1
|
Klinsky OG, Wetten PA, Zanni-Ruiz E, Pavarotti MA, Berberian MV, Michaut MA. The light chain of tetanus toxin bound to arginine-rich cell-penetrating peptide inhibits cortical reaction in mouse oocytes. Front Cell Dev Biol 2023; 11:1259421. [PMID: 38033867 PMCID: PMC10684777 DOI: 10.3389/fcell.2023.1259421] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2023] [Accepted: 10/30/2023] [Indexed: 12/02/2023] Open
Abstract
Introduction: Cortical reaction is a secretory process that occurs after a spermatozoon fuses with the oocyte, avoiding the fusion of additional sperm. During this exocytic event, the cortical granule membrane fuses with the oocyte plasma membrane. We have identified several molecular components involved in this process and confirmed that SNARE proteins regulate membrane fusion during cortical reaction in mouse oocytes. In those studies, we microinjected different nonpermeable reagents to demonstrate the participation of a specific protein in the cortical reaction. However, the microinjection technique has several limitations. In this work, we aimed to assess the potential of cell-penetrating peptides (CPP) as biotechnological tools for delivering molecules into oocytes, and to evaluate the functionality of the permeable tetanus toxin (bound to CPP sequence) during cortical reaction. Methods: Arginine-rich cell-penetrating peptides have demonstrated the optimal internalization of small molecules in mammalian cells. Two arginine-rich CPP were used in the present study. One, labeled with 5-carboxyfluorescein, to characterize the factors that can modulate its internalization, and the other, the permeable light chain of tetanus toxin, that cleaves the SNAREs VAMP1 and VAMP3 expressed in mouse oocytes. Results: Results showed that fluorescent CPP was internalized into the oocyte cytoplasm and that internalization was dependent on the concentration, time, temperature, and maturation stage of the oocyte. Using our functional assay to study cortical reaction, the light chain of tetanus toxin bound to arginine-rich cell-penetrating peptide inhibited cortical granules exocytosis. Discussion: Results obtained from the use of permeable peptides demonstrate that this CPP is a promising biotechnological tool to study functional macromolecules in mouse oocytes.
Collapse
Affiliation(s)
- Omar G. Klinsky
- Laboratorio de Biología Reproductiva y Molecular, Instituto de Histología y Embriología de Mendoza (IHEM), Universidad Nacional de Cuyo-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Mendoza, Argentina
- Facultad de Ciencias Médicas, Universidad Nacional de Cuyo, Mendoza, Argentina
| | - Paula A. Wetten
- Laboratorio de Biología Reproductiva y Molecular, Instituto de Histología y Embriología de Mendoza (IHEM), Universidad Nacional de Cuyo-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Mendoza, Argentina
- Facultad de Ciencias Médicas, Universidad Nacional de Cuyo, Mendoza, Argentina
| | - Emilia Zanni-Ruiz
- Laboratorio de Transporte Intracelular, Instituto de Histología and Embriología de Mendoza (IHEM), Universidad Nacional de Cuyo-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Mendoza, Argentina
| | - Martín A. Pavarotti
- Laboratorio de Transporte Intracelular, Instituto de Histología and Embriología de Mendoza (IHEM), Universidad Nacional de Cuyo-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Mendoza, Argentina
| | - María Victoria Berberian
- Laboratorio de Transporte Intracelular, Instituto de Histología and Embriología de Mendoza (IHEM), Universidad Nacional de Cuyo-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Mendoza, Argentina
- Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Cuyo, Mendoza, Argentina
- Instituto Interdisciplinario de Ciencias Básicas, Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Cuyo, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Mendoza, Argentina
| | - Marcela A. Michaut
- Laboratorio de Biología Reproductiva y Molecular, Instituto de Histología y Embriología de Mendoza (IHEM), Universidad Nacional de Cuyo-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Mendoza, Argentina
- Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Cuyo, Mendoza, Argentina
| |
Collapse
|
2
|
Michaut MA, Souza-Fabjan JMG, Fissore RA. Editorial: The Fertilization Success From the Oocyte's Perspective. Front Cell Dev Biol 2021; 9:810420. [PMID: 34957125 PMCID: PMC8695974 DOI: 10.3389/fcell.2021.810420] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2021] [Accepted: 11/10/2021] [Indexed: 11/24/2022] Open
Affiliation(s)
- Marcela A Michaut
- Instituto de Histología y Embriología (IHEM), Universidad Nacional de Cuyo, CONICET; Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Cuyo, Mendoza, Argentina
| | | | - Rafael A Fissore
- Department of Veterinary and Animal Sciences, University of Massachusetts, Amherst, Amherst, United States
| |
Collapse
|
3
|
Arcos A, de Paola M, Gianetti D, Acuña D, Velásquez ZD, Miró MP, Toro G, Hinrichsen B, Muñoz RI, Lin Y, Mardones GA, Ehrenfeld P, Rivera FJ, Michaut MA, Batiz LF. Publisher Correction: α-SNAP is expressed in mouse ovarian granulosa cells and plays a key role in folliculogenesis and female fertility. Sci Rep 2020; 10:5691. [PMID: 32214131 PMCID: PMC7096406 DOI: 10.1038/s41598-020-61863-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Affiliation(s)
- Alexis Arcos
- Instituto de Anatomía, Histología y Patología, Facultad de Medicina, Universidad Austral de Chile, Valdivia, Chile
| | - Matilde de Paola
- Instituto de Histología y Embriología (IHEM), Universidad Nacional de Cuyo-CONICET, Mendoza, Argentina
| | - Diego Gianetti
- Instituto de Anatomía, Histología y Patología, Facultad de Medicina, Universidad Austral de Chile, Valdivia, Chile
| | - Diego Acuña
- Instituto de Anatomía, Histología y Patología, Facultad de Medicina, Universidad Austral de Chile, Valdivia, Chile
| | - Zahady D Velásquez
- Instituto de Anatomía, Histología y Patología, Facultad de Medicina, Universidad Austral de Chile, Valdivia, Chile
| | - María Paz Miró
- Instituto de Anatomía, Histología y Patología, Facultad de Medicina, Universidad Austral de Chile, Valdivia, Chile
| | - Gabriela Toro
- Instituto de Anatomía, Histología y Patología, Facultad de Medicina, Universidad Austral de Chile, Valdivia, Chile
| | - Bryan Hinrichsen
- Instituto de Anatomía, Histología y Patología, Facultad de Medicina, Universidad Austral de Chile, Valdivia, Chile
| | - Rosa Iris Muñoz
- Instituto de Anatomía, Histología y Patología, Facultad de Medicina, Universidad Austral de Chile, Valdivia, Chile
| | - Yimo Lin
- Instituto de Fisiología, Facultad de Medicina, Universidad Austral de Chile, Valdivia, Chile.,Department of Neurosurgery, Oregon Health and Science University, Portland, Oregon, USA
| | - Gonzalo A Mardones
- Instituto de Fisiología, Facultad de Medicina, Universidad Austral de Chile, Valdivia, Chile.,Center for Interdisciplinary Studies on the Nervous System (CISNe), Universidad Austral de Chile, Valdivia, Chile
| | - Pamela Ehrenfeld
- Instituto de Anatomía, Histología y Patología, Facultad de Medicina, Universidad Austral de Chile, Valdivia, Chile.,Center for Interdisciplinary Studies on the Nervous System (CISNe), Universidad Austral de Chile, Valdivia, Chile
| | - Francisco J Rivera
- Instituto de Anatomía, Histología y Patología, Facultad de Medicina, Universidad Austral de Chile, Valdivia, Chile.,Center for Interdisciplinary Studies on the Nervous System (CISNe), Universidad Austral de Chile, Valdivia, Chile.,Institute of Molecular Regenerative Medicine, Paracelsus Medical University Salzburg, Salzburg, A-5020, Austria.,Spinal Cord Injury and Tissue Regeneration Center Salzburg, Paracelsus Medical University Salzburg, Salzburg, A-5020, Austria
| | - Marcela A Michaut
- Instituto de Histología y Embriología (IHEM), Universidad Nacional de Cuyo-CONICET, Mendoza, Argentina. .,Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Cuyo, Mendoza, Argentina.
| | - Luis Federico Batiz
- Instituto de Anatomía, Histología y Patología, Facultad de Medicina, Universidad Austral de Chile, Valdivia, Chile. .,Center for Interdisciplinary Studies on the Nervous System (CISNe), Universidad Austral de Chile, Valdivia, Chile. .,Centro de Investigación Biomédica (CIB), Facultad de Medicina, Universidad de los Andes, Santiago, Chile.
| |
Collapse
|
4
|
Cappa AI, de Paola M, Wetten P, De Blas GA, Michaut MA. Live imaging of cortical granule exocytosis reveals that in vitro matured mouse oocytes are not fully competent to secrete their content. Biol Open 2018; 7:bio031872. [PMID: 30341105 PMCID: PMC6310882 DOI: 10.1242/bio.031872] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2017] [Accepted: 10/10/2018] [Indexed: 12/30/2022] Open
Abstract
Oocyte in vitro maturation does not entirely support all the nuclear and cytoplasmic changes that occur physiologically, and it is poorly understood whether in vitro maturation affects the competence of cortical granules to secrete their content during cortical reaction. Here, we characterize cortical granule exocytosis (CGE) in live mouse oocytes activated by strontium chloride using the fluorescent lectin FITC-LCA. We compared the kinetic of CGE between ovulated (in vivo matured, IVO) and in vitro matured (IVM) mouse oocytes. Results show that: (1) IVM oocytes have a severely reduced response to strontium chloride; (2) the low response was confirmed by quantification of remnant cortical granules in permeabilized cells and by a novel method to quantify the exudate in non-permeabilized cells; (3) the kinetic of CGE in IVO oocytes was rapid and synchronous; (4) the kinetic of CGE in IVM oocytes was delayed and asynchronous; (5) cortical granules in IVM oocytes show an irregular limit in regards to the cortical granule free domain. We propose the analysis of CGE in live oocytes as a biological test to evaluate the competence of IVM mouse oocytes.This article has an associated First Person interview with the first author of the paper.
Collapse
Affiliation(s)
- Andrea I Cappa
- Laboratorio de Biología Reproductiva y Molecular, Instituto de Histología y Embriología, Universidad Nacional de Cuyo-CONICET, Av. Libertador 80, 5500, Mendoza, Argentina
| | - Matilde de Paola
- Laboratorio de Biología Reproductiva y Molecular, Instituto de Histología y Embriología, Universidad Nacional de Cuyo-CONICET, Av. Libertador 80, 5500, Mendoza, Argentina
| | - Paula Wetten
- Laboratorio de Biología Reproductiva y Molecular, Instituto de Histología y Embriología, Universidad Nacional de Cuyo-CONICET, Av. Libertador 80, 5500, Mendoza, Argentina
| | - Gerardo A De Blas
- Laboratorio de Biología Reproductiva y Molecular, Instituto de Histología y Embriología, Universidad Nacional de Cuyo-CONICET, Av. Libertador 80, 5500, Mendoza, Argentina
- Universidad Nacional de Cuyo, Facultad de Ciencias Médicas, Área de Farmacología, Av. Libertador 80, 5500, Mendoza, Argentina
| | - Marcela A Michaut
- Laboratorio de Biología Reproductiva y Molecular, Instituto de Histología y Embriología, Universidad Nacional de Cuyo-CONICET, Av. Libertador 80, 5500, Mendoza, Argentina
- Universidad Nacional de Cuyo, Facultad de Ciencias Exactas y Naturales, Departamento de Biología, Padre Jorge Contreras 1300, 5500, Mendoza, Argentina
| |
Collapse
|
5
|
Arcos A, de Paola M, Gianetti D, Acuña D, Velásquez ZD, Miró MP, Toro G, Hinrichsen B, Muñoz RI, Lin Y, Mardones GA, Ehrenfeld P, Rivera FJ, Michaut MA, Batiz LF. α-SNAP is expressed in mouse ovarian granulosa cells and plays a key role in folliculogenesis and female fertility. Sci Rep 2017; 7:11765. [PMID: 28924180 PMCID: PMC5603506 DOI: 10.1038/s41598-017-12292-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Accepted: 09/05/2017] [Indexed: 01/13/2023] Open
Abstract
The balance between ovarian folliculogenesis and follicular atresia is critical for female fertility and is strictly regulated by a complex network of neuroendocrine and intra-ovarian signals. Despite the numerous functions executed by granulosa cells (GCs) in ovarian physiology, the role of multifunctional proteins able to simultaneously coordinate/modulate several cellular pathways is unclear. Soluble N-ethylmaleimide-sensitive factor (NSF) attachment protein (α-SNAP) is a multifunctional protein that participates in SNARE-mediated membrane fusion events. In addition, it regulates cell-to-cell adhesion, AMPK signaling, autophagy and apoptosis in different cell types. In this study we examined the expression pattern of α-SNAP in ovarian tissue and the consequences of α-SNAP (M105I) mutation (hyh mutation) in folliculogenesis and female fertility. Our results showed that α-SNAP protein is highly expressed in GCs and its expression is modulated by gonadotropin stimuli. On the other hand, α-SNAP-mutant mice show a reduction in α-SNAP protein levels. Moreover, increased apoptosis of GCs and follicular atresia, reduced ovulation rate, and a dramatic decline in fertility is observed in α-SNAP-mutant females. In conclusion, α-SNAP plays a critical role in the balance between follicular development and atresia. Consequently, a reduction in its expression/function (M105I mutation) causes early depletion of ovarian follicles and female subfertility.
Collapse
Affiliation(s)
- Alexis Arcos
- Instituto de Anatomía, Histología y Patología, Facultad de Medicina, Universidad Austral de Chile, Valdivia, Chile
| | - Matilde de Paola
- Instituto de Histología y Embriología (IHEM), Universidad Nacional de Cuyo-CONICET, Mendoza, Argentina
| | - Diego Gianetti
- Instituto de Anatomía, Histología y Patología, Facultad de Medicina, Universidad Austral de Chile, Valdivia, Chile
| | - Diego Acuña
- Instituto de Anatomía, Histología y Patología, Facultad de Medicina, Universidad Austral de Chile, Valdivia, Chile
| | - Zahady D Velásquez
- Instituto de Anatomía, Histología y Patología, Facultad de Medicina, Universidad Austral de Chile, Valdivia, Chile
| | - María Paz Miró
- Instituto de Anatomía, Histología y Patología, Facultad de Medicina, Universidad Austral de Chile, Valdivia, Chile
| | - Gabriela Toro
- Instituto de Anatomía, Histología y Patología, Facultad de Medicina, Universidad Austral de Chile, Valdivia, Chile
| | - Bryan Hinrichsen
- Instituto de Anatomía, Histología y Patología, Facultad de Medicina, Universidad Austral de Chile, Valdivia, Chile
| | - Rosa Iris Muñoz
- Instituto de Anatomía, Histología y Patología, Facultad de Medicina, Universidad Austral de Chile, Valdivia, Chile
| | - Yimo Lin
- Instituto de Fisiología, Facultad de Medicina, Universidad Austral de Chile, Valdivia, Chile.,Department of Neurosurgery, Oregon Health and Science University, Portland, Oregon, USA
| | - Gonzalo A Mardones
- Instituto de Fisiología, Facultad de Medicina, Universidad Austral de Chile, Valdivia, Chile.,Center for Interdisciplinary Studies on the Nervous System (CISNe), Universidad Austral de Chile, Valdivia, Chile
| | - Pamela Ehrenfeld
- Instituto de Anatomía, Histología y Patología, Facultad de Medicina, Universidad Austral de Chile, Valdivia, Chile.,Center for Interdisciplinary Studies on the Nervous System (CISNe), Universidad Austral de Chile, Valdivia, Chile
| | - Francisco J Rivera
- Instituto de Anatomía, Histología y Patología, Facultad de Medicina, Universidad Austral de Chile, Valdivia, Chile.,Center for Interdisciplinary Studies on the Nervous System (CISNe), Universidad Austral de Chile, Valdivia, Chile.,Institute of Molecular Regenerative Medicine, Paracelsus Medical University Salzburg, Salzburg, A-5020, Austria.,Spinal Cord Injury and Tissue Regeneration Center Salzburg, Paracelsus Medical University Salzburg, Salzburg, A-5020, Austria
| | - Marcela A Michaut
- Instituto de Histología y Embriología (IHEM), Universidad Nacional de Cuyo-CONICET, Mendoza, Argentina. .,Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Cuyo, Mendoza, Argentina.
| | - Luis Federico Batiz
- Instituto de Anatomía, Histología y Patología, Facultad de Medicina, Universidad Austral de Chile, Valdivia, Chile. .,Center for Interdisciplinary Studies on the Nervous System (CISNe), Universidad Austral de Chile, Valdivia, Chile. .,Centro de Investigación Biomédica (CIB), Facultad de Medicina, Universidad de los Andes, Santiago, Chile.
| |
Collapse
|
6
|
Bello OD, Cappa AI, de Paola M, Zanetti MN, Fukuda M, Fissore RA, Mayorga LS, Michaut MA. Rab3A, a possible marker of cortical granules, participates in cortical granule exocytosis in mouse eggs. Exp Cell Res 2016; 347:42-51. [PMID: 27423421 DOI: 10.1016/j.yexcr.2016.07.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Revised: 07/04/2016] [Accepted: 07/12/2016] [Indexed: 10/21/2022]
Abstract
Fusion of cortical granules with the oocyte plasma membrane is the most significant event to prevent polyspermy. This particular exocytosis, also known as cortical reaction, is regulated by calcium and its molecular mechanism is still not known. Rab3A, a member of the small GTP-binding protein superfamily, has been implicated in calcium-dependent exocytosis and is not yet clear whether Rab3A participates in cortical granules exocytosis. Here, we examine the involvement of Rab3A in the physiology of cortical granules, particularly, in their distribution during oocyte maturation and activation, and their participation in membrane fusion during cortical granule exocytosis. Immunofluorescence and Western blot analysis showed that Rab3A and cortical granules have a similar migration pattern during oocyte maturation, and that Rab3A is no longer detected after cortical granule exocytosis. These results suggested that Rab3A might be a marker of cortical granules. Overexpression of EGFP-Rab3A colocalized with cortical granules with a Pearson correlation coefficient of +0.967, indicating that Rab3A and cortical granules have almost a perfect colocalization in the egg cortical region. Using a functional assay, we demonstrated that microinjection of recombinant, prenylated and active GST-Rab3A triggered cortical granule exocytosis, indicating that Rab3A has an active role in this secretory pathway. To confirm this active role, we inhibited the function of endogenous Rab3A by microinjecting a polyclonal antibody raised against Rab3A prior to parthenogenetic activation. Our results showed that Rab3A antibody microinjection abolished cortical granule exocytosis in parthenogenetically activated oocytes. Altogether, our findings confirm that Rab3A might function as a marker of cortical granules and participates in cortical granule exocytosis in mouse eggs.
Collapse
Affiliation(s)
- Oscar Daniel Bello
- Instituto de Histología y Embriología, CONICET - Universidad Nacional de Cuyo, Av. Libertador 80, 5500 Mendoza, Argentina
| | - Andrea Isabel Cappa
- Instituto de Histología y Embriología, CONICET - Universidad Nacional de Cuyo, Av. Libertador 80, 5500 Mendoza, Argentina
| | - Matilde de Paola
- Instituto de Histología y Embriología, CONICET - Universidad Nacional de Cuyo, Av. Libertador 80, 5500 Mendoza, Argentina
| | - María Natalia Zanetti
- Instituto de Histología y Embriología, CONICET - Universidad Nacional de Cuyo, Av. Libertador 80, 5500 Mendoza, Argentina
| | - Mitsunori Fukuda
- Department of Developmental Biology and Neurosciences, Graduate School of Life Sciences, Tohoku University, Sendai, Miyagi 980-8578, Japan
| | - Rafael A Fissore
- Department of Veterinary and Animal Sciences, University of Massachusetts Amherst, 661 North Pleasant Street, Amherst, MA 01003, USA
| | - Luis S Mayorga
- Instituto de Histología y Embriología, CONICET - Universidad Nacional de Cuyo, Av. Libertador 80, 5500 Mendoza, Argentina
| | - Marcela A Michaut
- Instituto de Histología y Embriología, CONICET - Universidad Nacional de Cuyo, Av. Libertador 80, 5500 Mendoza, Argentina; Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Cuyo, Argentina.
| |
Collapse
|
7
|
Bello OD, Zanetti MN, Mayorga LS, Michaut MA. RIM, Munc13, and Rab3A interplay in acrosomal exocytosis. Exp Cell Res 2012; 318:478-88. [PMID: 22248876 DOI: 10.1016/j.yexcr.2012.01.002] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2011] [Revised: 12/09/2011] [Accepted: 01/03/2012] [Indexed: 12/26/2022]
Abstract
Exocytosis is a highly regulated, multistage process consisting of multiple functionally definable stages, including recruitment, targeting, tethering, priming, and docking of secretory vesicles with the plasma membrane, followed by calcium-triggered membrane fusion. The acrosome reaction of spermatozoa is a complex, calcium-dependent regulated exocytosis. Fusion at multiple sites between the outer acrosomal membrane and the cell membrane causes the release of the acrosomal contents and the loss of the membranes surrounding the acrosome. Not much is known about the molecules that mediate membrane docking in this particular fusion model. In neurons, the formation of the ternary RIM/Munc13/Rab3A complex has been suggested as a critical component of synaptic vesicles docking. Previously, we demonstrated that Rab3A localizes to the acrosomal region in human sperm, stimulates acrosomal exocytosis, and participates in an early stage during membrane fusion. Here, we report that RIM and Munc13 are also present in human sperm and localize to the acrosomal region. Like Rab3A, RIM and Munc13 participate in a prefusion step before the efflux of intra-acrosomal calcium. By means of a functional assay using antibodies and recombinant proteins, we show that RIM, Munc13 and Rab3A interplay during acrosomal exocytosis. Finally, we report by electron transmission microscopy that sequestering RIM and Rab3A alters the docking of the acrosomal membrane to the plasma membrane during calcium-activated acrosomal exocytosis. Our results suggest that the RIM/Munc13/Rab3 A complex participates in acrosomal exocytosis and that RIM and Rab3A have central roles in membrane docking.
Collapse
Affiliation(s)
- Oscar D Bello
- Laboratorio de Biología Celular y Molecular, Instituto de Histología y Embriología, IHEM (CONICET-UNCuyo), Facultad de Ciencias Médicas, Argentina
| | | | | | | |
Collapse
|
8
|
Schlingmann K, Michaut MA, McElwee JL, Wolff CA, Travis AJ, Turner RM. Calmodulin and CaMKII in the Sperm Principal Piece: Evidence for a Motility-Related Calcium/Calmodulin Pathway. ACTA ACUST UNITED AC 2007; 28:706-16. [PMID: 17460096 DOI: 10.2164/jandrol.106.001669] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Both cyclic AMP (cAMP)/protein kinase A (PKA) and calcium (Ca(2+)) signaling pathways are known to be involved in the regulation of motility in mammalian sperm. Calmodulin (CaM) is a ubiquitous Ca(2+) sensor that has been implicated in the acrosome reaction. In this report, we identify an insoluble pool of CaM in sperm and show that the protein, in addition to its presence in the acrosome, is found in the principal piece of the flagellum. These findings are consistent with, though not proof of, the presence of a pool of CaM in the fibrous sheath. The Ca(2+)/CaM-dependent protein kinase IIbeta (CaMKIIbeta), which is a downstream target of Ca(2+)/CaM, similarly localizes to the principal piece. In addition, we confirm earlier reports that a CaM inhibitor decreases sperm motility. However, we find that this inhibition can be largely reversed by stimulation of PKA if substrates for oxidative respiration are present in the medium. Our results suggest that the Ca(2+)/CaM/CaMKII signaling pathway in the sperm principal piece is involved in regulating sperm motility, and that this pathway functions either in parallel with or upstream of the cAMP/PKA pathway.
Collapse
Affiliation(s)
- Karen Schlingmann
- New Bolton Center, University of Pennsylvania School of Veterinary Medicine, 382 West Street Rd, Kennett Square, PA 19348, USA
| | | | | | | | | | | |
Collapse
|
9
|
Roggero CM, Tomes CN, De Blas GA, Castillo J, Michaut MA, Fukuda M, Mayorga LS. Protein kinase C-mediated phosphorylation of the two polybasic regions of synaptotagmin VI regulates their function in acrosomal exocytosis. Dev Biol 2006; 285:422-35. [PMID: 16111671 DOI: 10.1016/j.ydbio.2005.07.007] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2005] [Revised: 07/09/2005] [Accepted: 07/11/2005] [Indexed: 11/22/2022]
Abstract
We have previously reported that synaptotagmin VI is present in human sperm cells and that a recombinant protein containing the C2A and C2B domains abrogates acrosomal exocytosis in permeabilized spermatozoa, an effect that was regulated by phosphorylation. In this report, we show that each individual C2 domain blocks acrosomal exocytosis. The inhibitory effect was completely abrogated by phosphorylation of the domains with purified PKCbetaII. We found by site-directed mutagenesis that Thr418 and/or Thr419 in the polybasic region (KKKTTIK) of the C2B domain--a key region for the function of synaptotagmins--are the PKC target that regulates its inhibitory effect on acrosomal exocytosis. Similarly, we showed that Thr284 in the polybasic region of C2A (KCKLQTR) is the target for PKC-mediated phosphorylation in this domain. An antibody that specifically binds to the phosphorylated polybasic region of the C2B domain recognized endogenous phosphorylated synaptotagmin in the sperm acrosomal region. The antibody was inhibitory only at early stages of exocytosis in sperm acrosome reaction assays, and the immunolabeling decreased upon sperm stimulation, indicating that the protein is dephosphorylated during acrosomal exocytosis. Our results indicate that acrosomal exocytosis is regulated through the PKC-mediated phosphorylation of conserved threonines in the polybasic regions of synaptotagmin VI.
Collapse
Affiliation(s)
- Carlos M Roggero
- Laboratorio de Biología Celular y Molecular, Instituto de Histología y Embriología (IHEM-CONICET), Facultad de Ciencias Médicas, Universidad Nacional de Cuyo, Casilla de Correo 56, 5500 Mendoza, Argentina
| | | | | | | | | | | | | |
Collapse
|
10
|
Michaut MA, Williams CJ, Schultz RM. Phosphorylated MARCKS: A novel centrosome component that also defines a peripheral subdomain of the cortical actin cap in mouse eggs. Dev Biol 2005; 280:26-37. [PMID: 15766745 DOI: 10.1016/j.ydbio.2005.01.006] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2004] [Revised: 12/23/2004] [Accepted: 01/04/2005] [Indexed: 01/13/2023]
Abstract
MARCKS (myristoylated alanine-rich C-kinase substrate) is a major substrate for protein kinase C (PKC), a kinase that has multiple functions during oocyte maturation and egg activation, for example, spindle function and cytoskeleton reorganization. We examined temporal and spatial changes in p-MARCKS localization during maturation of mouse oocytes and found that p-MARCKS is a novel centrosome component based its co-localization with pericentrin and gamma-tubulin within microtubule organizing centers (MTOCs). Like pericentrin, p-MARCKS staining at the MI spindle poles was asymmetric. Based on this asymmetry, we found that one end of the spindle was preferentially extruded with the first polar body. At MII, however, the spindle poles had symmetrical p-MARCKS staining. p-MARCKS also was enriched in the periphery of the actin cap overlying the MI or MII spindle to form a ring-shaped subdomain. Because phosphorylation of MARCKS modulates its actin crosslinking function, this localization suggests p-MARCKS functions as part of the contractile apparatus during polar body emission. Our finding that an activator of conventional and novel PKC isoforms did not increase the amount of p-MARCKS suggested that an atypical isoform was responsible for MARCKS phosphorylation. Consistent with this idea, immunostaining revealed that the staining patterns of p-MARCKS and the active form of the atypical PKC zeta/lambda isoform(s) were very similar. These results show that p-MARCKS is a novel centrosome component and also defines a previously unrecognized subdomain of the actin cap overlying the spindle.
Collapse
Affiliation(s)
- Marcela A Michaut
- Center for Research on Reproduction and Women's Health and Department of Obstetrics and Gynecology, Philadelphia, PA 19104, USA
| | | | | |
Collapse
|
11
|
Tomes CN, De Blas GA, Michaut MA, Farré EV, Cherhitin O, Visconti PE, Mayorga LS. alpha-SNAP and NSF are required in a priming step during the human sperm acrosome reaction. Mol Hum Reprod 2004; 11:43-51. [PMID: 15542541 DOI: 10.1093/molehr/gah126] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The acrosome is a membrane-limited granule that overlies the nucleus of the mature spermatozoon. In response to physiological or pharmacological stimuli it undergoes a special type of Ca2+-dependent exocytosis termed the acrosome reaction (AR), which is an absolute prerequisite for fertilization. Aided by a streptolysin-O permeabilization protocol developed in our laboratory, we have previously demonstrated requirements for Rab3A, N-ethylmaleimide-sensitive factor (NSF), several soluble NSF-attachment protein receptor (SNARE) proteins, and synaptotagmin VI in the human sperm AR. Here, we show that alpha-soluble NSF-attachment protein (alpha-SNAP), a protein essential for most fusion events through its interaction with NSF and the SNARE complex, exhibits a direct role in the AR. First, the presence of alpha-SNAP is demonstrated by the Western blot of human sperm protein extracts. Immunostaining experiments reveal an acrosomal localization for this protein. Second, the Ca2+ and Rab3A-triggered ARs are inhibited by anti-alpha-SNAP antibodies. Third, bacterially expressed alpha-SNAP abolishes exocytosis in a fashion that depends on its interaction with NSF. Fourth, we show a requirement for alpha-SNAP/NSF in a prefusion step early in the exocytotic pathway, after the tethering of the acrosome to the plasma membrane and before the efflux of intra-acrosomal Ca2+. These results suggest a key role for alpha-SNAP/NSF in the AR, and strengthen our understanding of the molecular players involved in the vesicle-to-plasma membrane fusion taking place during exocytosis.
Collapse
Affiliation(s)
- C N Tomes
- Laboratorio de Biología Celular y Molecular, Instituto de Histología y Embriología (IHEM-CONICET), Facultad de Ciencias Médicas, CC 56, Universidad Nacional de Cuyo, 5500 Mendoza, Argentina.
| | | | | | | | | | | | | |
Collapse
|
12
|
Affiliation(s)
- M A Michaut
- Facultad de Química, Bioquímica y Farmacia, Universidad Nacional de San Luis, Argentina
| | | | | |
Collapse
|