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Wilkinson EL, Brennan LC, Harrison OJ, Crane‐Smith Z, Gautier P, Keighren MA, Budd P, Swaminathan K, Machesky LM, Allinson SL, Jackson IJ, Mort RL. Genetically engineered multicistronic allele of Pmel yielding highly specific CreERT2-mediated recombination in the melanocyte lineage. Pigment Cell Melanoma Res 2023; 36:71-77. [PMID: 36412082 PMCID: PMC10107733 DOI: 10.1111/pcmr.13076] [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: 07/15/2022] [Revised: 09/29/2022] [Accepted: 11/15/2022] [Indexed: 11/23/2022]
Abstract
Genetic approaches that allow lineage tracing are essential to our future understanding of melanocytes and melanoma. To date, the approaches used to label melanocytes in mice have relied on random integration of transgenes driven by the promoters of the Tyrosinase and Dopachrome tautomerase genes, knock-in to the Dopachrome tautomerase locus or knock-in to the Mlana locus in a bacterial artificial chromosome. These strategies result in expression in other tissues such as telencephalon and other cell types such as nerves. Here we used homologous recombination in mouse embryonic stem cells to generate a targeted multicistronic allele of the Pmel locus that drives melanocyte-specific expression of CreERT2, nuclear localised H2B-Cerulean and membrane localised marcks-mKate2 allowing live imaging of melanocytes and activation of other conditional alleles. We combined this allele with R26R-EYFP mice allowing induction of EYFP expression on administration of tamoxifen or its metabolite 4-OHT. The fluorescent proteins H2B-Cerulean and marcks-mKate2 label the cell nucleus and plasma membrane respectively allowing live imaging and FACS isolation of melanoblasts and melanocytes as well as serving to provide an internal control allowing estimation of recombination efficiency after administration of tamoxifen. We demonstrate the utility of the transgene in embryonic and adult tissues.
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Affiliation(s)
- Emma L. Wilkinson
- Division of Biomedical and Life Sciences, Faculty of Health and MedicineLancaster UniversityLancasterUK
| | - Louise C. Brennan
- Division of Biomedical and Life Sciences, Faculty of Health and MedicineLancaster UniversityLancasterUK
| | - Olivia J. Harrison
- MRC Human Genetics Unit, Institute of Genetics and Cancer, Western General HospitalUniversity of EdinburghEdinburghUK
| | - Zoe Crane‐Smith
- MRC Human Genetics Unit, Institute of Genetics and Cancer, Western General HospitalUniversity of EdinburghEdinburghUK
| | - Philippe Gautier
- MRC Human Genetics Unit, Institute of Genetics and Cancer, Western General HospitalUniversity of EdinburghEdinburghUK
| | - Margaret A. Keighren
- MRC Human Genetics Unit, Institute of Genetics and Cancer, Western General HospitalUniversity of EdinburghEdinburghUK
| | - Peter Budd
- MRC Human Genetics Unit, Institute of Genetics and Cancer, Western General HospitalUniversity of EdinburghEdinburghUK
| | - Karthic Swaminathan
- Centre for Skin Sciences, Faculty of Life SciencesUniversity of BradfordBradfordUK
| | - Laura M. Machesky
- Cancer Research UK, Beatson Institute, and Institute of Cancer SciencesUniversity of GlasgowGlasgowUK
| | - Sarah L. Allinson
- Division of Biomedical and Life Sciences, Faculty of Health and MedicineLancaster UniversityLancasterUK
| | - Ian J. Jackson
- MRC Human Genetics Unit, Institute of Genetics and Cancer, Western General HospitalUniversity of EdinburghEdinburghUK
- Roslin InstituteUniversity of EdinburghRoslinUK
| | - Richard L. Mort
- Division of Biomedical and Life Sciences, Faculty of Health and MedicineLancaster UniversityLancasterUK
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2
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Quidwai T, Wang J, Hall EA, Petriman NA, Leng W, Kiesel P, Wells JN, Murphy LC, Keighren MA, Marsh JA, Lorentzen E, Pigino G, Mill P. A WDR35-dependent coat protein complex transports ciliary membrane cargo vesicles to cilia. eLife 2021; 10:e69786. [PMID: 34734804 PMCID: PMC8754431 DOI: 10.7554/elife.69786] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Accepted: 11/04/2021] [Indexed: 11/13/2022] Open
Abstract
Intraflagellar transport (IFT) is a highly conserved mechanism for motor-driven transport of cargo within cilia, but how this cargo is selectively transported to cilia is unclear. WDR35/IFT121 is a component of the IFT-A complex best known for its role in ciliary retrograde transport. In the absence of WDR35, small mutant cilia form but fail to enrich in diverse classes of ciliary membrane proteins. In Wdr35 mouse mutants, the non-core IFT-A components are degraded and core components accumulate at the ciliary base. We reveal deep sequence homology of WDR35 and other IFT-A subunits to α and ß' COPI coatomer subunits and demonstrate an accumulation of 'coat-less' vesicles that fail to fuse with Wdr35 mutant cilia. We determine that recombinant non-core IFT-As can bind directly to lipids and provide the first in situ evidence of a novel coat function for WDR35, likely with other IFT-A proteins, in delivering ciliary membrane cargo necessary for cilia elongation.
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Affiliation(s)
- Tooba Quidwai
- MRC Human Genetics Unit, Institute of Genetics and Cancer, University of EdinburghEdinburghUnited Kingdom
| | - Jiaolong Wang
- Department of Molecular Biology and Genetics, Aarhus UniversityAarhusDenmark
| | - Emma A Hall
- MRC Human Genetics Unit, Institute of Genetics and Cancer, University of EdinburghEdinburghUnited Kingdom
| | - Narcis A Petriman
- Department of Molecular Biology and Genetics, Aarhus UniversityAarhusDenmark
| | - Weihua Leng
- Max Planck Institute of Molecular Cell Biology and GeneticsDresdenGermany
| | - Petra Kiesel
- Max Planck Institute of Molecular Cell Biology and GeneticsDresdenGermany
| | - Jonathan N Wells
- MRC Human Genetics Unit, Institute of Genetics and Cancer, University of EdinburghEdinburghUnited Kingdom
| | - Laura C Murphy
- MRC Human Genetics Unit, Institute of Genetics and Cancer, University of EdinburghEdinburghUnited Kingdom
| | - Margaret A Keighren
- MRC Human Genetics Unit, Institute of Genetics and Cancer, University of EdinburghEdinburghUnited Kingdom
| | - Joseph A Marsh
- MRC Human Genetics Unit, Institute of Genetics and Cancer, University of EdinburghEdinburghUnited Kingdom
| | - Esben Lorentzen
- Department of Molecular Biology and Genetics, Aarhus UniversityAarhusDenmark
| | - Gaia Pigino
- Max Planck Institute of Molecular Cell Biology and GeneticsDresdenGermany
- Human TechnopoleMilanItaly
| | - Pleasantine Mill
- MRC Human Genetics Unit, Institute of Genetics and Cancer, University of EdinburghEdinburghUnited Kingdom
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3
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West JD, Tang PC, Everett CA, MacKay GE, Flockhart JH, Keighren MA. Re-evaluation of the causes of variation among mouse aggregation chimaeras. Biol Open 2019; 8:8/5/bio042804. [PMID: 31147312 PMCID: PMC6550066 DOI: 10.1242/bio.042804] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
The composition of adult mouse aggregation chimaeras is much more variable than X-inactivation mosaics. An early theoretical model proposed that almost all the extra variation in chimaeras arises, before X-inactivation occurs, by spatially constrained, geometrical allocation of inner cell mass (ICM) cells to the epiblast and primitive endoderm (PrE). However, this is inconsistent with more recent embryological evidence. Analysis of published results for chimaeric blastocysts and mid-gestation chimaeras suggested that some variation exists among chimaeric morulae and more variation arises both when morula cells are allocated to the ICM versus the trophectoderm (TE) and when ICM cells are allocated to the epiblast versus the PrE. Computer simulation results were also consistent with the conclusion that stochastic allocation of cells to blastocyst lineages in two steps, without the type of geometrical sampling that was originally proposed, could cause a wide variation in chimaeric epiblast composition. Later allocation events will cause additional variation among both chimaeras and X-inactivation mosaics. We also suggest that previously published U-shaped frequency distributions for chimaeric placenta composition might be explained by how TE cells are allocated to the polar TE and/or the subsequent movement of cells from polar TE to mural TE.
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Affiliation(s)
- John D West
- Genes and Development Group, Centre for Integrative Physiology, Clinical Sciences, University of Edinburgh Medical School, Hugh Robson Building, George Square, Edinburgh EH8 9XD, UK
| | - Pin-Chi Tang
- Genes and Development Group, Centre for Integrative Physiology, Clinical Sciences, University of Edinburgh Medical School, Hugh Robson Building, George Square, Edinburgh EH8 9XD, UK
| | - Clare A Everett
- Genes and Development Group, Centre for Integrative Physiology, Clinical Sciences, University of Edinburgh Medical School, Hugh Robson Building, George Square, Edinburgh EH8 9XD, UK
| | - Gillian E MacKay
- Genes and Development Group, Centre for Integrative Physiology, Clinical Sciences, University of Edinburgh Medical School, Hugh Robson Building, George Square, Edinburgh EH8 9XD, UK
| | - Jean H Flockhart
- Genes and Development Group, Centre for Integrative Physiology, Clinical Sciences, University of Edinburgh Medical School, Hugh Robson Building, George Square, Edinburgh EH8 9XD, UK
| | - Margaret A Keighren
- Genes and Development Group, Centre for Integrative Physiology, Clinical Sciences, University of Edinburgh Medical School, Hugh Robson Building, George Square, Edinburgh EH8 9XD, UK
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4
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Ford MJ, Yeyati PL, Mali GR, Keighren MA, Waddell SH, Mjoseng HK, Douglas AT, Hall EA, Sakaue-Sawano A, Miyawaki A, Meehan RR, Boulter L, Jackson IJ, Mill P, Mort RL. A Cell/Cilia Cycle Biosensor for Single-Cell Kinetics Reveals Persistence of Cilia after G1/S Transition Is a General Property in Cells and Mice. Dev Cell 2019; 47:509-523.e5. [PMID: 30458140 PMCID: PMC6251972 DOI: 10.1016/j.devcel.2018.10.027] [Citation(s) in RCA: 53] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2018] [Revised: 09/04/2018] [Accepted: 10/24/2018] [Indexed: 01/31/2023]
Abstract
The cilia and cell cycles are inextricably linked. Centrioles in the basal body of cilia nucleate the ciliary axoneme and sequester pericentriolar matrix (PCM) at the centrosome to organize the mitotic spindle. Cilia themselves respond to growth signals, prompting cilia resorption and cell cycle re-entry. We describe a fluorescent cilia and cell cycle biosensor allowing live imaging of cell cycle progression and cilia assembly and disassembly kinetics in cells and inducible mice. We define assembly and disassembly in relation to cell cycle stage with single-cell resolution and explore the intercellular heterogeneity in cilia kinetics. In all cells and tissues analyzed, we observed cilia that persist through the G1/S transition and into S/G2/M-phase. We conclude that persistence of cilia after the G1/S transition is a general property. This resource will shed light at an individual cell level on the interplay between the cilia and cell cycles in development, regeneration, and disease. Arl13bCerulean-Fucci2a biosensor labels the cell and cilia cycles Analysis of cells and mice reveals persistence of cilia after the G1/S transition Inducible mouse line allows lineage tracing and ex vivo live imaging Organisms can tolerate artificially lengthened cilia without overt phenotypes.
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Affiliation(s)
- Matthew J Ford
- MRC Human Genetics Unit, MRC Institute of Genetics & Molecular Medicine, University of Edinburgh, Western General Hospital, Edinburgh EH4 2XU, UK
| | - Patricia L Yeyati
- MRC Human Genetics Unit, MRC Institute of Genetics & Molecular Medicine, University of Edinburgh, Western General Hospital, Edinburgh EH4 2XU, UK
| | - Girish R Mali
- MRC Human Genetics Unit, MRC Institute of Genetics & Molecular Medicine, University of Edinburgh, Western General Hospital, Edinburgh EH4 2XU, UK
| | - Margaret A Keighren
- MRC Human Genetics Unit, MRC Institute of Genetics & Molecular Medicine, University of Edinburgh, Western General Hospital, Edinburgh EH4 2XU, UK
| | - Scott H Waddell
- MRC Human Genetics Unit, MRC Institute of Genetics & Molecular Medicine, University of Edinburgh, Western General Hospital, Edinburgh EH4 2XU, UK
| | - Heidi K Mjoseng
- MRC Human Genetics Unit, MRC Institute of Genetics & Molecular Medicine, University of Edinburgh, Western General Hospital, Edinburgh EH4 2XU, UK
| | - Adam T Douglas
- MRC Human Genetics Unit, MRC Institute of Genetics & Molecular Medicine, University of Edinburgh, Western General Hospital, Edinburgh EH4 2XU, UK
| | - Emma A Hall
- MRC Human Genetics Unit, MRC Institute of Genetics & Molecular Medicine, University of Edinburgh, Western General Hospital, Edinburgh EH4 2XU, UK
| | - Asako Sakaue-Sawano
- Centre of Brain Science, Laboratory for Cell Function and Dynamics, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Atsushi Miyawaki
- Centre of Brain Science, Laboratory for Cell Function and Dynamics, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Richard R Meehan
- MRC Human Genetics Unit, MRC Institute of Genetics & Molecular Medicine, University of Edinburgh, Western General Hospital, Edinburgh EH4 2XU, UK
| | - Luke Boulter
- MRC Human Genetics Unit, MRC Institute of Genetics & Molecular Medicine, University of Edinburgh, Western General Hospital, Edinburgh EH4 2XU, UK
| | - Ian J Jackson
- MRC Human Genetics Unit, MRC Institute of Genetics & Molecular Medicine, University of Edinburgh, Western General Hospital, Edinburgh EH4 2XU, UK; Roslin Institute, University of Edinburgh, Roslin EH25 9RG, UK
| | - Pleasantine Mill
- MRC Human Genetics Unit, MRC Institute of Genetics & Molecular Medicine, University of Edinburgh, Western General Hospital, Edinburgh EH4 2XU, UK.
| | - Richard L Mort
- Division of Biomedical and Life Sciences, Faculty of Health and Medicine, Lancaster University, Bailrigg, Furness Building, Lancaster LA1 4YG, UK.
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5
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Findlay AS, Carter RN, Starbuck B, McKie L, Nováková K, Budd PS, Keighren MA, Marsh JA, Cross SH, Simon MM, Potter PK, Morton NM, Jackson IJ. Mouse Idh3a mutations cause retinal degeneration and reduced mitochondrial function. Dis Model Mech 2018; 11:dmm.036426. [PMID: 30478029 PMCID: PMC6307916 DOI: 10.1242/dmm.036426] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Accepted: 11/12/2018] [Indexed: 01/23/2023] Open
Abstract
Isocitrate dehydrogenase (IDH) is an enzyme required for the production of α-ketoglutarate from isocitrate. IDH3 generates the NADH used in the mitochondria for ATP production, and is a tetramer made up of two α, one β and one γ subunit. Loss-of-function and missense mutations in both IDH3A and IDH3B have previously been implicated in families exhibiting retinal degeneration. Using mouse models, we investigated the role of IDH3 in retinal disease and mitochondrial function. We identified mice with late-onset retinal degeneration in a screen of ageing mice carrying an ENU-induced mutation, E229K, in Idh3a Mice homozygous for this mutation exhibit signs of retinal stress, indicated by GFAP staining, as early as 3 months, but no other tissues appear to be affected. We produced a knockout of Idh3a and found that homozygous mice do not survive past early embryogenesis. Idh3a-/E229K compound heterozygous mutants exhibit a more severe retinal degeneration compared with Idh3aE229K/E229K homozygous mutants. Analysis of mitochondrial function in mutant cell lines highlighted a reduction in mitochondrial maximal respiration and reserve capacity levels in both Idh3aE229K/E229K and Idh3a-/E229K cells. Loss-of-function Idh3b mutants do not exhibit the same retinal degeneration phenotype, with no signs of retinal stress or reduction in mitochondrial respiration. It has previously been reported that the retina operates with a limited mitochondrial reserve capacity and we suggest that this, in combination with the reduced reserve capacity in mutants, explains the degenerative phenotype observed in Idh3a mutant mice.This article has an associated First Person interview with the first author of the paper.
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Affiliation(s)
- Amy S Findlay
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Crewe Road, Edinburgh EH4 2XU, UK
| | - Roderick N Carter
- Molecular Metabolism Group, Centre for Cardiovascular Sciences, Queens Medical Research Institute, University of Edinburgh, Edinburgh EH16 4TJ, UK
| | - Becky Starbuck
- MRC Mammalian Genetics Unit, MRC Harwell Institute, Harwell Campus, Oxfordshire OX11 0RD, UK
| | - Lisa McKie
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Crewe Road, Edinburgh EH4 2XU, UK
| | - Klára Nováková
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Crewe Road, Edinburgh EH4 2XU, UK
| | - Peter S Budd
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Crewe Road, Edinburgh EH4 2XU, UK
| | - Margaret A Keighren
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Crewe Road, Edinburgh EH4 2XU, UK
| | - Joseph A Marsh
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Crewe Road, Edinburgh EH4 2XU, UK
| | - Sally H Cross
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Crewe Road, Edinburgh EH4 2XU, UK
| | - Michelle M Simon
- MRC Mammalian Genetics Unit, MRC Harwell Institute, Harwell Campus, Oxfordshire OX11 0RD, UK
| | - Paul K Potter
- MRC Mammalian Genetics Unit, MRC Harwell Institute, Harwell Campus, Oxfordshire OX11 0RD, UK
| | - Nicholas M Morton
- Molecular Metabolism Group, Centre for Cardiovascular Sciences, Queens Medical Research Institute, University of Edinburgh, Edinburgh EH16 4TJ, UK
| | - Ian J Jackson
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Crewe Road, Edinburgh EH4 2XU, UK .,Roslin Institute, University of Edinburgh, Edinburgh EH25 9RG, UK
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6
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Mali GR, Yeyati PL, Mizuno S, Dodd DO, Tennant PA, Keighren MA, Zur Lage P, Shoemark A, Garcia-Munoz A, Shimada A, Takeda H, Edlich F, Takahashi S, von Kreigsheim A, Jarman AP, Mill P. ZMYND10 functions in a chaperone relay during axonemal dynein assembly. eLife 2018; 7:34389. [PMID: 29916806 PMCID: PMC6044906 DOI: 10.7554/elife.34389] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [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: 12/15/2017] [Accepted: 06/18/2018] [Indexed: 11/13/2022] Open
Abstract
Molecular chaperones promote the folding and macromolecular assembly of a diverse set of 'client' proteins. How ubiquitous chaperone machineries direct their activities towards specific sets of substrates is unclear. Through the use of mouse genetics, imaging and quantitative proteomics we uncover that ZMYND10 is a novel co-chaperone that confers specificity for the FKBP8-HSP90 chaperone complex towards axonemal dynein clients required for cilia motility. Loss of ZMYND10 perturbs the chaperoning of axonemal dynein heavy chains, triggering broader degradation of dynein motor subunits. We show that pharmacological inhibition of FKBP8 phenocopies dynein motor instability associated with the loss of ZMYND10 in airway cells and that human disease-causing variants of ZMYND10 disrupt its ability to act as an FKBP8-HSP90 co-chaperone. Our study indicates that primary ciliary dyskinesia (PCD), caused by mutations in dynein assembly factors disrupting cytoplasmic pre-assembly of axonemal dynein motors, should be considered a cell-type specific protein-misfolding disease.
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Affiliation(s)
- Girish R Mali
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, United Kingdom
| | - Patricia L Yeyati
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, United Kingdom
| | - Seiya Mizuno
- Laboratory Animal Resource Centre, University of Tsukuba, Tsukuba, Japan
| | - Daniel O Dodd
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, United Kingdom
| | - Peter A Tennant
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, United Kingdom
| | - Margaret A Keighren
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, United Kingdom
| | - Petra Zur Lage
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Amelia Shoemark
- Division of Molecular and Clinical Medicine, University of Dundee, Dundee, United Kingdom
| | | | - Atsuko Shimada
- Department of Biological Sciences, University of Tokyo, Tokyo, Japan
| | - Hiroyuki Takeda
- Department of Biological Sciences, University of Tokyo, Tokyo, Japan
| | - Frank Edlich
- Institute for Biochemistry and Molecular Biology, University of Freiburg, Freiburg, Germany.,BIOSS, Centre for Biological Signaling Studies, University of Freiburg, Freiburg, Germany
| | - Satoru Takahashi
- Laboratory Animal Resource Centre, University of Tsukuba, Tsukuba, Japan.,Department of Anatomy and Embryology, Faculty of Medicine, University of Tsukuba, Tsukuba, Japan
| | - Alex von Kreigsheim
- Systems Biology Ireland, University College Dublin, Dublin, Ireland.,Edinburgh Cancer Research UK Centre, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, United Kingdom
| | - Andrew P Jarman
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Pleasantine Mill
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, United Kingdom
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7
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Abstract
It has been shown previously that BALB/c strain embryos tend to contribute poorly to mouse aggregation chimaeras. In the present study we showed that BALB/c cells were not preferentially allocated to any extraembryonic lineages of mouse aggregation chimaeras, but their contribution decreased during the early postimplantation period and they were significantly depleted by E8.5. The development of BALB/c strain preimplantation embryos lagged behind embryos from some other strains and the contribution that BALB/c and other embryos made to chimaeras correlated with their developmental stage at E2.5. This relationship suggests that the poor contribution of BALB/c embryos to aggregation chimaeras is at least partly a consequence of generalised selection related to slow or delayed preimplantation development. The suitability of BALB/c embryos for maximising the ES cell contribution to mouse ES cell chimaeras is also discussed. Summary: BALB/c strain embryos contributed poorly to mouse aggregation chimaeras by E8.5. Selection appears linked to slow BALB/c development and might also explain the good ES cell contribution in BALB/c↔ES-cell chimaeras.
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Affiliation(s)
- Pin-Chi Tang
- Genes and Development Group, Centre for Integrative Physiology, Clinical Sciences, University of Edinburgh Medical School, Hugh Robson Building, George Square, Edinburgh, EH8 9XD, UK.,Obstetrics and Gynaecology Section, Clinical Sciences, University of Edinburgh Medical School, The Queen's Medical Research Institute, 47 Little France Crescent, Edinburgh, EH16 4TJ, UK
| | - Gillian E MacKay
- Genes and Development Group, Centre for Integrative Physiology, Clinical Sciences, University of Edinburgh Medical School, Hugh Robson Building, George Square, Edinburgh, EH8 9XD, UK.,Obstetrics and Gynaecology Section, Clinical Sciences, University of Edinburgh Medical School, The Queen's Medical Research Institute, 47 Little France Crescent, Edinburgh, EH16 4TJ, UK
| | - Jean H Flockhart
- Genes and Development Group, Centre for Integrative Physiology, Clinical Sciences, University of Edinburgh Medical School, Hugh Robson Building, George Square, Edinburgh, EH8 9XD, UK.,Obstetrics and Gynaecology Section, Clinical Sciences, University of Edinburgh Medical School, The Queen's Medical Research Institute, 47 Little France Crescent, Edinburgh, EH16 4TJ, UK
| | - Margaret A Keighren
- Genes and Development Group, Centre for Integrative Physiology, Clinical Sciences, University of Edinburgh Medical School, Hugh Robson Building, George Square, Edinburgh, EH8 9XD, UK.,Obstetrics and Gynaecology Section, Clinical Sciences, University of Edinburgh Medical School, The Queen's Medical Research Institute, 47 Little France Crescent, Edinburgh, EH16 4TJ, UK
| | - Anna Kopakaki
- Obstetrics and Gynaecology Section, Clinical Sciences, University of Edinburgh Medical School, The Queen's Medical Research Institute, 47 Little France Crescent, Edinburgh, EH16 4TJ, UK
| | - John D West
- Genes and Development Group, Centre for Integrative Physiology, Clinical Sciences, University of Edinburgh Medical School, Hugh Robson Building, George Square, Edinburgh, EH8 9XD, UK .,Obstetrics and Gynaecology Section, Clinical Sciences, University of Edinburgh Medical School, The Queen's Medical Research Institute, 47 Little France Crescent, Edinburgh, EH16 4TJ, UK
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8
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Hall EA, Nahorski MS, Murray LM, Shaheen R, Perkins E, Dissanayake KN, Kristaryanto Y, Jones RA, Vogt J, Rivagorda M, Handley MT, Mali GR, Quidwai T, Soares DC, Keighren MA, McKie L, Mort RL, Gammoh N, Garcia-Munoz A, Davey T, Vermeren M, Walsh D, Budd P, Aligianis IA, Faqeih E, Quigley AJ, Jackson IJ, Kulathu Y, Jackson M, Ribchester RR, von Kriegsheim A, Alkuraya FS, Woods CG, Maher ER, Mill P. PLAA Mutations Cause a Lethal Infantile Epileptic Encephalopathy by Disrupting Ubiquitin-Mediated Endolysosomal Degradation of Synaptic Proteins. Am J Hum Genet 2017; 100:706-724. [PMID: 28413018 PMCID: PMC5420347 DOI: 10.1016/j.ajhg.2017.03.008] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2017] [Accepted: 03/17/2017] [Indexed: 12/12/2022] Open
Abstract
During neurotransmission, synaptic vesicles undergo multiple rounds of exo-endocytosis, involving recycling and/or degradation of synaptic proteins. While ubiquitin signaling at synapses is essential for neural function, it has been assumed that synaptic proteostasis requires the ubiquitin-proteasome system (UPS). We demonstrate here that turnover of synaptic membrane proteins via the endolysosomal pathway is essential for synaptic function. In both human and mouse, hypomorphic mutations in the ubiquitin adaptor protein PLAA cause an infantile-lethal neurodysfunction syndrome with seizures. Resulting from perturbed endolysosomal degradation, Plaa mutant neurons accumulate K63-polyubiquitylated proteins and synaptic membrane proteins, disrupting synaptic vesicle recycling and neurotransmission. Through characterization of this neurological intracellular trafficking disorder, we establish the importance of ubiquitin-mediated endolysosomal trafficking at the synapse.
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Affiliation(s)
- Emma A Hall
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh EH4 2XU, UK
| | - Michael S Nahorski
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge CB2 OXY, UK; Department of Medical Genetics, University of Cambridge, and Cambridge NIHR Biomedical Research Centre, Cambridge Biomedical Campus, Cambridge CB2 OXY, UK
| | - Lyndsay M Murray
- Centre for Integrative Physiology, University of Edinburgh, Edinburgh EH8 9XD, UK; Euan McDonald Centre for Motor Neuron Disease Research, University of Edinburgh, Edinburgh EH16 4SB, UK
| | - Ranad Shaheen
- Department of Genetics, King Faisal Specialist Hospital and Research Center, Riyadh 11211, Saudi Arabia
| | - Emma Perkins
- Centre for Integrative Physiology, University of Edinburgh, Edinburgh EH8 9XD, UK; Euan McDonald Centre for Motor Neuron Disease Research, University of Edinburgh, Edinburgh EH16 4SB, UK
| | - Kosala N Dissanayake
- Euan McDonald Centre for Motor Neuron Disease Research, University of Edinburgh, Edinburgh EH16 4SB, UK; Patrick Wild Centre, University of Edinburgh, Edinburgh EH8 9XD, UK; Centre for Cognitive and Neural Systems, University of Edinburgh, Edinburgh EH8 9JZ, UK
| | - Yosua Kristaryanto
- MRC Protein Phosphorylation and Ubiquitylation Unit, University of Dundee, Dundee DD1 5EH, UK
| | - Ross A Jones
- Centre for Integrative Physiology, University of Edinburgh, Edinburgh EH8 9XD, UK; Euan McDonald Centre for Motor Neuron Disease Research, University of Edinburgh, Edinburgh EH16 4SB, UK
| | - Julie Vogt
- West Midlands Regional Genetics Service, Clinical Genetics Unit, Birmingham Women's Hospital, Birmingham B15 2TG, UK
| | - Manon Rivagorda
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh EH4 2XU, UK
| | - Mark T Handley
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh EH4 2XU, UK
| | - Girish R Mali
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh EH4 2XU, UK
| | - Tooba Quidwai
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh EH4 2XU, UK
| | - Dinesh C Soares
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh EH4 2XU, UK; Centre for Genomic and Experimental Medicine, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh EH4 2XU, UK
| | - Margaret A Keighren
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh EH4 2XU, UK
| | - Lisa McKie
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh EH4 2XU, UK
| | - Richard L Mort
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh EH4 2XU, UK
| | - Noor Gammoh
- Edinburgh Cancer Research UK Centre, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh EH4 2XU, UK
| | | | - Tracey Davey
- Electron Microscopy Research Services, Newcastle University, Newcastle NE2 4HH, UK
| | - Matthieu Vermeren
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh EH4 2XU, UK
| | - Diana Walsh
- West Midlands Regional Genetics Service, Clinical Genetics Unit, Birmingham Women's Hospital, Birmingham B15 2TG, UK
| | - Peter Budd
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh EH4 2XU, UK
| | - Irene A Aligianis
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh EH4 2XU, UK
| | - Eissa Faqeih
- Department of Pediatric Subspecialties, Children's Hospital, King Fahad Medical City, Riyadh 11211, Saudi Arabia
| | - Alan J Quigley
- NHS Lothian, Department of Paediatric Radiology, Royal Hospital for Sick Children, Edinburgh EH9 1LF, UK
| | - Ian J Jackson
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh EH4 2XU, UK
| | - Yogesh Kulathu
- MRC Protein Phosphorylation and Ubiquitylation Unit, University of Dundee, Dundee DD1 5EH, UK
| | - Mandy Jackson
- Centre for Integrative Physiology, University of Edinburgh, Edinburgh EH8 9XD, UK; Euan McDonald Centre for Motor Neuron Disease Research, University of Edinburgh, Edinburgh EH16 4SB, UK
| | - Richard R Ribchester
- Euan McDonald Centre for Motor Neuron Disease Research, University of Edinburgh, Edinburgh EH16 4SB, UK; Patrick Wild Centre, University of Edinburgh, Edinburgh EH8 9XD, UK; Centre for Cognitive and Neural Systems, University of Edinburgh, Edinburgh EH8 9JZ, UK
| | - Alex von Kriegsheim
- Edinburgh Cancer Research UK Centre, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh EH4 2XU, UK; Systems Biology Ireland, University College Dublin, Dublin, Ireland
| | - Fowzan S Alkuraya
- Department of Genetics, King Faisal Specialist Hospital and Research Center, Riyadh 11211, Saudi Arabia; Department of Anatomy and Cell Biology, College of Medicine, Alfaisal University, Riyadh 11533, Saudi Arabia; Saudi Human Genome Program, King Abdulaziz City for Science and Technology, Riyadh 11442, Saudi Arabia
| | - C Geoffrey Woods
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge CB2 OXY, UK; Department of Medical Genetics, University of Cambridge, and Cambridge NIHR Biomedical Research Centre, Cambridge Biomedical Campus, Cambridge CB2 OXY, UK
| | - Eamonn R Maher
- Department of Medical Genetics, University of Cambridge, and Cambridge NIHR Biomedical Research Centre, Cambridge Biomedical Campus, Cambridge CB2 OXY, UK.
| | - Pleasantine Mill
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh EH4 2XU, UK.
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9
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Keighren MA, Flockhart JH, West JD. Survival of glucose phosphate isomerase null somatic cells and germ cells in adult mouse chimaeras. Biol Open 2016; 5:596-610. [PMID: 27103217 PMCID: PMC4874354 DOI: 10.1242/bio.017111] [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] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Accepted: 03/22/2016] [Indexed: 01/22/2023] Open
Abstract
The mouse Gpi1 gene encodes the glycolytic enzyme glucose phosphate isomerase. Homozygous Gpi1(-/-) null mouse embryos die but a previous study showed that some homozygous Gpi1(-/-) null cells survived when combined with wild-type cells in fetal chimaeras. One adult female Gpi1(-/-)↔Gpi1(c/c) chimaera with functional Gpi1(-/-) null oocytes was also identified in a preliminary study. The aims were to characterise the survival of Gpi1(-/-) null cells in adult Gpi1(-/-)↔Gpi1(c/c) chimaeras and determine if Gpi1(-/-) null germ cells are functional. Analysis of adult Gpi1(-/-)↔Gpi1(c/c) chimaeras with pigment and a reiterated transgenic lineage marker showed that low numbers of homozygous Gpi1(-/-) null cells could survive in many tissues of adult chimaeras, including oocytes. Breeding experiments confirmed that Gpi1(-/-) null oocytes in one female Gpi1(-/-)↔Gpi1(c/c) chimaera were functional and provided preliminary evidence that one male putative Gpi1(-/-)↔Gpi1(c/c) chimaera produced functional spermatozoa from homozygous Gpi1(-/-) null germ cells. Although the male chimaera was almost certainly Gpi1(-/-)↔Gpi1(c/c), this part of the study is considered preliminary because only blood was typed for GPI. Gpi1(-/-) null germ cells should survive in a chimaeric testis if they are supported by wild-type Sertoli cells. It is also feasible that spermatozoa could bypass a block at GPI, but not blocks at some later steps in glycolysis, by using fructose, rather than glucose, as the substrate for glycolysis. Although chimaera analysis proved inefficient for studying the fate of Gpi1(-/-) null germ cells, it successfully identified functional Gpi1(-/-) null oocytes and revealed that some Gpi1(-/-) null cells could survive in many adult tissues.
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Affiliation(s)
- Margaret A Keighren
- Genes and Development Group, Centre for Integrative Physiology, Clinical Sciences, University of Edinburgh Medical School, Hugh Robson Building, George Square, Edinburgh EH8 9XD, UK
| | - Jean H Flockhart
- Genes and Development Group, Centre for Integrative Physiology, Clinical Sciences, University of Edinburgh Medical School, Hugh Robson Building, George Square, Edinburgh EH8 9XD, UK
| | - John D West
- Genes and Development Group, Centre for Integrative Physiology, Clinical Sciences, University of Edinburgh Medical School, Hugh Robson Building, George Square, Edinburgh EH8 9XD, UK
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10
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Hodson BA, Unbekandt M, Keighren MA, Springbett A, West JD. Evaluation of methods for one-dimensional spatial analysis of two-dimensional patterns in mouse chimaeras. J Anat 2011; 219:418-37. [PMID: 21615733 PMCID: PMC3171778 DOI: 10.1111/j.1469-7580.2011.01395.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/21/2011] [Indexed: 11/29/2022] Open
Abstract
The relative extent of cell mixing in tissues of mouse chimaeras or mosaics can be studied by comparing the distributions of the two cell populations in the tissues. However, the mean patch size is misleading because it is affected by both the extent of cell mixing and the relative contributions of the two cell populations. Previous work suggested that effects attributable to differences in tissue composition among chimaeras can be factored out either by correcting the mean patch size or by using the median patch size for the minority cell population and restricting the analysis to grossly unbalanced chimaeras. In the present study, computer simulations of two-dimensional mosaic arrays of black and white squares (representing cells) were used to simulate chimaeric tissues. Random arrays simulated tissues with extensive cell mixing, arrays of cell clumps (representing coherent clones) simulated less mixed tissues, and striped arrays simulated tissues with elongated but fragmented descendent clones. The computer simulations predicted that (i) the median patch length (minority cell population) and the corrected mean patch length would both distinguish between random and clumped patterns and (ii) differences in the variation of the composition of two perpendicular series of one-dimensional transects would distinguished between stripes and randomly orientated patches. Both predictions were confirmed by analysis of histological sections of the retinal pigment epithelium from fetal and adult mouse chimaeras. This study demonstrates that two types of non-random two-dimensional variegated patterns (clumps and stripes) can be identified in chimaeras without two-dimensional reconstruction of serial sections.
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Affiliation(s)
- Benjamin A Hodson
- Division of Reproductive and Developmental Sciences, Genes and Development Group, University of Edinburgh, George Square, Edinburgh, UK
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11
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Everett CA, Keighren MA, Flockhart JH, West JD. Evaluation of triploid<-->diploid and trisomy-3<-->diploid mouse chimeras as models for investigating how lineage restriction occurs in confined placental mosaicism. Reproduction 2008; 134:799-809. [PMID: 18042637 PMCID: PMC2756007 DOI: 10.1530/rep-07-0285] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Human confined placental mosaicism (CPM), where the placental trophoblast is mosaic for a chromosome abnormality but the fetus is chromosomally normal, can cause problems for prenatal diagnosis, but its causes are poorly understood. Tetraploid↔diploid chimeras provide a model for the development of one type of CPM, but animal models for other types of restricted mosaicism are needed. The objective of the present study was to evaluate triploid↔diploid and trisomy-3↔diploid chimeric mouse conceptuses as new models for investigating the development of restricted mosaicism. Novel stocks of mice were generated to produce triploid and trisomy-3 embryos that could be identified by DNA in situ hybridisation to a chromosome 3 transgenic marker. Triploid↔diploid and trisomy-3↔diploid mouse chimeras were produced by embryo aggregation, and the contribution of triploid or trisomy-3 cells was analysed in the fetus and extraembryonic tissues. Only two trisomy-3↔diploid chimeras were analysed but trisomy-3 cells contributed well to all lineages, so these chimeras did not show restricted mosaicism. In contrast, triploid cells usually contributed poorly to all lineages in the ten 3n↔2n chimeras analysed. They contributed more to the primitive endoderm derivatives than other lineages and were present in the primitive endoderm derivatives of all ten chimeras, but excluded from fetuses and trophectoderm derivatives in some cases. This pattern of restricted mosaicism differs from that reported for tetraploid cells in tetraploid↔diploid chimeras, and triploid↔diploid chimeras may provide a useful model for the development of some types of restricted mosaicism in human conceptuses.
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Affiliation(s)
- Clare A Everett
- Genes and Development Group, Division of Reproductive and Developmental Sciences, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh EH8 9XD, Scotland, UK
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12
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MacKay GE, Keighren MA, Wilson L, Pratt T, Flockhart JH, Mason JO, Price DJ, West JD. Evaluation of the mouse TgTP6.3 tauGFP transgene as a lineage marker in chimeras. J Anat 2005; 206:79-92. [PMID: 15679873 PMCID: PMC1571452 DOI: 10.1111/j.0021-8782.2005.00370.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [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] [Accepted: 11/25/2004] [Indexed: 11/28/2022] Open
Abstract
The mouse TgTP6.3 transgene, encoding a tauGFP fusion protein, is becoming widely used but has yet to be fully characterized and evaluated as suitable lineage marker. The aim of the present study was to investigate the phenotype of TgTP6.3(+/+) homozygotes and TgTP6.3(+/-) hemizygotes, characterize the expression of the TgTP6.3 transgene in different tissues and critically evaluate its use as a lineage marker. TgTP6.3(+/+) homozygotes died between embryonic day 14.5 and weaning, whereas TgTP6.3(+/-) hemizygotes were mostly viable and fertile but smaller than non-transgenic siblings. TgTP6.3 expression began in the late two-cell stage, persisted in most fetal and adult tissues and was uniformly expressed in many (but not all) tissues. TgTP6.3(+/-) cells were readily identified in many chimeric tissues and their contribution appeared to be quantitatively and spatially normal. Overall, tauGFP expression in hemizygous TgTP6.3(+/-) cells fulfils the main criteria of a good lineage marker for many tissues. It provides a useful lineage marker, which should be particularly suitable for axons, blood vessels and pre-implantation embryos.
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Affiliation(s)
- Gillian E MacKay
- Division of Reproductive and Developmental Sciences, University of Edinburgh, UK
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Abstract
Cell ploidy in the ovarian follicle and corpus luteum was investigated by DNA in situ hybridization to a reiterated, chromosome 3 transgene in mice that were hemizygous for the transgene. This approach was first validated by analysis of mouse kidney, pancreas and liver control tissues, which contain different frequencies of polyploid nuclei. Polyploid nuclei (with multiple hybridization signals) were seen in histological sections of both ovarian follicles and corpora lutea. The frequency of polyploid nuclei in follicles showed no consistent relationship with age (between 6 weeks and 10 months) but polyploid nuclei were significantly more abundant in corpora lutea than follicles (6.3% vs. 2.5%). This implies that production of polyploid cells is more closely associated with differentiation of ovarian follicles into corpora lutea than with the age of the female. Polyploidy tended to be more frequent in corpora lutea of mice that had mated even if they did not become pregnant. This study has highlighted the presence of polyploid cells in the mouse ovarian follicle and corpus luteum and has identified mating as a possible trigger for polyploidy in the corpus luteum. Further work is required to determine the physiological role of polyploid ovarian cells in reproduction.
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Affiliation(s)
- Margaret A Keighren
- Genes and Development Group, Division of Reproductive and Developmental Sciences, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, UK
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Collinson JM, Morris L, Reid AI, Ramaesh T, Keighren MA, Flockhart JH, Hill RE, Tan SS, Ramaesh K, Dhillon B, West JD. Clonal analysis of patterns of growth, stem cell activity, and cell movement during the development and maintenance of the murine corneal epithelium. Dev Dyn 2002; 224:432-40. [PMID: 12203735 DOI: 10.1002/dvdy.10124] [Citation(s) in RCA: 111] [Impact Index Per Article: 5.0] [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: 11/08/2022] Open
Abstract
Patterns of growth and cell movement in the developing and adult corneal epithelium were investigated by analysing clonal patches of LacZ-expressing cells in chimeric and X-inactivation mosaic mice. It was found that cell proliferation throughout the basal corneal epithelium during embryogenesis and early postnatal life creates a disordered mosaic pattern of LacZ(+) clones that contrasts with patterns of proliferation and striping produced during the later embryonic stages of retinal pigmented epithelium development. The early mosaic pattern in the corneal epithelium is replaced in the first 12 postnatal weeks by an ordered pattern of radial stripes or sectors that reflects migration without mixing of the progeny of clones of limbal stem cells. In contrast to previous assumptions, it was found that maturation of the activity of limbal stem cells and the pattern of migration of their progeny are delayed for several weeks postnatally. No evidence was found for immigration of the progeny of stem cells until the 5th postnatal week. There are approximately 100 clones of limbal stem cells initially, and clones are lost during postnatal life. Our studies provide a new assay for limbal and corneal defects in mutant mice.
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Affiliation(s)
- J Martin Collinson
- Department of Reproductive and Developmental Sciences, Genes and Development Group, University of Edinburgh, Edinburgh, Scotland, United Kingdom
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15
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Borthwick DW, West JD, Keighren MA, Flockhart JH, Innes BA, Dorin JR. Murine submucosal glands are clonally derived and show a cystic fibrosis gene-dependent distribution pattern. Am J Respir Cell Mol Biol 1999; 20:1181-9. [PMID: 10340937 DOI: 10.1165/ajrcmb.20.6.3475] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.0] [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: 11/24/2022] Open
Abstract
Submucosal glands (SMGs) are the major site of expression of the cystic fibrosis (CF) transmembrane conductance regulator gene (CFTR) in the human lung. As such, SMGs may be a critical component of CF lung disease pathogenesis and an important target for gene therapy. Gene-targeted mouse models exist for CF and these are used to validate gene therapy or other interventions and to dissect CF phenotypes. It is important, therefore, to compare human and mouse SMGs. We show that SMGs in the mouse are similar in structure, cell types, and Cftr expression to those in the human. Murine SMGs were found to be present in the proximal regions of the trachea at the same density as in humans but, unlike in humans, did not extend below the trachea. Upon investigation of homozygous Cftr tm1HGU and Cftr tm1G551D mutant mice, SMGs were found to extend more distally than those in wild-type control mice (P < 0.05). To investigate the development of SMGs we generated aggregation chimeric mice. Chimeric offspring contained a contribution of transgenic cells that were detectable either by DNA in situ hybridization (reiterated beta-globin transgene TgN[Hbb-bl]83Clo) or beta-galactosidase histochemistry (Lac Z reporter gene TgR[ROSA26]- 26Sor). Analysis of the distribution of transgenic cells in chimeric SMGs suggests that SMGs are clonally derived.
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Affiliation(s)
- D W Borthwick
- MRC Human Genetics Unit, University of Edinburgh, Centre for Reproductive Biology, Edinburgh, United Kingdom
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16
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Abstract
The spatial distribution of cells in chimaeric tissues, composed of two genotypes, provides insights into the extent of cell mixing during development and growth. However, direct measurement of patch sizes is not usually meaningful because, when the proportion of one genotype is high, a single patch may encompass several adjacent coherent clones of like genotype (clone aggregation). Two previously used methods of comparing patch lengths were evaluated to overcome this problem. The corrected mean patch length (corrected for the predicted effects of random clone aggregation) is a more useful summary statistic than the median patch length of the minor genotype, because its use is not restricted to grossly unbalanced chimaeras, but its validity has been questioned. The two methods gave almost identical numerical summaries of patch sizes in the retinal pigment epithelium of fetal chimaeras, thereby validating the use of the corrected mean patch length for this tissue. The present study also showed that the corrected patch length was unaffected by the presence of cells hemizygous for the TgN(Hbb-b1)83Clo transgene and that the proportion of pigmented cells in a single histological section was representative of the overall composition of the chimaeric fetus.
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Affiliation(s)
- J D West
- Department of Obstetrics and Gynaecology, University of Edinburgh, UK
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17
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Abstract
The mouse transgene, provisionally designated TgN(Hbb-b1)83Clo, was produced by Dr C. Lo by pronuclear injection of the cloned beta-major globin gene and comprises a highly reiterated sequence that is readily detected by DNA in situ hybridization on histological sections. This fulfils many of the requirements of an ideal genetic cell marker and has been widely used for lineage studies with mouse chimaeras. However, it is not known whether it causes cell selection or influences developmental processes, such as cell mixing, in chimaeric tissues. In the present study, non-transgenic genetic markers (electrophoretic polymorphisms of glucose phosphate isomerase and differences in eye pigmentation) revealed no significant effect of the presence of hemizygous transgenic cells on the overall composition, size or gross morphology of 12 1/2 d chimaeric foetuses, placentas or extraembryonic membranes. Also, a previously described maternal genetic effect on the composition of chimaeric tissues occurred in the presence or absence of the transgene. These tests have demonstrated that hemizygous cells are not at a significant selective disadvantage, when incorporated into mouse aggregation chimaeras with non-transgenic cells. Further studies are needed to test whether homozygous transgenic cells are also selectively neutral and to test whether hemizygous or homozygous transgenic cells influence developmental processes, such as cell mixing, that were not tested.
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Affiliation(s)
- J D West
- Department of Obstetrics and Gynaecology, University of Edinburgh, UK
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Kinnaird JH, Keighren MA, Kinsey JA, Eaton M, Fincham JR. Cloning of the am (glutamate dehydrogenase) gene of Neurospora crassa through the use of a synthetic DNA probe. Gene X 1982; 20:387-96. [PMID: 6299898 DOI: 10.1016/0378-1119(82)90207-4] [Citation(s) in RCA: 99] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
In a previous study the alteration in the amino acid sequence of Neurospora crassa NADP-specific glutamate dehydrogenase (GDH) resulting from two mutually compensating frameshift mutations was used to deduce the first 17 nucleotides of the coding sequence of the am gene. In the work reported here, a synthetic 17-mer corresponding to the deduced sequence was shown to hybridize strongly to a 9-kb HindIII fragment from N. crassa wild-type DNA but not to any corresponding fragment from the DNA of a mutant strain known to be deleted for most or all of the gene. Wild-type HindIII fragments were fractionated for size and a fraction centering around 9 kb was cloned in vector lambda L47. Two clones carrying the strongly hybridizing fragment were identified. The hybridization to the 17-mer was localized within a 2.7-kb BamHI fragment and, within this, to a 700-bp BamHI-Bg/II subfragment. 5' end-labelled polyadenylated RNA isolated from wild-type mycelium hybridized to the 2.7-kb BamHI fragment and not appreciably to flanking fragments. The partial sequence analysis of the BamHI-Bg/II fragment has confirmed that the 17-mer probe matches the coding sequence at the 5' end of the gene and has also revealed an intervening sequence 67 bp in length, interrupting codon 15. Both the 9-kb HindIII fragment and the 2.7-kb BamHI fragment have been shown to be capable of transforming the deletion mutant to prototrophy and ability to produce GDH. Analysis of one transformant showed that the am gene was integrated, together with a part of the long arm of the lambda vector, at an unusual locus. This transformant, in which the am gene does not show its normal linkage to the linkage group 5 marker inl, was found to produce GDH to about 20% of the normal level.
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Keighren MA, Price NC. A study of the role of the reactive thiol group of rabbit muscle creatine kinase with a chromophoric reporter group. Biochem J 1978; 171:269-72. [PMID: 646820 PMCID: PMC1184157 DOI: 10.1042/bj1710269] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Substrate- and ligand-induced conformational changes were studied in a series of thiol-modified derivatives of rabbit muscle creatine kinase that retained different amounts of enzymic activity. The results indicate that the 'reactive' thiol group of the enzyme is required for the conformational changes associated with formation of a 'transition-state analogue' complex.
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