1
|
Xiao W, Akao S, Okamoto R, Otsuki J. The formation of aggregated chromatin/chromosomes in mouse oocytes treated with high concentration of IBMX as a model for a chromosome transfer in human. Syst Biol Reprod Med 2024; 70:195-203. [PMID: 38972054 DOI: 10.1080/19396368.2024.2368116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/25/2024] [Accepted: 06/10/2024] [Indexed: 07/09/2024]
Abstract
The presence of cyclic adenosine monophosphate (cAMP) has been considered to be a fundamental factor in ensuring meiotic arrest prior to ovulation. cAMP is regarded as a key molecule in the regulation of oocyte maturation. However, it has been reported that increased levels of intracellular cAMP can result in abnormal cytokinesis, with some MI oocytes leading to symmetrically cleaved 2-cell MII oocytes. Consequently, we aimed to investigate the effects of elevated intracellular cAMP levels on abnormal cytokinesis and oocyte maturation during the meiosis of mouse oocytes. This study found that a high concentration of isobutylmethylxanthine (IBMX) also caused chromatin/chromosomes aggregation (AC) after the first meiosis. The rates of AC increased the greater the concentration of IBMX. In addition, AC formation was found to be reversible, showing that the re-formation of the spindle chromosome complex was possible after the IBMX was removed. In human oocytes, the chromosomes aggregate after the germinal vesicle breakdown and following the first and second polar body extrusions (the AC phase), while mouse oocytes do not have this AC phase. The results of our current study may indicate that the AC phase in human oocytes could be related to elevated levels of intracytoplasmic cAMP.
Collapse
Affiliation(s)
- Wei Xiao
- Graduate School of Environmental, Life, Natural Science and Technology, Okayama University, Kita, Okayama, Japan
| | - Sakura Akao
- Faculty of Agriculture, Department of Animal Sciences, Okayama University, Kita, Okayama, Japan
| | - Ryota Okamoto
- Department of Obstetrics and Gynecology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Kita, Okayama, Japan
| | - Junko Otsuki
- Graduate School of Environmental, Life, Natural Science and Technology, Okayama University, Kita, Okayama, Japan
- Assisted Reproductive Technology Center, Okayama University, Kita, Okayama, Japan
| |
Collapse
|
2
|
Ma C, Xu Y, Chen H, Huang Y, Wang S, Zhang P, Li G, Xu Z, Xu X, Ding Z, Xiang H, Cao Y. Bisphenol Z exposure inhibits oocyte meiotic maturation by rupturing mitochondrial function. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2024; 276:116312. [PMID: 38608383 DOI: 10.1016/j.ecoenv.2024.116312] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2024] [Revised: 04/01/2024] [Accepted: 04/08/2024] [Indexed: 04/14/2024]
Abstract
The use of bisphenol A (BPA) has been restricted due to its endocrine-disrupting effects. As a widely used alternative to BPA today, environmental levels of bisphenol Z (BPZ) continue to rise and accumulate in humans. Oocyte quality is critical for a successful pregnancy. Nevertheless, the toxic impacts of BPZ on the maturation of mammalian oocytes remain unexplored. Therefore, the impacts of BPZ and BPA on oocyte meiotic maturation were compared in an in vitro mouse oocyte culture model. Exposure to 150 μM of both BPZ and BPA disrupted the assembly of the meiotic spindle and the alignment of chromosomes, and BPZ exerted stronger toxicological effects than BPA. Furthermore, BPZ resulted in aberrant expression of F-actin, preventing the formation of the actin cap. Mechanistically, BPZ exposure disrupted the mitochondrial localization pattern, reduced mitochondrial membrane potential and ATP content, leading to impaired mitochondrial function. Further studies revealed that BPZ exposure resulted in oxidative stress and altered expression of genes associated with anti-oxidative stress. Moreover, BPZ induced severe DNA damage and triggered early apoptosis in oocytes, accompanied by impaired lysosomal function. Overall, the data in this study suggest that BPZ is not a safe alternative to BPA. BPZ can trigger early apoptosis by affecting mitochondrial function and causing oxidative stress and DNA damage in oocytes. These processes disrupt cytoskeletal assembly, arrest the cell cycle, and ultimately inhibit oocyte meiotic maturation.
Collapse
Affiliation(s)
- Cong Ma
- Reproductive Medicine Center, Department of Obstetrics and Gynecology, The First Affiliated Hospital of Anhui Medical University, No.218 Jixi Road, Hefei 230022, China; NHC Key Laboratory of Study on Abnormal Gametes and Reproductive Tract, Anhui Medical University, No.81 Meishan Road, Hefei 230032, China; Key Laboratory of Population Health Across Life Cycle, Anhui Medical University, Ministry of Education of the People's Republic of China, No.81 Meishan Road, Hefei 230032, China
| | - Yan Xu
- Reproductive Medicine Center, Department of Obstetrics and Gynecology, The First Affiliated Hospital of Anhui Medical University, No.218 Jixi Road, Hefei 230022, China; NHC Key Laboratory of Study on Abnormal Gametes and Reproductive Tract, Anhui Medical University, No.81 Meishan Road, Hefei 230032, China; Key Laboratory of Population Health Across Life Cycle, Anhui Medical University, Ministry of Education of the People's Republic of China, No.81 Meishan Road, Hefei 230032, China
| | - Huilei Chen
- Reproductive Medicine Center, Department of Obstetrics and Gynecology, The First Affiliated Hospital of Anhui Medical University, No.218 Jixi Road, Hefei 230022, China; NHC Key Laboratory of Study on Abnormal Gametes and Reproductive Tract, Anhui Medical University, No.81 Meishan Road, Hefei 230032, China; Key Laboratory of Population Health Across Life Cycle, Anhui Medical University, Ministry of Education of the People's Republic of China, No.81 Meishan Road, Hefei 230032, China
| | - Yue Huang
- Reproductive Medicine Center, Department of Obstetrics and Gynecology, The First Affiliated Hospital of Anhui Medical University, No.218 Jixi Road, Hefei 230022, China
| | - Shanshan Wang
- Reproductive Medicine Center, Department of Obstetrics and Gynecology, The First Affiliated Hospital of Anhui Medical University, No.218 Jixi Road, Hefei 230022, China
| | - Pin Zhang
- Reproductive Medicine Center, Department of Obstetrics and Gynecology, The First Affiliated Hospital of Anhui Medical University, No.218 Jixi Road, Hefei 230022, China
| | - Guojing Li
- Reproductive Medicine Center, Department of Obstetrics and Gynecology, The First Affiliated Hospital of Anhui Medical University, No.218 Jixi Road, Hefei 230022, China
| | - Zuying Xu
- Reproductive Medicine Center, Department of Obstetrics and Gynecology, The First Affiliated Hospital of Anhui Medical University, No.218 Jixi Road, Hefei 230022, China; NHC Key Laboratory of Study on Abnormal Gametes and Reproductive Tract, Anhui Medical University, No.81 Meishan Road, Hefei 230032, China; Key Laboratory of Population Health Across Life Cycle, Anhui Medical University, Ministry of Education of the People's Republic of China, No.81 Meishan Road, Hefei 230032, China
| | - Xiaofeng Xu
- Reproductive Medicine Center, Department of Obstetrics and Gynecology, The First Affiliated Hospital of Anhui Medical University, No.218 Jixi Road, Hefei 230022, China; NHC Key Laboratory of Study on Abnormal Gametes and Reproductive Tract, Anhui Medical University, No.81 Meishan Road, Hefei 230032, China; Key Laboratory of Population Health Across Life Cycle, Anhui Medical University, Ministry of Education of the People's Republic of China, No.81 Meishan Road, Hefei 230032, China
| | - Zhiming Ding
- NHC Key Laboratory of Study on Abnormal Gametes and Reproductive Tract, Anhui Medical University, No.81 Meishan Road, Hefei 230032, China; Key Laboratory of Population Health Across Life Cycle, Anhui Medical University, Ministry of Education of the People's Republic of China, No.81 Meishan Road, Hefei 230032, China.
| | - Huifen Xiang
- Reproductive Medicine Center, Department of Obstetrics and Gynecology, The First Affiliated Hospital of Anhui Medical University, No.218 Jixi Road, Hefei 230022, China; NHC Key Laboratory of Study on Abnormal Gametes and Reproductive Tract, Anhui Medical University, No.81 Meishan Road, Hefei 230032, China; Key Laboratory of Population Health Across Life Cycle, Anhui Medical University, Ministry of Education of the People's Republic of China, No.81 Meishan Road, Hefei 230032, China.
| | - Yunxia Cao
- Reproductive Medicine Center, Department of Obstetrics and Gynecology, The First Affiliated Hospital of Anhui Medical University, No.218 Jixi Road, Hefei 230022, China; NHC Key Laboratory of Study on Abnormal Gametes and Reproductive Tract, Anhui Medical University, No.81 Meishan Road, Hefei 230032, China; Key Laboratory of Population Health Across Life Cycle, Anhui Medical University, Ministry of Education of the People's Republic of China, No.81 Meishan Road, Hefei 230032, China; Engineering Research Center of Biopreservation and Artificial Organs, Ministry of Education, No.81 Meishan Road, Hefei, Anhui 230032, China; Anhui Province Key Laboratory of Reproductive Health and Genetics, No.81 Meishan Road, Hefei 230032, China; Biopreservation and Artificial Organs, Anhui Provincial Engineering Research Center, Anhui Medical University, No.81 Meishan Road, Hefei 230032, China; Anhui Provincial Institute of Translational Medicine, No.81 Meishan Road, Hefei 230032, China.
| |
Collapse
|
3
|
Verbič A, Lebar T, Praznik A, Jerala R. Subunits of an E3 Ligase Complex as Degrons for Efficient Degradation of Cytosolic, Nuclear, and Membrane Proteins. ACS Synth Biol 2024; 13:792-803. [PMID: 38404221 PMCID: PMC10949250 DOI: 10.1021/acssynbio.3c00588] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Revised: 02/09/2024] [Accepted: 02/13/2024] [Indexed: 02/27/2024]
Abstract
Protein degradation is a highly regulated cellular process crucial to enable the high dynamic range of the response to external and internal stimuli and to balance protein biosynthesis to maintain cell homeostasis. Within mammalian cells, hundreds of E3 ubiquitin ligases target specific protein substrates and could be repurposed for synthetic biology. Here, we present a systematic analysis of the four protein subunits of the multiprotein E3 ligase complex as scaffolds for the designed degrons. While all of them were functional, the fusion of a fragment of Skp1 with the target protein enabled the most effective degradation. Combination with heterodimerizing peptides, protease substrate sites, and chemically inducible dimerizers enabled the regulation of protein degradation. While the investigated subunits of E3 ligases showed variable degradation efficiency of the membrane and cytosolic and nuclear proteins, the bipartite SSD (SOCSbox-Skp1(ΔC111)) degron enabled fast degradation of protein targets in all tested cellular compartments, including the nucleus and plasma membrane, in different cell lines and could be chemically regulated. These subunits could be employed for research as well as for diverse applications, as demonstrated in the regulation of Cas9 and chimeric antigen receptor proteins.
Collapse
Affiliation(s)
- Anže Verbič
- Department of Synthetic Biology
and Immunology, National Institute of Chemistry, Ljubljana 1000, Slovenia
| | | | - Arne Praznik
- Department of Synthetic Biology
and Immunology, National Institute of Chemistry, Ljubljana 1000, Slovenia
| | - Roman Jerala
- Department of Synthetic Biology
and Immunology, National Institute of Chemistry, Ljubljana 1000, Slovenia
| |
Collapse
|
4
|
Owen CM, Jaffe LA. Luteinizing hormone stimulates ingression of mural granulosa cells within the mouse preovulatory follicle†. Biol Reprod 2024; 110:288-299. [PMID: 37847612 PMCID: PMC10873281 DOI: 10.1093/biolre/ioad142] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Revised: 09/25/2023] [Accepted: 10/13/2023] [Indexed: 10/19/2023] Open
Abstract
Luteinizing hormone (LH) induces ovulation by acting on its receptors in the mural granulosa cells that surround a mammalian oocyte in an ovarian follicle. However, much remains unknown about how activation of the LH receptor modifies the structure of the follicle such that the oocyte is released and the follicle remnants are transformed into the corpus luteum. The present study shows that the preovulatory surge of LH stimulates LH receptor-expressing granulosa cells, initially located almost entirely in the outer layers of the mural granulosa, to rapidly extend inwards, intercalating between other cells. The cellular ingression begins within 30 min of the peak of the LH surge, and the proportion of LH receptor-expressing cell bodies in the inner half of the mural granulosa layer increases until the time of ovulation, which occurs at about 10 h after the LH peak. During this time, many of the initially flask-shaped cells appear to detach from the basal lamina, acquiring a rounder shape with multiple filipodia. Starting at about 4 h after the LH peak, the mural granulosa layer at the apical surface of the follicle where ovulation will occur begins to thin, and the basolateral surface develops invaginations and constrictions. Our findings raise the question of whether LH stimulation of granulosa cell ingression may contribute to these changes in the follicular structure that enable ovulation.
Collapse
Affiliation(s)
- Corie M Owen
- Department of Cell Biology, University of Connecticut Health Center, Farmington, CT, USA
| | - Laurinda A Jaffe
- Department of Cell Biology, University of Connecticut Health Center, Farmington, CT, USA
| |
Collapse
|
5
|
Horakova A, Konecna M, Anger M. Chromosome Division in Early Embryos-Is Everything under Control? And Is the Cell Size Important? Int J Mol Sci 2024; 25:2101. [PMID: 38396778 PMCID: PMC10889803 DOI: 10.3390/ijms25042101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2023] [Revised: 02/02/2024] [Accepted: 02/06/2024] [Indexed: 02/25/2024] Open
Abstract
Chromosome segregation in female germ cells and early embryonic blastomeres is known to be highly prone to errors. The resulting aneuploidy is therefore the most frequent cause of termination of early development and embryo loss in mammals. And in specific cases, when the aneuploidy is actually compatible with embryonic and fetal development, it leads to severe developmental disorders. The main surveillance mechanism, which is essential for the fidelity of chromosome segregation, is the Spindle Assembly Checkpoint (SAC). And although all eukaryotic cells carry genes required for SAC, it is not clear whether this pathway is active in all cell types, including blastomeres of early embryos. In this review, we will summarize and discuss the recent progress in our understanding of the mechanisms controlling chromosome segregation and how they might work in embryos and mammalian embryos in particular. Our conclusion from the current literature is that the early mammalian embryos show limited capabilities to react to chromosome segregation defects, which might, at least partially, explain the widespread problem of aneuploidy during the early development in mammals.
Collapse
Affiliation(s)
- Adela Horakova
- Department of Genetics and Reproductive Biotechnologies, Veterinary Research Institute, 621 00 Brno, Czech Republic
- Institute of Animal Physiology and Genetics, Czech Academy of Science, 277 21 Libechov, Czech Republic
- Faculty of Science, Masaryk University, 602 00 Brno, Czech Republic
| | - Marketa Konecna
- Department of Genetics and Reproductive Biotechnologies, Veterinary Research Institute, 621 00 Brno, Czech Republic
- Institute of Animal Physiology and Genetics, Czech Academy of Science, 277 21 Libechov, Czech Republic
- Faculty of Science, Masaryk University, 602 00 Brno, Czech Republic
| | - Martin Anger
- Department of Genetics and Reproductive Biotechnologies, Veterinary Research Institute, 621 00 Brno, Czech Republic
- Institute of Animal Physiology and Genetics, Czech Academy of Science, 277 21 Libechov, Czech Republic
| |
Collapse
|
6
|
Kordowitzki P, Graczyk S, Haghani A, Klutstein M. Oocyte Aging: A Multifactorial Phenomenon in A Unique Cell. Aging Dis 2024; 15:5-21. [PMID: 37307833 PMCID: PMC10796106 DOI: 10.14336/ad.2023.0527] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2023] [Accepted: 05/27/2023] [Indexed: 06/14/2023] Open
Abstract
The oocyte is considered to be the largest cell in mammalian species. Women hoping to become pregnant face a ticking biological clock. This is becoming increasingly challenging as an increase in life expectancy is accompanied by the tendency to conceive at older ages. With advancing maternal age, the fertilized egg will exhibit lower quality and developmental competence, which contributes to increased chances of miscarriage due to several causes such as aneuploidy, oxidative stress, epigenetics, or metabolic disorders. In particular, heterochromatin in oocytes and with it, the DNA methylation landscape undergoes changes. Further, obesity is a well-known and ever-increasing global problem as it is associated with several metabolic disorders. More importantly, both obesity and aging negatively affect female reproduction. However, among women, there is immense variability in age-related decline of oocytes' quantity, developmental competence, or quality. Herein, the relevance of obesity and DNA-methylation will be discussed as these aspects have a tremendous effect on female fertility, and it is a topic of continuous and widespread interest that has yet to be fully addressed for the mammalian oocyte.
Collapse
Affiliation(s)
- Pawel Kordowitzki
- Department of Preclinical and Basic Sciences, Faculty of Biological and Veterinary Sciences, Nicolaus Copernicus University, Torun, Poland.
| | - Szymon Graczyk
- Department of Preclinical and Basic Sciences, Faculty of Biological and Veterinary Sciences, Nicolaus Copernicus University, Torun, Poland.
| | - Amin Haghani
- Department of Human Genetics, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, USA.
- Altos Labs, San Diego, CA, USA.
| | - Michael Klutstein
- Institute of Biomedical and Oral Research, Hebrew University of Jerusalem, Jerusalem, Israel
| |
Collapse
|
7
|
Fair T, Lonergan P. The oocyte: the key player in the success of assisted reproduction technologies. Reprod Fertil Dev 2023; 36:133-148. [PMID: 38064189 DOI: 10.1071/rd23164] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2023] Open
Abstract
The ovulation of a mature oocyte at metaphase II of meiosis, with optimal potential to undergo fertilisation by a sperm cell, complete meiosis and sustain the switch to mitotic division, and support early embryo development, involves a protracted and disrupted/delayed series of processes. Many of these are targeted for exploitation in vivo , or recapitulation in vitro , by the livestock industry. Reproductive technologies, including AI, multiple ovulation embryo transfer, ovum pick-up, in vitro embryo production, and oestrus and ovulation synchronisation, offer practitioners and producers the opportunity to produce offspring from genetically valuable dams in much greater numbers than they would normally have in their lifetime, while in vitro oocyte and follicle culture are important platforms for researchers to interrogate the physiological mechanisms driving fertility. The majority of these technologies target the ovarian follicle and the oocyte within; thus, the quality and capability of the recovered oocyte determine the success of the reproductive intervention. Molecular and microscopical technologies have grown exponentially, providing powerful platforms to interrogate the molecular mechanisms which are integral to or affected by ART. The development of the bovine oocyte from its differentiation in the ovary to ovulation is described in the light of its relevance to key aspects of individual interventions, while highlighting the historical timeline.
Collapse
Affiliation(s)
- Trudee Fair
- School of Agriculture and Food Science, University College Dublin, Belfield, Dublin, Ireland
| | - Pat Lonergan
- School of Agriculture and Food Science, University College Dublin, Belfield, Dublin, Ireland
| |
Collapse
|
8
|
Okamoto R, Xiao W, Fukasawa H, Hirata S, Sankai T, Masuyama H, Otsuki J. Aggregated chromosomes/chromatin transfer: a novel approach for mitochondrial replacement with minimal mitochondrial carryover: the implications of mouse experiments for human aggregated chromosome transfer. Mol Hum Reprod 2023; 29:gaad043. [PMID: 38039159 DOI: 10.1093/molehr/gaad043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Revised: 11/01/2023] [Indexed: 12/03/2023] Open
Abstract
Nuclear transfer techniques, including spindle chromosome complex (SC) transfer and pronuclear transfer, have been employed to mitigate mitochondrial diseases. Nevertheless, the challenge of mitochondrial DNA (mtDNA) carryover remains unresolved. Previously, we introduced a method for aggregated chromosome (AC) transfer in human subjects, offering a potential solution. However, the subsequent rates of embryonic development have remained unexplored owing to legal limitations in Japan, and animal studies have been hindered by a lack of AC formation in other species. Building upon our success in generating ACs within mouse oocytes via utilization of the phosphodiesterase inhibitor 3-isobutyl 1-methylxanthine (IBMX), this study has established a mouse model for AC transfer. Subsequently, a comparative analysis of embryo development rates and mtDNA carryover between AC transfer and SC transfer was conducted. Additionally, the mitochondrial distribution around SC and AC structures was investigated, revealing that in oocytes at the metaphase II stage, the mitochondria exhibited a relatively concentrated arrangement around the spindle apparatus, while the distribution of mitochondria in AC-formed oocytes appeared to be independent of the AC position. The AC transfer approach produced a marked augmentation in rates of fertilization, embryo cleavage, and blastocyst formation, especially as compared to scenarios without AC transfer in IBMX-treated AC-formed oocytes. No significant disparities in fertilization and embryo development rates were observed between AC and SC transfers. However, relative real-time PCR analyses revealed that the mtDNA carryover for AC transfers was one-tenth and therefore significantly lower than that of SC transfers. This study successfully accomplished nuclear transfers with ACs in mouse oocytes, offering an insight into the potential of AC transfers as a solution to heteroplasmy-related challenges. These findings are promising in terms of future investigation with human oocytes, thus advancing AC transfer as an innovative approach in the field of human nuclear transfer methodology.
Collapse
Affiliation(s)
- R Okamoto
- Department of Obstetrics and Gynecology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Kita, Okayama, Japan
| | - W Xiao
- Department of Applied Animal Science, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University, Kita, Okayama, Japan
| | - H Fukasawa
- Department of Obstetrics and Gynecology, Faculty of Medicine, University of Yamanashi, Chuo, Yamanashi, Japan
| | - S Hirata
- Department of Obstetrics and Gynecology, Faculty of Medicine, University of Yamanashi, Chuo, Yamanashi, Japan
| | - T Sankai
- Tsukuba Primate Research Center, National Institutes of Biomedical Innovation, Health and Nutrition, Tsukuba, Ibaraki, Japan
| | - H Masuyama
- Department of Obstetrics and Gynecology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Kita, Okayama, Japan
| | - J Otsuki
- Department of Applied Animal Science, Graduate School of Environmental, Life, Natural Science and Technology, Okayama University, Kita, Okayama, Japan
- Assisted Reproductive Technology Center, Okayama University, Kita, Okayama, Japan
| |
Collapse
|
9
|
Asama H, Kamibayashi D, Hashizume A, Michikura Y, Otsuki J. Focusing on the accumulation of chromatin/chromosomes around nucleoli and optimizing the timing of ICSI to facilitate the rescue in vitro maturation of denuded GV stage oocytes. J Assist Reprod Genet 2023; 40:2557-2564. [PMID: 37725177 PMCID: PMC10643760 DOI: 10.1007/s10815-023-02921-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Accepted: 08/21/2023] [Indexed: 09/21/2023] Open
Abstract
PURPOSE This study aims to achieve the methodological improvement of rescue IVM by predicting germinal vesicle breakdown (GVBD) and optimizing the timing of ICSI. METHODS Time lapse analysis was performed retrospectively to evaluated the relationship between the presence of AC around the nucleoli and GVBD. To find the optimal timing of ICSI, the time from the initiation of the first polar body extrusion to ICSI were measured, and the rates of fertilization at each point were calculated. RESULTS The GVBD rate of GV stage oocytes with AC around the nucleoli was significantly higher than that of GV stage oocytes without AC. The GV stage oocytes required more time for nuclear maturation after polar body extrusion than MI oocytes, with GV stage oocytes taking 400-600 min from polar body extrusion to the optimal timing of ICSI, while the MI stage oocytes took 200-400 min. The GV stage oocytes resulted in the birth of healthy babies with the appropriate timing of ICSI. CONCLUSION It was found that GV stage oocytes with AC around nucleoli can initiate GVBD and reach the MII stage with a high rate, and that GV stage oocytes required more time than MI stage oocytes to reach the optimal timing of ICSI. Considering these factors, ART laboratories may employ immature GV stage oocytes in routine ART procedures rather than discarding them.
Collapse
Affiliation(s)
- Hayato Asama
- Graduate School of Environmental, Life, Natural Science and Technology, Okayama University, 1-1-1 Tsushimanaka, Kita, Okayama, 700-8530, Japan
- Kanazawa Tamago Clinic, 327-1 Nakachou, Moroemachi, Kanazawa, Ishikawa, 920-0016, Japan
| | - Daigaku Kamibayashi
- Kanazawa Tamago Clinic, 327-1 Nakachou, Moroemachi, Kanazawa, Ishikawa, 920-0016, Japan
| | - Atsuko Hashizume
- Kanazawa Tamago Clinic, 327-1 Nakachou, Moroemachi, Kanazawa, Ishikawa, 920-0016, Japan
| | - Yasuhito Michikura
- Kanazawa Tamago Clinic, 327-1 Nakachou, Moroemachi, Kanazawa, Ishikawa, 920-0016, Japan
| | - Junko Otsuki
- Graduate School of Environmental, Life, Natural Science and Technology, Okayama University, 1-1-1 Tsushimanaka, Kita, Okayama, 700-8530, Japan.
- Assisted Reproductive Technology Center, Okayama University, 1-1-1 Tsushimanaka, Kita, Okayama, 700-8530, Japan.
| |
Collapse
|
10
|
Pan MH, Xu R, Zheng Z, Xiong J, Dong H, Wei Q, Ma B. The formins inhibitor SMIFH2 inhibits the cytoskeleton dynamics and mitochondrial function during goat oocyte maturation. Theriogenology 2023; 211:40-48. [PMID: 37562190 DOI: 10.1016/j.theriogenology.2023.08.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2023] [Revised: 08/01/2023] [Accepted: 08/03/2023] [Indexed: 08/12/2023]
Abstract
The cytoskeleton plays a crucial role in facilitating the successful completion of the meiotic maturation of oocytes. Its influence extends to the process of oocyte nuclear maturation and the proper functioning of various organelles during cytoplasmic maturation. The formin family of proteins plays a crucial role in the molecular regulation of cytoskeletal assembly and organization; however, its role in goat oocytes are not fully understood. Our study examined the inhibition of formins activity, which revealed its crucial role in the maturation of goat oocytes. We observed that the inhibition of formins resulted in meiotic defects in goat oocytes, as evidenced by the hindered extrusion of polar bodies and the expansion of cumulus cells. Additionally, the oocytes exhibited altered actin dynamics and compromised spindle/chromosome structure upon formins inhibition. The results of the transcriptomic analysis highlighted a noteworthy alteration in the mRNA levels of genes implicated in mitochondrial functions and oxidative phosphorylation in formins inhibited oocytes. Validation experiments provided evidence that the meiotic defects observed in these oocytes were due to the excessive early apoptosis induced by reactive oxygen species (ROS). Our findings demonstrate that the involvement of formins in sustaining the cytoskeletal dynamics and mitochondrial function is crucial for the successful meiotic maturation of goat oocytes.
Collapse
Affiliation(s)
- Meng-Hao Pan
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China; Key Laboratory of Animal Biotechnology, Ministry of Agriculture, Yangling, Shaanxi, China
| | - Rui Xu
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China; Key Laboratory of Animal Biotechnology, Ministry of Agriculture, Yangling, Shaanxi, China
| | - Zhi Zheng
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China; Key Laboratory of Animal Biotechnology, Ministry of Agriculture, Yangling, Shaanxi, China
| | - Jinfeng Xiong
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China; Key Laboratory of Animal Biotechnology, Ministry of Agriculture, Yangling, Shaanxi, China
| | - Haiying Dong
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China; Key Laboratory of Animal Biotechnology, Ministry of Agriculture, Yangling, Shaanxi, China
| | - Qiang Wei
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China; Key Laboratory of Animal Biotechnology, Ministry of Agriculture, Yangling, Shaanxi, China
| | - Baohua Ma
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China; Key Laboratory of Animal Biotechnology, Ministry of Agriculture, Yangling, Shaanxi, China.
| |
Collapse
|
11
|
Owen CM, Jaffe LA. Luteinizing hormone stimulates ingression of mural granulosa cells within the mouse preovulatory follicle. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.04.21.537855. [PMID: 37131774 PMCID: PMC10153244 DOI: 10.1101/2023.04.21.537855] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Luteinizing hormone (LH) induces ovulation by acting on its receptors in the mural granulosa cells that surround a mammalian oocyte in an ovarian follicle. However, much remains unknown about how activation of the LH receptor modifies the structure of the follicle such that the oocyte is released and the follicle remnants are transformed into the corpus luteum. The present study shows that the preovulatory surge of LH stimulates LH receptor-expressing granulosa cells, initially located almost entirely in the outer layers of the mural granulosa, to rapidly extend inwards, intercalating between other cells. The cellular ingression begins within 30 minutes of the peak of the LH surge, and the proportion of LH receptor-expressing cell bodies in the inner half of the mural granulosa layer increases until the time of ovulation, which occurs at about 10 hours after the LH peak. During this time, many of the initially flask-shaped cells appear to detach from the basal lamina, acquiring a rounder shape with multiple filipodia. Starting at about 4 hours after the LH peak, the mural granulosa layer at the apical surface of the follicle where ovulation will occur begins to thin, and the basolateral surface develops invaginations and constrictions. Our findings raise the question of whether LH stimulation of granulosa cell ingression may contribute to these changes in the follicular structure that enable ovulation.
Collapse
Affiliation(s)
- Corie M. Owen
- Department of Cell Biology, University of Connecticut Health Center, Farmington, CT 06030 USA
| | - Laurinda A. Jaffe
- Department of Cell Biology, University of Connecticut Health Center, Farmington, CT 06030 USA
| |
Collapse
|
12
|
Quiogue AR, Sumiyoshi E, Fries A, Chuang CH, Bowerman B. Cortical microtubules oppose actomyosin-driven membrane ingression during C. elegans meiosis I polar body extrusion. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.26.542508. [PMID: 37292632 PMCID: PMC10245968 DOI: 10.1101/2023.05.26.542508] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
During C. elegans oocyte meiosis I, cortical actomyosin is locally remodeled to assemble a contractile ring near the spindle. In contrast to mitosis, when most cortical actomyosin converges into a contractile ring, the small oocyte ring forms within and remains part of a much larger and actively contractile cortical actomyosin network. This network both mediates contractile ring dynamics and generates shallow ingressions throughout the oocyte cortex during polar body extrusion. Based on our analysis of requirements for CLS-2, a member of the CLASP family of proteins that stabilize microtubules, we recently proposed that a balance of actomyosin-mediated tension and microtubule-mediated stiffness are required for contractile ring assembly within the oocyte cortical actomyosin network. Here, using live cell imaging and fluorescent protein fusions, we show that CLS-2 is part of a complex of kinetochore proteins, including the scaffold KNL-1 and the kinase BUB-1, that also co-localize to patches distributed throughout the oocyte cortex during meiosis I. By reducing their function, we further show that KNL-1 and BUB-1, like CLS-2, are required for cortical microtubule stability, to limit membrane ingression throughout the oocyte, and for meiotic contractile ring assembly and polar body extrusion. Moreover, nocodazole or taxol treatment to destabilize or stabilize oocyte microtubules, respectively, leads to excess or decreased membrane ingression throughout the oocyte and defective polar body extrusion. Finally, genetic backgrounds that elevate cortical microtubule levels suppress the excess membrane ingression in cls-2 mutant oocytes. These results support our hypothesis that CLS-2, as part of a sub-complex of kinetochore proteins that also co-localize to patches throughout the oocyte cortex, stabilizes microtubules to stiffen the oocyte cortex and limit membrane ingression throughout the oocyte, thereby facilitating contractile ring dynamics and the successful completion of polar body extrusion during meiosis I.
Collapse
Affiliation(s)
| | | | - Adam Fries
- Institute of Molecular Biology
- Imaging Core, Office of the Vice President for Research, University of Oregon, Eugene, OR USA 97403
| | | | | |
Collapse
|
13
|
Nikalayevich E, Terret ME. Meiosis: Actin and microtubule networks drive chromosome clustering in oocytes. Curr Biol 2023; 33:R272-R274. [PMID: 37040710 DOI: 10.1016/j.cub.2023.02.061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/13/2023]
Abstract
Actin and microtubule networks in human and porcine oocytes sequentially gather chromosomes in a cluster shortly after nuclear envelope breakdown to ensure their complete capture by the meiotic spindle.
Collapse
Affiliation(s)
- Elvira Nikalayevich
- Center for Interdisciplinary Research in Biology (CIRB), Collège de France, CNRS, INSERM, Université PSL, Paris, France.
| | - Marie-Emilie Terret
- Center for Interdisciplinary Research in Biology (CIRB), Collège de France, CNRS, INSERM, Université PSL, Paris, France
| |
Collapse
|