Zinc Exocytosis is Sensitive to Myosin Light Chain Kinase Inhibition in Mouse and Human Eggs

Overview

Journal Mol Hum Reprod

Specialties Molecular Biology
Reproductive Medicine

Date 2020 Mar 3

PMID 32119740

Citations 6

Authors

Hoi Chang Lee

Maxwell E Edmonds

Francesca E Duncan

Thomas V OHalloran

Teresa K Woodruff

Affiliations

Soon will be listed here.

Abstract

Zinc dynamics are essential for oocyte meiotic maturation, egg activation, and preimplantation embryo development. During fertilisation and egg activation, the egg releases billions of zinc atoms (Zn2+) in an exocytotic event termed the 'zinc spark'. We hypothesised that this zinc transport and exocytosis is dependent upon the intracellular trafficking of cortical granules (CG) which requires myosin-actin-dependent motors. Treatment of mature mouse and human eggs with ML-7, a myosin light chain kinase inhibitor (MLCK), resulted in an 80% reduction in zinc spark intensity compared to untreated controls when activated with ionomycin. Moreover, CG migration towards the plasma membrane was significantly decreased in ML-7-treated eggs compared with controls when activated parthenogenetically with ionomycin. In sperm-induced fertilisation via intracytoplasmic sperm injection (ICSI), ML-7-treated mouse eggs exhibited decreased labile zinc intensity and cortical CG staining. Collectively, these data demonstrate that ML-7 treatment impairs zinc release from both murine and human eggs after activation, demonstrating that zinc exocytosis requires myosin light chain kinase activity. Further, these results provide additional support that zinc is likely stored and released from CGs. These data underscore the importance of intracellular zinc trafficking as a crucial component of egg maturation necessary for egg activation and early embryo development.

Citing Articles

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References

Hachem A, Godwin J, Ruas M, Lee H, Ferrer Buitrago M, Ardestani G . PLCζ is the physiological trigger of the Ca oscillations that induce embryogenesis in mammals but conception can occur in its absence. Development. 2017; 144(16):2914-2924. PMC: 5592814. DOI: 10.1242/dev.150227. View

Austin C, BRADEN A . An investigation of polyspermy in the rat and rabbit. Aust J Biol Sci. 1953; 6(4):674-92. View

Kim A, Bernhardt M, Kong B, Ahn R, Vogt S, Woodruff T . Zinc sparks are triggered by fertilization and facilitate cell cycle resumption in mammalian eggs. ACS Chem Biol. 2011; 6(7):716-23. PMC: 3171139. DOI: 10.1021/cb200084y. View

Tokuhiro K, Dean J . Glycan-Independent Gamete Recognition Triggers Egg Zinc Sparks and ZP2 Cleavage to Prevent Polyspermy. Dev Cell. 2018; 46(5):627-640.e5. PMC: 6549238. DOI: 10.1016/j.devcel.2018.07.020. View

Kim A, Vogt S, OHalloran T, Woodruff T . Zinc availability regulates exit from meiosis in maturing mammalian oocytes. Nat Chem Biol. 2010; 6(9):674-81. PMC: 2924620. DOI: 10.1038/nchembio.419. View

Kurokawa M, Fissore R . ICSI-generated mouse zygotes exhibit altered calcium oscillations, inositol 1,4,5-trisphosphate receptor-1 down-regulation, and embryo development. Mol Hum Reprod. 2003; 9(9):523-33. DOI: 10.1093/molehr/gag072. View

De Paola M, Bello O, Michaut M . Cortical Granule Exocytosis Is Mediated by Alpha-SNAP and N-Ethilmaleimide Sensitive Factor in Mouse Oocytes. PLoS One. 2015; 10(8):e0135679. PMC: 4534440. DOI: 10.1371/journal.pone.0135679. View

Lee H, Yoon S, Lykke-Hartmann K, Fissore R, Carvacho I . TRPV3 channels mediate Ca²⁺ influx induced by 2-APB in mouse eggs. Cell Calcium. 2016; 59(1):21-31. DOI: 10.1016/j.ceca.2015.12.001. View

Navarrete F, Alvau A, Lee H, Levin L, Buck J, Leon P . Transient exposure to calcium ionophore enables in vitro fertilization in sterile mouse models. Sci Rep. 2016; 6:33589. PMC: 5024339. DOI: 10.1038/srep33589. View

10.

Que E, Duncan F, Bayer A, Philips S, Roth E, Bleher R . Zinc sparks induce physiochemical changes in the egg zona pellucida that prevent polyspermy. Integr Biol (Camb). 2017; 9(2):135-144. PMC: 5439353. DOI: 10.1039/c6ib00212a. View

11.

Escrich L, Grau N, de Los Santos M, Romero J, Pellicer A, Escriba M . The dynamics of in vitro maturation of germinal vesicle oocytes. Fertil Steril. 2012; 98(5):1147-51. DOI: 10.1016/j.fertnstert.2012.07.1116. View

12.

Xiao S, Duncan F, Bai L, Nguyen C, Shea L, Woodruff T . Size-specific follicle selection improves mouse oocyte reproductive outcomes. Reproduction. 2015; 150(3):183-92. PMC: 4527888. DOI: 10.1530/REP-15-0175. View

13.

Green K, Kim J, Wang W, Day B, Prather R . Effect of myosin light chain kinase, protein kinase A, and protein kinase C inhibition on porcine oocyte activation. Biol Reprod. 1999; 61(1):111-9. DOI: 10.1095/biolreprod61.1.111. View

14.

Zhang N, Duncan F, Que E, OHalloran T, Woodruff T . The fertilization-induced zinc spark is a novel biomarker of mouse embryo quality and early development. Sci Rep. 2016; 6:22772. PMC: 4796984. DOI: 10.1038/srep22772. View

15.

Bernhardt M, Kim A, OHalloran T, Woodruff T . Zinc requirement during meiosis I-meiosis II transition in mouse oocytes is independent of the MOS-MAPK pathway. Biol Reprod. 2010; 84(3):526-36. PMC: 3043131. DOI: 10.1095/biolreprod.110.086488. View

16.

Suzuki T, Yoshida N, Suzuki E, Okuda E, Perry A . Full-term mouse development by abolishing Zn2+-dependent metaphase II arrest without Ca2+ release. Development. 2010; 137(16):2659-69. DOI: 10.1242/dev.049791. View

17.

Lord T, Aitken R . Oxidative stress and ageing of the post-ovulatory oocyte. Reproduction. 2013; 146(6):R217-27. DOI: 10.1530/REP-13-0111. View

18.

Que E, Bleher R, Duncan F, Kong B, Gleber S, Vogt S . Quantitative mapping of zinc fluxes in the mammalian egg reveals the origin of fertilization-induced zinc sparks. Nat Chem. 2015; 7(2):130-9. PMC: 4315321. DOI: 10.1038/nchem.2133. View

19.

Kong B, Duncan F, Que E, Xu Y, Vogt S, OHalloran T . The inorganic anatomy of the mammalian preimplantation embryo and the requirement of zinc during the first mitotic divisions. Dev Dyn. 2015; 244(8):935-47. PMC: 4617753. DOI: 10.1002/dvdy.24285. View

20.

Bernhardt M, Kong B, Kim A, OHalloran T, Woodruff T . A zinc-dependent mechanism regulates meiotic progression in mammalian oocytes. Biol Reprod. 2012; 86(4):114. PMC: 3338659. DOI: 10.1095/biolreprod.111.097253. View