1
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Szasz-Green T, Shores K, Vanga V, Zacharias L, Lawton AK, Dapper AL. Comparative Phylogenetics Reveal Clade-specific Drivers of Recombination Rate Evolution Across Vertebrates. Mol Biol Evol 2025; 42:msaf100. [PMID: 40331240 PMCID: PMC12100477 DOI: 10.1093/molbev/msaf100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2024] [Revised: 03/06/2025] [Accepted: 04/11/2025] [Indexed: 05/08/2025] Open
Abstract
Meiotic recombination is an integral cellular process, required for the production of viable gametes. Recombination rate is a fundamental genomic parameter, modulating genomic responses to selection. Our increasingly detailed understanding of its molecular underpinnings raises the prospect that we can gain insight into trait divergence by examining the molecular evolution of recombination genes from a pathway perspective, as in mammals, where protein-coding changes in later stages of the recombination pathway are connected to divergence in intra-clade recombination rate. Here, we leverage increased availability of avian and teleost genomes to reconstruct the evolution of the recombination pathway across two additional vertebrate clades: birds, which have higher and more variable rates of recombination and similar divergence times to mammals, and teleost fish, which have much deeper divergence times. Rates of molecular evolution of recombination genes are highly correlated between vertebrate clades and significantly elevated compared to control panels, suggesting that they experience similar selective pressures. Avian recombination genes are significantly more likely to exhibit signatures of positive selection than other clades, unrestricted to later stages of the pathway. Signatures of positive selection in genes linked to recombination rate variation in mammalian populations and those with signatures of positive selection across the avian phylogeny are highly correlated. In contrast, teleost fish recombination genes have significantly less evidence of positive selection despite high intra-clade recombination rate variability. Gaining clade-specific understanding of patterns of variation in recombination genes can elucidate drivers of recombination rate and thus, factors influencing genetic diversity, selection efficacy, and species divergence.
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Affiliation(s)
- Taylor Szasz-Green
- Department of Biological Sciences, Mississippi State University, Mississippi State, MS 39762, USA
| | - Katherynne Shores
- Department of Biological Sciences, Mississippi State University, Mississippi State, MS 39762, USA
| | - Vineel Vanga
- Department of Biological Sciences, Mississippi State University, Mississippi State, MS 39762, USA
| | - Luke Zacharias
- Department of Biological Sciences, Mississippi State University, Mississippi State, MS 39762, USA
| | - Andrew K Lawton
- Department of Biology, Appalachian State University, Boone, NC 28608, USA
| | - Amy L Dapper
- Department of Biological Sciences, Mississippi State University, Mississippi State, MS 39762, USA
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2
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Gomes Paim LM, Bechstedt S. Regulation of microtubule growth rates and their impact on chromosomal instability. Cell Cycle 2025:1-20. [PMID: 40260826 DOI: 10.1080/15384101.2025.2485842] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2024] [Revised: 01/15/2025] [Accepted: 01/16/2025] [Indexed: 04/24/2025] Open
Abstract
Microtubules are polymers of α/β tubulin dimers that build the mitotic spindle, which segregates duplicated chromosomes during cell division. Microtubule function is governed by dynamic instability, whereby cycles of growth and shrinkage contribute to the forces necessary for chromosome movement. Regulation of microtubule growth velocity requires cell cycle-dependent changes in expression, localization and activity of microtubule-associated proteins (MAPs) as well as tubulin post-translational modifications that modulate microtubule dynamics. It has become clear that optimal microtubule growth velocities are required for proper chromosome segregation and ploidy maintenance. Suboptimal microtubule growth rates can result from altered activity of MAPs and could lead to aneuploidy, possibly by disrupting the establishment of microtubule bundles at kinetochores and altering the mechanical forces required for sister chromatid segregation. Future work using high-resolution, low-phototoxicity microscopy and novel fluorescent markers will be invaluable in obtaining deeper mechanistic insights into how microtubule processes contribute to chromosome segregation.
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Affiliation(s)
| | - Susanne Bechstedt
- Department of Anatomy and Cell Biology, McGill University, Montréal, Canada
- Centre de Recherche en Biologie Structurale (CRBS), McGill University, Montréal, Canada
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3
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Zhu S, Xie P, Yang Y, Wang Y, Zhang C, Zhang Y, Si S, Zhang J, He J, Si H, Fang K, Ma B, Jiang X, Huang L, Li J, Min T, Zheng B, Da L, Lin D, Gao K, Li Y, Huang M, Qiao F, Huo H, Feng H, Zhao H, Chen Z, Xu Z, Xie J, Cao H, Liu J, Yao X, Xie W, Sun Y, Wu K, Xiong B, Hu P, Luo Z, Lin C. Maternal ELL3 loss-of-function leads to oocyte aneuploidy and early miscarriage. Nat Struct Mol Biol 2025; 32:381-392. [PMID: 39820605 DOI: 10.1038/s41594-024-01471-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2024] [Accepted: 12/09/2024] [Indexed: 01/19/2025]
Abstract
Up to an estimated 10% of women experience miscarriage in their lifetimes. Embryonic aneuploidy is a leading cause for miscarriage, infertility and congenital defects. Here we identify variants of ELL3, a gene encoding a transcription elongation factor, in couples who experienced consecutive early miscarriages due to embryonic aneuploidy. Maternal ELL3 knockout leads to mouse oocyte aneuploidy, subfertility and miscellaneous embryonic defects. Mechanistically, we find that ELL3 localizes to the spindle during meiosis, and that ELL3 depletion in both mouse and human oocytes increases the incidence of meiotic spindle abnormality. ELL3 coordinates with TPX2 to ensure the proper function of the microtubule motor KIF11. Live imaging analysis shows that ELL3 is paramount for promoting spindle assembly and driving chromosome movement. Together, our findings implicate maternal ELL3 deficiency in causing oocyte aneuploidy and early miscarriage.
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Affiliation(s)
- Shiqi Zhu
- Key Laboratory of Developmental Genes and Human Disease, School of Life Science and Technology, Southeast University, Nanjing, China
- Co-innovation Center of Neuroregeneration, Nantong University, Nantong, China
| | - Peng Xie
- School of Biological Science and Medical Engineering, Southeast University, Nanjing, China
| | - Yi Yang
- Key Laboratory of Developmental Genes and Human Disease, School of Life Science and Technology, Southeast University, Nanjing, China
| | - Yan Wang
- Department of Prenatal Diagnosis, Women's Hospital of Nanjing Medical University, Nanjing, China
| | - Chuanxin Zhang
- Center of Reproductive Medicine, Shandong University, Jinan, China
| | - Yu Zhang
- College of Animal Sciences, Zhejiang University, Hangzhou, China
| | - Shuhan Si
- Key Laboratory of Developmental Genes and Human Disease, School of Life Science and Technology, Southeast University, Nanjing, China
| | - Jin Zhang
- Key Laboratory of Developmental Genes and Human Disease, School of Life Science and Technology, Southeast University, Nanjing, China
| | - Jingjing He
- Key Laboratory of Developmental Genes and Human Disease, School of Life Science and Technology, Southeast University, Nanjing, China
| | - Hao Si
- Key Laboratory of Developmental Genes and Human Disease, School of Life Science and Technology, Southeast University, Nanjing, China
| | - Ke Fang
- Key Laboratory of Developmental Genes and Human Disease, School of Life Science and Technology, Southeast University, Nanjing, China
| | - Binbin Ma
- School of Life Science and Technology, Tongji University, Shanghai, China
| | - Xu Jiang
- Key Laboratory of Developmental Genes and Human Disease, School of Life Science and Technology, Southeast University, Nanjing, China
| | - Lindi Huang
- Key Laboratory of Developmental Genes and Human Disease, School of Life Science and Technology, Southeast University, Nanjing, China
| | - Jiamin Li
- Key Laboratory of Developmental Genes and Human Disease, School of Life Science and Technology, Southeast University, Nanjing, China
| | - Tian Min
- Key Laboratory of Developmental Genes and Human Disease, School of Life Science and Technology, Southeast University, Nanjing, China
| | - Beihong Zheng
- Center of Reproductive Medicine, Fujian Maternity and Child Health Hospital, Fujuan, China
| | - Lincui Da
- Center of Reproductive Medicine, Fujian Maternity and Child Health Hospital, Fujuan, China
| | - Dianliang Lin
- Center of Reproductive Medicine, Fujian Maternity and Child Health Hospital, Fujuan, China
| | - Kun Gao
- Key Laboratory of Developmental Genes and Human Disease, School of Life Science and Technology, Southeast University, Nanjing, China
| | - Yuanyuan Li
- School of Life Science and Technology, Tongji University, Shanghai, China
| | - Mingtao Huang
- Department of Prenatal Diagnosis, Women's Hospital of Nanjing Medical University, Nanjing, China
| | - Fengchang Qiao
- Department of Prenatal Diagnosis, Women's Hospital of Nanjing Medical University, Nanjing, China
| | - Haiqin Huo
- Department of Prenatal Diagnosis, Women's Hospital of Nanjing Medical University, Nanjing, China
| | - Haoyang Feng
- Department of Prenatal Diagnosis, Women's Hospital of Nanjing Medical University, Nanjing, China
| | - Han Zhao
- Center of Reproductive Medicine, Shandong University, Jinan, China
| | - Zijiang Chen
- Center of Reproductive Medicine, Shandong University, Jinan, China
| | - Zhengfeng Xu
- Department of Prenatal Diagnosis, Women's Hospital of Nanjing Medical University, Nanjing, China
| | - Jing Xie
- School of Life Science and Technology, Tongji University, Shanghai, China
| | - Hua Cao
- Center of Reproductive Medicine, Fujian Maternity and Child Health Hospital, Fujuan, China
| | - Jin Liu
- School of Data Science, The Chinese University of Hong Kong, Shenzhen, China
| | - Xuebiao Yao
- Laboratory for Organelle Dynamics and Plasticity Control, School of Life Sciences, University of Science and Technology of China, Hefei, China
| | - Wei Xie
- Key Laboratory of Developmental Genes and Human Disease, School of Life Science and Technology, Southeast University, Nanjing, China
| | - Yan Sun
- Center of Reproductive Medicine, Fujian Maternity and Child Health Hospital, Fujuan, China.
| | - Keliang Wu
- Center of Reproductive Medicine, Shandong University, Jinan, China.
| | - Bo Xiong
- College of Animal Sciences, Zhejiang University, Hangzhou, China.
| | - Ping Hu
- Department of Prenatal Diagnosis, Women's Hospital of Nanjing Medical University, Nanjing, China.
| | - Zhuojuan Luo
- Key Laboratory of Developmental Genes and Human Disease, School of Life Science and Technology, Southeast University, Nanjing, China.
- Co-innovation Center of Neuroregeneration, Nantong University, Nantong, China.
- Shenzhen Research Institute, Southeast University, Shenzhen, China.
| | - Chengqi Lin
- Key Laboratory of Developmental Genes and Human Disease, School of Life Science and Technology, Southeast University, Nanjing, China.
- Co-innovation Center of Neuroregeneration, Nantong University, Nantong, China.
- Jiangsu Provincial Key Laboratory of Critical Care Medicine, School of Life Science and Technology, Southeast University, Nanjing, China.
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4
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Vasilev F, Mihajlović AI, Rémillard-Labrosse G, FitzHarris G. Long-lived cytokinetic bridges coordinate sister-cell elimination in mouse embryos. Dev Cell 2025:S1534-5807(25)00002-4. [PMID: 39862857 DOI: 10.1016/j.devcel.2025.01.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2024] [Revised: 08/14/2024] [Accepted: 01/03/2025] [Indexed: 01/27/2025]
Abstract
Apoptosis is a key feature of preimplantation development, but whether it occurs in a cell-autonomous or coordinated manner was unknown. Here, we report that plasma membrane abscission, the final step of cell division, is profoundly delayed in early mouse embryos such that a cytokinetic bridge is maintained for the vast majority of the following interphase. Early embryos thus consist of many pairs of sister cells connected by stable cytokinetic bridges that allow them to share diffusible molecules. We show that apoptotic regulators are shared through cytokinetic bridges and that these bridges ensure that if one cell enters apoptosis, its sister cell does as well. Long-lived cytokinetic bridges are thus a previously unappreciated form of cell-cell communication within the mouse embryo that coordinate the clearance of pairs of cells with similar developmental histories.
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Affiliation(s)
- Filip Vasilev
- Centre de recherche du Centre Hospitalier de I'Université de Montréal (CRCHUM), Montréal, QC H2X 0A9, Canada
| | - Aleksandar I Mihajlović
- Centre de recherche du Centre Hospitalier de I'Université de Montréal (CRCHUM), Montréal, QC H2X 0A9, Canada
| | | | - Greg FitzHarris
- Centre de recherche du Centre Hospitalier de I'Université de Montréal (CRCHUM), Montréal, QC H2X 0A9, Canada; Department of Obstetrics and Gynaecology, and Department of Pathology and Cell Biology, Université de Montréal, Montréal, QC H3T 1C5, Canada.
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5
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Yang Q, Wijaya F, Kapoor R, Chandrasekaran H, Jagtiani S, Moran I, Hime GR. Unusual modes of cell and nuclear divisions characterise Drosophila development. Biochem Soc Trans 2024; 52:2281-2295. [PMID: 39508395 PMCID: PMC11668308 DOI: 10.1042/bst20231341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2024] [Revised: 10/03/2024] [Accepted: 10/07/2024] [Indexed: 11/15/2024]
Abstract
The growth and development of metazoan organisms is dependent upon a co-ordinated programme of cellular proliferation and differentiation, from the initial formation of the zygote through to maintenance of mature organs in adult organisms. Early studies of proliferation of ex vivo cultures and unicellular eukaryotes described a cyclic nature of cell division characterised by periods of DNA synthesis (S-phase) and segregation of newly synthesized chromosomes (M-phase) interspersed by seeming inactivity, the gap phases, G1 and G2. We now know that G1 and G2 play critical roles in regulating the cell cycle, including monitoring of favourable environmental conditions to facilitate cell division, and ensuring genomic integrity prior to DNA replication and nuclear division. M-phase is usually followed by the physical separation of nascent daughters, termed cytokinesis. These phases where G1 leads to S phase, followed by G2 prior to M phase and the subsequent cytokinesis to produce two daughters, both identical in genomic composition and cellular morphology are what might be termed an archetypal cell division. Studies of development of many different organs in different species have demonstrated that this stereotypical cell cycle is often subverted to produce specific developmental outcomes, and examples from over 100 years of analysis of the development of Drosophila melanogaster have uncovered many different modes of cell division within this one species.
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Affiliation(s)
- Qiaolin Yang
- Department of Anatomy and Physiology, University of Melbourne, Melbourne, VIC 3010, Australia
| | - Fernando Wijaya
- Department of Anatomy and Physiology, University of Melbourne, Melbourne, VIC 3010, Australia
| | - Ridam Kapoor
- Department of Anatomy and Physiology, University of Melbourne, Melbourne, VIC 3010, Australia
| | - Harshaa Chandrasekaran
- Department of Anatomy and Physiology, University of Melbourne, Melbourne, VIC 3010, Australia
| | - Siddhant Jagtiani
- Department of Anatomy and Physiology, University of Melbourne, Melbourne, VIC 3010, Australia
| | - Izaac Moran
- Department of Anatomy and Physiology, University of Melbourne, Melbourne, VIC 3010, Australia
| | - Gary R. Hime
- Department of Anatomy and Physiology, University of Melbourne, Melbourne, VIC 3010, Australia
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6
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Coticchio G, Lagalla C, Taggi M, Cimadomo D, Rienzi L. Embryo multinucleation: detection, possible origins, and implications for treatment. Hum Reprod 2024; 39:2392-2399. [PMID: 39173609 DOI: 10.1093/humrep/deae186] [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: 05/02/2024] [Revised: 07/15/2024] [Indexed: 08/24/2024] Open
Abstract
Cell cycle regulation is crucial to assure expansion of a cell population, while preserving genome integrity. This notion is especially relevant to fertilization and early embryo development, a time when the cell cycle transforms from meiotic into mitotic cycles. Zygote-to-embryo transition is acutely error-prone, causing major developmental perturbations, including cleavage delays, tri- and multi-chotomous cleavages, and cell fragmentation. Another such alteration is bi- and multinucleation, consisting of the simultaneous formation of two or more nuclei at interphase. Indeed, multinucleation affects a large proportion of early human embryos, typically at the two-cell stage. Mechanistically, several factors, including spindle dysfunction, failed cleavage, and cell fusion, may generate this cell anomaly. In assisted reproduction treatment, multinucleation is associated with reduced developmental rates and lower implantation rates in Days 2-3 embryo transfers. However, many multinucleated embryos can develop to the blastocyst stage. In blastocyst transfers, the current evidence does not suggest a major impact of a previous history of multinucleation on the odds of euploidy or successful treatment outcomes. Human embryo multinucleation remains a not-fully-understood but developmentally relevant and intriguing phenomenon which requires further research of its generative mechanisms and clinical implications.
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Affiliation(s)
| | | | - Marilena Taggi
- IVIRMA Global Research Alliance, Genera, Clinica Valle Giulia, Rome, Italy
| | - Danilo Cimadomo
- IVIRMA Global Research Alliance, Genera, Clinica Valle Giulia, Rome, Italy
| | - Laura Rienzi
- IVIRMA Global Research Alliance, Genera, Clinica Valle Giulia, Rome, Italy
- Department of Biomolecular Sciences, University of Urbino "Carlo Bo", Urbino, Italy
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7
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Farrell KC, Wang JT, Stearns T. Spindle assembly checkpoint-dependent mitotic delay is required for cell division in absence of centrosomes. eLife 2024; 12:RP84875. [PMID: 39092485 PMCID: PMC11296703 DOI: 10.7554/elife.84875] [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] [Indexed: 08/04/2024] Open
Abstract
The spindle assembly checkpoint (SAC) temporally regulates mitosis by preventing progression from metaphase to anaphase until all chromosomes are correctly attached to the mitotic spindle. Centrosomes refine the spatial organization of the mitotic spindle at the spindle poles. However, centrosome loss leads to elongated mitosis, suggesting that centrosomes also inform the temporal organization of mitosis in mammalian cells. Here, we find that the mitotic delay in acentrosomal cells is enforced by the SAC in a MPS1-dependent manner, and that a SAC-dependent mitotic delay is required for bipolar cell division to occur in acentrosomal cells. Although acentrosomal cells become polyploid, polyploidy is not sufficient to cause dependency on a SAC-mediated delay to complete cell division. Rather, the division failure in absence of MPS1 activity results from mitotic exit occurring before acentrosomal spindles can become bipolar. Furthermore, prevention of centrosome separation suffices to make cell division reliant on a SAC-dependent mitotic delay. Thus, centrosomes and their definition of two spindle poles early in mitosis provide a 'timely two-ness' that allows cell division to occur in absence of a SAC-dependent mitotic delay.
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Affiliation(s)
- KC Farrell
- Department of Biology, Stanford UniversityStanfordUnited States
| | - Jennifer T Wang
- Department of Biology, Stanford UniversityStanfordUnited States
| | - Tim Stearns
- Department of Biology, Stanford UniversityStanfordUnited States
- Department of Genetics, Stanford University School of MedicineStanfordUnited States
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8
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Porokh V, Kyjovská D, Martonová M, Klenková T, Otevřel P, Kloudová S, Holubcová Z. Zygotic spindle orientation defines cleavage pattern and nuclear status of human embryos. Nat Commun 2024; 15:6369. [PMID: 39075061 PMCID: PMC11286845 DOI: 10.1038/s41467-024-50732-z] [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: 07/31/2023] [Accepted: 07/19/2024] [Indexed: 07/31/2024] Open
Abstract
The first embryonic division represents a starting point for the development of a new individual. In many species, tight control over the first embryonic division ensures its accuracy. However, the first division in humans is often erroneous and can impair embryo development. To delineate the spatiotemporal organization of the first mitotic division typical for normal human embryo development, we systematically analyzed a unique timelapse dataset of 300 IVF embryos that developed into healthy newborns. The zygotic division pattern of these best-quality embryos was compared to their siblings that failed to implant or arrested during cleavage stage. We show that division at the right angle to the juxtaposed pronuclei is preferential and supports faithful zygotic division. Alternative configurations of the first mitosis are associated with reduced clustering of nucleoli and multinucleation at the 2-cell stage, which are more common in women of advanced age. Collectively, these data imply that orientation of the first division predisposes human embryos to genetic (in)stability and may contribute to aneuploidy and age-related infertility.
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Affiliation(s)
- Volodymyr Porokh
- Department of Histology and Embryology, Faculty of Medicine, Masaryk University, Brno, Czech Republic
| | - Drahomíra Kyjovská
- Reprofit International, Clinic of Reproductive Medicine, Brno, Czech Republic
| | - Martina Martonová
- Reprofit International, Clinic of Reproductive Medicine, Brno, Czech Republic
| | - Tereza Klenková
- Reprofit International, Clinic of Reproductive Medicine, Brno, Czech Republic
| | - Pavel Otevřel
- Reprofit International, Clinic of Reproductive Medicine, Brno, Czech Republic
| | - Soňa Kloudová
- Department of Histology and Embryology, Faculty of Medicine, Masaryk University, Brno, Czech Republic
- Reprofit International, Clinic of Reproductive Medicine, Brno, Czech Republic
| | - Zuzana Holubcová
- Department of Histology and Embryology, Faculty of Medicine, Masaryk University, Brno, Czech Republic.
- Reprofit International, Clinic of Reproductive Medicine, Brno, Czech Republic.
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9
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Rémillard-Labrosse G, Cohen S, Boucher É, Gagnon K, Vasilev F, Mihajlović AI, FitzHarris G. Oocyte and embryo culture under oil profoundly alters effective concentrations of small molecule inhibitors. Front Cell Dev Biol 2024; 12:1337937. [PMID: 38544820 PMCID: PMC10966923 DOI: 10.3389/fcell.2024.1337937] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Accepted: 02/19/2024] [Indexed: 11/11/2024] Open
Abstract
Culture of oocytes and embryos in media under oil is a cornerstone of fertility treatment, and extensively employed in experimental investigation of early mammalian development. It has been noted anecdotally by some that certain small molecule inhibitors might lose activity in oil-covered culture systems, presumably by drug partitioning into the oil. Here we took a pseudo-pharmacological approach to appraise this formally using mouse oocytes and embryos. Using different culture dish designs with defined media:oil volume ratios, we show that the EC50 of the widely employed microtubule poison nocodazole shifts as a function of the media:oil ratio, such that nocodazole concentrations that prevent cell division in oil-free culture fail to in oil-covered media drops. Relatively subtle changes in culture dish design lead to measurable changes in EC50. This effect is not specific to one type of culture oil, and can be readily observed both in oocyte and embryo culture experiments. We subsequently applied a similar approach to a small panel of widely employed cell cycle-related inhibitors, finding that most lose activity in standard oil-covered oocyte/embryo culture systems. Our data suggest that loss of small molecule activity in oil-covered oocyte and embryo culture is a widespread phenomenon with potentially far-reaching implications for data reproducibility, and we recommend avoiding oil-covered culture for experiments employing inhibitors/drugs wherever possible.
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Affiliation(s)
| | - Sydney Cohen
- Centre de Recherche du Centre Hospitalier de I’Université de Montréal (CRCHUM), Montréal, QC, Canada
| | - Éliane Boucher
- Centre de Recherche du Centre Hospitalier de I’Université de Montréal (CRCHUM), Montréal, QC, Canada
| | - Kéryanne Gagnon
- Centre de Recherche du Centre Hospitalier de I’Université de Montréal (CRCHUM), Montréal, QC, Canada
| | - Filip Vasilev
- Centre de Recherche du Centre Hospitalier de I’Université de Montréal (CRCHUM), Montréal, QC, Canada
| | - Aleksandar I. Mihajlović
- Centre de Recherche du Centre Hospitalier de I’Université de Montréal (CRCHUM), Montréal, QC, Canada
| | - Greg FitzHarris
- Centre de Recherche du Centre Hospitalier de I’Université de Montréal (CRCHUM), Montréal, QC, Canada
- Department of Obstetrics and Gynaecology, Université de Montréal, Montréal, QC, Canada
- Department of Pathology and Cell Biology, Université de Montréal, Montréal, QC, Canada
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10
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Zhou Y, Xu MF, Chen J, Zhang JL, Wang XY, Huang MH, Wei YL, She ZY. Loss-of-function of kinesin-5 KIF11 causes microcephaly, chorioretinopathy, and developmental disorders through chromosome instability and cell cycle arrest. Exp Cell Res 2024; 436:113975. [PMID: 38367657 DOI: 10.1016/j.yexcr.2024.113975] [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: 12/13/2023] [Revised: 02/02/2024] [Accepted: 02/12/2024] [Indexed: 02/19/2024]
Abstract
Kinesin motors play a fundamental role in development by controlling intracellular transport, spindle assembly, and microtubule organization. In humans, patients carrying mutations in KIF11 suffer from an autosomal dominant inheritable disease called microcephaly with or without chorioretinopathy, lymphoedema, or mental retardation (MCLMR). While mitotic functions of KIF11 proteins have been well documented in centrosome separation and spindle assembly, cellular mechanisms underlying KIF11 dysfunction and MCLMR remain unclear. In this study, we generate KIF11-inhibition chick and zebrafish models and find that KIF11 inhibition results in microcephaly, chorioretinopathy, and severe developmental defects in vivo. Notably, loss-of-function of KIF11 causes the formation of monopolar spindle and chromosome misalignment, which finally contribute to cell cycle arrest, chromosome instability, and cell death. Our results demonstrate that KIF11 is crucial for spindle assembly, chromosome alignment, and cell cycle progression of progenitor stem cells, indicating a potential link between polyploidy and MCLMR. Our data have revealed that KIF11 inhibition cause microcephaly, chorioretinopathy, and development disorders through the formation of monopolar spindle, polyploid, and cell cycle arrest.
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Affiliation(s)
- Yi Zhou
- Department of Cell Biology and Genetics, The School of Basic Medical Sciences, Fujian Medical University, Fuzhou, Fujian, 350122, China; Key Laboratory of Stem Cell Engineering and Regenerative Medicine, Fujian Province University, Fuzhou, Fujian, 350122, China
| | - Meng-Fei Xu
- Department of Cell Biology and Genetics, The School of Basic Medical Sciences, Fujian Medical University, Fuzhou, Fujian, 350122, China; Key Laboratory of Stem Cell Engineering and Regenerative Medicine, Fujian Province University, Fuzhou, Fujian, 350122, China
| | - Jie Chen
- Department of Cell Biology and Genetics, The School of Basic Medical Sciences, Fujian Medical University, Fuzhou, Fujian, 350122, China; Key Laboratory of Stem Cell Engineering and Regenerative Medicine, Fujian Province University, Fuzhou, Fujian, 350122, China
| | - Jing-Lian Zhang
- Department of Cell Biology and Genetics, The School of Basic Medical Sciences, Fujian Medical University, Fuzhou, Fujian, 350122, China; Key Laboratory of Stem Cell Engineering and Regenerative Medicine, Fujian Province University, Fuzhou, Fujian, 350122, China
| | - Xin-Yao Wang
- Department of Cell Biology and Genetics, The School of Basic Medical Sciences, Fujian Medical University, Fuzhou, Fujian, 350122, China; Key Laboratory of Stem Cell Engineering and Regenerative Medicine, Fujian Province University, Fuzhou, Fujian, 350122, China
| | - Min-Hui Huang
- Department of Cell Biology and Genetics, The School of Basic Medical Sciences, Fujian Medical University, Fuzhou, Fujian, 350122, China; Key Laboratory of Stem Cell Engineering and Regenerative Medicine, Fujian Province University, Fuzhou, Fujian, 350122, China
| | - Ya-Lan Wei
- Medical Research Center, Fujian Maternity and Child Health Hospital, Fuzhou, Fujian, 350001, China; College of Clinical Medicine for Obstetrics & Gynecology and Pediatrics, Fujian Medical University, Fuzhou, Fujian, 350122, China
| | - Zhen-Yu She
- Department of Cell Biology and Genetics, The School of Basic Medical Sciences, Fujian Medical University, Fuzhou, Fujian, 350122, China; Key Laboratory of Stem Cell Engineering and Regenerative Medicine, Fujian Province University, Fuzhou, Fujian, 350122, China.
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11
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Yin L, Wang W, Pang W, Yang G, Gao L, Chu G. Insulin regulates gap junction intercellular communication in porcine granulosa cells through modulation of connexin43 protein expression. Theriogenology 2023; 212:172-180. [PMID: 37738821 DOI: 10.1016/j.theriogenology.2023.09.008] [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: 05/13/2023] [Revised: 09/11/2023] [Accepted: 09/13/2023] [Indexed: 09/24/2023]
Abstract
Gap junction intercellular communication (GJIC) among granulosa cells plays an important role in folliculogenesis, and it is temporal-spatially regulated during follicular development. Connexin (Cx) proteins predominantly form the basal structure of gap junctions in granulosa cells. In our study, immunohistochemical analysis revealed that Cx43 is the most widely expressed connexin in porcine follicles, especially among the large antral follicles. With application of insulin on porcine granulosa cells, we found that insulin significantly facilitated the protein level of Cx43, not mRNA level. This process is dependent on the phosphorylated activities of AKT and Erk since selective AKT and Erk inhibitors, LY294002 and U0126, respectively, hampered the potential of insulin to up-regulate Cx43 protein expression. As a consequence, the insulin-enhanced Cx43-couple GJIC activity in porcine granulosa cells was corresponding attenuated by the administration of LY294002 and U0126. Our findings provide a new insight into the molecular mechanisms by which insulin mediates cell-cell communication in porcine granulosa cells and sheds light on nutrition-reproduction interactions.
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Affiliation(s)
- Lin Yin
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, 712100, PR China
| | - Wusu Wang
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, 712100, PR China
| | - Weijun Pang
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, 712100, PR China
| | - Gongshe Yang
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, 712100, PR China
| | - Lei Gao
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, 712100, PR China.
| | - Guiyan Chu
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, 712100, PR China.
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12
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Bloomfield M, Cimini D. The fate of extra centrosomes in newly formed tetraploid cells: should I stay, or should I go? Front Cell Dev Biol 2023; 11:1210983. [PMID: 37576603 PMCID: PMC10413984 DOI: 10.3389/fcell.2023.1210983] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2023] [Accepted: 07/17/2023] [Indexed: 08/15/2023] Open
Abstract
An increase in centrosome number is commonly observed in cancer cells, but the role centrosome amplification plays along with how and when it occurs during cancer development is unclear. One mechanism for generating cancer cells with extra centrosomes is whole genome doubling (WGD), an event that occurs in over 30% of human cancers and is associated with poor survival. Newly formed tetraploid cells can acquire extra centrosomes during WGD, and a generally accepted model proposes that centrosome amplification in tetraploid cells promotes cancer progression by generating aneuploidy and chromosomal instability. Recent findings, however, indicate that newly formed tetraploid cells in vitro lose their extra centrosomes to prevent multipolar cell divisions. Rather than persistent centrosome amplification, this evidence raises the possibility that it may be advantageous for tetraploid cells to initially restore centrosome number homeostasis and for a fraction of the population to reacquire additional centrosomes in the later stages of cancer evolution. In this review, we explore the different evolutionary paths available to newly formed tetraploid cells, their effects on centrosome and chromosome number distribution in daughter cells, and their probabilities of long-term survival. We then discuss the mechanisms that may alter centrosome and chromosome numbers in tetraploid cells and their relevance to cancer progression following WGD.
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Affiliation(s)
- Mathew Bloomfield
- Department of Biological Sciences and Fralin Life Sciences Institute, Virginia Tech, Blacksburg, VA, United States
| | - Daniela Cimini
- Department of Biological Sciences and Fralin Life Sciences Institute, Virginia Tech, Blacksburg, VA, United States
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13
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Lee C, Leem J, Oh JS. Selective utilization of non-homologous end-joining and homologous recombination for DNA repair during meiotic maturation in mouse oocytes. Cell Prolif 2022; 56:e13384. [PMID: 36564861 PMCID: PMC10068936 DOI: 10.1111/cpr.13384] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2022] [Revised: 11/29/2022] [Accepted: 12/08/2022] [Indexed: 12/25/2022] Open
Abstract
DNA double-strand breaks (DSBs) are highly toxic lesions that can cause genomic instability and can be repaired by non-homologous end-joining (NHEJ) and homologous recombination (HR) pathways. Despite extensive studies about DSB repair pathways, the roles of each pathway during meiotic maturation in oocytes are not well understood. Here we show that oocytes selectively utilize NHEJ and HR to repair DSBs during meiotic maturation. Inhibition of NHEJ impaired the meiotic maturation of oocytes with DNA damage by activating the spindle assembly checkpoint (SAC) with a concomitant increase in metaphase I (MI) arrest and DNA damage levels. In contrast, oocytes with DNA damage bypassed SAC-mediated MI arrest despite the presence of fragmented DNA when HR was inhibited. Notably, this bypass of SAC arrest by HR inhibition was associated with a loss of centromere integrity and subsequent impairment of chromosome architecture. Our results demonstrate that, while NHEJ is critical for the meiotic maturation of oocytes with DNA damage, HR is essential to maintain centromere integrity against DNA damage during meiotic maturation, revealing distinct roles of NHEJ and HR during meiotic maturation in mouse oocytes.
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Affiliation(s)
- Crystal Lee
- Department of Integrative Biotechnology, Sungkyunkwan University, Suwon, South Korea
| | - Jiyeon Leem
- Department of Integrative Biotechnology, Sungkyunkwan University, Suwon, South Korea
| | - Jeong Su Oh
- Department of Integrative Biotechnology, Sungkyunkwan University, Suwon, South Korea.,Biomedical Institute for Convergence at SKKU (BICS), Sungkyunkwan University, Suwon, South Korea
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14
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Ye Y, Homer HA. Two-step nuclear centring by competing microtubule- and actin-based mechanisms in 2-cell mouse embryos. EMBO Rep 2022; 23:e55251. [PMID: 36214648 PMCID: PMC9638869 DOI: 10.15252/embr.202255251] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Revised: 09/01/2022] [Accepted: 09/12/2022] [Indexed: 11/23/2024] Open
Abstract
Microtubules typically promote nuclear centring during early embryonic divisions in centrosome-containing vertebrates. In acentrosomal mouse zygotes, microtubules also centre male and female pronuclei prior to the first mitosis, this time in concert with actin. How nuclear centring is brought about in subsequent acentrosomal embryonic divisions has not been studied. Here, using time-lapse imaging in mouse embryos, we find that although nuclei are delivered to the cell centre upon completion of the first mitotic anaphase, the majority do not remain stationary and instead travel all the way to the cortex in a microtubule-dependent manner. High cytoplasmic viscosity in 2-cell embryos is associated with non-diffusive mechanisms involving actin for subsequent nuclear centring when microtubules again exert a negative influence. Thus, following the first mitotic division, pro-centring actin-dependent mechanisms work against microtubule-dependent de-centring forces. Disrupting the equilibrium of this tug-of-war compromises nuclear centring and symmetry of the subsequent division potentially risking embryonic development. This circuitous centring process exposes an embryonic vulnerability imposed by microtubule-dependent de-centring forces.
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Affiliation(s)
- Yunan Ye
- The Christopher Chen Oocyte Biology Research Laboratory, Centre for Clinical ResearchThe University of QueenslandHerstonQLDAustralia
| | - Hayden A Homer
- The Christopher Chen Oocyte Biology Research Laboratory, Centre for Clinical ResearchThe University of QueenslandHerstonQLDAustralia
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15
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Allais A, FitzHarris G. Absence of a robust mitotic timer mechanism in early preimplantation mouse embryos leads to chromosome instability. Development 2022; 149:275859. [DOI: 10.1242/dev.200391] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Accepted: 05/12/2022] [Indexed: 01/07/2023]
Abstract
ABSTRACT
Preimplantation embryos often consist of a combination of euploid and aneuploid cells, suggesting that safeguards preventing the generation and propagation of aneuploid cells in somatic cells might be deficient in embryos. In somatic cells, a mitotic timer mechanism has been described, in which even a small increase in the duration of M phase can cause a cell cycle arrest in the subsequent interphase, preventing further propagation of cells that have undergone a potentially hazardously long M phase. Here, we report that cell divisions in the mouse embryo and embryonic development continue even after a mitotic prolongation of several hours. However, similar M-phase extensions caused cohesion fatigue, resulting in prematurely separated sister chromatids and the production of micronuclei. Only extreme prolongation of M phase caused a subsequent interphase arrest, through a mechanism involving DNA damage. Our data suggest that the simultaneous absence of a robust mitotic timer and susceptibility of the embryo to cohesion fatigue could contribute to chromosome instability in mammalian embryos.
This article has an associated ‘The people behind the papers’ interview.
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Affiliation(s)
- Adélaïde Allais
- Centre de recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM) 1 , H2X 0A9 Montréal, Québec , Canada
| | - Greg FitzHarris
- Centre de recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM) 1 , H2X 0A9 Montréal, Québec , Canada
- Université de Montréal 2 Department of OBGYN, and Department of Pathology and Cell Biology , , H3T 1C5 Montréal, Québec , Canada
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16
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Calder MD, Chen R, MacDonald A, MacNeily Z, Leung ZCL, Adus S, Cui S, Betts DH, Rafea BA, Watson AJ. Effects of palmitic acid on localization of embryo cell fate and blastocyst formation gene products. Reproduction 2022; 163:133-143. [PMID: 35038315 PMCID: PMC8859922 DOI: 10.1530/rep-21-0354] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Accepted: 01/13/2022] [Indexed: 12/04/2022]
Abstract
As obese and overweight patients commonly display hyperlipidemia and are increasingly accessing fertility clinics for their conception needs, our studies are directed at understanding the effects of hyperlipidemia on early pregnancy. We have focused on investigating palmitic acid (PA) and oleic acid (OA) treatment alone and in combination from the mouse two-cell stage embryos as a model for understanding their effects on the mammalian preimplantation embryo. We recently reported that PA exerts a negative effect on mouse two-cell progression to the blastocyst stage, whereas OA co-treatment reverses that negative effect. In the present study, we hypothesized that PA treatment of mouse embryos would disrupt proper localization of cell fate determining and blastocyst formation gene products and that co-treatment with OA would reverse these effects. Our results demonstrate that PA treatment significantly (P < 0.05) reduces blastocyst development and cell number but did not prevent nuclear localization of YAP in outer cells. PA treatment significantly reduced the number of OCT4+ and CDX2+ nuclei. PA-treated embryos had lower expression of blastocyst formation proteins (E-cadherin, ZO-1 and Na/K-ATPase alpha1 subunit). Importantly, co-treatment of embryos with OA reversed PA-induced effects on blastocyst development and increased inner cell mass (ICM) and trophectoderm (TE) cell numbers and expression of blastocyst formation proteins. Our findings demonstrate that PA treatment does not impede cell fate gene localization but does disrupt proper blastocyst formation gene localization during mouse preimplantation development. OA treatment is protective and reverses PA's detrimental effects. The results advance our understanding of the impact of FFA exposure on mammalian preimplantation development.
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Affiliation(s)
- Michele D Calder
- Department of Obstetrics and Gynaecology, The University of Western Ontario, London, Ontario, Canada
- Department of Physiology and Pharmacology, The University of Western Ontario, London, Ontario, Canada
- The Children’s Health Research Institute – Lawson Health Research Institute, London, Ontario, Canada
| | - Robert Chen
- Department of Physiology and Pharmacology, The University of Western Ontario, London, Ontario, Canada
- The Children’s Health Research Institute – Lawson Health Research Institute, London, Ontario, Canada
| | - Anastasia MacDonald
- Department of Physiology and Pharmacology, The University of Western Ontario, London, Ontario, Canada
- The Children’s Health Research Institute – Lawson Health Research Institute, London, Ontario, Canada
| | - Zoe MacNeily
- Department of Physiology and Pharmacology, The University of Western Ontario, London, Ontario, Canada
- The Children’s Health Research Institute – Lawson Health Research Institute, London, Ontario, Canada
| | - Zuleika Chin Lai Leung
- Department of Obstetrics and Gynaecology, The University of Western Ontario, London, Ontario, Canada
- Department of Physiology and Pharmacology, The University of Western Ontario, London, Ontario, Canada
- The Children’s Health Research Institute – Lawson Health Research Institute, London, Ontario, Canada
| | - Samira Adus
- Department of Physiology and Pharmacology, The University of Western Ontario, London, Ontario, Canada
- The Children’s Health Research Institute – Lawson Health Research Institute, London, Ontario, Canada
| | - Shiyu Cui
- Department of Physiology and Pharmacology, The University of Western Ontario, London, Ontario, Canada
- The Children’s Health Research Institute – Lawson Health Research Institute, London, Ontario, Canada
| | - Dean H Betts
- Department of Obstetrics and Gynaecology, The University of Western Ontario, London, Ontario, Canada
- Department of Physiology and Pharmacology, The University of Western Ontario, London, Ontario, Canada
- The Children’s Health Research Institute – Lawson Health Research Institute, London, Ontario, Canada
| | - Basim Abu Rafea
- Department of Obstetrics and Gynaecology, The University of Western Ontario, London, Ontario, Canada
- The Children’s Health Research Institute – Lawson Health Research Institute, London, Ontario, Canada
| | - Andrew J Watson
- Department of Obstetrics and Gynaecology, The University of Western Ontario, London, Ontario, Canada
- Department of Physiology and Pharmacology, The University of Western Ontario, London, Ontario, Canada
- The Children’s Health Research Institute – Lawson Health Research Institute, London, Ontario, Canada
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17
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Somatic Hypomethylation of Pericentromeric SST1 Repeats and Tetraploidization in Human Colorectal Cancer Cells. Cancers (Basel) 2021; 13:cancers13215353. [PMID: 34771515 PMCID: PMC8582499 DOI: 10.3390/cancers13215353] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Revised: 10/06/2021] [Accepted: 10/21/2021] [Indexed: 01/08/2023] Open
Abstract
Somatic DNA hypomethylation and aneuploidy are hallmarks of cancer, and there is evidence for a causal relationship between them in knockout mice but not in human cancer. The non-mobile pericentromeric repetitive elements SST1 are hypomethylated in about 17% of human colorectal cancers (CRC) with some 5-7% exhibiting strong age-independent demethylation. We studied the frequency of genome doubling, a common event in solid tumors linked to aneuploidy, in randomly selected single cell clones of near-diploid LS174T human CRC cells differing in their level of SST1 demethylation. Near-diploid LS174T cells underwent frequent genome-doubling events generating near-tetraploid clones with lower levels of SST1 methylation. In primary CRC, strong SST1 hypomethylation was significantly associated with global genomic hypomethylation and mutations in TP53. This work uncovers the association of the naturally occurring demethylation of the SST1 pericentromeric repeat with the onset of spontaneous tetraploidization in human CRC cells in culture and with TP53 mutations in primary CRCs. Altogether, our findings provide further support for an oncogenic pathway linking somatic hypomethylation and genetic copy number alterations in a subset of human CRC.
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18
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Winiarczyk D, Piliszek A, Sampino S, Lukaszewicz M, Modli Ski JA. Embryo structure reorganisation reduces the probability of apoptosis in preimplantation mouse embryos. Reprod Fertil Dev 2021; 33:725-735. [PMID: 34488937 DOI: 10.1071/rd21074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Accepted: 07/29/2021] [Indexed: 11/23/2022] Open
Abstract
Programmed cell death plays a key role in mammalian development because the morphological events of an organism's formation are dependent on apoptosis. In the mouse development, the first apoptotic waves occur physiologically at the blastocyst stage. Cell number and the mean nucleus to cytoplasm (N/C) ratio increase exponentially throughout subsequent embryo cleavages, while cell volume concurrently decreases from the zygote to blastocyst stage. In this study we tested the hypothesis that reorganisation of the embryo structure by manipulating cell number, the N/C ratio and the cell volume of 2-cell embryos may result in the earlier and more frequent occurrence of apoptosis. The results indicate that doubling ('Aggregates' group) or halving ('Embryos 1/2' group) the initial cell number and modifying embryo volume, ploidy ('Embryos 4n' group) and the N/C ratio ('Embryos 2/1' group) reduce the probability of apoptosis in the resulting embryos. There was a higher probability of apoptosis in the inner cell mass of the blastocyst, but apoptotic cells were never observed at the morula stage in any of the experimental groups. Thus, manipulation of cell number, embryo volume, the N/C ratio and ploidy cause subtle changes in the occurrence of apoptosis, although these are mostly dependent on embryo stage and cell lineage (trophectoderm or inner cell mass), which have the greatest effect on the probability of apoptosis.
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Affiliation(s)
- Dawid Winiarczyk
- Department of Experimental Embryology, Institute of Genetics and Animal Biotechnology of the Polish Academy of Sciences, Jastrzebiec, Poland; and Corresponding authors. ;
| | - Anna Piliszek
- Department of Experimental Embryology, Institute of Genetics and Animal Biotechnology of the Polish Academy of Sciences, Jastrzebiec, Poland
| | - Silvestre Sampino
- Department of Experimental Embryology, Institute of Genetics and Animal Biotechnology of the Polish Academy of Sciences, Jastrzebiec, Poland
| | - Marek Lukaszewicz
- Department of Animal Improvement and Nutrigenomics, Institute of Genetics and Animal Biotechnology of the Polish Academy of Sciences, Jastrzebiec, Poland
| | - Jacek Andrzej Modli Ski
- Department of Experimental Embryology, Institute of Genetics and Animal Biotechnology of the Polish Academy of Sciences, Jastrzebiec, Poland; and Corresponding authors. ;
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19
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Distinct classes of lagging chromosome underpin age-related oocyte aneuploidy in mouse. Dev Cell 2021; 56:2273-2283.e3. [PMID: 34428397 DOI: 10.1016/j.devcel.2021.07.022] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Revised: 06/07/2021] [Accepted: 07/29/2021] [Indexed: 12/18/2022]
Abstract
Chromosome segregation errors that cause oocyte aneuploidy increase in frequency with maternal age and are considered a major contributing factor of age-related fertility decline in females. Lagging anaphase chromosomes are a common age-associated phenomenon in oocytes, but whether anaphase laggards actually missegregate and cause aneuploidy is unclear. Here, we show that lagging chromosomes in mouse oocytes comprise two mechanistically distinct classes of chromosome motion that we refer to as "class-I" and "class-II" laggards. We use imaging approaches and mechanistic interventions to dissociate the two classes and find that whereas class-II laggards are largely benign, class-I laggards frequently directly lead to aneuploidy. Most notably, a controlled prolongation of meiosis I specifically lessens class-I lagging to prevent aneuploidy. Our data thus reveal lagging chromosomes to be a cause of age-related aneuploidy in mouse oocytes and suggest that manipulating the cell cycle could increase the yield of useful oocytes in some contexts.
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20
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Nagai H, Okada M, Nagai Y, Sakuraba Y, Okae H, Suzuki R, Sugimura S. Abnormal cleavage is involved in the self-correction of bovine preimplantation embryos. Biochem Biophys Res Commun 2021; 562:76-82. [PMID: 34044324 DOI: 10.1016/j.bbrc.2021.05.028] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2021] [Accepted: 05/09/2021] [Indexed: 10/21/2022]
Abstract
Chromosome instability leading to aneuploidy during early cleavage is well known in humans and cattle. Partial compaction (PC), which occurs only in some blastomeres, is suggested as a self-correction mechanism through which human embryos avoid aneuploid mosaicism. Partially compacted embryos show abnormal cleavages more frequently during early development; however, the mechanism by which blastomeres are excluded has not been elucidated. Here, we confirmed PC in approximately half of the tested bovine embryos, similar to that in human embryos. DNA sequencing of single-cell and intact embryos revealed that the morulae that excluded some blastomeres had euploidy, but many of the excluded blastomeres had aneuploidy. Time-lapse imaging of zygotes without the zona pellucida revealed that the excluded blastomeres underwent reverse and direct cleavages, which are abnormal cleavages, more frequently than the blastomeres involved in compaction. These results suggest the potential role of abnormal cleavage in the self-correction mechanism during the development of mammalian preimplantation embryos.
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Affiliation(s)
- Hiroki Nagai
- Department of Biological Production, Tokyo University of Agriculture and Technology, Tokyo, 183-8509, Japan
| | - Mai Okada
- Department of Biological Production, Tokyo University of Agriculture and Technology, Tokyo, 183-8509, Japan
| | | | | | - Hiroaki Okae
- Department of Informative Genetics, Environment and Genome Research Center, Graduate School of Medicine, Tohoku University, Miyagi 980-8575, Japan
| | - Ryosuke Suzuki
- Department of Biological Production, Tokyo University of Agriculture and Technology, Tokyo, 183-8509, Japan; Kanagawa Ladies Clinic, Kanagawa, 221-0822, Japan
| | - Satoshi Sugimura
- Department of Biological Production, Tokyo University of Agriculture and Technology, Tokyo, 183-8509, Japan.
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21
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Storchova Z. Consequences of mitotic failure - The penalties and the rewards. Semin Cell Dev Biol 2021; 117:149-158. [PMID: 33820699 DOI: 10.1016/j.semcdb.2021.03.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 03/12/2021] [Accepted: 03/13/2021] [Indexed: 12/14/2022]
Abstract
Eukaryotic cells are usually diploid, meaning they contain two copies of each chromosome. However, aberrant chromosome numbers due to both, chromosome gains and losses, are often observed in nature. They can occur as a planned developmental step, but are more often an uninvited result of mitotic failure. Recent discoveries have improved our understanding of the cellular effects of aneuploidy - uneven chromosome numbers, and polyploidy - multiplication of entire sets of chromosomes - in eukaryotic cells. The results show that mitotic errors lead to rapid and extensive modifications of many cellular processes and affect proliferation, proteome balance, genome stability and more. The findings picture the cellular response to aneuploidy and polyploidy as a complex, tissue and context dependent network of events. Here I review the latest discoveries, with an emphasis on pathological aspects of aneuploidy and polyploidy in human cells.
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Affiliation(s)
- Zuzana Storchova
- Department of Molecular Genetics, TU Kaiserslautern, Paul Ehrlich Str. 24, 67663 Kaiserslautern, Germany.
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22
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Levy B, Hoffmann ER, McCoy RC, Grati FR. Chromosomal mosaicism: Origins and clinical implications in preimplantation and prenatal diagnosis. Prenat Diagn 2021; 41:631-641. [PMID: 33720449 DOI: 10.1002/pd.5931] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Revised: 03/03/2021] [Accepted: 03/06/2021] [Indexed: 12/18/2022]
Abstract
The diagnosis of chromosomal mosaicism in the preimplantation and prenatal stage is fraught with uncertainty and multiple factors need to be considered in order to gauge the likely impact. The clinical effects of chromosomal mosaicism are directly linked to the type of the imbalance (size, gene content, and copy number), the timing of the initial event leading to mosaicism during embryogenesis/fetal development, the distribution of the abnormal cells throughout the various tissues within the body as well as the ratio of normal/abnormal cells within each of those tissues. Additional factors such as assay noise and culture artifacts also have an impact on the significance and management of mosaic cases. Genetic counseling is an important part of educating patients about the likelihood of having a liveborn with a chromosome abnormality and these risks differ according to the time of ascertainment and the tissue where the mosaic cells were initially discovered. Each situation needs to be assessed on a case-by-case basis and counseled accordingly. This review will discuss the clinical impact of finding mosaicism through: embryo biopsy, chorionic villus sampling, amniocentesis, and noninvasive prenatal testing using cell-free DNA.
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Affiliation(s)
- Brynn Levy
- Department of Pathology and Cell Biology, Columbia University Irving Medical Center, New York, New York, USA
| | - Eva R Hoffmann
- Department of Cellular and Molecular Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Rajiv C McCoy
- Department of Biology, Johns Hopkins University, Baltimore, Maryland, USA
| | - Francesca R Grati
- Research and Development, Cytogenetics and Medical Genetics Unit, TOMA Advanced Biomedical Assays, S.p.A. (Impact Lab), Busto Arsizio, Varese, Italy
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23
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Tyagi IS, Chen S, Khan MA, Xie J, Li PY, Long X, Xue H. Intrinsic and chemically-induced daughter number variations in cancer cell lines. Cell Cycle 2021; 20:537-549. [PMID: 33596747 DOI: 10.1080/15384101.2021.1883363] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
Abstract
Multipolar mitosis was observed in cancer cells under mechanical stress or drug treatment. However, a comprehensive understanding of its basic properties and significance to cancer cell biology is lacking. In the present study, live-cell imaging was employed to investigate the division and nucleation patterns in four different cell lines. Multi-daughter divisions were observed in the three cancer cell lines HepG2, HeLa and A549, but not in the transformed non-cancer cell line RPE1. Multi-daughter mother cells displayed multi-nucleation, enlarged cell area, and prolonged division time. Under acidic pH or treatment with the anti-cancer drug 5-fluorouracil (5-FU) or the phytochemical compound wogonin, multi-daughter mitoses were increased to different extents in all three cancer cell lines, reaching as high as 16% of all mitoses. While less than 0.4% of the bi-daughter mitosis were followed by cell fusion events under the various treatment conditions, 50% or more of the multi-daughter mitoses were followed by fusion events at neutral, acidic or alkaline pH. These findings revealed a "Daughter Number Variation" (DNV) process in the cancer cells, with multi-daughter divisions in Stage 1 and cell fusions leading to the formation of cells containing up to five nuclei in Stage 2. The Stage 2-fusions were inhibited by 5-FU in A549 and HeLa, and by wogonin in A549, HeLa and HepG2. The parallel relationship between DNV frequency and malignancy among the different cell lines suggests that the inclusion of anti-fusion agents exemplified by wogonin and 5-FU could be beneficial in combinatory cancer chemotherapies.
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Affiliation(s)
- Iram Shazia Tyagi
- Division of Life Science and Applied Genomics Center, Hong Kong University of Science and Technology, Hong Kong, People's Republic of China
| | - Si Chen
- Division of Life Science and Applied Genomics Center, Hong Kong University of Science and Technology, Hong Kong, People's Republic of China
| | - Muhammad Ajmal Khan
- Division of Life Science and Applied Genomics Center, Hong Kong University of Science and Technology, Hong Kong, People's Republic of China
| | - Jia Xie
- Division of Life Science and Applied Genomics Center, Hong Kong University of Science and Technology, Hong Kong, People's Republic of China
| | - Ping Yin Li
- Division of Life Science and Applied Genomics Center, Hong Kong University of Science and Technology, Hong Kong, People's Republic of China
| | - Xi Long
- Division of Life Science and Applied Genomics Center, Hong Kong University of Science and Technology, Hong Kong, People's Republic of China
| | - Hong Xue
- Division of Life Science and Applied Genomics Center, Hong Kong University of Science and Technology, Hong Kong, People's Republic of China.,Center for Cancer Genomics, School of Basic Medicine and Clinical Pharmacy, China Pharmaceutical University, Nanjing, People's Republic of China
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Bloomfield M, Chen J, Cimini D. Spindle Architectural Features Must Be Considered Along With Cell Size to Explain the Timing of Mitotic Checkpoint Silencing. Front Physiol 2021; 11:596263. [PMID: 33584330 PMCID: PMC7877541 DOI: 10.3389/fphys.2020.596263] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Accepted: 12/23/2020] [Indexed: 11/25/2022] Open
Abstract
Mitosis proceeds through a defined series of events that is largely conserved, but the amount of time needed for their completion can vary in different cells and organisms. In many systems, mitotic duration depends on the time required to satisfy and silence the spindle assembly checkpoint (SAC), also known as the mitotic checkpoint. Because SAC silencing involves trafficking SAC molecules among kinetochores, spindle, and cytoplasm, the size and geometry of the spindle relative to cell volume are expected to affect mitotic duration by influencing the timing of SAC silencing. However, the relationship between SAC silencing, cell size, and spindle dimensions is unclear. To investigate this issue, we used four DLD-1 tetraploid (4N) clones characterized by small or large nuclear and cell size. We found that the small 4N clones had longer mitotic durations than the parental DLD-1 cells and that this delay was due to differences in their metaphase duration. Leveraging a previous mathematical model for spatiotemporal regulation of SAC silencing, we show that the difference in metaphase duration, i.e., SAC silencing time, can be explained by the distinct spindle microtubule densities and sizes of the cell, spindle, and spindle poles in the 4N clones. Lastly, we demonstrate that manipulating spindle geometry can alter mitotic and metaphase duration, consistent with a model prediction. Our results suggest that spindle size does not always scale with cell size in mammalian cells and cell size is not sufficient to explain the differences in metaphase duration. Only when a number of spindle architectural features are considered along with cell size can the kinetics of SAC silencing, and hence mitotic duration, in the different clones be explained.
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Affiliation(s)
- Mathew Bloomfield
- Department of Biological Sciences and Fralin Life Sciences Institute, Virginia Tech, Blacksburg, VA, United States
| | - Jing Chen
- Department of Biological Sciences and Fralin Life Sciences Institute, Virginia Tech, Blacksburg, VA, United States
| | - Daniela Cimini
- Department of Biological Sciences and Fralin Life Sciences Institute, Virginia Tech, Blacksburg, VA, United States
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Kafer GR, Cesare AJ. A Survey of Essential Genome Stability Genes Reveals That Replication Stress Mitigation Is Critical for Peri-Implantation Embryogenesis. Front Cell Dev Biol 2020; 8:416. [PMID: 32548123 PMCID: PMC7274024 DOI: 10.3389/fcell.2020.00416] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Accepted: 05/05/2020] [Indexed: 12/16/2022] Open
Abstract
Murine development demands that pluripotent epiblast stem cells in the peri-implantation embryo increase from approximately 120 to 14,000 cells between embryonic days (E) 4.5 and E7.5. This is possible because epiblast stem cells can complete cell cycles in under 3 h in vivo. To ensure conceptus fitness, epiblast cells must undertake this proliferative feat while maintaining genome integrity. How epiblast cells maintain genome health under such an immense proliferation demand remains unclear. To illuminate the contribution of genome stability pathways to early mammalian development we systematically reviewed knockout mouse data from 347 DDR and repair associated genes. Cumulatively, the data indicate that while many DNA repair functions are dispensable in embryogenesis, genes encoding replication stress response and homology directed repair factors are essential specifically during the peri-implantation stage of early development. We discuss the significance of these findings in the context of the unique proliferative demands placed on pluripotent epiblast stem cells.
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Affiliation(s)
| | - Anthony J. Cesare
- Genome Integrity Unit, Children’s Medical Research Institute, The University of Sydney, Westmead, NSW, Australia
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Macaulay AD, Allais A, FitzHarris G. Chromosome dynamics and spindle microtubule establishment in mouse embryos. FASEB J 2020; 34:8057-8067. [PMID: 32329130 DOI: 10.1096/fj.201902947r] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2019] [Revised: 03/25/2020] [Accepted: 03/31/2020] [Indexed: 11/11/2022]
Abstract
Chromosome segregation errors in mammalian embryos are common and jeopardize embryo health. Here, we perform for the first time 4-Dimensional imaging and tracking of chromosomes and centromeres through each preimplantation mitotic cell division in mouse embryos to define the normal dynamics of chromosome segregation. We show that a microtubule (MT)-dependent inward movement of chromosomes occurs at the time of nuclear envelope breakdown (NEBD), particularly in the earliest cell divisions, to position chromosomes prior to spindle assembly. Establishment of a rudimentary metaphase plate occurs immediately after NEBD, and is followed by a progressive alignment and biorientation of mitotic chromosomes. Stable end-on kinetochore-MT attachments form rapidly and attachment errors are uncommon. Altogether our data describe a rapid and efficient spindle assembly pathway that apparently minimizes the need for canonical MT attachment error correction in normally dividing embryos.
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Affiliation(s)
- Angus D Macaulay
- Centre de Recherche du Centre Hospitalier de l'Université de Montréal, Montreal, QC, Canada
| | - Adélaïde Allais
- Centre de Recherche du Centre Hospitalier de l'Université de Montréal, Montreal, QC, Canada
| | - Greg FitzHarris
- Centre de Recherche du Centre Hospitalier de l'Université de Montréal, Montreal, QC, Canada.,Department of OBGYN, Université de Montréal, Montreal, QC, Canada
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Goupil A, Nano M, Letort G, Gemble S, Edwards F, Goundiam O, Gogendeau D, Pennetier C, Basto R. Chromosomes function as a barrier to mitotic spindle bipolarity in polyploid cells. J Cell Biol 2020; 219:133854. [PMID: 32328633 PMCID: PMC7147111 DOI: 10.1083/jcb.201908006] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Revised: 12/13/2019] [Accepted: 01/24/2020] [Indexed: 01/22/2023] Open
Abstract
Ploidy variations such as genome doubling are frequent in human tumors and have been associated with genetic instability favoring tumor progression. How polyploid cells deal with increased centrosome numbers and DNA content remains unknown. Using Drosophila neuroblasts and human cancer cells to study mitotic spindle assembly in polyploid cells, we found that most polyploid cells divide in a multipolar manner. We show that even if an initial centrosome clustering step can occur at mitotic entry, the establishment of kinetochore-microtubule attachments leads to spatial chromosome configurations, whereby the final coalescence of supernumerary poles into a bipolar array is inhibited. Using in silico approaches and various spindle and DNA perturbations, we show that chromosomes act as a physical barrier blocking spindle pole coalescence and bipolarity. Importantly, microtubule stabilization suppressed multipolarity by improving both centrosome clustering and pole coalescence. This work identifies inhibitors of bipolar division in polyploid cells and provides a rationale to understand chromosome instability typical of polyploid cancer cells.
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Affiliation(s)
- Alix Goupil
- Institut Curie, Paris Science et Lettres Research University, Centre National de la Recherche Scientifique, Unité Mixte de Recherche UMR144, Biology of Centrosomes and Genetic Instability Laboratory, Paris, France
| | - Maddalena Nano
- Institut Curie, Paris Science et Lettres Research University, Centre National de la Recherche Scientifique, Unité Mixte de Recherche UMR144, Biology of Centrosomes and Genetic Instability Laboratory, Paris, France
| | - Gaëlle Letort
- Center for Interdisciplinary Research in Biology, Collège de France, UMR7241/U1050, Paris, France
| | - Simon Gemble
- Institut Curie, Paris Science et Lettres Research University, Centre National de la Recherche Scientifique, Unité Mixte de Recherche UMR144, Biology of Centrosomes and Genetic Instability Laboratory, Paris, France
| | - Frances Edwards
- Institut Curie, Paris Science et Lettres Research University, Centre National de la Recherche Scientifique, Unité Mixte de Recherche UMR144, Biology of Centrosomes and Genetic Instability Laboratory, Paris, France
| | - Oumou Goundiam
- Institut Curie, Paris Science et Lettres Research University, Centre National de la Recherche Scientifique, Unité Mixte de Recherche UMR144, Biology of Centrosomes and Genetic Instability Laboratory, Paris, France.,Department of Translational Research, Institut Curie, PSL University, Paris, France
| | - Delphine Gogendeau
- Institut Curie, Paris Science et Lettres Research University, Centre National de la Recherche Scientifique, Unité Mixte de Recherche UMR144, Biology of Centrosomes and Genetic Instability Laboratory, Paris, France
| | - Carole Pennetier
- Institut Curie, Paris Science et Lettres Research University, Centre National de la Recherche Scientifique, Unité Mixte de Recherche UMR144, Biology of Centrosomes and Genetic Instability Laboratory, Paris, France
| | - Renata Basto
- Institut Curie, Paris Science et Lettres Research University, Centre National de la Recherche Scientifique, Unité Mixte de Recherche UMR144, Biology of Centrosomes and Genetic Instability Laboratory, Paris, France
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