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Bogolyubova IO, Sailau ZK, Bogolyubov DS. Nuclear Distribution of the Chromatin-Remodeling Protein ATRX in Mouse Early Embryos during Normal Development and Developmental Arrest In Vitro. Life (Basel) 2023; 14:5. [PMID: 38276254 PMCID: PMC10817635 DOI: 10.3390/life14010005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Revised: 12/12/2023] [Accepted: 12/17/2023] [Indexed: 01/27/2024] Open
Abstract
The chromatin-remodeling protein ATRX, which is currently recognized as one of the key genome caretakers, plays an important role in oogenesis and early embryogenesis in mammals. ATRX distribution in the nuclei of mouse embryos developing in vivo and in vitro, including when the embryos are arrested at the two-cell stage-the so-called two-cell block in vitro-was studied using immunofluorescent labeling and FISH. In normally developing two- and four-cell embryos, ATRX was found to be closely colocalized with pericentromeric DNA sequences detected with a probe to the mouse major satellite DNA. The association of ATRX with pericentromeric heterochromatin is mediated by nuclear actin and reduced after the treatment of embryos with latrunculin B. When culturing embryos in vitro, the distribution pattern of ATRX changes, leading to a decrease in the association of this protein with major satellite DNA especially under the two-cell block in vitro. Taken together, our data suggest that the intranuclear distribution of ATRX reflects the viability of mouse embryos and their probability of successful preimplantation development.
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Affiliation(s)
- Irina O. Bogolyubova
- Institute of Cytology of the Russian Academy of Sciences, St. Petersburg 194064, Russia;
| | - Zhuldyz K. Sailau
- PERSONA International Clinical Center for Reproductology, Almaty 050060, Kazakhstan;
| | - Dmitry S. Bogolyubov
- Institute of Cytology of the Russian Academy of Sciences, St. Petersburg 194064, Russia;
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Rana M, Bajaj D, Choubey P, Jain S, Basu-Modak S. Altered Expression of Heme Oxygenase 2 in Heme Oxygenase 1-deficient Mouse Embryos. J Histochem Cytochem 2023; 71:431-450. [PMID: 37480265 PMCID: PMC10424577 DOI: 10.1369/00221554231189310] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Accepted: 06/27/2023] [Indexed: 07/23/2023] Open
Abstract
Heme oxygenases (Hmoxs) are enzymes that catalyze the first and rate-limiting step in the degradation of heme to carbon monoxide, iron, and biliverdin. The two main isozymes, namely Hmox1 and Hmox2, are encoded by two different genes. Mutation of the Hmox1 gene in mice is known to cause extensive prenatal lethality, and limited information is available about the expression of Hmox proteins in developing mouse embryos. In this study, immunohistochemistry was used to perform a detailed investigation comparing Hmox proteins in Hmox1 wild-type and knockout (KO) mouse embryos collected from wild-type and heterozygous timed-matings. Western analysis for Hmoxs was also done in the organs of late-gestation embryos. The results demonstrated cytoplasmic and nuclear localization of Hmoxs in all the organs examined in wild-type embryos. Interestingly, Hmox2 immunoreactive protein signals were significantly low in most of the organs of mid- and late-gestation Hmox1-KO embryos. Furthermore, relative levels of Hmox2 were revealed to be significantly lower in the lung and kidney of late-gestation Hmox1-KO embryos by western analysis, which complemented the immunohistochemistry findings in these two organs. The current study provides detailed immunoexpression patterns of Hmox proteins in wild-type and Hmox1-KO mouse embryos in mid- and late-gestation.
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Affiliation(s)
- Meenakshi Rana
- Department of Zoology, University of Delhi, New Delhi, India
- Department of Zoology, Dyal Singh College, University of Delhi, New Delhi, India
| | - Divya Bajaj
- Department of Zoology, University of Delhi, New Delhi, India
- Department of Zoology, Hindu College, University of Delhi, New Delhi, India
| | - Pooja Choubey
- Department of Zoology, University of Delhi, New Delhi, India
| | - Sidhant Jain
- Department of Zoology, University of Delhi, New Delhi, India
- Institute for Globally Distributed Open Research and Education (IGDORE), Rewari, Haryana, India
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3
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Jiang S, Huang Z, Li Y, Yu C, Yu H, Ke Y, Jiang L, Liu J. Single-cell chromatin accessibility and transcriptome atlas of mouse embryos. Cell Rep 2023; 42:112210. [PMID: 36881507 DOI: 10.1016/j.celrep.2023.112210] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Revised: 11/08/2022] [Accepted: 02/16/2023] [Indexed: 03/08/2023] Open
Abstract
Cis-regulatory elements regulate gene expression and lineage specification. However, the potential regulation of cis-elements on mammalian embryogenesis remains largely unexplored. To address this question, we perform single-cell assay for transposase-accessible chromatin using sequencing (ATAC-seq) and RNA-seq in embryonic day 7.5 (E7.5) and E13.5 mouse embryos. We construct the chromatin accessibility landscapes with cell spatial information in E7.5 embryos, showing the spatial patterns of cis-elements and the spatial distribution of potentially functional transcription factors (TFs). We further show that many germ-layer-specific cis-elements and TFs in E7.5 embryos are maintained in the cell types derived from the corresponding germ layers at later stages, suggesting that these cis-elements and TFs are important during cell differentiation. We also find a potential progenitor for Sertoli and granulosa cells in gonads. Interestingly, both Sertoli and granulosa cells exist in male gonads and female gonads during gonad development. Collectively, we provide a valuable resource to understand organogenesis in mammals.
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Affiliation(s)
- Shan Jiang
- China National Center for Bioinformation, Beijing 100101, China; CAS Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing 100101, China
| | - Zheng Huang
- China National Center for Bioinformation, Beijing 100101, China; CAS Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing 100101, China
| | - Yun Li
- China National Center for Bioinformation, Beijing 100101, China; CAS Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing 100101, China
| | - Chengwei Yu
- China National Center for Bioinformation, Beijing 100101, China; CAS Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing 100101, China; College of Future Technology College, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Hao Yu
- China National Center for Bioinformation, Beijing 100101, China; CAS Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing 100101, China; College of Future Technology College, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yuwen Ke
- College of Biological Science, China Agricultural University, Beijing 100193, China
| | - Lan Jiang
- China National Center for Bioinformation, Beijing 100101, China; CAS Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing 100101, China; College of Future Technology College, University of Chinese Academy of Sciences, Beijing 100049, China; Sino-Danish College, University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Jiang Liu
- China National Center for Bioinformation, Beijing 100101, China; CAS Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing 100101, China; College of Future Technology College, University of Chinese Academy of Sciences, Beijing 100049, China; CAS Center for Excellence in Animal Evolution and Genetics, Chinese Academy of Sciences, Kunming 650223, China.
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Abstract
With the ever-expanding numbers of genetically altered (GA) animals created in this new age of CRISPR/Cas, tools for helping the management of this vast and valuable resource are essential. Cryopreservation of embryos and germplasm of GA animals has been a widely used tool for many years now, allowing for the archiving, distribution and colony management of stock. However, each year brings an array of advances, improving survival rates of embryos, success rates of in-vitro fertilisation and the ability to better share lines and refine the methods to preserve them. This article will focus on the mouse field, referencing the latest developments and assessing their efficacy and ease of implementation, with a brief note on other common genetically altered species (rat, zebrafish, Xenopus, avian species and non-human Primates).
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Uchikura A, Matsunari H, Maehara M, Yonamine S, Wakayama S, Wakayama T, Nagashima H. Hollow fiber vitrification allows cryopreservation of embryos with compromised cryotolerance. Reprod Med Biol 2020; 19:142-150. [PMID: 32273819 PMCID: PMC7138943 DOI: 10.1002/rmb2.12312] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Revised: 11/22/2019] [Accepted: 12/02/2019] [Indexed: 11/12/2022] Open
Abstract
PURPOSE This study aims to demonstrate vitrification methods that provide reliable cryopreservation for embryos with compromised cryotolerance. METHODS Two-cell stage mouse embryos and in vitro produced porcine embryos were vitrified using the hollow fiber vitrification (HFV) and Cryotop (CT) methods. The performance of these two methods was compared by the viability of the vitrified-rewarmed embryos. RESULTS Regardless of the method used, 100% of the mouse 2-cell embryos developed successfully after vitrification-rewarming into the blastocyst stage, whereas vitrification tests using porcine morulae with the HFV method produced significantly better results. The developmental rates of vitrified porcine morula into the blastocyst stage, as well as blastocyst cell number, were 90.3% and 112.3 ± 6.9 in the HFV group compared with 63.4% and 89.5 ± 8.1 in the CT group (P < .05). Vitrification tests using 4- to 8-cell porcine embryos resulted in development into the blastocyst stage (45.5%) in the HFV group alone, demonstrating its better efficacy. The HFV method did not impair embryo viability, even after spontaneous rewarming at room temperature for vitrified embryos, which is generally considered a contraindication. CONCLUSION Vitrification test using embryos with compromised cryotolerance allows for more precise determining of effective cryopreservation methods and devices.
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Affiliation(s)
- Ayuko Uchikura
- Laboratory of Developmental EngineeringDepartment of Life SciencesSchool of AgricultureMeiji UniversityKawasakiJapan
| | - Hitomi Matsunari
- Laboratory of Developmental EngineeringDepartment of Life SciencesSchool of AgricultureMeiji UniversityKawasakiJapan
- Meiji University International Institute for Bio‐Resource Research (MUIIBR)KawasakiJapan
| | - Miki Maehara
- Department of Orthopaedic SurgerySurgical ScienceTokai University School of MedicineIseharaJapan
| | - Shiori Yonamine
- Laboratory of Developmental EngineeringDepartment of Life SciencesSchool of AgricultureMeiji UniversityKawasakiJapan
| | - Sayaka Wakayama
- Department of BiotechnologyFaculty of Life and Environmental SciencesUniversity of YamanashiKohuJapan
| | - Teruhiko Wakayama
- Department of BiotechnologyFaculty of Life and Environmental SciencesUniversity of YamanashiKohuJapan
| | - Hiroshi Nagashima
- Laboratory of Developmental EngineeringDepartment of Life SciencesSchool of AgricultureMeiji UniversityKawasakiJapan
- Meiji University International Institute for Bio‐Resource Research (MUIIBR)KawasakiJapan
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Niwayama R, Moghe P, Liu YJ, Fabrèges D, Buchholz F, Piel M, Hiiragi T. A Tug-of-War between Cell Shape and Polarity Controls Division Orientation to Ensure Robust Patterning in the Mouse Blastocyst. Dev Cell 2019; 51:564-574.e6. [PMID: 31735668 PMCID: PMC6892278 DOI: 10.1016/j.devcel.2019.10.012] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2019] [Revised: 07/04/2019] [Accepted: 10/14/2019] [Indexed: 01/08/2023]
Abstract
Oriented cell division patterns tissues by modulating cell position and fate. While cell geometry, junctions, cortical tension, and polarity are known to control division orientation, relatively little is known about how these are coordinated to ensure robust patterning. Here, we systematically characterize cell division, volume, and shape changes during mouse pre-implantation development by in toto live imaging. The analysis leads us to a model in which the apical domain competes with cell shape to determine division orientation. Two key predictions of the model are verified experimentally: when outside cells of the 16-cell embryo are released from cell shape asymmetry, the axis of division is guided by the apical domain. Conversely, orientation cues from the apical domain can be overcome by applied shape asymmetry in the 8-cell embryo. We propose that such interplay between cell shape and polarity in controlling division orientation ensures robust patterning of the blastocyst and possibly other tissues. Cell division, volume, and shape changes are characterized by in toto embryo imaging Cell shape and the apical domain compete to determine division orientation Two key predictions of the model are verified experimentally The tug-of-war mechanism ensures robust cell allocation and patterning
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Affiliation(s)
- Ritsuya Niwayama
- European Molecular Biology Laboratory (EMBL), Heidelberg, Germany
| | - Prachiti Moghe
- European Molecular Biology Laboratory (EMBL), Heidelberg, Germany
| | - Yan-Jun Liu
- UMR 144 Institut Curie, Institut Pierre Gilles de Gennes for Microfluidics, Paris, France
| | - Dimitri Fabrèges
- European Molecular Biology Laboratory (EMBL), Heidelberg, Germany
| | - Frank Buchholz
- Medical Systems Biology, UCC, University Hospital and Medical Faculty Carl Gustav Carus, TU Dresden, Dresden, Germany
| | - Matthieu Piel
- UMR 144 Institut Curie, Institut Pierre Gilles de Gennes for Microfluidics, Paris, France
| | - Takashi Hiiragi
- European Molecular Biology Laboratory (EMBL), Heidelberg, Germany; Institute for Advanced Study of Human Biology (WPI-ASHBi), Kyoto University, Kyoto, Japan.
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Kobayashi M, Tarnawsky SP, Wei H, Mishra A, Azevedo Portilho N, Wenzel P, Davis B, Wu J, Hadland B, Yoshimoto M. Hemogenic Endothelial Cells Can Transition to Hematopoietic Stem Cells through a B-1 Lymphocyte-Biased State during Maturation in the Mouse Embryo. Stem Cell Reports 2019; 13:21-30. [PMID: 31231025 PMCID: PMC6626887 DOI: 10.1016/j.stemcr.2019.05.025] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2019] [Revised: 05/24/2019] [Accepted: 05/24/2019] [Indexed: 11/27/2022] Open
Abstract
Precursors of hematopoietic stem cells (pre-HSCs) have been identified as intermediate precursors during the maturation process from hemogenic endothelial cells to HSCs in the aorta-gonad-mesonephros (AGM) region of the mouse embryo at embryonic day 10.5. Although pre-HSCs acquire an efficient adult-repopulating ability after ex vivo co-culture, their native hematopoietic capacity remains unknown. Here, we employed direct transplantation assays of CD45-VE-cadherin(VC)+KIT+(V+K+) cells (containing pre-HSCs) into immunodeficient neonatal mice that permit engraftment of embryonic hematopoietic precursors. We found that freshly isolated V+K+ cells exhibited significantly greater B-1 lymphocyte-biased repopulating capacity than multilineage repopulating capacity. Additionally, B cell colony-forming assays demonstrated the predominant B-1 progenitor colony-forming ability of these cells; however, increased B-2 progenitor colony-forming ability emerged after co-culture with Akt-expressing AGM endothelial cells, conditions that support pre-HSC maturation into HSCs. Our studies revealed an unexpected B-1 lymphocyte bias of the V+K+ population and acquisition of B-2 potential during commitment to the HSC fate.
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Affiliation(s)
- Michihiro Kobayashi
- Center for Stem Cell and Regenerative Medicine, Institute of Molecular Medicine, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Stefan P Tarnawsky
- Wells Center for Pediatric Research, Department of Pediatrics, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Haichao Wei
- Center for Stem Cell and Regenerative Medicine, Institute of Molecular Medicine, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Akansha Mishra
- Wells Center for Pediatric Research, Department of Pediatrics, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Nathalia Azevedo Portilho
- Center for Stem Cell and Regenerative Medicine, Institute of Molecular Medicine, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Pamela Wenzel
- Center for Stem Cell and Regenerative Medicine, Institute of Molecular Medicine, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Brian Davis
- Center for Stem Cell and Regenerative Medicine, Institute of Molecular Medicine, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Jiaqian Wu
- Center for Stem Cell and Regenerative Medicine, Institute of Molecular Medicine, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Brandon Hadland
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA; Department of Pediatrics, Division of Pediatric Hematology/Oncology, University of Washington School of Medicine, Seattle, WA 98105, USA
| | - Momoko Yoshimoto
- Center for Stem Cell and Regenerative Medicine, Institute of Molecular Medicine, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX 77030, USA.
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Vivancos Stalin L, Gualandi M, Schulte JH, Renella R, Shakhova O, Mühlethaler-Mottet A. Expression of the Neuroblastoma-Associated ALK-F1174L Activating Mutation During Embryogenesis Impairs the Differentiation of Neural Crest Progenitors in Sympathetic Ganglia. Front Oncol 2019; 9:275. [PMID: 31058082 PMCID: PMC6477091 DOI: 10.3389/fonc.2019.00275] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Accepted: 03/25/2019] [Indexed: 12/28/2022] Open
Abstract
Neuroblastoma (NB) is an embryonal malignancy derived from the abnormal differentiation of the sympathetic nervous system. The Anaplastic Lymphoma Kinase (ALK) gene is frequently altered in NB, through copy number alterations and activating mutations, and represents a predisposition in NB-genesis when mutated. Our previously published data suggested that ALK activating mutations may impair the differentiation potential of neural crest (NC) progenitor cells. Here, we demonstrated that the expression of the endogenous ALK gene starts at E10.5 in the developing sympathetic ganglia (SG). To decipher the impact of deregulated ALK signaling during embryogenesis on the formation and differentiation of sympathetic neuroblasts, Sox10-Cre;LSL-ALK-F1174L embryos were produced to restrict the expression of the human ALK-F1174L transgene to migrating NC cells (NCCs). First, ALK-F1174L mediated an embryonic lethality at mid-gestation and an enlargement of SG with a disorganized architecture in Sox10-Cre;LSL-ALK-F1174L embryos at E10.5 and E11.5. Second, early sympathetic differentiation was severely impaired in Sox10-Cre;LSL-ALK-F1174L embryos. Indeed, their SG displayed a marked increase in the proportion of NCCs and a decrease of sympathetic neuroblasts at both embryonic stages. Third, neuronal and noradrenergic differentiations were blocked in Sox10-Cre;LSL-ALK-F1174L SG, as a reduced proportion of Phox2b+ sympathoblasts expressed βIII-tubulin and almost none were Tyrosine Hydroxylase (TH) positive. Finally, at E10.5, ALK-F1174L mediated an important increase in the proliferation of Phox2b+ progenitors, affecting the transient cell cycle exit observed in normal SG at this embryonic stage. Altogether, we report for the first time that the expression of the human ALK-F1174L mutation in NCCs during embryonic development profoundly disturbs early sympathetic progenitor differentiation, in addition to increasing their proliferation, both mechanisms being potential crucial events in NB oncogenesis.
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Affiliation(s)
- Lucie Vivancos Stalin
- Pediatric Hematology-Oncology Research Laboratory, DFME, University Hospital of Lausanne, CHUV-UNIL, Lausanne, Switzerland
| | - Marco Gualandi
- Translational Oncology, Department of Hematology and Oncology, University Hospital Zürich, Zurich, Switzerland
| | - Johannes Hubertus Schulte
- Department of Pediatric Hematology, Oncology and SCT, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany.,Berlin Institute of Health Berlin, Germany.,German Cancer Consortium, Partner Site Berlin and German Cancer Research Center, Heidelberg, Germany
| | - Raffaele Renella
- Pediatric Hematology-Oncology Research Laboratory, DFME, University Hospital of Lausanne, CHUV-UNIL, Lausanne, Switzerland
| | - Olga Shakhova
- Translational Oncology, Department of Hematology and Oncology, University Hospital Zürich, Zurich, Switzerland
| | - Annick Mühlethaler-Mottet
- Pediatric Hematology-Oncology Research Laboratory, DFME, University Hospital of Lausanne, CHUV-UNIL, Lausanne, Switzerland
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Liang P, Sun H, Sun Y, Zhang X, Xie X, Zhang J, Zhang Z, Chen Y, Ding C, Xiong Y, Ma W, Liu D, Huang J, Songyang Z. Effective gene editing by high-fidelity base editor 2 in mouse zygotes. Protein Cell 2017; 8:601-611. [PMID: 28585179 PMCID: PMC5546933 DOI: 10.1007/s13238-017-0418-2] [Citation(s) in RCA: 63] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2017] [Accepted: 04/29/2017] [Indexed: 12/02/2022] Open
Abstract
Targeted point mutagenesis through homologous recombination has been widely used in genetic studies and holds considerable promise for repairing disease-causing mutations in patients. However, problems such as mosaicism and low mutagenesis efficiency continue to pose challenges to clinical application of such approaches. Recently, a base editor (BE) system built on cytidine (C) deaminase and CRISPR/Cas9 technology was developed as an alternative method for targeted point mutagenesis in plant, yeast, and human cells. Base editors convert C in the deamination window to thymidine (T) efficiently, however, it remains unclear whether targeted base editing in mouse embryos is feasible. In this report, we generated a modified high-fidelity version of base editor 2 (HF2-BE2), and investigated its base editing efficacy in mouse embryos. We found that HF2-BE2 could convert C to T efficiently, with up to 100% biallelic mutation efficiency in mouse embryos. Unlike BE3, HF2-BE2 could convert C to T on both the target and non-target strand, expanding the editing scope of base editors. Surprisingly, we found HF2-BE2 could also deaminate C that was proximal to the gRNA-binding region. Taken together, our work demonstrates the feasibility of generating point mutations in mouse by base editing, and underscores the need to carefully optimize base editing systems in order to eliminate proximal-site deamination.
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Affiliation(s)
- Puping Liang
- Key Laboratory of Gene Engineering of the Ministry of Education, Guangzhou Key Laboratory of Healthy Aging Research and State Key Laboratory of Biocontrol, SYSU-BCM Joint Research Center, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, China.
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, 510275, China.
- Key Laboratory of Reproductive Medicine of Guangdong Province, School of Life Sciences and the First Affiliated Hospital, Sun Yat-sen University, Guangzhou, 510275, China.
| | - Hongwei Sun
- Key Laboratory of Gene Engineering of the Ministry of Education, Guangzhou Key Laboratory of Healthy Aging Research and State Key Laboratory of Biocontrol, SYSU-BCM Joint Research Center, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, China
| | - Ying Sun
- Key Laboratory of Gene Engineering of the Ministry of Education, Guangzhou Key Laboratory of Healthy Aging Research and State Key Laboratory of Biocontrol, SYSU-BCM Joint Research Center, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, China
| | - Xiya Zhang
- Key Laboratory of Gene Engineering of the Ministry of Education, Guangzhou Key Laboratory of Healthy Aging Research and State Key Laboratory of Biocontrol, SYSU-BCM Joint Research Center, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, China
| | - Xiaowei Xie
- Key Laboratory of Gene Engineering of the Ministry of Education, Guangzhou Key Laboratory of Healthy Aging Research and State Key Laboratory of Biocontrol, SYSU-BCM Joint Research Center, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, China
| | - Jinran Zhang
- Key Laboratory of Gene Engineering of the Ministry of Education, Guangzhou Key Laboratory of Healthy Aging Research and State Key Laboratory of Biocontrol, SYSU-BCM Joint Research Center, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, China
| | - Zhen Zhang
- Key Laboratory of Gene Engineering of the Ministry of Education, Guangzhou Key Laboratory of Healthy Aging Research and State Key Laboratory of Biocontrol, SYSU-BCM Joint Research Center, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, China
- Guangzhou Magigen Biotechnology Co.Ltd, Guangzhou, 510320, China
| | - Yuxi Chen
- Key Laboratory of Gene Engineering of the Ministry of Education, Guangzhou Key Laboratory of Healthy Aging Research and State Key Laboratory of Biocontrol, SYSU-BCM Joint Research Center, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, China
| | - Chenhui Ding
- Key Laboratory of Reproductive Medicine of Guangdong Province, School of Life Sciences and the First Affiliated Hospital, Sun Yat-sen University, Guangzhou, 510275, China
| | - Yuanyan Xiong
- Key Laboratory of Gene Engineering of the Ministry of Education, Guangzhou Key Laboratory of Healthy Aging Research and State Key Laboratory of Biocontrol, SYSU-BCM Joint Research Center, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, China
| | - Wenbin Ma
- Key Laboratory of Gene Engineering of the Ministry of Education, Guangzhou Key Laboratory of Healthy Aging Research and State Key Laboratory of Biocontrol, SYSU-BCM Joint Research Center, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, China
| | - Dan Liu
- Verna and Marrs Mclean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, One Baylor Plaza, Houston, TX, 77030, USA
| | - Junjiu Huang
- Key Laboratory of Gene Engineering of the Ministry of Education, Guangzhou Key Laboratory of Healthy Aging Research and State Key Laboratory of Biocontrol, SYSU-BCM Joint Research Center, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, China.
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, 510275, China.
| | - Zhou Songyang
- Key Laboratory of Gene Engineering of the Ministry of Education, Guangzhou Key Laboratory of Healthy Aging Research and State Key Laboratory of Biocontrol, SYSU-BCM Joint Research Center, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, China.
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, 510275, China.
- Key Laboratory of Reproductive Medicine of Guangdong Province, School of Life Sciences and the First Affiliated Hospital, Sun Yat-sen University, Guangzhou, 510275, China.
- Verna and Marrs Mclean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, One Baylor Plaza, Houston, TX, 77030, USA.
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10
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Xu M, Zhu X, Yu J, Yu J, Luo S, Wang X. The crystal structure of Ac-AChBP in complex with α-conotoxin LvIA reveals the mechanism of its selectivity towards different nAChR subtypes. Protein Cell 2017; 8:675-685. [PMID: 28585176 PMCID: PMC5563285 DOI: 10.1007/s13238-017-0426-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Accepted: 04/27/2017] [Indexed: 12/15/2022] Open
Abstract
The α3* nAChRs, which are considered to be promising drug targets for problems such as pain, addiction, cardiovascular function, cognitive disorders etc., are found throughout the central and peripheral nervous system. The α-conotoxin (α-CTx) LvIA has been identified as the most selective inhibitor of α3β2 nAChRs known to date, and it can distinguish the α3β2 nAChR subtype from the α6/α3β2β3 and α3β4 nAChR subtypes. However, the mechanism of its selectivity towards α3β2, α6/α3β2β3, and α3β4 nAChRs remains elusive. Here we report the co-crystal structure of LvIA in complex with Aplysia californica acetylcholine binding protein (Ac-AChBP) at a resolution of 3.4 Å. Based on the structure of this complex, together with homology modeling based on other nAChR subtypes and binding affinity assays, we conclude that Asp-11 of LvIA plays an important role in the selectivity of LvIA towards α3β2 and α3/α6β2β3 nAChRs by making a salt bridge with Lys-155 of the rat α3 subunit. Asn-9 lies within a hydrophobic pocket that is formed by Met-36, Thr-59, and Phe-119 of the rat β2 subunit in the α3β2 nAChR model, revealing the reason for its more potent selectivity towards the α3β2 nAChR subtype. These results provide molecular insights that can be used to design ligands that selectively target α3β2 nAChRs, with significant implications for the design of new therapeutic α-CTxs.
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Affiliation(s)
- Manyu Xu
- The Ministry of Education Key Laboratory of Protein Science, School of Life Sciences, Beijing Advanced Innovation Center for Structural Biology, Collaborative Innovation Center for Biotherapy, Tsinghua University, Beijing, 100084, China
| | - Xiaopeng Zhu
- Key Laboratory of Tropical Biological Resources, Ministry of Education, Key Lab for Marine Drugs of Haikou, Hainan University, Haikou, 570228, China
| | - Jinfang Yu
- The Ministry of Education Key Laboratory of Protein Science, School of Life Sciences, Beijing Advanced Innovation Center for Structural Biology, Collaborative Innovation Center for Biotherapy, Tsinghua University, Beijing, 100084, China
| | - Jinpeng Yu
- Key Laboratory of Tropical Biological Resources, Ministry of Education, Key Lab for Marine Drugs of Haikou, Hainan University, Haikou, 570228, China
| | - Sulan Luo
- Key Laboratory of Tropical Biological Resources, Ministry of Education, Key Lab for Marine Drugs of Haikou, Hainan University, Haikou, 570228, China.
| | - Xinquan Wang
- The Ministry of Education Key Laboratory of Protein Science, School of Life Sciences, Beijing Advanced Innovation Center for Structural Biology, Collaborative Innovation Center for Biotherapy, Tsinghua University, Beijing, 100084, China.
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11
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Hu Y, Huang Y, Yi Y, Wang H, Liu B, Yu J, Wang D. Single-cell RNA sequencing highlights transcription activity of autophagy-related genes during hematopoietic stem cell formation in mouse embryos. Autophagy 2017; 13:770-771. [PMID: 28129010 DOI: 10.1080/15548627.2016.1278093] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Abstract
Accumulating evidence has demonstrated that macroautophagy/autophagy plays an essential role in self-renewal and differentiation in embryonic hematopoiesis. Here, according to the RNA sequencing data sets of 5 population cells related to hematopoietic stem cell (HSC) formation during mouse embryogenesis (endothelial cells, PTPRC/CD45- and PTPRC/CD45+ pre-HSCs in the E11 aorta-gonad-mesonephros (AGM) region, mature HSCs in E12 and E14 fetal liver), we explored the dynamic expression of mouse autophagy-related genes in this course at the single-cell level. Our results revealed that the transcription activity of autophagy-related genes had a substantial increase when endothelial cells (ECs) specified into pre-HSCs, and the upregulation of autophagy-essential genes correlated with reduced NOTCH signaling in pre-HSCs, suggesting the autophagy activity may be greatly enhanced during pre-HSC specification from endothelial precursors. In summary, our results presented strong evidence that autophagy plays a critical role in HSC emergence during mouse midgestation.
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Affiliation(s)
- Yongfei Hu
- a College of Bioinformatics Science and Technology , Harbin Medical University , Harbin , China
| | - Yan Huang
- a College of Bioinformatics Science and Technology , Harbin Medical University , Harbin , China
| | - Ying Yi
- a College of Bioinformatics Science and Technology , Harbin Medical University , Harbin , China
| | - Hongwei Wang
- a College of Bioinformatics Science and Technology , Harbin Medical University , Harbin , China
| | - Bing Liu
- b 307-Ivy Translational Medicine Center , Laboratory of Oncology, Affiliated Hospital, Academy of Military Medical Sciences , Beijing , China
| | - Jia Yu
- c Department of Biochemistry and Molecular Biology , School of Basic Sciences and Institute of Basic Medical Sciences, Peking Union Medical College & Chinese Academy of Medical Sciences , Beijing , China
| | - Dong Wang
- a College of Bioinformatics Science and Technology , Harbin Medical University , Harbin , China.,d Training Center for Students Innovation and Entrepreneurship Education, Harbin Medical University , Harbin , China
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12
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Somoskői B, Kovács M, Cseh S. T-2 mycotoxin slows down the development of mouse blastocysts, decreases their blastomere number and increases chromatin damage. Acta Vet Hung 2016; 64:390-400. [PMID: 27653435 DOI: 10.1556/004.2016.037] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The mycotoxin T-2 has many harmful effects on mammalian cells and reproductive functions. In the present study, the in vitro effect of T-2 toxin on mouse blastocysts was examined. Embryos were cultured in media supplemented with 0.5, 0.75 and 1 ng/ml T-2. Different exposure times were applied [96 h (treatment I) or 24 h following 72 h in toxin-free media (treatment II)]. Blastomere number, nuclear chromatin status and blastocoel formation were investigated in blastocysts. Our data show that the effect of T-2 toxin may vary depending on the stage of the embryo at the start of exposure. At 96 h of exposure, the blastocysts had blastomeres with normal chromatin quality but their developmental potential was decreased. After 24 h of exposure applied following a 72-h culture, blastomeres had a higher level of chromatin damage, although their developmental potential was the same as in the control embryos. In both cases, decreased mitotic rate was found, which resulted in decreased blastomere number even at low toxin concentration.
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Affiliation(s)
- Bence Somoskői
- 1Department and Clinic of Reproduction, University of Veterinary Medicine, István u. 2, H-1078 Budapest, Hungary
| | - Melinda Kovács
- 2 MTA-KE Mycotoxins in the Food Chain Research Group, Kaposvár, Hungary
| | - Sándor Cseh
- 1Department and Clinic of Reproduction, University of Veterinary Medicine, István u. 2, H-1078 Budapest, Hungary
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13
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Enkhmandakh B, Stoddard C, Mack K, He W, Kaback D, Yee SP, Bayarsaihan D. Generation of a mouse model for a conditional inactivation of Gtf2i allele. Genesis 2016; 54:407-12. [PMID: 27194223 DOI: 10.1002/dvg.22948] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2016] [Revised: 05/15/2016] [Accepted: 05/16/2016] [Indexed: 01/10/2023]
Abstract
The multifunctional transcription factor TFII-I encoded by the Gtf2i gene is expressed at the two-cell stage, inner cell mass, trophectoderm, and early gastrula stages of the mouse embryo. In embryonic stem cells, TFII-I colocalizes with bivalent domains and depletion of Gtf2i causes embryonic lethality, neural tube closure, and craniofacial defects. To gain insight into the function of TFII-I during late embryonic and postnatal stages, we have generated a conditional Gtf2i null allele by flanking exon 3 with loxP sites. Crossing the floxed line with the Hprt-Cre transgenic mice resulted in inactivation of Gtf2i in one-cell embryo. The Cre-mediated deletion of exon 3 recapitulates a genetic null phenotype, indicating that the conditional Gtf2i line is a valuable tool for studying TFII-I function during embryonic development. genesis 54:407-412, 2016. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Badam Enkhmandakh
- Center for Regenerative Medicine and Skeletal Development, Department of Reconstructive Sciences, University of Connecticut Health Center, Farmington, Connecticut
| | - Chris Stoddard
- Gene Targeting and Transgenic Facility, University of Connecticut Health Center, Farmington, Connecticut
| | - Kris Mack
- Gene Targeting and Transgenic Facility, University of Connecticut Health Center, Farmington, Connecticut
| | - Wei He
- Gene Targeting and Transgenic Facility, University of Connecticut Health Center, Farmington, Connecticut
| | - Deb Kaback
- Gene Targeting and Transgenic Facility, University of Connecticut Health Center, Farmington, Connecticut
| | - Siu-Pok Yee
- Gene Targeting and Transgenic Facility, University of Connecticut Health Center, Farmington, Connecticut
| | - Dashzeveg Bayarsaihan
- Center for Regenerative Medicine and Skeletal Development, Department of Reconstructive Sciences, University of Connecticut Health Center, Farmington, Connecticut
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14
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Somoskoi B, Martino NA, Cardone RA, Lacalandra GM, Dell'Aquila ME, Cseh S. Different chromatin and energy/redox responses of mouse morulae and blastocysts to slow freezing and vitrification. Reprod Biol Endocrinol 2015; 13:22. [PMID: 25889099 PMCID: PMC4419566 DOI: 10.1186/s12958-015-0018-z] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/08/2014] [Accepted: 03/09/2015] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The ability to cryopreserve mammalian embryos has become an integral part of assisted reproduction, both in human and veterinary medicine. Despite differences in the size and physiological characteristics of embryos from various species, the embryos have been frozen by either of two procedures: slow freezing or vitrification. The aim of our study was to compare the effect of slow freezing and vitrification to the chromatin structure, energy status and reactive oxygen species production of mouse morulae and blastocysts. METHODS Mouse morulae and blastocysts were randomly allocated into vitrification, slow freezing and control groups. For slow freezing, Dulbecco phosphate buffered saline based 10% glicerol solution was used. For vitrification, G-MOPS™ based solution supplemented with 16% ethylene glycol, 16% propylene glycol, Ficoll (10 mg/ml) and sucrose (0.65 mol/l) was used. After warming, the chromatin integrity, mitochondrial distribution pattern and energy/oxidative status were compared among groups. RESULTS Cryopreservation affected chromatin integrity at a greater extent at the morula than the blastocyst stage. Chromatin damage induced by slow freezing was more relevant compared to vitrification. Slow freezing and vitrification similarly affected mitochondrial distribution pattern. Greater damage was observed at the morula stage and it was associated with embryo grade. Cryopreservation altered the quantitative bioenergy/redox parameters at a greater extent in the morulae than in the blastocysts. Effects induced by slow freezing were not related to embryo grade or mitochondrial pattern, as affected embryos were of all grades and with both mitochondrial patterns. However, effects induced by vitrification were related to mitochondrial pattern, as only embryos with homogeneous mitochondrial pattern in small aggregates had reduced energy status. CONCLUSIONS This study shows for the first time the joint assessment of chromatin damage and mitochondrial energy/redox potential in fresh and frozen mouse embryos at the morula and blastocyst stage, allowing the comparison of the effects of the two most commonly used cryopreservation procedures.
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Affiliation(s)
- Bence Somoskoi
- Department and Clinic of Obstetrics and Reproduction, Szent Istvan University, Budapest, Hungary.
| | - Nicola A Martino
- Veterinary Clinics and Animal Productions Unit, Department of Emergency and Organ Trasplantation (DETO), University of Bari Aldo Moro Valenzano, Bari, Italy.
| | - Rosa A Cardone
- Department of Bioscience, Biotechnology and Pharmacological Science, University of Bari, 70126, Bari, Italy.
| | - Giovanni M Lacalandra
- Veterinary Clinics and Animal Productions Unit, Department of Emergency and Organ Trasplantation (DETO), University of Bari Aldo Moro Valenzano, Bari, Italy.
| | - Maria E Dell'Aquila
- Department of Bioscience, Biotechnology and Pharmacological Science, University of Bari, 70126, Bari, Italy.
| | - Sandor Cseh
- Department and Clinic of Obstetrics and Reproduction, Szent Istvan University, Budapest, Hungary.
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15
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Larin KV, Larina IV, Liebling M, Dickinson ME. Live Imaging of Early Developmental Processes in Mammalian Embryos with Optical Coherence Tomography. J Innov Opt Health Sci 2009; 2:253-259. [PMID: 20582330 PMCID: PMC2891056 DOI: 10.1142/s1793545809000619] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Early embryonic imaging of cardiovascular development in mammalian models requires a method that can penetrate through and distinguish the many tissue layers with high spatial and temporal resolution. In this paper we evaluate the capability of Optical Coherence Tomography (OCT) technique for structural 3D embryonic imaging in mouse embryos at different stages of the developmental process ranging from 7.5 dpc up to 10.5 dpc. Obtained results suggest that the collected data is suitable for quantitative and qualitative measurements to assess cardiovascular function in mouse models, which is likely to expand our knowledge of the complexity of the embryonic heart, and its development into an adult heart.
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Affiliation(s)
- Kirill V. Larin
- Department of Biomedical Engineering, University of Houston, Houston, TX, USA
| | - Irina V. Larina
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, TX, USA
| | - Michael Liebling
- Department of Electrical and Computer Engineering, University of California, Santa Barbara, CA, USA
| | - Mary E. Dickinson
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, TX, USA
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Abstract
PURPOSE The purpose of this study was to determine the developmental potential of two-cell mouse embryos resulting from vitrification could increased using monolayer of Vero cells. METHODS Two-cell mouse embryos were divided into vitrified and nonvitrified groups. Embryos in the vitrified group were frozen with a combination of 10% ethylene glycol, 30% ficoll, and 0.5% M sucrose (EFS10) as cryoprotectants, and thawed rapidly with 0.5 M sucrose. The survived embryos were cultured either with Vero cells monolayer or in T6 medium. Accordingly the embryos of the nonvitrified group were also cultured. The rates of the development in all the groups were daily determined and statistically compared. At the end of the cultivation period, several expanded blastocysts from each group were stained with ethidium bromide and the mean number of the blastomers were counted and statistically compared. RESULTS After 4 days of culture, the developmental potential of vitrified-thawed embryos were significantly reduced in Vero cell-free medium, and the mean cell number of embryos reaching the expanded blastocyst stage were also lower than that of nonvitrified embryos. With exception of last day of culture, Vero cell coculture, resulted in a significant increase in the rate of development of vitrified-thawed embryos as well as improved the mean cell number of expanded blastocysts. On the other hand, the mean cell number of expanded blastocysts of nonvitrified group was significantly improved in coculture group. However, the rate of embryo development except for the first day of culture was similar to that of medium alone. CONCLUSIONS The developmental potential of vitrified-thawed embryos appears to be retarded in conventional medium and Vero cell monolayer is capable to eliminate the postthaw deleterious effect of vitrification during the first 3 days of cultivation, but not for a longer period.
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Abstract
PURPOSE Our purpose was to evaluate the beneficial effects of long-term coculture of Vero cells on the development of frozen-thawed two-cell mouse embryos. METHODS Two-cell mouse embryos were frozen slowly with 1,2-propandiol and sucrose as cryoprotectants and thawed rapidly, followed by stepwise dilution. Vero cells were cultured in drops of RPMI 1640 to establish monolayers. Frozen-thawed embryos were cultured alone (control) or cocultured with Vero cells. The rate of development in both groups was compared. RESULTS After 4 days of culture, significantly more embryos in coculture were developed to expanded blastocysts (61 vs 37% for controls; P < or = 0.0001). In addition, on the fifth day of cultivation, more embryos in coculture showed the potential of hatching from the zona pellucida (26 vs 7% in controls; P < or = 0.0001). The rate of degeneration in coculture was also much lower than in controls (6 and 15%, respectively). CONCLUSIONS Coculture of cryopreserved preimplantation-stage embryos with Vero cells seems to be a useful tool to eliminate the postthaw deleterious effect of freezing and also to obtain better-quality embryos appropriate for transfer.
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Affiliation(s)
- N Nematollahi
- Department of Anatomy, Kerman University of Medical Sciences, Iran
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18
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Abstract
Programmed methylation and demethylation of regulatory sequences has been proposed to play a central role in vertebrate development. We report here that the methylation status of the 5' regions of a panel of tissue-specific genes could not be correlated with expression in tissues of fetal and newborn mice. Genes reported to be regulated by reversible methylation were not expressed ectopically or precociously in Dnmt1-deficient mouse embryos under conditions where demethylation caused biallelic expression of imprinted genes and activated transcription of endogenous retroviruses of the IAP class. These and other data suggest that the numerous published expression-methylation correlations may have described not a cause but a consequence of transcriptional activation. A model is proposed under which cytosine methylation represents a biochemical specialization of large genomes that participates in specialized biological functions such as allele-specific gene expression and the heritable transcriptional silencing of parasitic sequence elements, whereas cellular differentiation is controlled by conserved regulatory networks that do not depend on covalent modification of the genome.
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Affiliation(s)
- C P Walsh
- Department of Genetics and Development, College of Physicians and Surgeons of Columbia University, New York, New York 10032, USA
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Ma S, Kalousek DK, Yuen BH, Moon YS. Investigation of effects of pregnant mare serum gonadotropin (PMSG) on the chromosomal complement of CD-1 mouse embryos. J Assist Reprod Genet 1997; 14:162-9. [PMID: 9090560 PMCID: PMC3454672 DOI: 10.1007/bf02766134] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
PURPOSE The objective of this study was to examine the effect of superovulatory doses of gonadotropins on the frequency of chromosomal abnormalities of mouse embryos. METHODS Chromosome analysis of 8- to 16-cell stage mouse embryos and zygotes was performed by a cytogenetic method. RESULTS There was no significant effect of the pregnant mare serum gonadotropin (PMSG) dose on the level of aneuploidy and structural abnormalities from 8- to 16-cell-stage embryos among superovulated groups. However, a simple dose-response relationship between the PMSG dose and the incidence of polyploidy was observed, with the level of polyploidy rising from 2.9% with 10 i.u. PMSG to 10.5% with 15 i.u. PMSG. In zygote stage, the proportion of polyploid embryos also increased as the dose increased, from 1.9% in 5 i.u. to 6.7% in 15 i.u. PMSG. It was observed that the extra chromosomal set in polyploidy embryos originated by both fertilization of a diploid oocyte and dispermy. CONCLUSIONS These results indicate a dose-response relationship between the PMSG dose and the incidence of polyploidy in the CD-1 mouse. Both a disturbance at maturation division and an error at fertilization were the cause of polyploidy.
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Affiliation(s)
- S Ma
- Department of Obstetrics and Gynecology, University of British Columbia, Vancouver, Canada
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