Oocyte Maturation and Furrow Formation in an Unfertilized Egg by Fusion with a Fertilized Egg or Blastomeres in the Ascidian, Ascidia sydneiensis divisa. (ascidian egg/cell fusion/oocyte maturation/polar body extrusion/furrow formation)

Abstract Background Ral family is a member of Ras-like GTPase superfamily, which includes RalA and RalB. RalA/B play important roles in many cell biological functions, including cytoskeleton dynamics, cell division, membrane transport, gene expression and signal transduction. However, whether RalA/B involve into the mammalian oocyte meiosis is still unclear. This study aimed to explore the roles of RalA/B during mouse oocyte maturation. Results Our results showed that RalA/B expressed at all stages of oocyte maturation, and they were enriched at the spindle periphery area after meiosis resumption. The injection of RalA/B siRNAs into the oocytes significantly disturbed the polar body extrusion, indicating the essential roles of RalA/B for oocyte maturation. We observed that in the RalA/B knockdown oocytes the actin filament fluorescence intensity was significantly increased at the both cortex and cytoplasm, and the chromosomes were failed to locate near the cortex, indicating that RalA/B regulate actin dynamics for spindle migration in mouse oocytes. Moreover, we also found that the Golgi apparatus distribution at the spindle periphery was disturbed after RalA/B depletion. Conclusions In summary, our results indicated that RalA/B affect actin dynamics for chromosome positioning and Golgi apparatus distribution in mouse oocytes.

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Involvement of dynamin 2 in actin-based polar-body extrusion during porcine oocyte maturation

Molecular Reproduction and Development ◽

10.1002/mrd.22341 ◽

2014 ◽

Vol 81 (8) ◽

pp. 725-734 ◽

Cited By ~ 6

Author(s):

Yu Zhang ◽

Qiao-Chu Wang ◽

Jun Han ◽

Rui Cao ◽

Xiang-Shun Cui ◽

...

Keyword(s):

Oocyte Maturation ◽

Polar Body ◽

Porcine Oocyte ◽

Polar Body Extrusion ◽

Dynamin 2

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Comparison of the toxic effects of different mycotoxins on porcine and mouse oocyte meiosis

PeerJ ◽

10.7717/peerj.5111 ◽

2018 ◽

Vol 6 ◽

pp. e5111 ◽

Cited By ~ 7

Author(s):

Yujie Lu ◽

Yue Zhang ◽

Jia-Qian Liu ◽

Peng Zou ◽

Lu Jia ◽

...

Keyword(s):

Oocyte Maturation ◽

Animal Feed ◽

Polar Body ◽

Oocyte Quality ◽

Mouse Oocyte ◽

Toxic Effects ◽

Mouse Oocytes ◽

Oocyte Meiosis ◽

Porcine Oocyte ◽

Polar Body Extrusion

Background Aflatoxin B1 (AFB1), deoxynivalenol (DON), HT-2, ochratoxin A (OTA), zearalenone (ZEA) are the most common mycotoxins that are found in corn-based animal feed which have multiple toxic effects on animals and humans. Previous studies reported that these mycotoxins impaired mammalian oocyte quality. However, the effective concentrations of mycotoxins to animal oocytes were different. Methods In this study we aimed to compare the sensitivity of mouse and porcine oocytes to AFB1, DON, HT-2, OTA, and ZEA for mycotoxin research. We adopted the polar body extrusion rate of mouse and porcine oocyte as the standard for the effects of mycotoxins on oocyte maturation. Results and Discussion Our results showed that 10 μM AFB1 and 1 μM DON significantly affected porcine oocyte maturation compared with 50 μM AFB1 and 2 μM DON on mouse oocytes. However, 10 nM HT-2 significantly affected mouse oocyte maturation compared with 50 nM HT-2 on porcine oocytes. Moreover, 5 μM OTA and 10 μM ZEA significantly affected porcine oocyte maturation compared with 300 μM OTA and 50 μM ZEA on mouse oocytes. In summary, our results showed that porcine oocytes were more sensitive to AFB1, DON, OTA, and ZEA than mouse oocytes except HT-2 toxin.

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313IN VITRO MATURATION AND FERTILIZATION OF OOCYTES COLLECTED FROM UNSTIMULATED MACACA NEMISTRINA OVARIES

Reproduction Fertility and Development ◽

10.1071/rdv16n1ab313 ◽

2004 ◽

Vol 16 (2) ◽

pp. 276

Author(s):

E.S. Hayes ◽

E.C. Curnow

Keyword(s):

Oocyte Maturation ◽

Polar Body ◽

Pantothenic Acid ◽

Macaca Nemestrina ◽

Chi Square ◽

Maturation In Vitro ◽

First Polar Body ◽

Chi Square Analysis ◽

Polar Body Extrusion

Reports describing the IVM of Macaca nemestrina (Mn) oocytes are limited (Cranfield MR et al. 1989 Zoo. Biol. (Supp. 1), 33). The use of gonadotrophins (Gnt) for IVM of non-human primate (NHP) oocytes is common but the concentrations used are often high (8–40IUmL−1) and the species of origin and biological activity of Gnt varies (Schramm RD and Paprocki AM, 2000 Hum. Reprod. 15, 2411). We have compared two different IVM systems with human Gnt on maturation and fertilization of oocytes collected from unstimulated Mn ovaries (n=6–10 animals). Oocytes were subjected to IVM in modified (minus PVA and pantothenic acid, plus 20 amino acids) HECM−10+15% FCS (Zheng P et al., 2001 Mol. Reprod. Dev. 58, 348) for a) 36h in the presence (mHECM+36, n=322) or absence (mHECM−36, n=99) of FSH and LH applied sequentially (FSH 1IUmL−1 0–24h; 10IUmL−1 FSH and LH 24–36h) or b) 24h in the presence (mHECM+24, n=119) or absence (mHECM−24, n=56) of static concentrations of Gnt (FSH and LH 1IUmL−1 0–24h; no Gnt 24–30h). Oocytes exhibiting first polar body extrusion at 36 and 30h were recorded as mature (MII) and subjected to IVF in HTF+BSA (3mg mL−1) with Mn sperm pretreated with 1.0mM caffeine and 0.1mM dbcAMP. Fertilized oocytes (pronuclei and/or 2nd polar body extrusion) were cultured in sequential culture medium for 48h, assessed for cleavage and either fixed or frozen. Proportional data (mature/total, fertilized/mature or cleaved/fertilized) were compared by chi-square analysis and are reported as percentages. Oocytes cultured in mHECM+36 and mHECM−36 exhibited similar rates of GVBD (58.7% v. 53.5%) but the percentage of MII oocytes was significantly higher (P=0.0244) in mHECM+36 (41.3%) v. mHECM−36 (28.3%). Fertilization rates were comparable between mHECM+36 (61.5%) and mHECM−36 (60.9%), whereas cleavage rates were significantly higher (P=0.0004) in mHECM+36 (74.6%) v. HECM−36 (21.4%). Oocytes cultured in mHECM+24 and mHECM−24 exhibited similar rates of GVBD (76.5% v. 62.5%) but the proportion of MII oocytes was significantly higher (P=0.0159) in mHECM+24 (55.5%) v. mHECM−24 (35.7%). Fertilization and cleavage rates were comparable between mHECM+24 (58.8% v. 63.3%) and mHECM−24 (50.0% v. 42.8%). A comparison between mHECM+36 and mHECM+24 indicated a significantly lower (P=0.0005) percentage of GV oocytes and a significantly higher (P=0.0096) percentage of MII oocytes in mHECM+24 (23.5% v. 55.5%) compared to mHECM+36 (41.3% v. 41.3%). Fertilization and cleavage rates were not significantly different between mHECM+36 and mHECM+24. Oocyte maturation and fertilization and embryo cleavage were not different for mHECM−36 and mHECM−24 (P=0.3138–0.8202). Mn oocytes exhibit high rates of Gnt-independent GVBD (52.5%–53.5%) and maturation (28.3%–35.7%) in vitro, and maturation rates were improved in Gnt supplemented maturation medium. However, reduced exposure to lower concentrations of FSH and increased exposure to lower concentrations of LH was associated with higher rates of oocyte maturation in vitro. The use of lower concentrations of FSH and LH for reduced periods may improve IVM of NHP oocytes. This work was supported by the Tissue Distribution Program of the WaNPRC (NIH grant # R00166).

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The role of propofol on mouse oocyte meiotic maturation and early embryo development

Zygote ◽

10.1017/s0967199418000163 ◽

2018 ◽

Vol 26 (4) ◽

pp. 261-269

Author(s):

Xia-Guang Duan ◽

Zai-Qing Huang ◽

Chun-Guang Hao ◽

Xiao-Jun Zhi ◽

Xiao-Bing Qi ◽

...

Keyword(s):

Embryo Development ◽

Oocyte Maturation ◽

Polar Body ◽

Oocyte Retrieval ◽

Early Embryo ◽

Mouse Oocyte ◽

Early Embryo Development ◽

Intravenous Anaesthetic ◽

Polar Body Extrusion

SummaryPropofol is a intravenous anaesthetic most commonly used in ultrasound oocyte retrieval. We studied if the use of propofol had an effect on mouse oocyte maturation, pregnancy, childbirth and progeny and investigated the correlation between propofol side effects and reproductive performance in mice. There was no statistical difference in mating, pregnancy, childbirth, litter size, the number of stillbirths and survival between each group (P>0.05). Propofol also had no effect on polar body extrusion in oocyte maturation as well as on pronucleus formation and, subsequently, early embryo development (P>0.05). An increased concentration of propofol had no effect on this result, although propofol at more than 0.01 mg/ml reduced polar body extrusion. Different concentrations of propofol had no effect on oocyte culture in vitro, pronucleus formation and early embryo development.

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MKlp2 inhibitior paprotrain affects polar body extrusion during mouse oocyte maturation

Reproductive Biology and Endocrinology ◽

10.1186/1477-7827-11-117 ◽

2013 ◽

Vol 11 (1) ◽

pp. 117 ◽

Cited By ~ 12

Author(s):

Jun Liu ◽

Qiao-Chu Wang ◽

Xiang-Shun Cui ◽

Zhen-Bo Wang ◽

Nam-Hyung Kim ◽

...

Keyword(s):

Oocyte Maturation ◽

Polar Body ◽

Mouse Oocyte ◽

Polar Body Extrusion

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Pterostilbene Alleviates Chlorpyrifos-Induced Damage During Porcine Oocyte Maturation

Frontiers in Cell and Developmental Biology ◽

10.3389/fcell.2021.803181 ◽

2021 ◽

Vol 9 ◽

Author(s):

Lili Guo ◽

Yongda Zhao ◽

Yanjun Huan

Keyword(s):

Oocyte Maturation ◽

Mammalian Species ◽

Polar Body ◽

Potential Effect ◽

Cell Number ◽

Free Radical Scavenger ◽

Radical Scavenger ◽

Porcine Oocyte ◽

High Level ◽

Polar Body Extrusion

Chlorpyrifos (CPF), a widely used organophosphate pesticide, is reported to severely impair mammalian reproductive system. Pterostilbene (PTS), an effective free radical scavenger, is considered as beneficial for mammalian reproduction. However, the toxicity of CPF on oocyte maturation and whether PTS can eliminate the detrimental effect of CPF on oocytes remain unclear. Here, porcine oocytes were applied to investigate the potential effect and possible mechanism of CPF and PTS during oocyte maturation. This work demonstrated that CPF significantly delayed the meiotic progression and decreased the polar body extrusion by disturbing spindle assembly and chromosome alignment and causing DNA damage in oocytes (p < 0.05). And, CPF significantly impaired oocyte cytoplasmic maturation by inducing the high level of reactive oxygen species and decreasing glutathione content (p < 0.05). Moreover, CPF significantly triggered embryo apoptosis and reduced the blastocyst rate and cell number following parthenogenetic activation (p < 0.05). Whereas CPF-exposed oocytes were treated with PTS, these defects caused by CPF were obviously rescued, and oocyte maturation and subsequent embryonic development were also significantly ameliorated (p < 0.05). In conclusion, these results revealed that CPF exerted the toxic effect on porcine oocytes, while PTS effectively alleviated CPF-induced damage on oocytes. This work provides a potential strategy to protect oocyte maturation in mammalian species.

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FASCIN regulates actin assembly for spindle movement and polar body extrusion in mouse oocyte meiosis

Journal of Cellular Physiology ◽

10.1002/jcp.30443 ◽

2021 ◽

Author(s):

Lin‐Lin Hu ◽

Meng‐Hao Pan ◽

Feng‐Lian Yang ◽

Zi‐Ao Zong ◽

Feng Tang ◽

...

Keyword(s):

Polar Body ◽

Mouse Oocyte ◽

Actin Assembly ◽

Oocyte Meiosis ◽

Polar Body Extrusion

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H1foo is essential for in vitro meiotic maturation of bovine oocytes

Zygote ◽

10.1017/s0967199414000021 ◽

2014 ◽

Vol 23 (3) ◽

pp. 416-425 ◽

Cited By ~ 13

Author(s):

Yan Yun ◽

Peng An ◽

Jing Ning ◽

Gui-Ming Zhao ◽

Wen-Lin Yang ◽

...

Keyword(s):

Oocyte Maturation ◽

Polar Body ◽

Linker Histone ◽

Meiotic Maturation ◽

Control Group ◽

Bovine Oocyte ◽

First Polar Body ◽

Effective Sirnas ◽

Bovine Oocytes

SummaryOocyte-specific linker histone, H1foo, is localized on the oocyte chromosomes during the process of meiotic maturation, and is essential for mouse oocyte maturation. Bovine H1foo has been identified, and its expression profile throughout oocyte maturation and early embryo development has been established. However, it has not been confirmed if H1foo is indispensable during bovine oocyte maturation. Effective siRNAs against H1foo were screened in HeLa cells, and then siRNA was microinjected into bovine oocytes to down-regulate H1foo expression. H1foo overexpression was achieved via mRNA injection. Reverse transcription polymerase chain reaction (RT-PCR) results indicated that H1foo was up-regulated by 200% and down-regulated by 70%. Based on the first polar body extrusion (PB1E) rate, H1foo overexpression apparently promoted meiotic progression. The knockdown of H1foo significantly impaired bovine oocyte maturation compared with H1foo overexpression and control groups (H1foo overexpression = 88.7%, H1foo siRNA = 41.2%, control = 71.2%; P < 0.05). This decrease can be rescued by co-injection of a modified H1foo mRNA that has escaped from the siRNA target. However, the H1e (somatic linker histone) overexpression had no effect on PB1E rate when compared with the control group. Therefore we concluded that H1foo is essential for bovine oocyte maturation and its overexpression stimulates the process.

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Effects of cytochalasin B on meiosis and development of fertilized and activated eggs of Sabellaria alveolata L. (Polychaete Annelid)

Development ◽

10.1242/dev.31.1.61 ◽

1974 ◽

Vol 31 (1) ◽

pp. 61-74

Author(s):

G. Peaucellier ◽

P. Guerrier ◽

J. Bergerard

Keyword(s):

Cytochalasin B ◽

Polar Body ◽

Polar Lobe ◽

Developmental Abnormalities ◽

Drug Concentrations ◽

Internal Mechanism ◽

Polar Body Extrusion

1. Unfertilized, fertilized and activated eggs of Sabellaria alveolata were submitted to cytochalasin B concentrations ranging from 0·1 to 20 μg/ml. Their behaviour was studied either in vivo or in acetocarmine squash preparations. 2. Polar body extrusion, cytokinesis and polar lobe formation are completely inhibited by cytochalasin B concentrations as low as 0·3–0·5 μg/ml. 3. Caryotype determinations demonstrate that chromosomal meiotic and mitotic processes are not affected by the drug. Thus, polyploid embryos usually developed from fertilized eggs whilst they did not from activated ones. This is related to the contrasting behaviour of meiotic and cleavage centres. While the latter duplicates at each cycle, the former cannot replicate at the end of meiosis. This leads to an abortive monastral stage even if inhibition of polar body extrusion has provided the egg with two or four centres. These observations suggest the existence of an internal mechanism regulating the number of effective centrioles at the end of meiosis. They demonstrate also that the main cause of developmental failure in activated eggs cannot be related to ploidy. 4. Eggs treated throughout meiosis with moderate drug concentrations developed into swimming larvae. However, frequent developmental abnormalities affecting lobe dependent structures were obtained even if polar lobe formation was unimpaired. This suggests either that cytochalasin B has irreversibly affected some decisive cortical element or that previously described activating processes, which begin with polar lobe formation, are actually exerted on specific materials segregated during meiosis.

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