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Styrkarsdottir U, Stefansdottir L, Thorleifsson G, Stefansson OA, Saevarsdottir S, Lund SH, Rafnar T, Hoshijima K, Novak K, Oreiro N, Rego-Perez I, Hansen C, Kazmers N, Kiemeney LA, Blanco FJ, Barker T, Kloppenburg M, Jurynec MJ, Gudbjartsson DF, Jonsson H, Thorsteinsdottir U, Stefansson K. Meta-analysis of erosive hand osteoarthritis identifies four common variants that associate with relatively large effect. Ann Rheum Dis 2023; 82:873-880. [PMID: 36931692 DOI: 10.1136/ard-2022-223468] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Accepted: 02/25/2023] [Indexed: 03/19/2023]
Abstract
OBJECTIVES Erosive hand osteoarthritis (EHOA) is a severe subset of hand osteoarthritis (OA). It is unclear if EHOA is genetically different from other forms of OA. Sequence variants at ten loci have been associated with hand OA but none with EHOA. METHODS We performed meta-analysis of EHOA in 1484 cases and 550 680 controls, from 5 populations. To identify causal genes, we performed eQTL and plasma pQTL analyses, and developed one zebrafish mutant. We analysed associations of variants with other traits and estimated shared genetics between EHOA and other traits. RESULTS Four common sequence variants associated with EHOA, all with relatively high effect. Rs17013495 (SPP1/MEPE, OR=1.40, p=8.4×10-14) and rs11243284 (6p24.3, OR=1.35, p=4.2×10-11) have not been associated with OA, whereas rs11631127 (ALDH1A2, OR=1.46, p=7.1×10-18), and rs1800801 (MGP, OR=1.37, p=3.6×10-13) have previously been associated with hand OA. The association of rs1800801 (MGP) was consistent with a recessive mode of inheritance in contrast to its additive association with hand OA (OR homozygotes vs non-carriers=2.01, 95% CI 1.71 to 2.37). All four variants associated nominally with finger OA, although with substantially lower effect. We found shared genetic components between EHOA and other OA measures, grip strength, urate levels and gout, but not rheumatoid arthritis. We identified ALDH1A2, MGP and BMP6 as causal genes for EHOA, with loss-of-function Bmp6 zebrafish mutants displaying EHOA-like phenotypes. CONCLUSIONS We report on significant genetic associations with EHOA. The results support the view of EHOA as a form of severe hand OA and partly separate it from OA in larger joints.
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Affiliation(s)
| | | | | | | | - Saedis Saevarsdottir
- Population Genomics, deCODE genetics / Amgen Inc, Reykjavik, Iceland.,Faculty of Medicine, School of Health Sciences, University of Iceland, Reykjavik, Iceland
| | - Sigrun H Lund
- Statistics, deCODE genetics / Amgen Inc, Reykjavik, Iceland
| | - Thorunn Rafnar
- Population Genomics, deCODE genetics / Amgen Inc, Reykjavik, Iceland
| | - Kazuyuki Hoshijima
- Department of Human Genetics, University of Utah, Salt Lake City, Utah, USA
| | - Kendra Novak
- Department of Orthopaedics, University of Utah, Salt Lake City, Utah, USA
| | - Natividad Oreiro
- Rheumatology Division, A Coruna University Hospital, A Coruna, Spain
| | | | - Channing Hansen
- Enterprise Analytics, Intermountain Healthcare, Salt Lake City, Utah, USA
| | - Nikolas Kazmers
- Department of Orthopaedics, University of Utah, Salt Lake City, Utah, USA
| | - Lambertus A Kiemeney
- Radboud University Medical Center, Radboud Institute for Health Science, Radboud University, Nijmegen, The Netherlands
| | - Francisco J Blanco
- Rheumatology Division, A Coruna University Hospital, A Coruna, Spain.,Department of Phisiotherapy, Medicine and Biomedical Sciences, A Coruna University Hospital, A Coruna, Spain
| | - Tyler Barker
- Department of Orthopaedics, University of Utah, Salt Lake City, Utah, USA.,Precision Genomics, Intermountain Healthcare, Salt Lake City, Utah, USA.,Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah, USA
| | - Margreet Kloppenburg
- Department of Rheumatology, Department of Clinical Epidemiology, Leiden University Medical Center, Leiden, The Netherlands
| | - Michael J Jurynec
- Department of Human Genetics, University of Utah, Salt Lake City, Utah, USA
| | - Daniel F Gudbjartsson
- Statistics, deCODE genetics / Amgen Inc, Reykjavik, Iceland.,School of Engineering and Natural Sciences, University of Iceland, Reykjavik, Iceland
| | - Helgi Jonsson
- Faculty of Medicine, School of Health Sciences, University of Iceland, Reykjavik, Iceland.,Department of Medicine, Landspitali University Hospital, Reykjavik, Iceland
| | - Unnur Thorsteinsdottir
- Population Genomics, deCODE genetics / Amgen Inc, Reykjavik, Iceland.,Faculty of Medicine, School of Health Sciences, University of Iceland, Reykjavik, Iceland
| | - Kari Stefansson
- Faculty of Medicine, School of Health Sciences, University of Iceland, Reykjavik, Iceland .,deCODE genetics / Amgen Inc, Reykjavik, Capital, Iceland
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2
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Jurynec MJ, Gavile CM, Honeggar M, Ma Y, Veerabhadraiah SR, Novak KA, Hoshijima K, Kazmers NH, Grunwald DJ. NOD/RIPK2 signalling pathway contributes to osteoarthritis susceptibility. Ann Rheum Dis 2022; 81:1465-1473. [PMID: 35732460 PMCID: PMC9474725 DOI: 10.1136/annrheumdis-2022-222497] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [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: 03/16/2022] [Accepted: 06/07/2022] [Indexed: 12/21/2022]
Abstract
OBJECTIVES How inflammatory signalling contributes to osteoarthritis (OA) susceptibility is undetermined. An allele encoding a hyperactive form of the Receptor Interacting Protein Kinase 2 (RIPK2) proinflammatory signalling intermediate has been associated with familial OA. To test whether altered nucleotide-binding oligomerisation domain (NOD)/RIPK2 pathway activity causes heightened OA susceptibility, we investigated whether variants affecting additional pathway components are associated with familial OA. To determine whether the Ripk2104Asp disease allele is sufficient to account for the familial phenotype, we determined the effect of the allele on mice. METHODS Genomic analysis of 150 independent families with dominant inheritance of OA affecting diverse joints was used to identify coding variants that segregated strictly with occurrence of OA. Genome editing was used to introduce the OA-associated RIPK2 (p.Asn104Asp) allele into the genome of inbred mice. The consequences of the Ripk2104Asp disease allele on physiology and OA susceptibility in mice were measured by histology, immunohistochemistry, serum cytokine levels and gene expression. RESULTS We identified six novel variants affecting components of the NOD/RIPK2 inflammatory signalling pathway that are associated with familial OA affecting the hand, shoulder or foot. The Ripk2104Asp allele acts dominantly to alter basal physiology and response to trauma in the mouse knee. Whereas the knees of uninjured Ripk2Asp104 mice appear normal histologically, the joints exhibit a set of marked gene expression changes reminiscent of overt OA. Although the Ripk2104Asp mice lack evidence of chronically elevated systemic inflammation, they do exhibit significantly increased susceptibility to post-traumatic OA (PTOA). CONCLUSIONS Two types of data support the hypothesis that altered NOD/RIPK2 signalling confers susceptibility to OA.
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Affiliation(s)
- Michael J Jurynec
- Department of Orthopaedics, University of Utah Health, Salt Lake City, Utah, USA
- Department of Human Genetics, University of Utah Health, Salt Lake City, Utah, USA
| | - Catherine M Gavile
- Department of Orthopaedics, University of Utah Health, Salt Lake City, Utah, USA
| | - Matthew Honeggar
- Department of Orthopaedics, University of Utah Health, Salt Lake City, Utah, USA
| | - Ying Ma
- Department of Orthopaedics, University of Utah Health, Salt Lake City, Utah, USA
| | | | - Kendra A Novak
- Department of Orthopaedics, University of Utah Health, Salt Lake City, Utah, USA
| | - Kazuyuki Hoshijima
- Department of Human Genetics, University of Utah Health, Salt Lake City, Utah, USA
| | - Nikolas H Kazmers
- Department of Orthopaedics, University of Utah Health, Salt Lake City, Utah, USA
| | - David J Grunwald
- Department of Human Genetics, University of Utah Health, Salt Lake City, Utah, USA
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3
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Casey MA, Hill JT, Hoshijima K, Bryan CD, Gribble SL, Brown JT, Chien CB, Yost HJ, Kwan KM. Shutdown corner, a large deletion mutant isolated from a haploid mutagenesis screen in zebrafish. G3 (Bethesda) 2022; 12:jkab442. [PMID: 35079792 PMCID: PMC9210284 DOI: 10.1093/g3journal/jkab442] [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] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Accepted: 12/15/2021] [Indexed: 11/13/2022]
Abstract
Morphogenesis, the formation of three-dimensional organ structures, requires precise coupling of genetic regulation and complex cell behaviors. The genetic networks governing many morphogenetic systems, including that of the embryonic eye, are poorly understood. In zebrafish, several forward genetic screens have sought to identify factors regulating eye development. These screens often look for eye defects at stages after the optic cup is formed and when retinal neurogenesis is under way. This approach can make it difficult to identify mutants specific for morphogenesis, as opposed to neurogenesis. To this end, we carried out a forward genetic, small-scale haploid mutagenesis screen in zebrafish (Danio rerio) to identify factors that govern optic cup morphogenesis. We screened ∼100 genomes and isolated shutdown corner (sco), a mutant that exhibits multiple tissue defects and harbors a ∼10-Mb deletion that encompasses 89 annotated genes. Using a combination of live imaging and antibody staining, we found cell proliferation, cell death, and tissue patterning defects in the sco optic cup. We also observed other phenotypes, including paralysis, neuromuscular defects, and ocular vasculature defects. To date, the largest deletion mutants reported in zebrafish are engineered using CRISPR-Cas9 and are less than 300 kb. Because of the number of genes within the deletion interval, shutdown corner [Df(Chr05:sco)z207] could be a useful resource to the zebrafish community, as it may be helpful for gene mapping, understanding genetic interactions, or studying many genes lost in the mutant.
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Affiliation(s)
- Macaulie A Casey
- Department of Human Genetics, University of Utah, Salt Lake City, UT 84112, USA
| | - Jonathon T Hill
- Department of Cell Biology and Physiology, Brigham Young University, Provo, UT 84602, USA
| | - Kazuyuki Hoshijima
- Department of Human Genetics, University of Utah, Salt Lake City, UT 84112, USA
| | - Chase D Bryan
- Department of Molecular Genetics and Microbiology, University of Florida, Gainesville, FL 32611, USA
| | - Suzanna L Gribble
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, USA
| | - J Thomas Brown
- Department of Biomedical Informatics, Vanderbilt University, Nashville, TN 37203, USA
| | - Chi-Bin Chien
- Department of Neurobiology and Anatomy, University of Utah, Salt Lake City, UT 84112, USA
| | - H Joseph Yost
- Department of Neurobiology and Anatomy, University of Utah, Salt Lake City, UT 84112, USA
| | - Kristen M Kwan
- Department of Human Genetics, University of Utah, Salt Lake City, UT 84112, USA
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4
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Jurynec MJ, Bai X, Bisgrove BW, Jackson H, Nechiporuk A, Palu RAS, Grunwald HA, Su YC, Hoshijima K, Yost HJ, Zon LI, Grunwald DJ. The Paf1 complex and P-TEFb have reciprocal and antagonist roles in maintaining multipotent neural crest progenitors. Development 2019; 146:dev.180133. [PMID: 31784460 DOI: 10.1242/dev.180133] [Citation(s) in RCA: 9] [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: 05/08/2019] [Accepted: 11/21/2019] [Indexed: 01/01/2023]
Abstract
Multipotent progenitor populations are necessary for generating diverse tissue types during embryogenesis. We show the RNA polymerase-associated factor 1 complex (Paf1C) is required to maintain multipotent progenitors of the neural crest (NC) lineage in zebrafish. Mutations affecting each Paf1C component result in near-identical NC phenotypes; alyron mutant embryos carrying a null mutation in paf1 were analyzed in detail. In the absence of zygotic paf1 function, definitive premigratory NC progenitors arise but fail to maintain expression of the sox10 specification gene. The mutant NC progenitors migrate aberrantly and fail to differentiate appropriately. Blood and germ cell progenitor development is affected similarly. Development of mutant NC could be rescued by additional loss of positive transcription elongation factor b (P-TEFb) activity, a key factor in promoting transcription elongation. Consistent with the interpretation that inhibiting/delaying expression of some genes is essential for maintaining progenitors, mutant embryos lacking the CDK9 kinase component of P-TEFb exhibit a surfeit of NC progenitors and their derivatives. We propose Paf1C and P-TEFb act antagonistically to regulate the timing of the expression of genes needed for NC development.
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Affiliation(s)
- Michael J Jurynec
- Department of Human Genetics, University of Utah, Salt Lake City, UT 84112, USA
| | - Xiaoying Bai
- Stem Cell Program and Division of Hematology/Oncology, Children's Hospital and Dana Farber Cancer Institute, Howard Hughes Medical Institute, Harvard Medical School, Boston, MA 02115, USA
| | - Brent W Bisgrove
- Department of Neurobiology and Anatomy, University of Utah, Salt Lake City, UT 84132, USA
| | - Haley Jackson
- Department of Human Genetics, University of Utah, Salt Lake City, UT 84112, USA
| | - Alex Nechiporuk
- Department of Cell and Developmental Biology, School of Medicine, Oregon Health & Science University, Portland, OR 97239, USA
| | - Rebecca A S Palu
- Department of Human Genetics, University of Utah, Salt Lake City, UT 84112, USA
| | - Hannah A Grunwald
- Department of Human Genetics, University of Utah, Salt Lake City, UT 84112, USA
| | - Yi-Chu Su
- Department of Neurobiology and Anatomy, University of Utah, Salt Lake City, UT 84132, USA
| | - Kazuyuki Hoshijima
- Department of Human Genetics, University of Utah, Salt Lake City, UT 84112, USA
| | - H Joseph Yost
- Department of Neurobiology and Anatomy, University of Utah, Salt Lake City, UT 84132, USA
| | - Leonard I Zon
- Stem Cell Program and Division of Hematology/Oncology, Children's Hospital and Dana Farber Cancer Institute, Howard Hughes Medical Institute, Harvard Medical School, Boston, MA 02115, USA
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Hoshijima K, Jurynec MJ, Klatt Shaw D, Jacobi AM, Behlke MA, Grunwald DJ. Highly Efficient CRISPR-Cas9-Based Methods for Generating Deletion Mutations and F0 Embryos that Lack Gene Function in Zebrafish. Dev Cell 2019; 51:645-657.e4. [PMID: 31708433 DOI: 10.1016/j.devcel.2019.10.004] [Citation(s) in RCA: 125] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Revised: 09/13/2019] [Accepted: 10/03/2019] [Indexed: 11/24/2022]
Abstract
Inconsistent activity limits the use of CRISPR-Cas9 in zebrafish. We show supernumerary guanine nucleotides at the 5' ends of single guide RNAs (sgRNAs) account for diminished CRISPR-Cas9 activity in zebrafish embryos. Genomic sequences can be targeted consistently with extremely high efficiency using Cas9 ribonucleoproteins (RNPs) containing either a sgRNA molecule or a synthetic crRNA:tracrRNA duplex that perfectly matches the protospacer target site. Following injection of zebrafish eggs with such RNPs, virtually every copy of a targeted locus harbors an induced indel mutation. Loss of gene function is often complete, as F0 embryos closely resemble true null mutants without detectable non-specific effects. Mosaicism is sufficiently low in F0 embryos that cell non-autonomous gene functions can be probed effectively and redundant activities of genes can be uncovered when two genes are targeted simultaneously. Finally, heritable deletion mutations of at least 50 kbp can be readily induced using pairs of duplex guide RNPs targeted to a single chromosome.
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Affiliation(s)
- Kazuyuki Hoshijima
- Department of Human Genetics, University of Utah, Salt Lake City, UT 84112, USA
| | - Michael J Jurynec
- Department of Human Genetics, University of Utah, Salt Lake City, UT 84112, USA; Department of Orthopaedics, University of Utah, Salt Lake City, UT 84112, USA
| | - Dana Klatt Shaw
- Department of Human Genetics, University of Utah, Salt Lake City, UT 84112, USA
| | - Ashley M Jacobi
- Integrated DNA Technologies, 1710 Commercial Park, Coralville, IA 52241, USA
| | - Mark A Behlke
- Integrated DNA Technologies, 1710 Commercial Park, Coralville, IA 52241, USA
| | - David Jonah Grunwald
- Department of Human Genetics, University of Utah, Salt Lake City, UT 84112, USA.
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6
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Chagovetz AA, Klatt Shaw D, Ritchie E, Hoshijima K, Grunwald DJ. Interactions among ryanodine receptor isotypes contribute to muscle fiber type development and function. Dis Model Mech 2019; 13:dmm.038844. [PMID: 31383689 PMCID: PMC6906632 DOI: 10.1242/dmm.038844] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2019] [Accepted: 07/17/2019] [Indexed: 12/14/2022] Open
Abstract
Mutations affecting ryanodine receptor (RyR) calcium release channels commonly underlie congenital myopathies. Although these channels are known principally for their essential roles in muscle contractility, mutations in the human RYR1 gene result in a broad spectrum of phenotypes, including muscle weakness, altered proportions of fiber types, anomalous muscle fibers with cores or centrally placed nuclei, and dysmorphic craniofacial features. Currently, it is unknown which phenotypes directly reflect requirements for RyRs and which result secondarily to aberrant muscle function. To identify biological processes requiring RyR function, skeletal muscle development was analyzed in zebrafish embryos harboring protein-null mutations. RyR channels contribute to both muscle fiber development and function. Loss of some RyRs had modest effects, altering muscle fiber-type specification in the embryo without compromising viability. In addition, each RyR-encoding gene contributed to normal swimming behavior and muscle function. The RyR channels do not function in a simple additive manner. For example, although isoform RyR1a is sufficient for muscle contraction in the absence of RyR1b, RyR1a normally attenuates the activity of the co-expressed RyR1b channel in slow muscle. RyR3 also acts to modify the functions of other RyR channels. Furthermore, diminished RyR-dependent contractility affects both muscle fiber maturation and craniofacial development. These findings help to explain some of the heterogeneity of phenotypes that accompany RyR1 mutations in humans.
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Affiliation(s)
- Alexis A Chagovetz
- Department of Human Genetics, University of Utah, Salt Lake City, UT 84112, USA
| | - Dana Klatt Shaw
- Department of Human Genetics, University of Utah, Salt Lake City, UT 84112, USA
| | - Erin Ritchie
- Department of Human Genetics, University of Utah, Salt Lake City, UT 84112, USA
| | - Kazuyuki Hoshijima
- Department of Human Genetics, University of Utah, Salt Lake City, UT 84112, USA
| | - David J Grunwald
- Department of Human Genetics, University of Utah, Salt Lake City, UT 84112, USA
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7
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Morrow ZT, Maxwell AM, Hoshijima K, Talbot JC, Grunwald DJ, Amacher SL. tbx6l and tbx16 are redundantly required for posterior paraxial mesoderm formation during zebrafish embryogenesis. Dev Dyn 2017; 246:759-769. [PMID: 28691257 DOI: 10.1002/dvdy.24547] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [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: 11/22/2016] [Revised: 05/19/2017] [Accepted: 07/04/2017] [Indexed: 11/08/2022] Open
Abstract
BACKGROUND T-box genes encode a large transcription factor family implicated in many aspects of development. We are focusing on two related zebrafish T-box genes, tbx6l and tbx16, that are expressed in highly overlapping patterns in embryonic paraxial mesoderm. tbx16 mutants are deficient in trunk, but not tail, somites; we explored whether presence of tail somites in tbx16 mutants was due to compensatory function provided by the tbx6l gene. RESULTS We generated two zebrafish tbx6l mutant alleles. Loss of tbx6l has no apparent effect on embryonic development, nor does tbx6l loss enhance the phenotype of two other T-box gene mutants, ta and tbx6, or of the mesp family gene mutant msgn1. In contrast, loss of tbx6l function dramatically enhances the paraxial mesoderm deficiency of tbx16 mutants. CONCLUSIONS These data demonstrate that tbx6l and tbx16 genes function redundantly to direct tail somite development. tbx6l single mutants develop normally because tbx16 fully compensates for loss of tbx6l function. However, tbx6l only partially compensates for loss of tbx16 function. These results resolve the question of why loss of function of tbx16 gene, which is expressed throughout the ventral and paraxial mesoderm, profoundly affects somite development in the trunk but not the tail. Developmental Dynamics 246:759-769, 2017. © 2017 Wiley Periodicals, Inc.
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Affiliation(s)
- Zachary T Morrow
- Department of Molecular Genetics, The Ohio State University, Columbus, Ohio
| | - Adrienne M Maxwell
- Department of Molecular Genetics, The Ohio State University, Columbus, Ohio
| | - Kazuyuki Hoshijima
- Department of Human Genetics, University of Utah School of Medicine, Salt Lake City, Utah
| | - Jared C Talbot
- Department of Molecular Genetics, The Ohio State University, Columbus, Ohio.,Department of Biological Chemistry and Pharmacology, The Ohio State University School of Medicine, Columbus, Ohio.,Center for Muscle Health and Neuromuscular Disorders, The Ohio State University and Nationwide Children's Hospital, Columbus, Ohio
| | - David J Grunwald
- Department of Human Genetics, University of Utah School of Medicine, Salt Lake City, Utah
| | - Sharon L Amacher
- Department of Molecular Genetics, The Ohio State University, Columbus, Ohio.,Department of Biological Chemistry and Pharmacology, The Ohio State University School of Medicine, Columbus, Ohio.,Center for Muscle Health and Neuromuscular Disorders, The Ohio State University and Nationwide Children's Hospital, Columbus, Ohio.,Center for RNA Biology, The Ohio State University, Columbus, Ohio
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8
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Yabe T, Hoshijima K, Yamamoto T, Takada S. Quadruple zebrafish mutant reveals different roles of Mesp genes in somite segmentation between mouse and zebrafish. Development 2016; 143:2842-52. [PMID: 27385009 DOI: 10.1242/dev.133173] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [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: 11/25/2015] [Accepted: 06/17/2016] [Indexed: 01/02/2023]
Abstract
The segmental pattern of somites is generated by sequential conversion of the temporal periodicity provided by the molecular clock. Whereas the basic structure of this clock is conserved among different species, diversity also exists, especially in terms of the molecular network. The temporal periodicity is subsequently converted into the spatial pattern of somites, and Mesp2 plays crucial roles in this conversion in the mouse. However, it remains unclear whether Mesp genes play similar roles in other vertebrates. In this study, we generated zebrafish mutants lacking all four zebrafish Mesp genes by using TALEN-mediated genome editing. Contrary to the situation in the mouse Mesp2 mutant, in the zebrafish Mesp quadruple mutant embryos the positions of somite boundaries were clearly determined and morphological boundaries were formed, although their formation was not completely normal. However, each somite was caudalized in a similar manner to the mouse Mesp2 mutant, and the superficial horizontal myoseptum and lateral line primordia were not properly formed in the quadruple mutants. These results clarify the conserved and species-specific roles of Mesp in the link between the molecular clock and somite morphogenesis.
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Affiliation(s)
- Taijiro Yabe
- Division of Molecular and Developmental Biology, Okazaki Institute for Integrative Bioscience and National Institute for Basic Biology, National Institutes of Natural Sciences, Okazaki, Aichi 444-8787, Japan Department for Basic Biology, SOKENDAI (The Graduate University for Advanced Studies), Okazaki, Aichi 444-8787, Japan
| | - Kazuyuki Hoshijima
- Department of Human Genetics, University of Utah, Salt Lake City, UT 84112, USA
| | - Takashi Yamamoto
- Department of Mathematical and Life Sciences, Graduate School of Science, Hiroshima University, Hiroshima 739-8526, Japan
| | - Shinji Takada
- Division of Molecular and Developmental Biology, Okazaki Institute for Integrative Bioscience and National Institute for Basic Biology, National Institutes of Natural Sciences, Okazaki, Aichi 444-8787, Japan Department for Basic Biology, SOKENDAI (The Graduate University for Advanced Studies), Okazaki, Aichi 444-8787, Japan
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9
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Abstract
Simple and efficient methods are presented for creating precise modifications of the zebrafish genome. Edited alleles are generated by homologous recombination between the host genome and double-stranded DNA (dsDNA) donor molecules, stimulated by the induction of double-strand breaks at targeted loci in the host genome. Because several kilobase-long tracts of sequence can be exchanged, multiple genome modifications can be generated simultaneously at a single locus. Methods are described for creating: (1) alleles with simple sequence changes or in-frame additions, (2) knockin/knockout alleles that express a reporter protein from an endogenous locus, and (3) conditional alleles in which exons are flanked by recombinogenic loxP sites. Significantly, our approach to genome editing allows the incorporation of a linked reporter gene into the donor sequences so that successfully edited alleles can be identified by virtue of expression of the reporter. Factors affecting the efficiency of genome editing are discussed, including the finding that dsDNA products of I-SceI meganuclease enzyme digestion are particularly effective as donor molecules for gene-editing events. Reagents and procedures are described for accomplishing efficient genome editing in the zebrafish.
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Affiliation(s)
- K Hoshijima
- University of Utah, Salt Lake City, UT, United States
| | - M J Jurynec
- University of Utah, Salt Lake City, UT, United States
| | - D J Grunwald
- University of Utah, Salt Lake City, UT, United States
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10
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Ota S, Hisano Y, Muraki M, Hoshijima K, Dahlem TJ, Grunwald DJ, Okada Y, Kawahara A. Efficient identification of TALEN-mediated genome modifications using heteroduplex mobility assays. Genes Cells 2013; 18:450-8. [PMID: 23573916 DOI: 10.1111/gtc.12050] [Citation(s) in RCA: 160] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2012] [Accepted: 02/18/2013] [Indexed: 01/24/2023]
Abstract
The heteroduplex mobility assay (HMA) is widely used to characterize strain variants of human viruses. To determine whether it can detect small sequence differences in homologous templates, we constructed a series of deletion constructs (1-10 bp deletions) in the multiple cloning site (MCS) of pBluescript II. After PCR amplification of the MCS using a mixture of wild-type and one of the deletion constructs, the resulting PCR amplicons were electrophoresed using 15% polyacrylamide gels. Two types of heteroduplexes exhibited retarded electrophoretic migration compared with individual homoduplexes. Therefore, we applied this HMA to detect transcription activator-like effector nucleases (TALEN)-induced insertion and/or deletion (indel) mutations at an endogenous locus. We found that TALEN in vivo activity was easily estimated by the degree of multiple HMA profiles derived from TALEN-injected F0 embryos. Furthermore, TALEN-injected F0 founder fish produced several unique HMA profiles in F1 embryos. Sequence analysis confirmed that the different HMA profiles contained distinct indel mutations. Thus, HMA is a rapid and sensitive analytical method for the detection of the TALEN-mediated genome modifications.
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Affiliation(s)
- Satoshi Ota
- Laboratory for Cardiovascular Molecular Dynamics, Quantitative Biology Center, RIKEN, Furuedai 6-2-3, Suita, Osaka 565-0874, Japan
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Ito Y, Kobayashi S, Nakamura N, Miyagi H, Esaki M, Hoshijima K, Hirose S. Close Association of Carbonic Anhydrase (CA2a and CA15a), Na(+)/H(+) Exchanger (Nhe3b), and Ammonia Transporter Rhcg1 in Zebrafish Ionocytes Responsible for Na(+) Uptake. Front Physiol 2013; 4:59. [PMID: 23565095 PMCID: PMC3615223 DOI: 10.3389/fphys.2013.00059] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [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: 10/03/2012] [Accepted: 03/12/2013] [Indexed: 02/03/2023] Open
Abstract
Freshwater (FW) fishes actively absorb salt from their environment to tolerate low salinities. We previously reported that vacuolar-type H+-ATPase/mitochondrion-rich cells (H-MRCs) on the skin epithelium of zebrafish larvae (Danio rerio) are primary sites for Na+ uptake. In this study, in an attempt to clarify the mechanism for the Na+ uptake, we performed a systematic analysis of gene expression patterns of zebrafish carbonic anhydrase (CA) isoforms and found that, of 12 CA isoforms, CA2a and CA15a are highly expressed in H-MRCs at larval stages. The ca2a and ca15a mRNA expression were salinity-dependent; they were upregulated in 0.03 mM Na+ water whereas ca15a but not ca2a was down-regulated in 70 mM Na+ water. Immunohistochemistry demonstrated cytoplasmic distribution of CA2a and apical membrane localization of CA15a. Furthermore, cell surface immunofluorescence staining revealed external surface localization of CA15a. Depletion of either CA2a or CA15a expression by Morpholino antisense oligonucleotides resulted in a significant decrease in Na+ accumulation in H-MRCs. An in situ proximity ligation assay demonstrated a very close association of CA2a, CA15a, Na+/H+ exchanger 3b (Nhe3b), and Rhcg1 ammonia transporter in H-MRC. Our findings suggest that CA2a, CA15a, and Rhcg1 play a key role in Na+uptake under FW conditions by forming a transport metabolon with Nhe3b.
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Affiliation(s)
- Yusuke Ito
- Department of Biological Sciences, Tokyo Institute of Technology Yokohama, Japan
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12
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Wang X, Kopinke D, Lin J, McPherson AD, Duncan RN, Otsuna H, Moro E, Hoshijima K, Grunwald DJ, Argenton F, Chien CB, Murtaugh LC, Dorsky RI. Wnt signaling regulates postembryonic hypothalamic progenitor differentiation. Dev Cell 2013; 23:624-36. [PMID: 22975330 DOI: 10.1016/j.devcel.2012.07.012] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2011] [Revised: 05/15/2012] [Accepted: 07/17/2012] [Indexed: 12/21/2022]
Abstract
Previous studies have raised the possibility that Wnt signaling may regulate both neural progenitor maintenance and neuronal differentiation within a single population. Here we investigate the role of Wnt/β-catenin activity in the zebrafish hypothalamus and find that the pathway is first required for the proliferation of unspecified hypothalamic progenitors in the embryo. At later stages, including adulthood, sequential activation and inhibition of Wnt activity is required for the differentiation of neural progenitors and negatively regulates radial glia differentiation. The presence of Wnt activity is conserved in hypothalamic progenitors of the adult mouse, where it plays a conserved role in inhibiting the differentiation of radial glia. This study establishes the vertebrate hypothalamus as a model for Wnt-regulated postembryonic neural progenitor differentiation and defines specific roles for Wnt signaling in neurogenesis.
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Affiliation(s)
- Xu Wang
- Department of Neurobiology and Anatomy, University of Utah, Salt Lake City, Utah 84112, USA
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13
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Xing L, Hoshijima K, Grunwald DJ, Fujimoto E, Quist TS, Sneddon J, Chien CB, Stevenson TJ, Bonkowsky JL. Zebrafish foxP2 zinc finger nuclease mutant has normal axon pathfinding. PLoS One 2012; 7:e43968. [PMID: 22937139 PMCID: PMC3427223 DOI: 10.1371/journal.pone.0043968] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2011] [Accepted: 07/30/2012] [Indexed: 11/18/2022] Open
Abstract
foxP2, a forkhead-domain transcription factor, is critical for speech and language development in humans, but its role in the establishment of CNS connectivity is unclear. While in vitro studies have identified axon guidance molecules as targets of foxP2 regulation, and cell culture assays suggest a role for foxP2 in neurite outgrowth, in vivo studies have been lacking regarding a role for foxP2 in axon pathfinding. We used a modified zinc finger nuclease methodology to generate mutations in the zebrafish foxP2 gene. Using PCR-based high resolution melt curve analysis (HRMA) of G0 founder animals, we screened and identified three mutants carrying nonsense mutations in the 2(nd) coding exon: a 17 base-pair (bp) deletion, an 8bp deletion, and a 4bp insertion. Sequence analysis of cDNA confirmed that these were frameshift mutations with predicted early protein truncations. Homozygous mutant fish were viable and fertile, with unchanged body morphology, and no apparent differences in CNS apoptosis, proliferation, or patterning at embryonic stages. There was a reduction in expression of the known foxP2 target gene cntnap2 that was rescued by injection of wild-type foxP2 transcript. When we examined axon pathfinding using a pan-axonal marker or transgenic lines, including a foxP2-neuron-specific enhancer, we did not observe any axon guidance errors. Our findings suggest that foxP2 is not necessary for axon pathfinding during development.
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Affiliation(s)
- Lingyan Xing
- Division of Pediatric Neurology, Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
- Department of Neurobiology and Anatomy, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
- Interdepartmental Program in Neurosciences, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
| | - Kazuyuki Hoshijima
- Department of Human Genetics, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
| | - David J. Grunwald
- Department of Human Genetics, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
| | - Esther Fujimoto
- Division of Pediatric Neurology, Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
| | - Tyler S. Quist
- Division of Pediatric Neurology, Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
| | - Jacob Sneddon
- Division of Pediatric Neurology, Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
| | - Chi-Bin Chien
- Department of Neurobiology and Anatomy, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
- Interdepartmental Program in Neurosciences, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
| | - Tamara J. Stevenson
- Division of Pediatric Neurology, Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
| | - Joshua L. Bonkowsky
- Division of Pediatric Neurology, Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
- Department of Neurobiology and Anatomy, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
- Interdepartmental Program in Neurosciences, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
- Department of Neurology, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
- * E-mail:
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Saito K, Nakamura N, Ito Y, Hoshijima K, Esaki M, Zhao B, Hirose S. Identification of zebrafish Fxyd11a protein that is highly expressed in ion-transporting epithelium of the gill and skin and its possible role in ion homeostasis. Front Physiol 2010; 1:129. [PMID: 21423371 PMCID: PMC3059942 DOI: 10.3389/fphys.2010.00129] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [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: 03/08/2010] [Accepted: 08/07/2010] [Indexed: 11/30/2022] Open
Abstract
FXYD proteins, small single-transmembrane proteins, have been proposed to be auxiliary regulatory subunits of Na+–K+-ATPase and have recently been implied in ion osmoregulation of teleost fish. In freshwater (FW) fish, numerous ions are actively taken up through mitochondrion-rich cells (MRCs) of the gill and skin epithelia, using the Na+ electrochemical gradient generated by Na+–K+-ATPase. In the present study, to understand the molecular mechanism for the regulation of Na+–K+-ATPase in MRCs of FW fish, we sought to identify FXYD proteins expressed in MRCs of zebrafish. Reverse-transcriptase PCR studies of adult zebrafish tissues revealed that, out of eight fxyd genes found in zebrafish database, only zebrafish fxyd11 (zfxyd11) mRNA exhibited a gill-specific expression. Double immunofluorescence staining showed that zFxyd11 is abundantly expressed in MRCs rich in Na+–K+-ATPase (NaK-MRCs) but not in those rich in vacuolar-type H+-transporting ATPase. An in situ proximity ligation assay demonstrated its close association with Na+–K+-ATPase in NaK-MRCs. The zfxyd11 mRNA expression was detectable at 1 day postfertilization, and its expression levels in the whole larvae and adult gills were regulated in response to changes in environmental ionic concentrations. Furthermore, knockdown of zFxyd11 resulted in a significant increase in the number of Na+–K+-ATPase–positive cells in the larval skin. These results suggest that zFxyd11 may regulate the transport ability of NaK-MRCs by modulating Na+–K+-ATPase activity, and may be involved in the regulation of body fluid and electrolyte homeostasis.
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Affiliation(s)
- Kaori Saito
- Department of Biological Sciences, Tokyo Institute of Technology Yokohama, Japan
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15
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Gribble SL, Nikolaus OB, Carver MS, Hoshijima K, Dorsky RI. Chromosomal position mediates spinal cord expression of a dbx1a enhancer. Dev Dyn 2010; 238:2929-35. [PMID: 19842185 DOI: 10.1002/dvdy.22122] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Dbx homeodomain proteins are important for the production of multiple spinal cord cell types. To examine the regulation of Dbx genes in more detail, we have generated transgenic zebrafish in which fluorescent protein expression is driven by predicted dbx1a enhancers. We identified three areas of sequence conservation upstream of the dbx1a coding sequence and generated fluorescent reporter constructs driven by these predicted enhancer elements and the endogenous dbx1a promoter. In multiple stable insertions of a 3.5-kb enhancer fragment, we observed that there was additional reporter expression in the dorsal spinal cord not normally observed by dbx1a in situ hybridization. In addition, these lines exhibited only transient reporter expression, unlike the endogenous gene. Surprisingly, a single insertion line expressed the reporter in the endogenous pattern, indicating that other local regulatory elements modulate gene expression through the 3.5-kb enhancer.
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Affiliation(s)
- Suzanna L Gribble
- Department of Neurobiology and Anatomy, University of Utah School of Medicine, Salt Lake City, Utah 84132-3401, USA
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Esaki M, Hoshijima K, Nakamura N, Munakata K, Tanaka M, Ookata K, Asakawa K, Kawakami K, Wang W, Weinberg ES, Hirose S. Mechanism of development of ionocytes rich in vacuolar-type H(+)-ATPase in the skin of zebrafish larvae. Dev Biol 2009; 329:116-29. [PMID: 19268451 DOI: 10.1016/j.ydbio.2009.02.026] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2008] [Revised: 02/23/2009] [Accepted: 02/24/2009] [Indexed: 11/17/2022]
Abstract
Mitochondrion-rich cells (MRCs), or ionocytes, play a central role in aquatic species, maintaining body fluid ionic homeostasis by actively taking up or excreting ions. Since their first description in 1932 in eel gills, extensive morphological and physiological analyses have yielded important insights into ionocyte structure and function, but understanding the developmental pathway specifying these cells remains an ongoing challenge. We previously succeeded in identifying a key transcription factor, Foxi3a, in zebrafish larvae by database mining. In the present study, we analyzed a zebrafish mutant, quadro (quo), deficient in foxi1 gene expression and found that foxi1 is essential for development of an MRC subpopulation rich in vacuolar-type H(+)-ATPase (vH-MRC). foxi1 acts upstream of Delta-Notch signaling that determines sporadic distribution of vH-MRC and regulates foxi3a expression. Through gain- and loss-of-function assays and cell transplantation experiments, we further clarified that (1) the expression level of foxi3a is maintained by a positive feedback loop between foxi3a and its downstream gene gcm2 and (2) Foxi3a functions cell-autonomously in the specification of vH-MRC. These observations provide a better understanding of the differentiation and distribution of the vH-MRC subtype.
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Affiliation(s)
- Masahiro Esaki
- Department of Biological Sciences, Tokyo Institute of Technology, Midori-ku, Yokohama, Japan
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17
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Toyoda Y, Hagiya Y, Adachi T, Hoshijima K, Kuo MT, Ishikawa T. MRP class of human ATP binding cassette (ABC) transporters: historical background and new research directions. Xenobiotica 2008; 38:833-62. [DOI: 10.1080/00498250701883514] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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18
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Tamura A, An R, Hagiya Y, Hoshijima K, Yoshida T, Mikuriya K, Ishikawa T. Drug-induced phototoxicity evoked by inhibition of human ABC transporter ABCG2: development ofin vitrohigh-speed screening systems. Expert Opin Drug Metab Toxicol 2008; 4:255-72. [DOI: 10.1517/17425255.4.3.255] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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Nakada T, Hoshijima K, Esaki M, Nagayoshi S, Kawakami K, Hirose S. Localization of ammonia transporter Rhcg1 in mitochondrion-rich cells of yolk sac, gill, and kidney of zebrafish and its ionic strength-dependent expression. Am J Physiol Regul Integr Comp Physiol 2007; 293:R1743-53. [PMID: 17686885 DOI: 10.1152/ajpregu.00248.2007] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Members of the Rh glycoprotein family have been shown to be involved in ammonia transport in a variety of species. Here we show that zebrafish Rhcg1, a member of the Rh glycoprotein family, is highly expressed in the yolk sac, gill, and renal tubules. Molecular cloning and characterization indicate that zebrafish Rhcg1 shares 82% sequence identity with the pufferfish ortholog fRhcg1. RT-PCR, combined with in situ hybridization, revealed that Rhcg1 is first expressed in vacuolar-type H+-ATPase/mitochondrion-rich cells (vH-MRC) on the yolk sac of larvae at 3 days postfertilization (dpf) and later in vH-MRC-like cells in the gill at 4–5 dpf. Ammonia excretion from zebrafish larvae increased in parallel with the expression of Rhcg1. At larval stages, Rhcg1 mRNA was detected only on the yolk sac and gill; however, the kidney, as well as the gill, becomes a major site of Rhcg1 expression in adults. Using a zebrafish Tol2 transgenic line whose vH-MRC are labeled with green fluorescent protein (GFP) and an antibody against zebrafish Rhcg1, we demonstrate that Rhcg1 is located in the apical regions of 1) vH-MRC on the yolk sac and vH-MRC-like cells (cell population with the expression of Rhcg1 and GFP) in the gill and 2) cells in the renal distal tubule and intercalated cell-like cells in the collecting duct of the kidney. Remarkably, expression of Rhcg1 mRNA at the larval stage was changed by environmental ionic strength. These results suggest that roles of zebrafish Rhcg1 are not solely ammonia secretion to eliminate nitrogen from the gill.
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Affiliation(s)
- Tsutomu Nakada
- Dept. of Biological Sciences, Tokyo Institute of Technology, 4259-B19 Nagatsuta-cho, Midori-ku, Yokohama-shi, Kanagawa-ken, 226-8501 Japan
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20
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Wakabayashi K, Nakagawa H, Tamura A, Koshiba S, Hoshijima K, Komada M, Ishikawa T. Intramolecular disulfide bond is a critical check point determining degradative fates of ATP-binding cassette (ABC) transporter ABCG2 protein. J Biol Chem 2007; 282:27841-6. [PMID: 17686774 DOI: 10.1074/jbc.c700133200] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Human ABCG2 belongs to the ATP-binding cassette (ABC) transporter family and plays an important role in various biological reactions, such as xenobiotic elimination and homeostasis of protoporphyrin. We previously reported that ABCG2 exists in the plasma membrane as a homodimer bound via a disulfide bond at Cys-603. In the present study, we examined the importance of an intramolecular disulfide bond for stability of the ABCG2 protein. Substitution of either Cys-592 or Cys-608 located in the extracellular loop to glycine resulted in a significant decrease in protein levels of ABCG2 when expressed in Flp-In-293 cells. Interestingly, the protein levels of those ABCG2 variants were remarkably enhanced by treatment with the proteasome inhibitor MG132. Concomitantly, increases in ubiquitinated forms of those variant proteins were detected by immunoprecipitation. In contrast, neither the protein level nor the ubiquitinated state of the ABCG2 wild-type (WT) was affected by MG132 treatment. Ubiquitin-mediated protein degradation is suggested to be involved in degradation of misfolded ABCG2 proteins lacking the intramolecular disulfide bond. On the other hand, the protein level of ABCG2 WT increased more than 4-fold when cells were treated with bafilomycin A(1), which inhibits lysosomal degradation, whereas the C592G or C608G variant was little affected by the same treatment. These results strongly suggest that two distinct pathways exist for protein degradation of ABCG2 WT and mutants lacking the intramolecular disulfide bond. Namely, the WT ABCG2 is degraded in lysosomes, and the misfolded ABCG2 lacking intramolecular disulfide bond undergoes ubiquitin-mediated protein degradation in proteasomes.
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Affiliation(s)
- Kanako Wakabayashi
- Department of Biomolecular Engineering, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama 226-8501, Japan
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Abstract
We tested the capability of the endocrine system in zebrafish to respond to environmental salinity challenges during larval stages. We reveal that the zebrafish larvae have a system in which several endocrine genes, including atrial natriuretic peptide (anp), renin, prolactin, growth hormone ( gh) and parathyroid hormone 1 (pth1), respond at the transcription level to changes in environmental salinity and that the responses are gene specific. Both anp and renin are upregulated in larvae raised in dilute freshwater medium but are downregulated in concentrated medium. On the other hand, expression of prolactin and gh is strongly enhanced in the dilute medium, but shows little or no change under higher salinity conditions. Interestingly, PTH1 expression depends on Ca(2+) concentration, as observed in mammals. Thus, taken together with the advantages of a model organism, including accessibility to genetic approaches, we propose that zebrafish larvae are useful for a comprehensive study of the regulatory mechanisms of the endocrine system in ionic and osmotic homeostasis.
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Affiliation(s)
- Kazuyuki Hoshijima
- Department of Biological Sciences, Tokyo Institute of Technology, 4259-B-19 Nagatsuta-cho, Midori-ku, Yokohama, Kanagawa 226-8501, Japan
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Tamura A, Onishi Y, An R, Koshiba S, Wakabayashi K, Hoshijima K, Priebe W, Yoshida T, Kometani S, Matsubara T, Mikuriya K, Ishikawa T. In Vitro Evaluation of Photosensitivity Risk Related to Genetic Polymorphisms of Human ABC Transporter ABCG2 and Inhibition by Drugs. Drug Metab Pharmacokinet 2007; 22:428-40. [DOI: 10.2133/dmpk.22.428] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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23
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Adachi T, Nakagawa H, Chung I, Hagiya Y, Hoshijima K, Noguchi N, Kuo MT, Ishikawa T. Nrf2-dependent and -independent induction of ABC transporters ABCC1, ABCC2, and ABCG2 in HepG2 cells under oxidative stress. J Exp Ther Oncol 2007; 6:335-348. [PMID: 18038766] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Nrf2, an NF-E2-related transcription factor, plays a critical role in transcriptional upregulation of many target genes, including those for metabolizing enzymes and transporters essential for cellular defense in response to oxidative and/or electrophilic stress. In the present study, we have studied the potential involvement of Nrf2 in induction of human ABC transporter genes under oxidative stress. We created a real-time PCR primer set to quantitatively investigate the induction of human ABC transporters by a redox-active compound tert-butylhydroquinone (tBHQ) in HepG2 cells. We found that mRNA levels of ABCC1, ABCC2, ABCC3, and ABCG2 were significantly elevated in dose- and time-dependent manners. Translocation of Nrf2 into the nuclei occurred concomitantly with the induction of ABCC1 and ABCC2 as well as both heavy and light chains of gamma-glutamylcysteine synthetase (gamma-GCSh and gamma-GCSI) during tBHQ treatments. To examine the potential involvement of Nrf2 in upregulation of the ABC transporters, we treated cells with siRNA to knockdown the expression of Nrf2. Under such Nrf2-knockdown conditions, tBHQ-induced mRNA levels of ABCC2 and ABCG2 were significantly suppressed as were mRNA levels of gamma-GCSh and gamma-GCSI. Interestingly, however, the elevated mRNA level of ABCC1 was little affected by Nrf2 siRNA treatment. We also addressed the involvement of Keap1, which is a negative regulator of Nrf2 by retrieving it in the cytoplasm. When HepG2 cells were treated with Keap1-specifc siRNA, a significant increase was observed in mRNA levels of ABCC1, ABCC2, and ABCG2 as well as gamma-GCSI, suggesting that induction of ABCC2 and ABCG2 by tBHQ is mediated by the Nrf2/Keap1 system, whereas the induction of ABCC1 may involve a Keap1-dependent but Nrf2-independent mechanism.
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Affiliation(s)
- Tatsuhiko Adachi
- Department of Biomolecular Engineering, Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, 4259-B-60 Nagatsuta-cho, Midori-ku, Yokohama 226-8501, Japan
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Esaki M, Hoshijima K, Kobayashi S, Fukuda H, Kawakami K, Hirose S. Visualization in zebrafish larvae of Na(+) uptake in mitochondria-rich cells whose differentiation is dependent on foxi3a. Am J Physiol Regul Integr Comp Physiol 2006; 292:R470-80. [PMID: 16946087 DOI: 10.1152/ajpregu.00200.2006] [Citation(s) in RCA: 97] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Uptake of Na(+) from the environment is an indispensable strategy for the survival of freshwater fish, as they easily lose Na(+) from the plasma to a diluted environment. Nevertheless, the location of and molecules involved in Na(+) uptake remain poorly understood. In this study, we utilized Sodium Green, a Na(+)-dependent fluorescent reagent, to provide direct evidence that Na(+) absorption takes place in a subset of the mitochondria-rich (MR) cells on the yolk sac surface of zebrafish larvae. Combined with immunohistochemistry, we revealed that the Na(+)-absorbing MR cells were exceptionally rich in vacuolar-type H(+)-ATPase (H(+)-ATPase) but moderately rich in Na(+)-K(+)-ATPase. We also addressed the function of foxi3a, a transcription factor that is specifically expressed in the H(+)-ATPase-rich MR cells. When foxi3a was depleted from zebrafish embryos by antisense morpholino oligonucleotide injection, differentiation of the MR cells was completely blocked and Na(+) influx was severely reduced, indicating that MR cells are the primary sites for Na(+) absorption. Additionally, foxi3a expression is initiated at the gastrula stage in the presumptive ectoderm; thus, we propose that foxi3a is a key gene in the control of MR cell differentiation. We also utilized a set of ion transport inhibitors to assess the molecules involved in the process and discuss the observations.
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Affiliation(s)
- Masahiro Esaki
- Department of Biological Sciences, Tokyo Institute of Technology, 4259-B-19 Nagatsuta-cho, Midori-ku, Yokohama 226-8501, Japan
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25
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Nag K, Kato A, Nakada T, Hoshijima K, Mistry AC, Takei Y, Hirose S. Molecular and functional characterization of adrenomedullin receptors in pufferfish. Am J Physiol Regul Integr Comp Physiol 2006; 290:R467-78. [PMID: 16195494 DOI: 10.1152/ajpregu.00507.2005] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The receptors for the calcitonin gene-related peptide (CGRP)/adrenomedullin (AM) family peptides were characterized in the mefugu Takifugu obscurus, a euryhaline fugu species very close to Takifugu rubripes, which has as many as five adrenomedullin genes (AM1–5). CGRP and AM share a G protein-coupled core receptor called calcitonin receptor-like receptor (CLR), and the specificity of the CLR is determined by the interaction with receptor activity-modifying proteins (RAMPs). Through database mining, three CLRs (CLR1–3) and five RAMPs (RAMP1–5) were identified, and all of them were cloned by RT-PCR and characterized by functional expression in COS7 cells in every possible combination of CLR-RAMP. The following combinations generated cAMP in response to physiological concentrations of CGRP, AM1 (an ortholog of mammalian AM), AM2, and AM5: CLR1-RAMP1/4 (CGRP), CLR1-RAMP2/3/5 (AM1), CLR2-RAMP2 (AM1), CLR1-RAMP3 (AM2), and CLR1-RAMP3 (AM5). Their expressions were found by Northern blot analysis to be tissue specific and salinity dependent. For example, CLR1-RAMP5 and CLR1-RAMP2 are expressed specifically in the gill and kidney, respectively, suggesting their involvement in osmoregulation. Furthermore, relatively high levels of CLRs and RAMPs were found in the spleen and ovary, suggesting roles in the immune and female reproductive systems. Immunohistochemistry revealed that AM receptors of the following types are expressed in the locations, indicated in brackets, of the mefugu gill and kidney: CLR1-RAMP5 (interlamellar vessels), CLR2-RAMP2 (pillar cells), and CLR1-RAMP2 (apical side of renal proximal tubule cells).
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Affiliation(s)
- Kakon Nag
- Department of Biological Sciences, Tokyo Institute of Technology,Yokohama 226-8501, Japan
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Goering LM, Hoshijima K, Hug B, Bisgrove B, Kispert A, Grunwald DJ. An interacting network of T-box genes directs gene expression and fate in the zebrafish mesoderm. Proc Natl Acad Sci U S A 2003; 100:9410-5. [PMID: 12883008 PMCID: PMC170932 DOI: 10.1073/pnas.1633548100] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
T-box genes encode transcription factors that play critical roles in generating the vertebrate body plan. In many developmental fields, multiple T-box genes are expressed in overlapping domains, establishing broad regions in which different combinations of T-box genes are coexpressed. Here we demonstrate that three T-box genes expressed in the zebrafish mesoderm, no tail, spadetail, and tbx6, operate as a network of interacting genes to regulate region-specific gene expression and developmental fate. Loss-of-function and gain-of-function genetic analyses reveal three kinds of interactions among the T-box genes: combinatorial interactions that generate new regulatory functions, additive contributions to common developmental pathways, and competitive antagonism governing downstream gene expression. We propose that T-box genes, like Hox genes, often function within gene networks comprised of related family members.
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Affiliation(s)
- Lisa M Goering
- Department of Human Genetics, University of Utah School of Medicine, Salt Lake City, UT 84112, USA
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Abstract
Although the vertebrate embryonic midline plays a critical role in determining the left/right asymmetric development of multiple organs, few genes expressed in the midline are known to function specifically in establishing laterality patterning. Here we show that a gene encoding protein disulfide isomerase P5 (PDI-P5) is expressed at high levels in the organizer and axial mesoderm and is required for establishing left/right asymmetries in the zebrafish embryo. pdi-p5 was discovered in a screen to detect genes down-regulated in the zebrafish midline mutant one-eyed pinhead and expressed predominantly in midline tissues of wild-type embryos. Depletion of the pdi-p5 product with morpholino antisense oligonucleotides results in loss of the asymmetric development of the heart, liver, pancreas, and gut. In addition, PDI-P5 depletion results in bilateral expression of all genes known to be expressed asymmetrically in the lateral plate mesoderm and the brain during embryogenesis. The laterality defects caused by pdi-p5 antisense treatment arise solely due to loss of the PDI-P5 protein, as they are reversed when treated embryos are supplied with an exogenous source of the PDI-P5 protein. Thus the spectrum of laterality defects resulting from depletion of the PDI-P5 protein fully recapitulates that resulting from loss of the midline. As loss of PDI-P5 does not appear to interfere with other aspects of midline development or function, we propose that PDI-P5 is specifically involved in the production of midline-derived signals required to establish left/right asymmetry.
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Affiliation(s)
- Kazuyuki Hoshijima
- Department of Human Genetics, University of Utah, Salt Lake City, Utah 84112, USA
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Fields MJ, Hoshijima K, Feng AH, Richardson WJ, Myers BS. A biomechanical, radiologic, and clinical comparison of outcome after multilevel cervical laminectomy or laminoplasty in the rabbit. Spine (Phila Pa 1976) 2000; 25:2925-31. [PMID: 11074681 DOI: 10.1097/00007632-200011150-00015] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
STUDY DESIGN A rabbit model was used to compare clinical outcome, radiographic changes, and biomechanical flexibility after cervical laminectomy and open-door laminoplasty. OBJECTIVE This study tested the hypothesis that radiographic changes and biomechanical flexibility could explain the differences in clinical outcome after cervical laminectomy and laminoplasty. SUMMARY OF BACKGROUND DATA Although multilevel cervical laminoplasty is thought to have advantages over cervical laminectomy, clinical outcome studies have been contradictory, and no experimental study has examined the possible mechanisms for the differences after healing. METHODS Twenty-four New Zealand White rabbits were randomized into four groups: normal, sham, C3-C6 wide laminectomy, and C3-C6 open-door laminoplasty. Clinical, radiographic, and biomechanical data were collected and compared up to 3 months after surgery. RESULTS Laminectomy had a statistically significant poorer clinical outcome when compared with laminoplasty after 3 months of healing. Radiologic analysis showed statistically significant angular deformity in the laminectomy group compared with laminoplasty and control groups at 3 months. In contrast, biomechanical measures of flexibility, neutral zone, and range of motion showed only small differences between any of the groups at any time. CONCLUSIONS The presence of deformity, and not a change in flexibility, is responsible for the differences in clinical outcome observed after laminectomy compared with laminoplasty in this model.
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Affiliation(s)
- M J Fields
- Department of Biomedical Engineering, Duke University, Durham, North Carolina 27708-0281, USA
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Abstract
This study determined the ability of an upper extremity Tarlov scale, a lower extremity Tarlov scale, and the Durham scale to predict the development of myelopathy and the likelihood of survival in a rabbit model of surgical treatments for cervical spondylotic myelopathy. Forty-eight rabbits were evaluated using the scales after cervical spinal surgery. Logistic regression analysis revealed that all three scales could predict the occurrence of myelopathy. However, only the Durham and lower extremity Tarlov scales also predicted the likelihood of survival. The Durham scale is offered as a useful predictor of myelopathy and survival in an animal model of surgical treatments for cervical spondylotic myelopathy. The lower extremity Tarlov scale is also a useful predictor of outcome; however, the upper extremity Tarlov scale is not recommended.
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Affiliation(s)
- M J Fields
- Department of Biomedical Engineering, Duke University, Durham, North Carolina 27708-0281, USA
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Hoshijima K, Nightingale RW, Yu JR, Richardson WJ, Harper KD, Yamamoto H, Myers BS. Strength and stability of posterior lumbar interbody fusion. Comparison of titanium fiber mesh implant and tricortical bone graft. Spine (Phila Pa 1976) 1997; 22:1181-8. [PMID: 9201853 DOI: 10.1097/00007632-199706010-00002] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
STUDY DESIGN A paired comparison was done of the bending flexibility and compression strength of tricortical bone graft and titanium fiber mesh implants in a human cadaver model of posterior lumbar interbody fusion. OBJECTIVES To test the hypothesis that a titanium fiber mesh implant and a tricortical bone graft provide adequate and equal mechanical strength and stability in posterior lumbar interbody fusion constructs. SUMMARY OF BACKGROUND DATA Although studies of posterior lumbar interbody fusion constructs have been performed, the authors are unaware of any study in which the strength and stability of a titanium fiber mesh implant are compared with those of tricortical bone graft for posterior lumbar interbody fusion in the human cadaver lumbar spine. METHODS Changes in neutral zone and range of motion were measured in a bending flexibility test before and after placement of posterior lumbar interbody fusion constructs. Tricortical bone graft and titanium fiber mesh implant construct stability than were compared in a paired analysis. The constructs than were loaded to failure to evaluate construct strength as a function of graft material and bone mineral density. RESULTS The posterior lumbar interbody fusion procedure produced statistically significant decreases in neutral zone when compared with the intact spine. No statistically significant differences in neutral zone, range of motion, or strength were detected between the two implants. Construct strength correlated strongly with bone mineral density. CONCLUSIONS Posterior lumbar interbody fusion procedures result in equal or improved acute stability for titanium fiber mesh implants and tricortical bone graft implants when used without additional posterior stabilization.
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Hoshijima K, Kohyama A, Watakabe I, Inoue K, Sakamoto H, Shimura Y. Transcriptional regulation of the Sex-lethal gene by helix-loop-helix proteins. Nucleic Acids Res 1995; 23:3441-8. [PMID: 7567454 PMCID: PMC307222 DOI: 10.1093/nar/23.17.3441] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Somatic sex determination in Drosophila depends on the expression of Sex-lethal (Sxl), whose level is determined by the relative number of X chromosomes and sets of autosomes (X:A ratio). The first step in regulation of Sxl expression is transcriptional control from its early promoter and several genes encoding transcription factors of the helix-loop-helix (HLH) family such as daughterless (da), sisterless-b (sis-b), deadpan (dpn) and extramacrochaetae (emc) have been implicated. By the use of transfection assays and in vitro binding experiments, here we show that da/sis-b heterodimers bind several sites on the Sxl early promoter with different affinities and consequently tune the level of active transcription from this promoter. Interestingly, our data indicate that repression by the dpn product of da/sis-b dependent activation results from specific binding of dpn protein to a unique site within the promoter. This contrasts with the mode of emc repression, which inhibits the formation of the da/sis-b heterodimers. These results reveal the molecular mechanisms by which Sxl gene transcription is positively or negatively regulated to control somatic sex determination.
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Affiliation(s)
- K Hoshijima
- Department of Biophysics, Faculty of Science, Kyoto University, Japan
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Inoue K, Hoshijima K, Higuchi I, Sakamoto H, Shimura Y. Binding of the Drosophila transformer and transformer-2 proteins to the regulatory elements of doublesex primary transcript for sex-specific RNA processing. Proc Natl Acad Sci U S A 1992; 89:8092-6. [PMID: 1518835 PMCID: PMC49862 DOI: 10.1073/pnas.89.17.8092] [Citation(s) in RCA: 122] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Sex-specific alternative processing of double-sex (dsx) precursor messenger RNA (pre-mRNA) is one of the key steps that regulates somatic sexual differentiation in Drosophila melanogaster. By transfection analyses using dsx minigene constructs, we identified six copies of the 13-nucleotide sequences TC(T/A)(T/A)C(A/G)ATCAACA in the female-specific fourth exon that act as the cis elements for the female-specific splicing of dsx pre-mRNA. UV-crosslinking experiments revealed that both female-specific transformer (tra) and transformer-2 (tra-2) products bind to the 13-nucleotide sequences of dsx pre-mRNA. These results strongly suggest that the female-specific splicing of dsx pre-mRNA is activated by binding of these proteins to the 13-nucleotide sequences.
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Affiliation(s)
- K Inoue
- Department of Biophysics, Faculty of Science, Kyoto University, Japan
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Abstract
Sex-specific alternative processing of doublesex (dsx) precursor messenger RNA (pre-mRNA) regulates somatic sexual differentiation in Drosophila melanogaster. Cotransfection analyses in which the dsx gene and the female-specific transformer (tra) and transformer-2 (tra-2) complementary DNAs were expressed in Drosophila Kc cells revealed that female-specific splicing of the dsx transcript was positively regulated by the products of the tra and tra-2 genes. Furthermore, analyses of mutant constructs of dsx showed that a portion of the female-specific exon sequence was required for regulation of dsx pre-messenger RNA splicing.
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Affiliation(s)
- K Hoshijima
- Department of Biophysics, Faculty of Science, Kyoto University, Japan
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Inoue K, Hoshijima K, Sakamoto H, Shimura Y. Binding of the Drosophila sex-lethal gene product to the alternative splice site of transformer primary transcript. Nature 1990; 344:461-3. [PMID: 1690860 DOI: 10.1038/344461a0] [Citation(s) in RCA: 251] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Somatic sexual differentiation in Drosophila melanogaster is accomplished by a hierarchy of genes of which one, Sex-lethal (Sxl), is required for the functional female-specific splicing of the transcripts of the immediately downstream regulatory gene, transformer (tra). The first exon of the tra primary transcript is spliced to one of two acceptor sites. Splicing to the upstream site yields a messenger RNA which is neither sex-specific nor functional, but that produced after splicing to the downstream acceptor site yields a functional female-specific mRNA. Here we address the question of how the Sxl gene product determines the alternative splicing of tra primary transcripts. One suggestion is that non-sex-specific splicing to the upstream acceptor is blocked in female flies by sex-specific factors, but neither the identity of the female-specific factors nor the mechanism of the blockage has been specified. We have now performed co-transfection experiments in which Sxl complementary DNA and the tra gene are expressed in Drosophila Kc cells. Moreover, we find that female Sxl-encoded protein binds specifically to the tra transcript at or near the non-sex-specific acceptor site, implying that the female Sxl gene product is the trans-acting factor that regulates the alternative splicing.
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Affiliation(s)
- K Inoue
- Department of Biophysics, Faculty of Science, Kyoto University, Japan
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Hoshijima K, Yamamoto H, Yamashita H. [Experimental studies of titanium fiber metal implant for spine fusion]. Nihon Seikeigeka Gakkai Zasshi 1988; 62:399-413. [PMID: 3404015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
For use as a graft in spine fusion, a titanium fiber metal implant (TFMI) from a woven pure titanium wire 250 micron in diameter was studied for its mechanical properties and biological fixation. Compression testing showed that the failure stress and modulus of elasticity of our implant closely resembled those previously reported fiber metals. It was, furthermore found that the pore-size distribution and mechanical properties of our TMFI were less variable than those of the products from kinked-and-cut wires. Repetitive-loading test showed a low permanent strain rate for TFMI, even with loads much greater than the failure stress of the vertebral body. Histologically and biomechanically, sufficient biological fixation was observed in the TMFI implanted lumbar vertebrae of adult mongrel dogs. According to these favorable results, TFMI could be an excellent biomaterial for spine fusion.
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Affiliation(s)
- K Hoshijima
- Department of Orthopaedic Surgery, Kochi Medical School
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Watanabe M, Takase N, Hoshijima K. [Simplified method for the determination of phenylpyruvic acid in the urine in experimental phenylketonuria in mice]. Igaku To Seibutsugaku 1965; 71:302-4. [PMID: 5894987] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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