Dynamic alterations in H4K12 acetylation during meiotic maturation and after parthenogenetic activation of mouse oocytes

SummaryThe aim of the study was to investigate the continuous changing pattern of H4K12 acetylation, and the expression levels of histone acetyltransferases (HATs) and histone deacetyltransferases (HDACs) in mouse oocytes during meiosis and after parthenogenetic activation (PA). The immunofluorescence results showed hyperacetylation of lysine-12 on histone H4 (H4K12) in the germinal vesicle (GV) oocytes that then decreased during germinal vesicle breakdown (GVBD), and disappeared in metaphase II (MII). However, it reappeared in the early 1-cell embryos derived after 4 h of PA. The expression levels of some selected HATs and HDACs also validated the changing pattern of H4K12 acetylation during meiosis and PA. In conclusion, H4K12 is deacetylated in GVBD and MII, and re-hyperacetylated after PA.

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Meiotic maturation of mouse oocytes in vitro: inhibition of maturation at specific stages of nuclear progression

Journal of Cell Science ◽

10.1242/jcs.22.3.531 ◽

1976 ◽

Vol 22 (3) ◽

pp. 531-545

Author(s):

P.M. Wassarman ◽

W.J. Josefowicz ◽

G.E. Letourneau

Keyword(s):

Cyclic Amp ◽

Cytochalasin B ◽

Polar Body ◽

Germinal Vesicle ◽

Meiotic Maturation ◽

Dibutyryl Cyclic Amp ◽

Germinal Vesicle Breakdown ◽

Mouse Oocytes ◽

First Polar Body

In vitro studies of meiotic maturation of mouse oocytes have been carried out in the presence of several drugs. The individual steps of nuclear progression, including dissolution of the nuclear (germinal vesicle) membrane, condensation of dictyate chromatin into compact bivalents, formation of the first metaphase spindle, and extrusion of the first polar body, are each susceptible to one or more of these drugs. Germinal vesicle breakdown, the initial morphological feature characteristic of meiotic maturation, is inhibited by dibutyryl cyclic AMP. However, even in the presence of dibutyryl cyclic AMP, the nuclear membrane becomes extremely convoluted and condensation of chromatin is initiated but aborts at a stage short of compact bivalents. Germinal vesicle breakdown and chromatin condensation take place in an apparently normal manner in the presence of puromycin, Colcemid, or cytochalasin B. Nuclear progression is blocked at the circular bivalent stage when oocytes are cultured continuously in the presence of puromycin or Colcemid, whereas oocytes cultured in the presence of cytochalasin B proceed to the first meiotic metaphase, form an apparently normal spindle, and arrest. Emission of a polar body is inhibited by all of these drugs. The inhibitory effects of these drugs on meiotic maturation are reversible to varying degrees dependent upon the duration of exposure to the drug and upon the nature of the drug. These studies suggest that dissolution of the mouse oocyte's germinal vesicle and condensation of chromatin are not dependent upon concomitant protein synthesis or upon microtubules. On the other hand, the complete condensation of chromatin into compact bivalents apparently requires breakdown of the germinal vesicle. Failure of homologous chromosomes to separate after normal alignment on the meiotic spindle in the presence of cytochalasin B suggest that microfilaments may be involved in nuclear progression at this stage of maturation. Cytokinesis, in the form of polar body formation, is blocked when any one of the earlier events of maturation fails to take place.

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Capacity of mouse oocytes to become activated depends on completion of cytoplasmic but not nuclear meiotic maturation

Zygote ◽

10.1017/s0967199400002379 ◽

1995 ◽

Vol 3 (1) ◽

pp. 45-55 ◽

Cited By ~ 8

Author(s):

Joise M.L. McConnell ◽

Liz Campbell ◽

Caroline Vincent

Keyword(s):

Chromosomal Rearrangements ◽

Polar Body ◽

Calcium Ionophore ◽

Germinal Vesicle ◽

Calcium Ionophore A23187 ◽

Meiotic Maturation ◽

Ionophore A23187 ◽

Germinal Vesicle Breakdown ◽

Mouse Oocytes ◽

Polar Body Extrusion

SummaryThe ability of mouse oocytes to become activated after exposure too the calcium ionophore A23187 has been investigated at different stages of meiotic maturation. The potential to respond to ionophore has been studied in relation to the time since resumption of meiotic maturation, the chromosomal conformation of the DNA within each cell and the protein synthetic profile of the maturing oocyte. Our studies demonstrate that when maturing oocytes from an MF1 strain of mice were treated with A23187 activation occured only in oocytes which had reached second meiotic metaphase (MII). However, development of the ability to respond to ionophore was not dependent on an orderly progression through normal chromosomal rearrangements such as separation at metaphase I (MI) and subsequent polar body extrusion, since there process could be prevented and the capacity to be activated became apparent in such oocytes at a time when control cells had reached MII. These data suggest that the ability to respond to ionophore depends on the development of a cytoplasmic or complex capable of monitoring the time since initiation of germinal vesicle breakdown. Metabolic radiolabelling of oocytes which were able to respond to calcium ionophore, even though they had been prevented from undergoing normal chromosomal rearrangements, showed them to be synthesising a group of proteins known as the 35 kDa complex.

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Effects of EDTA saturated with Ca2+ (Ca-EDTA) on pig, bovine and mouse oocytes at the germinal vesicle stage during maturation culture and the involvement of chelation of Zn2+ in pronuclear formation induction by Ca-EDTA

Reproduction ◽

10.1530/rep.0.1240235 ◽

2002 ◽

pp. 235-240 ◽

Cited By ~ 7

Author(s):

T Azuma ◽

T Kondo ◽

S Ikeda ◽

H Imai ◽

M Yamada

Keyword(s):

Polar Body ◽

Calf Serum ◽

Germinal Vesicle ◽

Germinal Vesicle Breakdown ◽

Parthenogenetic Activation ◽

Mouse Oocytes ◽

Maturation Medium ◽

Second Polar Body ◽

Pronuclear Formation ◽

Bovine Oocytes

EDTA saturated with Ca(2+), Fe(3+) or Cu(2+) can induce parthenogenetic activation of pig oocytes at the germinal vesicle stage, whereas EDTA saturated with Zn(2+), which is unable to chelate Zn(2+), does not, indicating that chelation of Zn(2+) with EDTA saturated with Ca(2+) (Ca-EDTA) in maturing pig oocytes plays a pivotal role in the induction of parthenogenetic activation of oocytes. In the present study, the involvement of Zn(2+) chelation in the induction of parthenogenetic activation of pig oocytes at the germinal vesicle stage was confirmed first by examining the effects of concomitant addition of Zn(2+), Cu(2+) or Ni(2+) at various concentrations together with 1 mmol Ca-EDTA l(-1) to the maturation medium. The titration experiments revealed that the pronuclear formation induced by 1 mmol Ca-EDTA l(-1) was completely inhibited by the addition of > 30 micromol Zn(2+) l(-1) to the medium, but not by the addition of Cu(2+) and Ni(2+) at any concentration examined. Second, bovine and mouse oocytes at the germinal vesicle stage were cultured in medium with or without 1 mmol Ca-EDTA l(-1) for 48 h to examine the effects of Ca-EDTA treatment on these oocytes during maturation culture. Most (70-86%) of the bovine oocytes that underwent germinal vesicle breakdown matured to the MII stage via the MI phase, regardless of whether Ca-EDTA was present for the first 24 h of culture. However, 61% of oocytes that had been cultured with Ca-EDTA for 48 h formed a pronucleus without a second polar body, whereas oocytes cultured in the absence of Ca-EDTA were not observed to form a pronucleus at any time during culture. However, even when mouse oocytes at the germinal vesicle stage were cultured for up to 48 h in maturation medium containing Ca-EDTA, pronuclear formation was not observed. Finally, when bovine oocytes that had been cultured with 1 mmol Ca-EDTA l(-1) for 48 h from the germinal vesicle stage were cultured further in medium without Ca-EDTA that was supplemented with 5% fetal calf serum, only 26% of the oocytes developed to the cleaved stage, and none could develop further.

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Triphenyltin chloride induces spindle microtubule depolymerisation and inhibits meiotic maturation in mouse oocytes

Reproduction Fertility and Development ◽

10.1071/rd12332 ◽

2014 ◽

Vol 26 (8) ◽

pp. 1084 ◽

Cited By ~ 2

Author(s):

Yu-Ting Shen ◽

Yue-Qiang Song ◽

Xiao-Qin He ◽

Fei Zhang ◽

Xin Huang ◽

...

Keyword(s):

Polar Body ◽

Meiotic Maturation ◽

Dependent Manner ◽

Germinal Vesicle Breakdown ◽

Mouse Oocytes ◽

First Polar Body ◽

Triphenyltin Chloride ◽

Dose Dependent

Meiosis produces haploid gametes for sexual reproduction. Triphenyltin chloride (TPTCL) is a highly bioaccumulated and toxic environmental oestrogen; however, its effect on oocyte meiosis remains unknown. We examined the effect of TPTCL on mouse oocyte meiotic maturation in vitro and in vivo. In vitro, TPTCL inhibited germinal vesicle breakdown (GVBD) and first polar body extrusion (PBE) in a dose-dependent manner. The spindle microtubules completely disassembled and the chromosomes condensed after oocytes were exposed to 5 or 10 μg mL–1 TPTCL. γ-Tubulin protein was abnormally localised near chromosomes rather than on the spindle poles. In vivo, mice received TPTCL by oral gavage for 10 days. The general condition of the mice deteriorated and the ovary coefficient was reduced (P < 0.05). The number of secondary and mature ovarian follicles was significantly reduced by 10 mg kg–1 TPTCL (P < 0.05). GVBD decreased in a non-significant, dose-dependent manner (P > 0.05). PBE was inhibited with 10 mg kg–1 TPTCL (P < 0.05). The spindles of in vitro and in vivo metaphase II oocytes were disassembled with 10 mg kg–1 TPTCL. These results suggest that TPTCL seriously affects meiotic maturation by disturbing cell-cycle progression, disturbing the microtubule cytoskeleton and inhibiting follicle development in mouse oocytes.

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Replicating DNA does not block germinal vesicle breakdown in mouse oocytes

Journal of Experimental Zoology ◽

10.1002/jez.1402720310 ◽

1995 ◽

Vol 272 (3) ◽

pp. 245-248 ◽

Cited By ~ 12

Author(s):

J. Fulka ◽

R. M. Moor ◽

J. Fulka

Keyword(s):

Germinal Vesicle ◽

Germinal Vesicle Breakdown ◽

Mouse Oocytes

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Pleiotropic effect of okadaic acid on maturing mouse oocytes

Development ◽

10.1242/dev.112.4.971 ◽

1991 ◽

Vol 112 (4) ◽

pp. 971-980 ◽

Cited By ~ 1

Author(s):

H. Alexandre ◽

A. Van Cauwenberge ◽

Y. Tsukitani ◽

J. Mulnard

Keyword(s):

Protein Kinase ◽

Okadaic Acid ◽

Protein Phosphatases ◽

Chromatin Condensation ◽

Polar Body ◽

Germinal Vesicle ◽

Inhibitory Effect ◽

Negative Control ◽

Germinal Vesicle Breakdown ◽

Mouse Oocytes

Okadaic acid (OA), a potent inhibitor of types 1 and 2A protein phosphatases, was shown recently to induce chromatin condensation and germinal vesicle breakdown (GVBD) in mouse oocytes arrested at the dictyate stage by dibutyryl cAMP (dbcAMP), isobutyl methylxanthine (IBMX) and 12,13-phorbol dibutyrate (PDBu). We confirm these results using IBMX and another phorbol diester, 12-O-tetradecanoylphorbol-13-acetate (TPA) and show that OA also bypasses the inhibitory effect of 6-dimethylaminopurine (6-DMAP). It has been concluded that protein phosphatases 1 and/or 2A (PP1, 2A), involved in the negative control of MPF activation, are thus operating downstream from both the protein kinase A and protein kinase C catalysed phosphorylation steps that prevent the breakdown of GV. Similar enzymatic activities are also able to counteract the general inhibition of protein phosphorylation. However, PP1 and/or PP2A are positively involved in the activation of pericentriolar material (PCM) into microtubule organizing centres (MTOCs). This explains the inhibitory effect of OA on spindle assembly. Finally, OA interferes with the integrity and/or function of actomyosin filaments. This results in a dramatic ruffling of the plasma membrane leading to the internalization of large vacuoles, the inhibition of chromosome centrifugal displacement and, consequently, the prevention of polar body extrusion.

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The Role of Tissue Transglutaminase in the Germinal Vesicle Breakdown of Mouse Oocytes

Biochemical and Biophysical Research Communications ◽

10.1006/bbrc.2001.5381 ◽

2001 ◽

Vol 286 (2) ◽

pp. 229-234 ◽

Cited By ~ 12

Author(s):

Sung Woo Kim ◽

Zee-Won Lee ◽

ChangKyu Lee ◽

Kyung Soon Im ◽

Kwon-Soo Ha

Keyword(s):

Tissue Transglutaminase ◽

Germinal Vesicle ◽

Germinal Vesicle Breakdown ◽

Mouse Oocytes

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The dynamics of cyclin B1 distribution during meiosis I in mouse oocytes

Reproduction ◽

10.1530/rep.1.00192 ◽

2004 ◽

Vol 128 (2) ◽

pp. 153-162 ◽

Cited By ~ 40

Author(s):

Petros Marangos ◽

John Carroll

Keyword(s):

Fluorescent Protein ◽

Germinal Vesicle ◽

Cyclin B1 ◽

Nuclear Accumulation ◽

Leptomycin B ◽

Germinal Vesicle Breakdown ◽

Mouse Oocytes ◽

Living Mouse ◽

Green Fluorescent ◽

Meiosis I

Cdk1-cyclin B1 kinase activity drives oocytes through meiotic maturation. It is regulated by the phosphorylation status of cdk1 and by its spatial organisation. Here we used a cyclin B1-green fluorescent protein (GFP) fusion protein to examine the dynamics of cdk1-cyclin B1 distribution during meiosis I (MI) in living mouse oocytes. Microinjection of cyclin B1-GFP accelerated germinal vesicle breakdown (GVBD) and, as previously described, overrides cAMP-mediated meiotic arrest. GVBD was pre-empted by a translocation of cyclin B1-GFP from the cytoplasm to the germinal vesicle (GV). After nuclear accumulation, cyclin B1-GFP localised to the chromatin. The localisation of cyclin B1-GFP is governed by nuclear import and export. In GV intact oocytes, cyclin export was demonstrated by showing that cyclin B1-GFP injected into the GV is exported to the cytoplasm while a similar size dextran is retained. Import was revealed by the finding that cyclin B1-GFP accumulated in the GV when export was inhibited using leptomycin B. These studies show that GVBD in mouse oocytes is sensitive to cyclin B1 abundance and that the changes in distribution of cyclin B1 contribute to progression through MI.

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The effect of PD98059 on MAPK regulation in cumulus-enclosed and cumulus-free mouse oocytes

Zygote ◽

10.1017/s0967199403001084 ◽

2003 ◽

Vol 11 (1) ◽

pp. 61-68 ◽

Cited By ~ 6

Author(s):

Jaroslav Kalous ◽

Michal Kubelka ◽

Jan Motlík

Keyword(s):

Germinal Vesicle ◽

Cumulus Cells ◽

Experimental Conditions ◽

Germinal Vesicle Breakdown ◽

Mapk Activation ◽

Mapk Phosphorylation ◽

Kinase Activation ◽

Mouse Oocytes ◽

Significant Difference ◽

Epidermal Growth

The effect of the p42/44 mitogen-activated kinase (MAPK) inhibitor, PD98059, on MAPK activation and meiosis resumption in mouse oocytes was studied. When germinal vesicle (GV)-stage denuded oocytes (DOs) were cultured continuously in 50 μM PD98059, germinal vesicle breakdown (GVBD) was postponed for 2-3 h. MAPK phosphorylation and activation was delayed as well. However, PD98059 did not impair histone H1 kinase activation. After 14 h of culture there was no significant difference in the rate of DOs reaching metaphase II (MII) arrest in either control or experimental conditions. The effect of PD98059 on MAPK inhibition was further tested in epidermal growth factor (EGF)-treated oocyte–cumulus complexes (OCCs). Exposure of GV-stage OCCs for 5 min to EGF (10 ng/ml) induced a considerable increase in MAPK phosphorylation. After OCCs were further cultured in 50 μM PD98059 a rapid dephosphorylation of MAPK was induced. Already after 1 min of treatment the non-phosphorylated form of MAPK dominated, indicating the high effectivity of PD98059. This result indicates that short EGF/PD98059 treatment of OCCs induced MAPK phosphorylation/dephosphorylation in cumulus cells only. As only a transient delay in MAPK phosphorylation and activation was observed in PD98059-treated DOs we conclude that there is also another PD98059-nonsensitive pathway(s) leading to MAPK activation in mouse oocytes. The data obtained suggest that meiosis resumption in mouse oocytes is somehow influenced by the MEK/MAPK activation pathway.

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