MAPK3/1 (ERK1/2) and myosin light chain kinase in mammalian eggs affect myosin-II function and regulate the metaphase II state in a calcium- and zinc-dependent manner

Lauren A. McGinnis, Hyo J. Lee, Douglas Robinson, Janice Perry Evans

Research output: Contribution to journalArticle

Abstract

Vertebrate eggs are arrested at metaphase of meiosis II, a state classically known as cytostatic factor arrest. Maintenance of this arrest until the time of fertilization and then fertilizationinduced exit from metaphase II are crucial for reproductive success. Another key aspect of this meiotic arrest and exit is regulation of the metaphase II spindle, which must be appropriately localized adjacent to the egg cortex during metaphase II and then progress into successful asymmetric cytokinesis to produce the second polar body. This study examined the mitogen-activated protein kinases MAPK3 and MAPK1 (also known as ERK1/2) as regulators of these two related aspects of mammalian egg biology, specifically testing whether this MAPK pathway affected myosin-II function and whether myosin-II perturbation would produce some of the same effects as MAPK pathway perturbation. Inhibition of the MEK1/2-MAPK pathway with U0126 leads to reduced levels of phosphorylated myosin-regulatory light chain (pMRLC) and causes a reduction in cortical tension, effects that are mimicked by treatment with the myosin light chain kinase (MLCK) inhibitor ML-7. These data indicate that one mechanism by which the MAPK pathway acts in eggs is by affecting myosin-II function. We further show that MAPK or MLCK inhibition induces loss of normal cortical spindle localization or parthenogenetic egg activation. This parthenogenesis is dependent on cytosolic and extracellular calcium and can be rescued by hyperloading eggs with zinc, suggesting that these effects of inhibition of MLCK or the MAPK pathway are linked with dysregulation of ion homeostasis.

Original languageEnglish (US)
Article number146
JournalBiology of Reproduction
Volume92
Issue number6
DOIs
StatePublished - Jun 1 2015

Fingerprint

Myosin Type II
Myosin-Light-Chain Kinase
Metaphase
Eggs
Zinc
Calcium
Ovum
Proto-Oncogene Proteins c-mos
Parthenogenesis
Polar Bodies
Myosin Light Chains
Cytokinesis
Mitogen-Activated Protein Kinase 3
Mitogen-Activated Protein Kinase 1
Meiosis
Fertilization
Vertebrates
Homeostasis
Maintenance
Ions

Keywords

  • Calcium
  • Cytoskeleton
  • Egg activation
  • MAPK
  • Myosin-II
  • Parthenogenesis
  • Spindle
  • Zinc

ASJC Scopus subject areas

  • Cell Biology

Cite this

MAPK3/1 (ERK1/2) and myosin light chain kinase in mammalian eggs affect myosin-II function and regulate the metaphase II state in a calcium- and zinc-dependent manner. / McGinnis, Lauren A.; Lee, Hyo J.; Robinson, Douglas; Evans, Janice Perry.

In: Biology of Reproduction, Vol. 92, No. 6, 146, 01.06.2015.

Research output: Contribution to journalArticle

@article{2f7f9e05c8c24dcea42009070b875c71,
title = "MAPK3/1 (ERK1/2) and myosin light chain kinase in mammalian eggs affect myosin-II function and regulate the metaphase II state in a calcium- and zinc-dependent manner",
abstract = "Vertebrate eggs are arrested at metaphase of meiosis II, a state classically known as cytostatic factor arrest. Maintenance of this arrest until the time of fertilization and then fertilizationinduced exit from metaphase II are crucial for reproductive success. Another key aspect of this meiotic arrest and exit is regulation of the metaphase II spindle, which must be appropriately localized adjacent to the egg cortex during metaphase II and then progress into successful asymmetric cytokinesis to produce the second polar body. This study examined the mitogen-activated protein kinases MAPK3 and MAPK1 (also known as ERK1/2) as regulators of these two related aspects of mammalian egg biology, specifically testing whether this MAPK pathway affected myosin-II function and whether myosin-II perturbation would produce some of the same effects as MAPK pathway perturbation. Inhibition of the MEK1/2-MAPK pathway with U0126 leads to reduced levels of phosphorylated myosin-regulatory light chain (pMRLC) and causes a reduction in cortical tension, effects that are mimicked by treatment with the myosin light chain kinase (MLCK) inhibitor ML-7. These data indicate that one mechanism by which the MAPK pathway acts in eggs is by affecting myosin-II function. We further show that MAPK or MLCK inhibition induces loss of normal cortical spindle localization or parthenogenetic egg activation. This parthenogenesis is dependent on cytosolic and extracellular calcium and can be rescued by hyperloading eggs with zinc, suggesting that these effects of inhibition of MLCK or the MAPK pathway are linked with dysregulation of ion homeostasis.",
keywords = "Calcium, Cytoskeleton, Egg activation, MAPK, Myosin-II, Parthenogenesis, Spindle, Zinc",
author = "McGinnis, {Lauren A.} and Lee, {Hyo J.} and Douglas Robinson and Evans, {Janice Perry}",
year = "2015",
month = "6",
day = "1",
doi = "10.1095/biolreprod.114.127027",
language = "English (US)",
volume = "92",
journal = "Biology of Reproduction",
issn = "0006-3363",
publisher = "Society for the Study of Reproduction",
number = "6",

}

TY - JOUR

T1 - MAPK3/1 (ERK1/2) and myosin light chain kinase in mammalian eggs affect myosin-II function and regulate the metaphase II state in a calcium- and zinc-dependent manner

AU - McGinnis, Lauren A.

AU - Lee, Hyo J.

AU - Robinson, Douglas

AU - Evans, Janice Perry

PY - 2015/6/1

Y1 - 2015/6/1

N2 - Vertebrate eggs are arrested at metaphase of meiosis II, a state classically known as cytostatic factor arrest. Maintenance of this arrest until the time of fertilization and then fertilizationinduced exit from metaphase II are crucial for reproductive success. Another key aspect of this meiotic arrest and exit is regulation of the metaphase II spindle, which must be appropriately localized adjacent to the egg cortex during metaphase II and then progress into successful asymmetric cytokinesis to produce the second polar body. This study examined the mitogen-activated protein kinases MAPK3 and MAPK1 (also known as ERK1/2) as regulators of these two related aspects of mammalian egg biology, specifically testing whether this MAPK pathway affected myosin-II function and whether myosin-II perturbation would produce some of the same effects as MAPK pathway perturbation. Inhibition of the MEK1/2-MAPK pathway with U0126 leads to reduced levels of phosphorylated myosin-regulatory light chain (pMRLC) and causes a reduction in cortical tension, effects that are mimicked by treatment with the myosin light chain kinase (MLCK) inhibitor ML-7. These data indicate that one mechanism by which the MAPK pathway acts in eggs is by affecting myosin-II function. We further show that MAPK or MLCK inhibition induces loss of normal cortical spindle localization or parthenogenetic egg activation. This parthenogenesis is dependent on cytosolic and extracellular calcium and can be rescued by hyperloading eggs with zinc, suggesting that these effects of inhibition of MLCK or the MAPK pathway are linked with dysregulation of ion homeostasis.

AB - Vertebrate eggs are arrested at metaphase of meiosis II, a state classically known as cytostatic factor arrest. Maintenance of this arrest until the time of fertilization and then fertilizationinduced exit from metaphase II are crucial for reproductive success. Another key aspect of this meiotic arrest and exit is regulation of the metaphase II spindle, which must be appropriately localized adjacent to the egg cortex during metaphase II and then progress into successful asymmetric cytokinesis to produce the second polar body. This study examined the mitogen-activated protein kinases MAPK3 and MAPK1 (also known as ERK1/2) as regulators of these two related aspects of mammalian egg biology, specifically testing whether this MAPK pathway affected myosin-II function and whether myosin-II perturbation would produce some of the same effects as MAPK pathway perturbation. Inhibition of the MEK1/2-MAPK pathway with U0126 leads to reduced levels of phosphorylated myosin-regulatory light chain (pMRLC) and causes a reduction in cortical tension, effects that are mimicked by treatment with the myosin light chain kinase (MLCK) inhibitor ML-7. These data indicate that one mechanism by which the MAPK pathway acts in eggs is by affecting myosin-II function. We further show that MAPK or MLCK inhibition induces loss of normal cortical spindle localization or parthenogenetic egg activation. This parthenogenesis is dependent on cytosolic and extracellular calcium and can be rescued by hyperloading eggs with zinc, suggesting that these effects of inhibition of MLCK or the MAPK pathway are linked with dysregulation of ion homeostasis.

KW - Calcium

KW - Cytoskeleton

KW - Egg activation

KW - MAPK

KW - Myosin-II

KW - Parthenogenesis

KW - Spindle

KW - Zinc

UR - http://www.scopus.com/inward/record.url?scp=84936929799&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84936929799&partnerID=8YFLogxK

U2 - 10.1095/biolreprod.114.127027

DO - 10.1095/biolreprod.114.127027

M3 - Article

C2 - 25904014

AN - SCOPUS:84936929799

VL - 92

JO - Biology of Reproduction

JF - Biology of Reproduction

SN - 0006-3363

IS - 6

M1 - 146

ER -