaMKIIα-Cre+/Cre mice carrying a floxed Go-alpha gene (Gnaof/f) were backcrossed to wild-type females, approximately 22% of the offspring carried the disrupted allele (GnaoΔ) without inheriting the Cre transgene. The GnaoΔ/Δ mice closely resembled conventional Go-alpha knockout mice (Gnao−/−) with respect to impairment of their behavior. Thus, we conclude that CaMKIIα-Cre mice afford recombination for both tissue- and time-controlled inactivation of floxed target genes in the brain and for their permanent disruption. This work also emphasizes that extra caution should be exercised in utilizing CaMKIIα-Cre mice as breeding pairs.
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20
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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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21
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Baumgart S, Jansen F, Bintig W, Kalbe B, Herrmann C, Klumpers F, Köster SD, Scholz P, Rasche S, Dooley R, Metzler-Nolte N, Spehr M, Hatt H, Neuhaus EM. The scaffold protein MUPP1 regulates odorant-mediated signaling in olfactory sensory neurons. J Cell Sci 2014; 127:2518-27. [PMID: 24652834 DOI: 10.1242/jcs.144220] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The olfactory signal transduction cascade transforms odor information into electrical signals by a cAMP-based amplification mechanism. The mechanisms underlying the very precise temporal and spatial organization of the relevant signaling components remains poorly understood. Here, we identify, using co-immunoprecipitation experiments, a macromolecular assembly of signal transduction components in mouse olfactory neurons, organized through MUPP1. Disruption of the PDZ signaling complex, through use of an inhibitory peptide, strongly impaired odor responses and changed the activation kinetics of olfactory sensory neurons. In addition, our experiments demonstrate that termination of the response is dependent on PDZ-based scaffolding. These findings provide new insights into the functional organization, and regulation, of olfactory signal transduction.
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Affiliation(s)
- Sabrina Baumgart
- Cell Physiology, Faculty for Biology and Biotechnology, Ruhr-Universität Bochum, Universitätsstrasse 150, 44780 Bochum, Germany
| | - Fabian Jansen
- Cell Physiology, Faculty for Biology and Biotechnology, Ruhr-Universität Bochum, Universitätsstrasse 150, 44780 Bochum, Germany
| | - Willem Bintig
- Cluster of Excellence NeuroCure, Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany
| | - Benjamin Kalbe
- Cell Physiology, Faculty for Biology and Biotechnology, Ruhr-Universität Bochum, Universitätsstrasse 150, 44780 Bochum, Germany
| | - Christian Herrmann
- Physical Chemistry I, Ruhr-Universität Bochum, Universitätsstrasse 150, 44780 Bochum, Germany
| | - Fabian Klumpers
- Physical Chemistry I, Ruhr-Universität Bochum, Universitätsstrasse 150, 44780 Bochum, Germany
| | - S David Köster
- Inorganic Chemistry I - Bioinorganic Chemistry, Ruhr-Universität Bochum, Universitätsstrasse 150, 44780 Bochum, Germany
| | - Paul Scholz
- Cell Physiology, Faculty for Biology and Biotechnology, Ruhr-Universität Bochum, Universitätsstrasse 150, 44780 Bochum, Germany
| | - Sebastian Rasche
- Cell Physiology, Faculty for Biology and Biotechnology, Ruhr-Universität Bochum, Universitätsstrasse 150, 44780 Bochum, Germany
| | - Ruth Dooley
- Department of Molecular Medicine, Royal College of Surgeons in Ireland, Beaumont Hospital, Dublin 9, Ireland
| | - Nils Metzler-Nolte
- Chair of Inorganic Chemistry I - Bioinorganic Chemistry, Ruhr-Universität Bochum, Universitätsstrasse 150, 44780 Bochum, Germany
| | - Marc Spehr
- Department of Chemosensation, Institute for Biology II, RWTH-Aachen University, Worringer Weg 1, 52074 Aachen, Germany
| | - Hanns Hatt
- Cell Physiology, Faculty for Biology and Biotechnology, Ruhr-Universität Bochum, Universitätsstrasse 150, 44780 Bochum, Germany
| | - Eva M Neuhaus
- Cluster of Excellence NeuroCure, Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany Pharmacology and Toxicology, University Hospital Jena, Drakendorfer Weg 1, 07743 Jena, Germany
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22
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Rotfeld H, Hillman P, Ickowicz D, Breitbart H. PKA and CaMKII mediate PI3K activation in bovine sperm by inhibition of the PKC/PP1 cascade. Reproduction 2014; 147:347-56. [DOI: 10.1530/rep-13-0560] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
To enable fertilization, spermatozoa must undergo several biochemical processes in the female reproductive tract, collectively called capacitation. These processes involve protein kinase A (PKA)-dependent protein tyrosine phosphorylation including phosphatidylinositol-3-kinase (PI3K). It is not known how PKA, a serine/threonine (S/T) kinase, mediates tyrosine phosphorylation of proteins. We recently showed that inhibition of S/T phosphatase 1 (PP1) causes a significant increase in phospho-PI3K. In this study, we propose a mechanism by which PKA and PP1 mediate an increase in PI3K tyrosine phosphorylation and implicate calmodulin-dependent kinase II (CaMKII) in this process. Inhibition of sperm PP1 or PKC, stimulated CaMKII phosphorylation/activation, and inhibition of PKC enhanced PP1 phosphorylation/inactivation. Inhibition of CaMKII, using KN-93, caused significant reduction in phospho-PP1, indicating its activation. Moreover, KN-93 prevented the dephosphorylation/inactivation of PKC. We therefore suggest that CaMKII inhibits PKC, leading to PP1 inhibition and the reciprocal auto-activation of CaMKII. Thus, CaMKII can regulate its own activation by inhibiting the PKC/PP1 cascade. Inhibition of Src family kinases (SFK) caused significant inhibition of CaMKII and PP1 phosphorylation, suggesting that SFK activity results in PP1 inhibition and CaMKII activation. Activation of sperm PKA by 8Br-cAMP revealed an increase in phospho-CaMKII, which was inhibited by PKA inhibitor. Tyrosine phosphorylation of PI3K was stimulated by 8Br-cAMP and by PKC or PP1 inhibition and was abrogated by CaMKII inhibition. Furthermore, phosphorylation/activation of the tyrosine kinase Pyk2 was enhanced by PP1 inhibition, and this activation is blocked by CaMKII inhibition. Thus, PKA activates Src, which inhibits PP1, leading to CaMKII and Pyk2 activation, resulting in PI3K tyrosine phosphorylation/activation.
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Hurtado de Llera A, Martin-Hidalgo D, Gil MC, Garcia-Marin LJ, Bragado MJ. The calcium/CaMKKalpha/beta and the cAMP/PKA pathways are essential upstream regulators of AMPK activity in boar spermatozoa. Biol Reprod 2014; 90:29. [PMID: 24389872 DOI: 10.1095/biolreprod.113.112797] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Spermatozoa successfully fertilize oocytes depending on cell energy-sensitive processes. We recently showed that the cell energy sensor, the AMP-activated protein kinase (AMPK), plays a relevant role in spermatozoa by regulating motility as well as plasma membrane organization and acrosomal integrity, and contributes to the maintenance of mitochondrial membrane potential. As the signaling pathways that control AMPK activity have been studied exclusively in somatic cells, our aim is to investigate the intracellular pathways that regulate AMPK phosphorylation at Thr(172) (activity) in male germ cells. Boar spermatozoa were incubated under different conditions in the presence or absence of Ca(2+), 8Br-cAMP, IBMX, PMA, the AMPK activator A769662, or inhibitors of PKA, PKC, or CaMKKalpha/beta. AMPK phosphorylation was evaluated by Western blot using anti-phospho-Thr(172)-AMPK antibody. Data show that AMPK phosphorylation in spermatozoa is potently stimulated by an elevation of cAMP levels through the activation of PKA, as the PKA inhibitor H89 blocks phospho-Thr(172)-AMPK. Another mechanism to potently activate AMPK is Ca(2+) that acts through two pathways, PKA (blocked by H89) and CaMKKalpha/beta (blocked by STO-609). Moreover, phospho-Thr(172)-AMPK levels greatly increased upon PKC activation induced by PMA, and the PKC inhibitor Ro-32-0432 inhibits TCM-induced AMPK activation. Different stimuli considered as cell stresses (rotenone, cyanide, sorbitol, and complete absence of intracellular Ca(2+) by BAPTA-AM) also cause AMPK phosphorylation in spermatozoa. In summary, AMPK activity in boar spermatozoa is regulated upstream by different kinases, such as PKA, CaMKKalpha/beta, and PKC, as well as by the essential intracellular messengers for spermatozoan function, Ca(2+) and cAMP levels.
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Affiliation(s)
- Ana Hurtado de Llera
- Research Group of Intracellular Signaling and Technology of Reproduction, School of Veterinary Medicine, University of Extremadura, Caceres, Spain
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24
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Arndt L, Castonguay J, Arlt E, Meyer D, Hassan S, Borth H, Zierler S, Wennemuth G, Breit A, Biel M, Wahl-Schott C, Gudermann T, Klugbauer N, Boekhoff I. NAADP and the two-pore channel protein 1 participate in the acrosome reaction in mammalian spermatozoa. Mol Biol Cell 2014; 25:948-64. [PMID: 24451262 PMCID: PMC3952862 DOI: 10.1091/mbc.e13-09-0523] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
A TPCN1 gene–deficient mouse strain is used to show that two convergent working NAADP-dependent pathways with nonoverlapping activation and self-inactivation profiles for distinct NAADP concentrations drive acrosomal exocytosis, by which TPC1 is central for the pathway activated by low-micromolar NAADP concentrations. The functional relationship between the formation of hundreds of fusion pores during the acrosome reaction in spermatozoa and the mobilization of calcium from the acrosome has been determined only partially. Hence, the second messenger NAADP, promoting efflux of calcium from lysosome-like compartments and one of its potential molecular targets, the two-pore channel 1 (TPC1), were analyzed for its involvement in triggering the acrosome reaction using a TPCN1 gene–deficient mouse strain. The present study documents that TPC1 and NAADP-binding sites showed a colocalization at the acrosomal region and that treatment of spermatozoa with NAADP resulted in a loss of the acrosomal vesicle that showed typical properties described for TPCs: Registered responses were not detectable for its chemical analogue NADP and were blocked by the NAADP antagonist trans-Ned-19. In addition, two narrow bell-shaped dose-response curves were identified with maxima in either the nanomolar or low micromolar NAADP concentration range, where TPC1 was found to be responsible for activating the low affinity pathway. Our finding that two convergent NAADP-dependent pathways are operative in driving acrosomal exocytosis supports the concept that both NAADP-gated cascades match local NAADP concentrations with the efflux of acrosomal calcium, thereby ensuring complete fusion of the large acrosomal vesicle.
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Affiliation(s)
- Lilli Arndt
- Walther Straub Institute of Pharmacology and Toxicology, Ludwig-Maximilians University, 81377 München, Germany Department of Pharmacy, Ludwig-Maximilians University, 81377 München, Germany Institute for Experimental and Clinical Pharmacology and Toxicology, Albert-Ludwigs-University, 79104 Freiburg, Germany Institute for Anatomy, University of Duisburg-Essen, 45141 Essen, Germany
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Role of posttranslational protein modifications in epididymal sperm maturation and extracellular quality control. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2014; 759:159-80. [PMID: 25030764 DOI: 10.1007/978-1-4939-0817-2_8] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The epididymal lumen is a complex microenvironment in which spermatozoa acquire motility and fertility. Spermatozoa are synthetically inactive and therefore the maturation process requires their interaction with proteins that are synthesized and secreted in a highly regionalized manner by the epididymal epithelium. In addition to the integration of epididymal secretory proteins, posttranslational modifications of existing sperm proteins are important for sperm maturation and acquisition of fertilizing potential. Phosphorylation, glycosylation, and processing are several of the posttranslational modifications that sperm proteins undergo during epididymal transit resulting in changes in protein function and localization ultimately leading to mature spermatozoa. In addition to these well-characterized modifications, protein aggregation and cross-linking also occur within the epididymal lumen and may represent unique mechanisms for controlling protein function including that for maturation as well as for extracellular quality control.
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26
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Rab27 and Rab3 sequentially regulate human sperm dense-core granule exocytosis. Proc Natl Acad Sci U S A 2012; 109:E2057-66. [PMID: 22753498 DOI: 10.1073/pnas.1121173109] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Two so-called "secretory Rabs," Rab3 and Rab27, regulate late steps during dense-core vesicle exocytosis in neuroendocrine cells. Sperm contain a single large dense-core granule that is released by regulated exocytosis (termed the acrosome reaction) during fertilization or on exposure to inducers in vitro. Sperm exocytosis uses the same fusion machinery as neurons and neuroendocrine cells, with an additional requirement for active Rab3. Here we show that Rab27 is also required for the acrosome reaction, as demonstrated by the inability of inducers to elicit exocytosis when streptolysin O-permeabilized human sperm were loaded with inhibitory anti-Rab27 antibodies or the Rab27-GTP binding domain of the effector Slac2-b. The levels of GTP-bound Rab27 increased on initiation of exocytosis, as did the proportion of GTP-bound Rab3A. We have developed a fluorescence microscopy-based method for detecting endogenous Rab3A-GTP and Rab27-GTP in the acrosomal region of human sperm. Challenge with an inducer increased the population of cells exhibiting GTP-bound Rabs in this subcellular domain. Interestingly, introducing recombinant Rab27A loaded with GTP-γ-S into sperm elicited a remarkable increase in the number of cells evincing GTP-bound Rab3A. In the converse condition, recombinant Rab3A did not modify the percentage of Rab27-GTP-containing cells. Furthermore, Rab27A-GTP recruited a Rab3 GDP/GTP exchange factor (GEF) activity. Our findings suggest that Rab27/Rab3A constitutes a Rab-GEF cascade in dense-core vesicle exocytosis.
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27
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Tsai PSJ, Brewis IA, van Maaren J, Gadella BM. Involvement of complexin 2 in docking, locking and unlocking of different SNARE complexes during sperm capacitation and induced acrosomal exocytosis. PLoS One 2012; 7:e32603. [PMID: 22412896 PMCID: PMC3295773 DOI: 10.1371/journal.pone.0032603] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2011] [Accepted: 01/27/2012] [Indexed: 12/31/2022] Open
Abstract
Acrosomal exocytosis (AE) is an intracellular multipoint fusion reaction of the sperm plasma membrane (PM) with the outer acrosomal membrane (OAM). This unique exocytotic event enables the penetration of the sperm through the zona pellucida of the oocyte. We previously observed a stable docking of OAM to the PM brought about by the formation of the trans-SNARE complex (syntaxin 1B, SNAP 23 and VAMP 3). By using electron microscopy, immunochemistry and immunofluorescence techniques in combination with functional studies and proteomic approaches, we here demonstrate that calcium ionophore-induced AE results in the formation of unilamellar hybrid membrane vesicles containing a mixture of components originating from the two fused membranes. These mixed vesicles (MV) do not contain the earlier reported trimeric SNARE complex but instead possess a novel trimeric SNARE complex that contained syntaxin 3, SNAP 23 and VAMP 2, with an additional SNARE interacting protein, complexin 2. Our data indicate that the earlier reported raft and capacitation-dependent docking phenomenon between the PM and OAM allows a specific rearrangement of molecules between the two docked membranes and is involved in (1) recruiting SNAREs and complexin 2 in the newly formed lipid-ordered microdomains, (2) the assembly of a fusion-driving SNARE complex which executes Ca2+-dependent AE, (3) the disassembly of the earlier reported docking SNARE complex, (4) the recruitment of secondary zona binding proteins at the zona interacting sperm surface. The possibility to study separate and dynamic interactions between SNARE proteins, complexin and Ca2+ which are all involved in AE make sperm an ideal model for studying exocytosis.
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Affiliation(s)
- Pei-Shiue J. Tsai
- Department of Farm Animal Health, Graduate School of Animal Health, Faculty of Veterinary Medicine, Utrecht University, Utrecht, the Netherlands
- Department of Biochemistry and Cell Biology, Graduate School of Animal Health, Faculty of Veterinary Medicine, Utrecht University, Utrecht, the Netherlands
| | - Ian A. Brewis
- Cardiff University School of Medicine, Cardiff, United Kingdom
| | - Jillis van Maaren
- Department of Farm Animal Health, Graduate School of Animal Health, Faculty of Veterinary Medicine, Utrecht University, Utrecht, the Netherlands
| | - Bart M. Gadella
- Department of Farm Animal Health, Graduate School of Animal Health, Faculty of Veterinary Medicine, Utrecht University, Utrecht, the Netherlands
- Department of Biochemistry and Cell Biology, Graduate School of Animal Health, Faculty of Veterinary Medicine, Utrecht University, Utrecht, the Netherlands
- * E-mail:
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Lin L, Tran T, Hu S, Cramer T, Komuniecki R, Steven RM. RHGF-2 is an essential Rho-1 specific RhoGEF that binds to the multi-PDZ domain scaffold protein MPZ-1 in Caenorhabditis elegans. PLoS One 2012; 7:e31499. [PMID: 22363657 PMCID: PMC3282746 DOI: 10.1371/journal.pone.0031499] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2011] [Accepted: 01/12/2012] [Indexed: 11/18/2022] Open
Abstract
RhoGEF proteins activate the Rho family of small GTPases and thus play a key role in regulating fundamental cellular processes such as cell morphology and polarity, cell cycle progression and gene transcription. We identified a Caenorhabditis elegans RhoGEF protein, RHGF-2, as a binding partner of the C. elegans multi-PDZ domain scaffold protein MPZ-1 (MUPP1 in mammals). RHGF-2 exhibits significant identity to the mammalian RhoGEFs PLEKHG5/Tech/Syx and contains a class I C-terminal PDZ binding motif (SDV) that interacts most strongly to MPZ-1 PDZ domain eight. RHGF-2 RhoGEF activity is specific to the C. elegans RhoA homolog RHO-1 as determined by direct binding, GDP/GTP exchange and serum response element-driven reporter activity. rhgf-2 is an essential gene since rhgf-2 deletion mutants do not elongate during embryogenesis and hatch as short immobile animals that arrest development. Interestingly, the expression of a functional rhgf-2::gfp transgene appears to be exclusively neuronal and rhgf-2 overexpression results in loopy movement with exaggerated body bends. Transient expression of RHGF-2 in N1E-115 neuroblastoma cells prevents neurite outgrowth similar to constitutive RhoA activation in these cells. Together, these observations indicate neuronally expressed RHGF-2 is an essential RHO-1 specific RhoGEF that binds most strongly to MPZ-1 PDZ domain eight and is required for wild-type C. elegans morphology and growth.
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Affiliation(s)
- Li Lin
- Department of Biological Sciences, University of Toledo, Toledo, Ohio, United States of America
| | - Thuy Tran
- Department of Biological Sciences, University of Toledo, Toledo, Ohio, United States of America
| | - Shuang Hu
- Department of Biological Sciences, University of Toledo, Toledo, Ohio, United States of America
| | - Todd Cramer
- Department of Biological Sciences, University of Toledo, Toledo, Ohio, United States of America
| | - Richard Komuniecki
- Department of Biological Sciences, University of Toledo, Toledo, Ohio, United States of America
| | - Robert M. Steven
- Department of Biological Sciences, University of Toledo, Toledo, Ohio, United States of America
- * E-mail:
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Hornbruch-Freitag C, Griemert B, Buttgereit D, Renkawitz-Pohl R. Drosophila Swiprosin-1/EFHD2 accumulates at the prefusion complex stage during Drosophila myoblast fusion. J Cell Sci 2011; 124:3266-78. [PMID: 21896648 DOI: 10.1242/jcs.083907] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
In the Drosophila embryo, transient cell adhesion during myoblast fusion is known to lead to the formation of fusion-restricted myogenic-adhesive structures (FuRMASs). Here, we report that within these FuRMASs, a Drosophila homologue of human and mouse swiprosins (EF-hand-domain-containing proteins) is expressed, which we named Drosophila Swiprosin-1 (Drosophila Swip-1). Drosophila Swip-1 is highly conserved and is closely related to the calcium-binding proteins swiprosin-1 and swiprosin-2 that have a role in the immune system in humans and mice. Our study shows that Drosophila Swip-1 is also expressed in corresponding cells of the Drosophila immune system. During myoblast fusion, Drosophila Swip-1 accumulates transiently in the foci of fusion-competent myoblasts (FCMs). Both the EF-hand and the coiled-coil domain of Drosophila Swip-1 are required to localise the protein to these foci. The formation of Drosophila Swip-1 foci requires successful cell adhesion between FCMs and founder cells (FCs) or growing myotubes. Moreover, Drosophila Swip-1 foci were found to increase in number in sing(22) mutants, which arrest myoblast fusion after prefusion complex formation. By contrast, Drosophila Swip-1 foci are not significantly enriched in blow(2) and kette(J4-48) mutants, which stop myogenesis beyond the prefusion complex stage but before plasma membrane merging. Therefore, we hypothesise that Drosophila Swip-1 participates in the breakdown of the prefusion complex during the progression of myoblast fusion.
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Gadella BM, Evans JP. Membrane Fusions During Mammalian Fertilization. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2011; 713:65-80. [DOI: 10.1007/978-94-007-0763-4_5] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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Zitranski N, Borth H, Ackermann F, Meyer D, Vieweg L, Breit A, Gudermann T, Boekhoff I. The "acrosomal synapse": Subcellular organization by lipid rafts and scaffolding proteins exhibits high similarities in neurons and mammalian spermatozoa. Commun Integr Biol 2010; 3:513-21. [PMID: 21331227 DOI: 10.4161/cib.3.6.13137] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2010] [Revised: 07/23/2010] [Accepted: 07/23/2010] [Indexed: 12/18/2022] Open
Abstract
Mammalian spermatozoa are highly polarized cells composed of two morphological and functional units, each optimized for a special task. Although the apparent division into head and tail may as such represent the anatomical basis to avoid random diffusion of their special sets of signaling proteins and lipids, recent findings demonstrate the presence of lipid raft-derived membrane platforms and specific scaffolding proteins, thus indicating that smaller sub-domains exist in the two functional units of male germ cells. The aim of this review is to summarize new insights into the principles of subcellular organization in mammalian spermatozoa. Special emphasis is placed on recent observations indicating that an "acrosomal synapse" is formed by lipid raft-derived membrane micro-environments and multidomain scaffolding proteins. Both mechanisms appear to be responsible for ensuring the attachment of the huge acrosomal vesicle to the overlaying plasma membrane, as well as for preventing an accidental spontaneous loss of the single acrosome.
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Affiliation(s)
- Nele Zitranski
- Walther-Straub-Institute of Pharmacology and Toxicology; Ludwig-Maximilians-University; Munich, Germany
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Tsai PS, Garcia-Gil N, van Haeften T, Gadella BM. How pig sperm prepares to fertilize: stable acrosome docking to the plasma membrane. PLoS One 2010; 5:e11204. [PMID: 20585455 PMCID: PMC2887851 DOI: 10.1371/journal.pone.0011204] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2009] [Accepted: 05/26/2010] [Indexed: 11/19/2022] Open
Abstract
Background Mammalian sperms are activated in the oviduct. This process, which involves extensive sperm surface remodelling, is required for fertilization and can be mimicked under in vitro fertilization conditions (IVF). Methodology/Principal Findings Here we demonstrate that such treatments caused stable docking and priming of the acrosome membrane to the apical sperm head surface without the emergence of exocytotic membrane fusion. The interacting membranes could be isolated as bilamellar membrane structures after cell disruption. These membrane structures as well as whole capacitated sperm contained stable ternary trans-SNARE complexes that were composed of VAMP 3 and syntaxin 1B from the plasma membrane and SNAP 23 from the acrosomal membrane. This trans-SNARE complex was not observed in control sperm. Conclusions/Significance We propose that this capacitation driven membrane docking and stability thereof is a preparative step prior to the multipoint membrane fusions characteristic for the acrosome reaction induced by sperm-zona binding. Thus, sperm can be considered a valuable model for studying exocytosis.
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Affiliation(s)
- Pei-Shiue Tsai
- Department of Biochemistry and Cell Biology, Graduate School of Animal Health, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
- Department of Farm Animal Health, Graduate School of Animal Health, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - Núria Garcia-Gil
- Department of Biochemistry and Cell Biology, Graduate School of Animal Health, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - Theo van Haeften
- Department of Biochemistry and Cell Biology, Graduate School of Animal Health, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - Bart M. Gadella
- Department of Biochemistry and Cell Biology, Graduate School of Animal Health, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
- Department of Farm Animal Health, Graduate School of Animal Health, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
- * E-mail:
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Castillo Bennett J, Roggero CM, Mancifesta FE, Mayorga LS. Calcineurin-mediated dephosphorylation of synaptotagmin VI is necessary for acrosomal exocytosis. J Biol Chem 2010; 285:26269-78. [PMID: 20551332 DOI: 10.1074/jbc.m109.095752] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Regulated secretion is a fundamental process underlying the function of many cell types. In particular, acrosomal exocytosis in mammalian sperm is essential for egg fertilization. In general, exocytosis is initiated by a cytosolic calcium increase. In this report we show that calcium affects several factors during human sperm acrosomal exocytosis. By using an antibody that specifically recognizes synaptotagmin VI phosphorylated at the polybasic region of the C2B domain, we showed that a calcium-dependent dephosphorylation of this protein occurred at early stages of the acrosomal exocytosis in streptolysin O-permeabilized sperm. We identified the phosphatase as calcineurin and showed that the activity of this enzyme is absolutely required during the early steps of the secretory process. When added to sperm, an inhibitor-insensitive, catalytically active domain of calcineurin was able to rescue the effect of the specific calcineurin inhibitor cyclosporin A. This same domain dephosphorylated recombinant synaptotagmin VI C2B domain, validating this protein as a new substrate for calcineurin. When sperm were treated with catalytically active calcineurin before stimulation, exocytosis was inhibited, an effect that was rescued by the phosphomimetic synaptotagmin VI C2B-T418E,T419E mutant domain. These observations indicate that synaptotagmin must be dephosphorylated at a specific window of time and suggest that phosphorylated synaptotagmin has an active role at early stages of the acrosomal exocytosis.
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Affiliation(s)
- Jimena Castillo Bennett
- Instituto de Histología y Embriología, Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Ciencias Médicas, Universidad Nacional de Cuyo, Mendoza 5500, Argentina
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