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Kawasumi-Kita A, Lee SW, Ohtsuka D, Niimi K, Asakura Y, Kitajima K, Sakane Y, Tamura K, Ochi H, Suzuki KIT, Morishita Y. hoxc12/c13 as key regulators for rebooting the developmental program in Xenopus limb regeneration. Nat Commun 2024; 15:3340. [PMID: 38649703 PMCID: PMC11035627 DOI: 10.1038/s41467-024-47093-y] [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: 10/27/2022] [Accepted: 03/15/2024] [Indexed: 04/25/2024] Open
Abstract
During organ regeneration, after the initial responses to injury, gene expression patterns similar to those in normal development are reestablished during subsequent morphogenesis phases. This supports the idea that regeneration recapitulates development and predicts the existence of genes that reboot the developmental program after the initial responses. However, such rebooting mechanisms are largely unknown. Here, we explore core rebooting factors that operate during Xenopus limb regeneration. Transcriptomic analysis of larval limb blastema reveals that hoxc12/c13 show the highest regeneration specificity in expression. Knocking out each of them through genome editing inhibits cell proliferation and expression of a group of genes that are essential for development, resulting in autopod regeneration failure, while limb development and initial blastema formation are not affected. Furthermore, the induction of hoxc12/c13 expression partially restores froglet regenerative capacity which is normally very limited compared to larval regeneration. Thus, we demonstrate the existence of genes that have a profound impact alone on rebooting of the developmental program in a regeneration-specific manner.
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Affiliation(s)
- Aiko Kawasumi-Kita
- Laboratory for Developmental Morphogeometry, RIKEN Center for Biosystems Dynamics Research, Kobe, 650-0047, Japan
| | - Sang-Woo Lee
- Laboratory for Developmental Morphogeometry, RIKEN Center for Biosystems Dynamics Research, Kobe, 650-0047, Japan
| | - Daisuke Ohtsuka
- Laboratory for Developmental Morphogeometry, RIKEN Center for Biosystems Dynamics Research, Kobe, 650-0047, Japan
| | - Kaori Niimi
- Laboratory for Developmental Morphogeometry, RIKEN Center for Biosystems Dynamics Research, Kobe, 650-0047, Japan
| | - Yoshifumi Asakura
- Laboratory for Developmental Morphogeometry, RIKEN Center for Biosystems Dynamics Research, Kobe, 650-0047, Japan
| | - Keiichi Kitajima
- Laboratory for Developmental Morphogeometry, RIKEN Center for Biosystems Dynamics Research, Kobe, 650-0047, Japan
- Department of Ecological Developmental Adaptability Life Sciences, Graduate School of Life Sciences, Tohoku University, Sendai, 980-8578, Japan
| | - Yuto Sakane
- Graduate School of Science, Hiroshima University, Higashihiroshima, Hiroshima, 739-8526, Japan
| | - Koji Tamura
- Department of Ecological Developmental Adaptability Life Sciences, Graduate School of Life Sciences, Tohoku University, Sendai, 980-8578, Japan
| | - Haruki Ochi
- Institute for Promotion of Medical Science Research, Faculty of Medicine, Yamagata University, 2-2-2 Iida-Nishi, Yamagata, 990-9585, Japan
| | - Ken-Ichi T Suzuki
- Graduate School of Science, Hiroshima University, Higashihiroshima, Hiroshima, 739-8526, Japan
- Emerging Model Organisms Facility, Trans-scale Biology Center, National Institute for Basic Biology, National Institutes of Natural Sciences, Okazaki, Aichi, 444-8585, Japan
| | - Yoshihiro Morishita
- Laboratory for Developmental Morphogeometry, RIKEN Center for Biosystems Dynamics Research, Kobe, 650-0047, Japan.
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2
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Mochii M, Akizuki K, Ossaka H, Kagawa N, Umesono Y, Suzuki KIT. A CRISPR-Cas9-mediated versatile method for targeted integration of a fluorescent protein gene to visualize endogenous gene expression in Xenopus laevis. Dev Biol 2024; 506:42-51. [PMID: 38052295 DOI: 10.1016/j.ydbio.2023.11.010] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Revised: 11/10/2023] [Accepted: 11/29/2023] [Indexed: 12/07/2023]
Abstract
Xenopus laevis is a widely used model organism in developmental and regeneration studies. Despite several reports regarding targeted integration techniques in Xenopus, there is still room for improvement of them, especially in creating reporter lines that rely on endogenous regulatory enhancers/promoters. We developed a CRISPR-Cas9-based simple method to efficiently introduce a fluorescent protein gene into 5' untranslated regions (5'UTRs) of target genes in Xenopus laevis. A donor plasmid DNA encoding an enhanced green fluorescent protein (eGFP) flanked by a genomic fragment ranging from 66 bp to 878 bp including target 5'UTR was co-injected into fertilized eggs with a single guide RNA and Cas9 protein. Injections for krt12.2.L, myod1.S, sox2.L or brevican.S resulted in embryos expressing eGFP fluorescence in a tissue-specific manner, recapitulating endogenous expression of target genes. Integrations of the donor DNA into the target regions were examined by genotyping PCR for the eGFP-expressing embryos. The rate of embryos expressing the specific eGFP varied from 2.1% to 13.2% depending on the target locus and length of the genomic fragment in the donor plasmids. Germline transmission of an integrated DNA was observed. This simple method provides a powerful tool for exploring gene expression and function in developmental and regeneration research in X. laevis.
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Affiliation(s)
- Makoto Mochii
- Department of Life Science, Graduate School of Science, University of Hyogo, Akougun, Hyogo, 678-1297, Japan.
| | - Kai Akizuki
- Department of Life Science, Graduate School of Science, University of Hyogo, Akougun, Hyogo, 678-1297, Japan
| | - Hero Ossaka
- Department of Life Science, Graduate School of Science, University of Hyogo, Akougun, Hyogo, 678-1297, Japan
| | - Norie Kagawa
- Department of Life Science, Graduate School of Science, University of Hyogo, Akougun, Hyogo, 678-1297, Japan
| | - Yoshihiko Umesono
- Department of Life Science, Graduate School of Science, University of Hyogo, Akougun, Hyogo, 678-1297, Japan
| | - Ken-Ichi T Suzuki
- Emerging Model Organisms Facility, Trans-scale Biology Center, National Institute for Basic Biology, National Institutes of Natural Sciences, Okazaki, Aichi, 444-8585, Japan.
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Shibata Y, Okumura A, Mochii M, Suzuki KIT. Protocols for transgenesis at a safe harbor site in the Xenopus laevis genome using CRISPR-Cas9. STAR Protoc 2023; 4:102382. [PMID: 37389994 PMCID: PMC10511863 DOI: 10.1016/j.xpro.2023.102382] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Revised: 04/26/2023] [Accepted: 05/25/2023] [Indexed: 07/02/2023] Open
Abstract
We have established a new transgenesis protocol based on CRISPR-Cas9, "New and Easy XenopusTransgenesis (NEXTrans)," and identified a novel safe harbor site in African clawed frogs, Xenopus laevis. We describe steps in detail for the construction of NEXTrans plasmid and guide RNA, CRISPR-Cas9-mediated NEXTrans plasmid integration into the locus, and its validation by genomic PCR. This improved strategy allows us to simply generate transgenic animals that stably express the transgene. For complete details on the use and execution of this protocol, please refer to Shibata et al. (2022).1.
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Affiliation(s)
- Yuki Shibata
- Emerging Model Organisms Facility, Trans-scale Biology Center, National Institute for Basic Biology, National Institutes of Natural Sciences, Okazaki, Aichi 444-8585, Japan
| | - Akinori Okumura
- Emerging Model Organisms Facility, Trans-scale Biology Center, National Institute for Basic Biology, National Institutes of Natural Sciences, Okazaki, Aichi 444-8585, Japan
| | - Makoto Mochii
- Department of Life Science, Graduate School of Science, University of Hyogo, Akou-gun, Hyogo 678-1297, Japan.
| | - Ken-Ichi T Suzuki
- Emerging Model Organisms Facility, Trans-scale Biology Center, National Institute for Basic Biology, National Institutes of Natural Sciences, Okazaki, Aichi 444-8585, Japan.
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4
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Suzuki M, Iida M, Hayashi T, Suzuki KIT. CRISPR-Cas9-Based Functional Analysis in Amphibians: Xenopus laevis, Xenopus tropicalis, and Pleurodeles waltl. Methods Mol Biol 2023; 2637:341-357. [PMID: 36773159 DOI: 10.1007/978-1-0716-3016-7_26] [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] [Indexed: 02/12/2023]
Abstract
Amphibians have made many fundamental contributions to our knowledge, from basic biology to biomedical research on human diseases. Current genome editing tools based on the CRISPR-Cas system enable us to perform gene functional analysis in vivo, even in non-model organisms. We introduce here a highly efficient and easy protocol for gene knockout, which can be used in three different amphibians seamlessly: Xenopus laevis, Xenopus tropicalis, and Pleurodeles waltl. As it utilizes Cas9 ribonucleoprotein complex (RNP) for injection, this cloning-free method enables researchers to obtain founder embryos with a nearly complete knockout phenotype within a week. To evaluate somatic mutation rate and its correlation to the phenotype of a Cas9 RNP-injected embryo (crispant), we also present accurate and cost-effective genotyping methods using pooled amplicon-sequencing and a user-friendly web-based tool.
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Affiliation(s)
- Miyuki Suzuki
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Midori Iida
- Department of Bioscience and Bioinformatics, School of Computer Science and Systems Engineering, Kyushu Institute of Technology, Kitakyushu, Fukuoka, Japan
| | - Toshinori Hayashi
- Amphibian Research Center, Hiroshima University, Higashihiroshima, Hiroshima, Japan.,Graduate School of Integrated Sciences for Life, Hiroshima University, Higashihiroshima, Hiroshima, Japan
| | - Ken-Ichi T Suzuki
- Emerging Model Organisms Facility, Trans-scale Biology Center, National Institute for Basic Biology, Okazaki, Aichi, Japan.
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5
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Shibata Y, Suzuki M, Hirose N, Takayama A, Sanbo C, Inoue T, Umesono Y, Agata K, Ueno N, Suzuki KIT, Mochii M. CRISPR/Cas9-based simple transgenesis in Xenopus laevis. Dev Biol 2022; 489:76-83. [PMID: 35690103 DOI: 10.1016/j.ydbio.2022.06.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Revised: 06/03/2022] [Accepted: 06/06/2022] [Indexed: 11/25/2022]
Abstract
Transgenic techniques have greatly increased our understanding of the transcriptional regulation of target genes through live reporter imaging, as well as the spatiotemporal function of a gene using loss- and gain-of-function constructs. In Xenopus species, two well-established transgenic methods, restriction enzyme-mediated integration and I-SceI meganuclease-mediated transgenesis, have been used to generate transgenic animals. However, donor plasmids are randomly integrated into the Xenopus genome in both methods. Here, we established a new and simple targeted transgenesis technique based on CRISPR/Cas9 in Xenopus laevis. In this method, Cas9 ribonucleoprotein (RNP) targeting a putative harbor site (the transforming growth factor beta receptor 2-like (tgfbr2l) locus) and a preset donor plasmid DNA were co-injected into the one-cell stage embryos of X. laevis. Approximately 10% of faithful reporter expression was detected in F0 crispants in a promoter/enhancer-specific manner. Importantly, efficient germline transmission and stable transgene expression were observed in the F1 offspring. The simplicity of this method only required preparation of a donor vector containing the tgfbr2l genome fragment and Cas9 RNP targeting this site, which are common experimental procedures used in Xenopus laboratories. Our improved technique allows the simple generation of transgenic X. laevis, so is expected to become a powerful tool for reporter assay and gene function analysis.
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Affiliation(s)
- Yuki Shibata
- Center for the Development of New Model Organisms, National Institute for Basic Biology, National Institutes of Natural Sciences, Okazaki, Aichi, Japan
| | - Miyuki Suzuki
- Laboratory for Biothermology, National Institute for Basic Biology, National Institutes of Natural Sciences, Okazaki, Aichi, Japan
| | - Nao Hirose
- Department of Life Science, Graduate School of Science, University of Hyogo, Akou-gun, Hyogo, Japan
| | - Ayuko Takayama
- Center for the Development of New Model Organisms, National Institute for Basic Biology, National Institutes of Natural Sciences, Okazaki, Aichi, Japan
| | - Chiaki Sanbo
- Center for the Development of New Model Organisms, National Institute for Basic Biology, National Institutes of Natural Sciences, Okazaki, Aichi, Japan
| | - Takeshi Inoue
- Division of Adaptation Physiology, Faculty of Medicine, Tottori University, Yonago, Tottori, Japan
| | - Yoshihiko Umesono
- Department of Life Science, Graduate School of Science, University of Hyogo, Akou-gun, Hyogo, Japan
| | - Kiyokazu Agata
- Laboratory of Regeneration Biology, National Institute for Basic Biology, National Institutes of Natural Sciences, Okazaki, Aichi, Japan
| | - Naoto Ueno
- Division of Morphogenesis, Department of Developmental Biology, National Institute for Basic Biology, National Institutes of Natural Sciences, Okazaki, Aichi, Japan
| | - Ken-Ichi T Suzuki
- Center for the Development of New Model Organisms, National Institute for Basic Biology, National Institutes of Natural Sciences, Okazaki, Aichi, Japan.
| | - Makoto Mochii
- Department of Life Science, Graduate School of Science, University of Hyogo, Akou-gun, Hyogo, Japan.
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Sanoh S, Hanada H, Kashiwagi K, Mori T, Goto-Inoue N, Suzuki KIT, Mori J, Nakamura N, Yamamoto T, Kitamura S, Kotake Y, Sugihara K, Ohta S, Kashiwagi A. Amiodarone bioconcentration and suppression of metamorphosis in Xenopus. Aquat Toxicol 2020; 228:105623. [PMID: 32956954 DOI: 10.1016/j.aquatox.2020.105623] [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] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2020] [Revised: 08/27/2020] [Accepted: 09/01/2020] [Indexed: 06/11/2023]
Abstract
Trace concentrations of a number of pharmaceutically active compounds have been detected in the aquatic environment in many countries, where they are thought to have the potential to exert adverse effects on non-target organisms. Amiodarone (AMD) is one such high-risk compound commonly used in general hospitals. AMD is known to alter normal thyroid hormone (TH) function, although little information is available regarding the specific mechanism by which this disruption occurs. Anuran tadpole metamorphosis is a TH-controlled developmental process and has proven to be useful as a screening tool for environmental pollutants suspected of disrupting TH functions. In the present study, our objective was to clarify the effects of AMD on Xenopus metamorphosis as well as to assess the bioconcentration of this pharmaceutical in the liver. We found that AMD suppressed spontaneous metamorphosis, including tail regression and hindlimb elongation in pro-metamorphic stage tadpoles, which is controlled by endogenous circulating TH, indicating that AMD is a TH antagonist. In transgenic X. laevis tadpoles carrying plasmid DNA containing TH-responsive element (TRE) and a 5'-upstream promoter region of the TH receptor (TR) βA1 gene linked to a green fluorescent protein (EGFP) gene, triiodothyronine (T3) exposure induced a strong EGFP expression in the hind limbs, whereas the addition of AMD to T3 suppressed EGFP expression, suggesting that this drug interferes with the binding of T3 to TR, leading to the inhibition of TR-mediated gene expression. We also found AMD to be highly bioconcentrated in the liver of pro-metamorphic X. tropicalis tadpoles, and we monitored hepatic accumulation of this drug using mass spectrometry imaging (MSI). Our findings suggest that AMD imposes potential risk to aquatic wildlife by disrupting TH homeostasis, with further possibility of accumulating in organisms higher up in the food chain.
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Affiliation(s)
- Seigo Sanoh
- Graduate School of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima City, Hiroshima 734-8553, Japan.
| | - Hideki Hanada
- Amphibian Research Center, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526, Japan.
| | - Keiko Kashiwagi
- Amphibian Research Center, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526, Japan.
| | - Tsukasa Mori
- Department of Marine Science and Resources, Nihon University College of Bioresource Sciences, Kameino 1866, Fujisawa 252-0880, Japan.
| | - Naoko Goto-Inoue
- Department of Marine Science and Resources, Nihon University College of Bioresource Sciences, Kameino 1866, Fujisawa 252-0880, Japan.
| | - Ken-Ichi T Suzuki
- Graduate School of Integrated Sciences for Life, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526, Japan.
| | - Junpei Mori
- Graduate School of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima City, Hiroshima 734-8553, Japan.
| | - Naoki Nakamura
- Graduate School of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima City, Hiroshima 734-8553, Japan.
| | - Takashi Yamamoto
- Program of Mathematical and Life Sciences, Graduate School of Integrated Sciences for Life, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526, Japan.
| | - Shigeyuki Kitamura
- Nihon Pharmaceutical University, Komuro 10281, Ina-machi, Kitaadachi-gun, Saitama, 362-0806, Japan.
| | - Yaichiro Kotake
- Graduate School of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima City, Hiroshima 734-8553, Japan.
| | - Kazumi Sugihara
- Faculty of Pharmaceutical Sciences, Hiroshima International University, 5-1-1 Hirokoshinkai, Kure City, Hiroshima 737-0112, Japan.
| | - Shigeru Ohta
- Graduate School of Biomedical and Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima City, Hiroshima 734-8553, Japan; Wakayama Medical University, 811-1 Kimiidera, Wakayama City, Wakayama 641-8509, Japan.
| | - Akihiko Kashiwagi
- Amphibian Research Center, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526, Japan.
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Iida M, Suzuki M, Sakane Y, Nishide H, Uchiyama I, Yamamoto T, Suzuki KIT, Fujii S. A simple and practical workflow for genotyping of CRISPR-Cas9-based knockout phenotypes using multiplexed amplicon sequencing. Genes Cells 2020; 25:498-509. [PMID: 32323394 DOI: 10.1111/gtc.12775] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [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: 03/30/2020] [Revised: 04/15/2020] [Accepted: 04/15/2020] [Indexed: 11/28/2022]
Abstract
Founder animals carrying high proportions of somatic mutation induced by CRISPR-Cas9 enable a rapid and scalable strategy for the functional screening of numerous target genes in vivo. In this functional screening, genotyping using pooled amplicons with next-generation sequencing is the most suitable approach for large-scale management of multiple samples and accurate evaluation of the efficiency of Cas9-induced somatic mutations at target sites. Here, we present a simple workflow for genotyping of multiple CRISPR-Cas9-based knockout founders by pooled amplicon sequencing. Using custom barcoded primers, pooled amplicons from multiple individuals can be run in a single-indexed library on the Illumina MiSeq platform. Additionally, a user-friendly web tool, CLiCKAR, is available to simultaneously perform demultiplexing of pooled sequence data and evaluation of somatic mutation in each phenotype. CLiCKAR provides users with practical reports regarding the positions of insertions/deletions, as well as the frameshift ratio and tables containing mutation sequences, and read counts of each phenotype, with just a few clicks by the implementation of demultiplexing for pooled sample data and calculation of the frameshift ratio. This genotyping workflow can be harnessed to evaluate genotype-phenotype correlations in CRISPR-Cas9-based loss-of-function screening of numerous target genes in various organisms.
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Affiliation(s)
- Midori Iida
- Department of Bioscience and Bioinformatics, Kyushu Institute of Technology, Iizuka, Japan
| | - Miyuki Suzuki
- Graduate School of Integrated Sciences for Life, Hiroshima University, Higashi-Hiroshima, Japan
| | - Yuto Sakane
- Graduate School of Integrated Sciences for Life, Hiroshima University, Higashi-Hiroshima, Japan
| | - Hiroyo Nishide
- Laboratory of Genome Informatics (Data Integration and Analysis Facility), National Institute for Basic Biology, Okazaki, Japan
| | - Ikuo Uchiyama
- Laboratory of Genome Informatics (Data Integration and Analysis Facility), National Institute for Basic Biology, Okazaki, Japan
| | - Takashi Yamamoto
- Graduate School of Integrated Sciences for Life, Hiroshima University, Higashi-Hiroshima, Japan
| | - Ken-Ichi T Suzuki
- Graduate School of Integrated Sciences for Life, Hiroshima University, Higashi-Hiroshima, Japan.,Center for the Development of New Model Organisms, National Institute for Basic Biology, Okazaki, Japan
| | - Satoshi Fujii
- Department of Bioscience and Bioinformatics, Kyushu Institute of Technology, Iizuka, Japan
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Yoshinouchi Y, Shimizu S, Lee JS, Hirano M, Suzuki KIT, Kim EY, Iwata H. In vitro assessment of effects of persistent organic pollutants on the transactivation of estrogen receptor α and β (ERα and ERβ) from the Baikal seal (Pusa sibirica). Ecotoxicol Environ Saf 2019; 181:463-471. [PMID: 31228822 DOI: 10.1016/j.ecoenv.2019.06.033] [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] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Revised: 06/06/2019] [Accepted: 06/11/2019] [Indexed: 06/09/2023]
Abstract
To assess the effect of exposure to persistent organic pollutants (POPs) on the estrogen receptor (ER) signaling pathway in Baikal seals (Pusa sibirica), we investigated the molecular characterizations and functions of two Baikal seal ER (bsER) isoforms, bsERα and bsERβ. The bsERα and bsERβ cDNA clones isolated have an open reading frame of 595 and 530 amino acid residues, respectively. The tissue distribution analyses of bsER mRNAs showed that bsERα transcripts were primarily found in the ovary and uterus, and bsERβ in the muscle in wild Baikal seals. The immunofluorescence staining assay showed that 17β-estradiol (E2) treatment promoted the nuclear translocation of in vitro-expressed bsERα. Transient transfection of bsERα in U2OS cells enhanced the transcription of pS2, an ER target gene of E2. We then measured bsER-mediated transactivation potencies of POPs in an in vitro reporter gene assay system, in which a bsERα or bsERβ expression vector was transfected into COS-1 cells. For comparison, transactivation potencies of POPs on mouse ERs (mERα and mERβ) were also evaluated in the same manner. Results showed significant dose-dependent responses of bsERs and mERs when treated with p,p'-dichlorodiphenyltrichloroethane (p,p'-DDT), and p,p'-dichlorodiphenyldichloroethylene (p,p'-DDE). bsERs and mERs showed no response when exposed to polychlorinated biphenyls (PCBs) or 2,3,7,8-tetrachlorodibenzo-p-dioxin. Comparison of the dose-response curves of DDTs across species (bsERs vs. mERs) showed that bsERα had a response similar to mERα, but bsERβ was less sensitive than mERβ. Comparing the lowest observable effective concentrations of p,p'-DDT (2.8 μM) and p,p'-DDE (10 μM) for in vitro bsERα-mediated transactivation with their hepatic concentrations in wild Baikal seals indicated that some individuals accumulated these compounds at levels comparable to the effective concentrations, suggesting the potential disruption of the bsERα signaling pathway in the wild population by these compounds. Co-transfection experiments with bsER and the aryl hydrocarbon receptor (AHR) suggested that high accumulation of estrogenic compounds exerts a synergistic effect with dioxin-like congeners on ER signaling through AHR activation in the wild seal population.
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Affiliation(s)
- Yuka Yoshinouchi
- Center for Marine Environmental Studies (CMES), Ehime University, Bunkyo-cho 2-5, Matsuyama, 790-8577, Japan
| | - Sachiko Shimizu
- Center for Marine Environmental Studies (CMES), Ehime University, Bunkyo-cho 2-5, Matsuyama, 790-8577, Japan
| | - Jin-Seon Lee
- Center for Marine Environmental Studies (CMES), Ehime University, Bunkyo-cho 2-5, Matsuyama, 790-8577, Japan
| | - Masashi Hirano
- Center for Marine Environmental Studies (CMES), Ehime University, Bunkyo-cho 2-5, Matsuyama, 790-8577, Japan
| | - Ken-Ichi T Suzuki
- Department of Mathematical and Life Sciences, Graduate School of Science, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima, 739-8526, Japan
| | - Eun-Young Kim
- Department of Life and Nanopharmaceutical Science and Department of Biology, Kyung Hee University, Hoegi-Dong, Dongdaemun-Gu, Seoul, 130-701, Republic of Korea
| | - Hisato Iwata
- Center for Marine Environmental Studies (CMES), Ehime University, Bunkyo-cho 2-5, Matsuyama, 790-8577, Japan.
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Sakane Y, Iida M, Hasebe T, Fujii S, Buchholz DR, Ishizuya-Oka A, Yamamoto T, Suzuki KIT. Functional analysis of thyroid hormone receptor beta in Xenopus tropicalis founders using CRISPR-Cas. Biol Open 2018; 7:bio.030338. [PMID: 29358165 PMCID: PMC5829506 DOI: 10.1242/bio.030338] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [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] [Indexed: 01/06/2023] Open
Abstract
Amphibians provide an ideal model to study the actions of thyroid hormone (TH) in animal development because TH signaling via two TH receptors, TRα and TRβ, is indispensable for amphibian metamorphosis. However, specific roles for the TRβ isoform in metamorphosis are poorly understood. To address this issue, we generated trβ-disrupted Xenopus tropicalis tadpoles using the CRISPR-Cas system. We first established a highly efficient and rapid workflow for gene disruption in the founder generation (F0) by injecting sgRNA and Cas9 ribonucleoprotein. Most embryos showed severe mutant phenotypes carrying high somatic mutation rates. Utilizing this founder analysis system, we examined the role of trβ in metamorphosis. trβ-disrupted pre-metamorphic tadpoles exhibited mixed responsiveness to exogenous TH. Specifically, gill resorption and activation of several TH-response genes, including trβ itself and two protease genes, were impaired. However, hind limb outgrowth and induction of the TH-response genes, klf9 and fra-2, were not affected by loss of trβ Surprisingly, trβ-disrupted tadpoles were able to undergo spontaneous metamorphosis normally, except for a slight delay in tail resorption. These results indicate TRβ is not required but contributes to the timing of resorptive events of metamorphosis.
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Affiliation(s)
- Yuto Sakane
- Department of Mathematical and Life Sciences, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8526, Japan
| | - Midori Iida
- Department of Bioscience and Bioinformatics, Kyushu Institute of Technology, Iizuka, Fukuoka 820-8502, Japan
| | - Takashi Hasebe
- Department of Biology, Nippon Medical School, Musashino, Tokyo 180-0023, Japan
| | - Satoshi Fujii
- Department of Bioscience and Bioinformatics, Kyushu Institute of Technology, Iizuka, Fukuoka 820-8502, Japan
| | - Daniel R Buchholz
- Department of Biological Sciences, University of Cincinnati, 312 Clifton Ct., Cincinnati, OH, 45221, USA
| | - Atsuko Ishizuya-Oka
- Department of Biology, Nippon Medical School, Musashino, Tokyo 180-0023, Japan
| | - Takashi Yamamoto
- Department of Mathematical and Life Sciences, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8526, Japan
| | - Ken-Ichi T Suzuki
- Department of Mathematical and Life Sciences, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8526, Japan
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Satoh A, Mitogawa K, Saito N, Suzuki M, Suzuki KIT, Ochi H, Makanae A. Reactivation of larval keratin gene (krt62.L) in blastema epithelium during Xenopus froglet limb regeneration. Dev Biol 2017; 432:265-272. [PMID: 29079423 DOI: 10.1016/j.ydbio.2017.10.015] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [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: 06/12/2017] [Revised: 10/19/2017] [Accepted: 10/19/2017] [Indexed: 10/18/2022]
Abstract
Limb regeneration is considered a form of limb redevelopment because of the molecular and morphological similarities. Forming a regeneration blastema is, in essence, creating a developing limb bud in an adult body. This reactivation of a developmental process in a mature body is worth studying. Xenopus laevis has a biphasic life cycle that involves distinct larval and adult stages. These distinct developmental stages are useful for investigating the reactivation of developmental processes in post-metamorphic frogs (froglets). In this study, we focused on the re-expression of a larval gene (krt62.L) during Xenopus froglet limb regeneration. Recently renamed krt62.L, this gene was known as the larval keratin (xlk) gene, which is specific to larval-tadpole stages. During limb regeneration in a froglet, krt62.L was re-expressed in a basal layer of blastema epithelium, where adult-specific keratin (Krt12.6.S) expression was also observable. Nerves produce important regulatory factors for amphibian limb regeneration, and also play a role in blastema formation and maintenance. The effect of nerve function on krt62.L expression could be seen in the maintenance of krt62.L expression, but not in its induction. When an epidermis-stripped limb bud was grafted in a froglet blastema, the grafted limb bud could reach the digit-forming stage. This suggests that krt62.L-positive froglet blastema epithelium is able to support the limb development process. These findings imply that the developmental process is locally reactivated in an postmetamorphic body during limb regeneration.
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Affiliation(s)
- Akira Satoh
- Okayama University, Research Core for Interdisciplinary Sciences (RCIS), 3-1-1, Tushimanaka, Kita-ku, Okayama 700-6230, Japan.
| | - Kazumasa Mitogawa
- Okayama University, Research Core for Interdisciplinary Sciences (RCIS), 3-1-1, Tushimanaka, Kita-ku, Okayama 700-6230, Japan
| | - Nanami Saito
- Okayama University, Research Core for Interdisciplinary Sciences (RCIS), 3-1-1, Tushimanaka, Kita-ku, Okayama 700-6230, Japan
| | - Miyuki Suzuki
- Hiroshima University, Department of Mathematical and Life Sciences, Graduate School of Science, 1-3-1, Kagamiyama, Higashihiroshima, Hiroshima 739-8526, Japan
| | - Ken-Ichi T Suzuki
- Hiroshima University, Department of Mathematical and Life Sciences, Graduate School of Science, 1-3-1, Kagamiyama, Higashihiroshima, Hiroshima 739-8526, Japan
| | - Haruki Ochi
- Institute for Promotion of Medical Science Research, Yamagata University, Faculty of Medicine, 2-2-2 Iida-Nishi, Yamagata-shi, Yamagata 990-9585, Japan
| | - Aki Makanae
- Okayama University, Research Core for Interdisciplinary Sciences (RCIS), 3-1-1, Tushimanaka, Kita-ku, Okayama 700-6230, Japan
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11
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Matsushita M, Ochiai H, Suzuki KIT, Hayashi S, Yamamoto T, Awazu A, Sakamoto N. Dynamic changes in the interchromosomal interaction of early histone gene loci during development of sea urchin. J Cell Sci 2017; 130:4097-4107. [PMID: 29084822 DOI: 10.1242/jcs.206862] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [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: 06/01/2017] [Accepted: 10/22/2017] [Indexed: 12/21/2022] Open
Abstract
The nuclear positioning and chromatin dynamics of eukaryotic genes are closely related to the regulation of gene expression, but they have not been well examined during early development, which is accompanied by rapid cell cycle progression and dynamic changes in nuclear organization, such as nuclear size and chromatin constitution. In this study, we focused on the early development of the sea urchin Hemicentrotus pulcherrimus and performed three-dimensional fluorescence in situ hybridization of gene loci encoding early histones (one of the types of histone in sea urchin). There are two non-allelic early histone gene loci per sea urchin genome. We found that during the morula stage, when the early histone gene expression levels are at their maximum, interchromosomal interactions were often formed between the early histone gene loci on separate chromosomes and that the gene loci were directed to locate to more interior positions. Furthermore, these interactions were associated with the active transcription of the early histone genes. Thus, such dynamic interchromosomal interactions may contribute to the efficient synthesis of early histone mRNA during the morula stage of sea urchin development.
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Affiliation(s)
- Masaya Matsushita
- Department of Mathematical and Life Sciences, Graduate School of Science, Hiroshima University, Higashi-Hiroshima 739-8526, Japan
| | - Hiroshi Ochiai
- Department of Mathematical and Life Sciences, Graduate School of Science, Hiroshima University, Higashi-Hiroshima 739-8526, Japan.,JST, PRESTO, Higashi-Hiroshima 739-8530, Japan
| | - Ken-Ichi T Suzuki
- Department of Mathematical and Life Sciences, Graduate School of Science, Hiroshima University, Higashi-Hiroshima 739-8526, Japan
| | - Sayaka Hayashi
- Department of Mathematical and Life Sciences, Graduate School of Science, Hiroshima University, Higashi-Hiroshima 739-8526, Japan
| | - Takashi Yamamoto
- Department of Mathematical and Life Sciences, Graduate School of Science, Hiroshima University, Higashi-Hiroshima 739-8526, Japan.,Research Center for the Mathematics on Chromatin Live Dynamics, Hiroshima University, Higashi-Hiroshima 739-8526, Japan
| | - Akinori Awazu
- Department of Mathematical and Life Sciences, Graduate School of Science, Hiroshima University, Higashi-Hiroshima 739-8526, Japan.,Research Center for the Mathematics on Chromatin Live Dynamics, Hiroshima University, Higashi-Hiroshima 739-8526, Japan
| | - Naoaki Sakamoto
- Department of Mathematical and Life Sciences, Graduate School of Science, Hiroshima University, Higashi-Hiroshima 739-8526, Japan .,Research Center for the Mathematics on Chromatin Live Dynamics, Hiroshima University, Higashi-Hiroshima 739-8526, Japan
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12
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Mori J, Sanoh S, Kashiwagi K, Hanada H, Shigeta M, Suzuki KIT, Yamamoto T, Kotake Y, Sugihara K, Kitamura S, Kashiwagi A, Ohta S. Developmental changes in drug-metabolizing enzyme expression during metamorphosis of Xenopus tropicalis. J Toxicol Sci 2017; 42:605-613. [PMID: 28904296 DOI: 10.2131/jts.42.605] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [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: 11/02/2022]
Abstract
A large number of chemicals are routinely detected in aquatic environments, and these chemicals may adversely affect aquatic organisms. Accurate risk assessment requires understanding drug-metabolizing systems in aquatic organisms because metabolism of these chemicals is a critical determinant of chemical bioaccumulation and related toxicity. In this study, we evaluated mRNA expression levels of nuclear receptors and drug-metabolizing enzymes as well as cytochrome P450 (CYP) activities in pro-metamorphic tadpoles, froglets, and adult frogs to determine how drug-metabolizing systems are altered at different life stages. We found that drug-metabolizing systems in tadpoles were entirely immature, and therefore, tadpoles appeared to be more susceptible to chemicals compared with metamorphosed frogs. On the other hand, cyp1a mRNA expression and CYP1A-like activity were higher in tadpoles. We found that thyroid hormone (TH), which increases during metamorphosis, induced CYP1A-like activity. Because endogenous TH concentration is significantly increased during metamorphosis, endogenous TH would induce CYP1A-like activity in tadpoles.
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Affiliation(s)
- Junpei Mori
- Graduate School of Biomedical and Health Science, Hiroshima University
| | - Seigo Sanoh
- Graduate School of Biomedical and Health Science, Hiroshima University
| | | | | | | | | | | | - Yaichiro Kotake
- Graduate School of Biomedical and Health Science, Hiroshima University
| | - Kazumi Sugihara
- Faculty of Pharmaceutical Sciences, Hiroshima International University
| | | | | | - Shigeru Ohta
- Graduate School of Biomedical and Health Science, Hiroshima University
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13
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Suzuki KIT, Suzuki M, Shigeta M, Fortriede JD, Takahashi S, Mawaribuchi S, Yamamoto T, Taira M, Fukui A. Clustered Xenopus keratin genes: A genomic, transcriptomic, and proteomic analysis. Dev Biol 2016; 426:384-392. [PMID: 27842699 DOI: 10.1016/j.ydbio.2016.10.018] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2016] [Revised: 10/21/2016] [Accepted: 10/26/2016] [Indexed: 01/21/2023]
Abstract
Keratin genes belong to the intermediate filament superfamily and their expression is altered following morphological and physiological changes in vertebrate epithelial cells. Keratin genes are divided into two groups, type I and II, and are clustered on vertebrate genomes, including those of Xenopus species. Various keratin genes have been identified and characterized by their unique expression patterns throughout ontogeny in Xenopus laevis; however, compilation of previously reported and newly identified keratin genes in two Xenopus species is required for our further understanding of keratin gene evolution, not only in amphibians but also in all terrestrial vertebrates. In this study, 120 putative type I and II keratin genes in total were identified based on the genome data from two Xenopus species. We revealed that most of these genes are highly clustered on two homeologous chromosomes, XLA9_10 and XLA2 in X. laevis, and XTR10 and XTR2 in X. tropicalis, which are orthologous to those of human, showing conserved synteny among tetrapods. RNA-Seq data from various embryonic stages and adult tissues highlighted the unique expression profiles of orthologous and homeologous keratin genes in developmental stage- and tissue-specific manners. Moreover, we identified dozens of epidermal keratin proteins from the whole embryo, larval skin, tail, and adult skin using shotgun proteomics. In light of our results, we discuss the radiation, diversification, and unique expression of the clustered keratin genes, which are closely related to epidermal development and terrestrial adaptation during amphibian evolution, including Xenopus speciation.
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Affiliation(s)
- Ken-Ichi T Suzuki
- Graduate School of Science, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526, Japan.
| | - Miyuki Suzuki
- Graduate School of Science, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526, Japan
| | - Mitsuki Shigeta
- Graduate School of Science, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526, Japan
| | - Joshua D Fortriede
- Xenbase, Division of Developmental Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA
| | - Shuji Takahashi
- Graduate School of Science, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526, Japan
| | - Shuuji Mawaribuchi
- Kitasato Institute for Life Sciences, Kitasato University, 5-9-1 Shirokane, Minato-ku, Tokyo 108-8641, Japan
| | - Takashi Yamamoto
- Graduate School of Science, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526, Japan
| | - Masanori Taira
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Akimasa Fukui
- Laboratory of Tissue and Polymer Sciences, Faculty of Advanced Life Science, Hokkaido University, N10W8, Sapporo 060-0810, Japan.
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14
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Choi J, Suzuki KIT, Sakuma T, Shewade L, Yamamoto T, Buchholz DR. Unliganded thyroid hormone receptor α regulates developmental timing via gene repression in Xenopus tropicalis. Endocrinology 2015; 156:735-44. [PMID: 25456067 PMCID: PMC4298327 DOI: 10.1210/en.2014-1554] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Thyroid hormone (TH) receptor (TR) expression begins early in development in all vertebrates when circulating TH levels are absent or minimal, yet few developmental roles for unliganded TRs have been established. Unliganded TRs are expected to repress TH-response genes, increase tissue responsivity to TH, and regulate the timing of developmental events. Here we examined the role of unliganded TRα in gene repression and development in Xenopus tropicalis. We used transcription activator-like effector nuclease gene disruption technology to generate founder animals with mutations in the TRα gene and bred them to produce F1 offspring with a normal phenotype and a mutant phenotype, characterized by precocious hind limb development. Offspring with a normal phenotype had zero or one disrupted TRα alleles, and tadpoles with the mutant hind limb phenotype had two truncated TRα alleles with frame shift mutations between the two zinc fingers followed by 40-50 mutant amino acids and then an out-of-frame stop codon. We examined TH-response gene expression and early larval development with and without exogenous TH in F1 offspring. As hypothesized, mutant phenotype tadpoles had increased expression of TH-response genes in the absence of TH and impaired induction of these same genes after exogenous TH treatment, compared with normal phenotype animals. Also, mutant hind limb phenotype animals had reduced hind limb and gill responsivity to exogenous TH. Similar results in methimazole-treated tadpoles showed that increased TH-response gene expression and precocious development were not due to early production of TH. These results indicate that unliganded TRα delays developmental progression by repressing TH-response genes.
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Affiliation(s)
- Jinyoung Choi
- Department of Biological Sciences (J.C., L.S., D.R.B.), University of Cincinnati, Cincinnati, Ohio 45221; and Department of Mathematical and Life Sciences (K.T.S., T.S., T.Y.), Graduate School of Science, Hiroshima University, Hiroshima 739-8526, Japan
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15
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Sakane Y, Sakuma T, Kashiwagi K, Kashiwagi A, Yamamoto T, Suzuki KIT. Targeted mutagenesis of multiple and paralogous genes in Xenopus laevis using two pairs of transcription activator-like effector nucleases. Dev Growth Differ 2013; 56:108-14. [PMID: 24329851 DOI: 10.1111/dgd.12105] [Citation(s) in RCA: 30] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2013] [Revised: 10/20/2013] [Accepted: 10/20/2013] [Indexed: 11/28/2022]
Abstract
Transcription activator-like effector nucleases (TALENs) have been extensively used in genome editing in various organisms. In some cases, however, it is difficult to efficiently disrupt both paralogous genes using a single pair of TALENs in Xenopus laevis because of its polyploidy. Here, we report targeted mutagenesis of multiple and paralogous genes using two pairs of TALENs in X. laevis. First, we show simultaneous targeted mutagenesis of three genes, tyrosinase paralogues (tyra and tyrb) and enhanced green fluorescent protein (egfp) by injection of two TALENs pairs in transgenic embryos carrying egfp. Consistent with the high frequency of both severe phenotypic traits, albinism and loss of GFP fluorescence, frameshift mutation rates of tyr paralogues and egfp reached 40-80%. Next, we show early introduction of TALEN-mediated mutagenesis of these target loci during embryogenesis. Finally, we also demonstrate that two different pairs of TALENs can simultaneously introduce mutations to both paralogues encoding histone chaperone with high efficiency. Our results suggest that targeted mutagenesis of multiple genes using TALENs can be applied to analyze the functions of paralogous genes with redundancy in X. laevis.
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Affiliation(s)
- Yuto Sakane
- Department of Mathematical and Life Sciences, Graduate School of Science, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima, 739-8526, Japan
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16
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Suzuki KIT, Isoyama Y, Kashiwagi K, Sakuma T, Ochiai H, Sakamoto N, Furuno N, Kashiwagi A, Yamamoto T. High efficiency TALENs enable F0 functional analysis by targeted gene disruption in Xenopus laevis embryos. Biol Open 2013; 2:448-52. [PMID: 23789092 PMCID: PMC3654262 DOI: 10.1242/bio.20133855] [Citation(s) in RCA: 71] [Impact Index Per Article: 6.5] [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: 12/14/2012] [Accepted: 02/11/2013] [Indexed: 11/20/2022] Open
Abstract
Recently, gene editing with transcription activator-like effector nucleases (TALENs) has been used in the life sciences. TALENs can be easily customized to recognize a specific DNA sequence and efficiently introduce double-strand breaks at the targeted genomic locus. Subsequent non-homologous end-joining repair leads to targeted gene disruption by base insertion, deletion, or both. Here, to readily evaluate the efficacy of TALENs in Xenopus laevis embryos, we performed the targeted gene disruption of tyrosinase (tyr) and pax6 genes that are involved in pigmentation and eye formation, respectively. We constructed TALENs targeting tyr and pax6 and injected their mRNAs into fertilized eggs at the one-cell stage. Expectedly, introduction of tyr TALEN mRNA resulted in drastic loss of pigmentation with high efficiency. Similarly, for pax6, TALENs led to deformed eyes in the injected embryos. We confirmed mutations of the target alleles by restriction enzyme digestion and sequence analyses of genomic PCR products. Surprisingly, not only biallelic but also paralogous, gene disruption was observed. Our results demonstrate that targeted gene disruption by TALENs provides a method comparable to antisense morpholinos in analyzing gene function in Xenopus F0 embryos, but also applies beyond embryogenesis to any life stage.
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Affiliation(s)
- Ken-Ichi T Suzuki
- Department of Mathematical and Life Sciences, Graduate School of Science, Hiroshima University , 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526 , Japan
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Motoi N, Hasebe T, Suzuki KIT, Ishizuya-Oka A. Spatiotemporal expression profile of no29/nucleophosmin3 in the intestine of Xenopus laevis during metamorphosis. Cell Tissue Res 2011; 344:445-53. [PMID: 21519897 DOI: 10.1007/s00441-011-1163-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2011] [Accepted: 03/04/2011] [Indexed: 01/30/2023]
Abstract
A Xenopus laevis homolog of nucleophosmin/nucleoplasmin3 (NPM3), no29, has been previously identified as a thyroid hormone (TH)-response gene during TH-induced metamorphosis. X. laevis has another NPM3 homolog (npm3) in the pseudo-tetraploid genome, whereas X. tropicalis possesses one ortholog in the diploid genome. To assess the possible roles of these NPM3 homologs in amphibian metamorphosis, we have analyzed their expression profiles in X. laevis tadpoles. Levels of no29 and npm3 mRNA are rapidly up-regulated by exogenous TH in various organs of the premetamorphic tadpoles. Notably, in the small intestine, no29 and npm3 mRNA levels are transiently up-regulated during metamorphic climax, when progenitor/stem cells of the adult epithelium appear and actively proliferate. In situ hybridization analysis has revealed that the no29 transcript is specifically localized in adult epithelial progenitor/stem cells of the intestine during natural and TH-induced metamorphosis. Double-staining for in situ hybridization and immunohistochemistry has shown co-expression of no29 mRNA and no38 protein (an ortholog of NPM1), which is known to interact with NPM3 and to regulate cell proliferation in mammals. Thus, no29/npm3 might serve as a stem cell marker in the intestine during metamorphosis.
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Affiliation(s)
- Natsuki Motoi
- Graduate School of Science, Hiroshima University, 1-3-1 Kagamiyama, Higashihiroshima, Hiroshima, 939-8526, Japan
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