1
|
Kaiyrzhanov R, Rad A, Lin SJ, Bertoli-Avella A, Kallemeijn WW, Godwin A, Zaki MS, Huang K, Lau T, Petree C, Efthymiou S, Karimiani EG, Hempel M, Normand EA, Rudnik-Schöneborn S, Schatz UA, Baggelaar MP, Ilyas M, Sultan T, Alvi JR, Ganieva M, Fowler B, Aanicai R, Tayfun GA, Al Saman A, Alswaid A, Amiri N, Asilova N, Shotelersuk V, Yeetong P, Azam M, Babaei M, Monajemi GB, Mohammadi P, Samie S, Banu SH, Pinto Basto J, Kortüm F, Bauer M, Bauer P, Beetz C, Garshasbi M, Issa AH, Eyaid W, Ahmed H, Hashemi N, Hassanpour K, Herman I, Ibrohimov S, Abdul-Majeed BA, Imdad M, Isrofilov M, Kaiyal Q, Khan S, Kirmse B, Koster J, Lourenço CM, Mitani T, Moldovan O, Murphy D, Najafi M, Pehlivan D, Rocha ME, Salpietro V, Schmidts M, Shalata A, Mahroum M, Talbeya JK, Taylor RW, Vazquez D, Vetro A, Waterham HR, Zaman M, Schrader TA, Chung WK, Guerrini R, Lupski JR, Gleeson J, Suri M, Jamshidi Y, Bhatia KP, Vona B, Schrader M, Severino M, Guille M, Tate EW, Varshney GK, Houlden H, Maroofian R. Bi-allelic ACBD6 variants lead to a neurodevelopmental syndrome with progressive and complex movement disorders. Brain 2024; 147:1436-1456. [PMID: 37951597 PMCID: PMC10994533 DOI: 10.1093/brain/awad380] [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: 05/18/2022] [Revised: 09/13/2023] [Accepted: 10/20/2023] [Indexed: 11/14/2023] Open
Abstract
The acyl-CoA-binding domain-containing protein 6 (ACBD6) is ubiquitously expressed, plays a role in the acylation of lipids and proteins and regulates the N-myristoylation of proteins via N-myristoyltransferase enzymes (NMTs). However, its precise function in cells is still unclear, as is the consequence of ACBD6 defects on human pathophysiology. Using exome sequencing and extensive international data sharing efforts, we identified 45 affected individuals from 28 unrelated families (consanguinity 93%) with bi-allelic pathogenic, predominantly loss-of-function (18/20) variants in ACBD6. We generated zebrafish and Xenopus tropicalis acbd6 knockouts by CRISPR/Cas9 and characterized the role of ACBD6 on protein N-myristoylation with myristic acid alkyne (YnMyr) chemical proteomics in the model organisms and human cells, with the latter also being subjected further to ACBD6 peroxisomal localization studies. The affected individuals (23 males and 22 females), aged 1-50 years, typically present with a complex and progressive disease involving moderate-to-severe global developmental delay/intellectual disability (100%) with significant expressive language impairment (98%), movement disorders (97%), facial dysmorphism (95%) and mild cerebellar ataxia (85%) associated with gait impairment (94%), limb spasticity/hypertonia (76%), oculomotor (71%) and behavioural abnormalities (65%), overweight (59%), microcephaly (39%) and epilepsy (33%). The most conspicuous and common movement disorder was dystonia (94%), frequently leading to early-onset progressive postural deformities (97%), limb dystonia (55%) and cervical dystonia (31%). A jerky tremor in the upper limbs (63%), a mild head tremor (59%), parkinsonism/hypokinesia developing with advancing age (32%) and simple motor and vocal tics were among other frequent movement disorders. Midline brain malformations including corpus callosum abnormalities (70%), hypoplasia/agenesis of the anterior commissure (66%), short midbrain and small inferior cerebellar vermis (38% each) as well as hypertrophy of the clava (24%) were common neuroimaging findings. Acbd6-deficient zebrafish and Xenopus models effectively recapitulated many clinical phenotypes reported in patients including movement disorders, progressive neuromotor impairment, seizures, microcephaly, craniofacial dysmorphism and midbrain defects accompanied by developmental delay with increased mortality over time. Unlike ACBD5, ACBD6 did not show a peroxisomal localization and ACBD6-deficiency was not associated with altered peroxisomal parameters in patient fibroblasts. Significant differences in YnMyr-labelling were observed for 68 co- and 18 post-translationally N-myristoylated proteins in patient-derived fibroblasts. N-myristoylation was similarly affected in acbd6-deficient zebrafish and X. tropicalis models, including Fus, Marcks and Chchd-related proteins implicated in neurological diseases. The present study provides evidence that bi-allelic pathogenic variants in ACBD6 lead to a distinct neurodevelopmental syndrome accompanied by complex and progressive cognitive and movement disorders.
Collapse
Affiliation(s)
- Rauan Kaiyrzhanov
- Department of Neuromuscular Diseases, UCL Institute of Neurology, London WC1N 3BG, UK
| | - Aboulfazl Rad
- Cellular and Molecular Research Center, Sabzevar University of Medical Sciences, Sabzevar 009851, Iran
- Tübingen Hearing Research Centre, Department of Otolaryngology, Head and Neck Surgery, Eberhard Karls University, 72076 Tübingen, Germany
| | - Sheng-Jia Lin
- Genes & Human Disease Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK 73104, USA
| | | | - Wouter W Kallemeijn
- Department of Chemistry, Imperial College London, Molecular Sciences Research Hub, London W12 0BZ, UK
- Chemical Biology and Therapeutic Discovery Lab, The Francis Crick Institute, London NW1 1AT, UK
| | - Annie Godwin
- European Xenopus Resource Centre—XenMD, School of Biological Sciences, University of Portsmouth, Portsmouth PO1 2DT, UK
| | - Maha S Zaki
- Clinical Genetics Department, Human Genetics and Genome Research Institute, National Research Centre, 12622 Cairo, Egypt
| | - Kevin Huang
- Genes & Human Disease Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK 73104, USA
| | - Tracy Lau
- Department of Neuromuscular Diseases, UCL Institute of Neurology, London WC1N 3BG, UK
| | - Cassidy Petree
- Genes & Human Disease Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK 73104, USA
| | - Stephanie Efthymiou
- Department of Neuromuscular Diseases, UCL Institute of Neurology, London WC1N 3BG, UK
| | - Ehsan Ghayoor Karimiani
- Genetics Research Centre, Molecular and Clinical Sciences Institute, St George’s University of London, London SW17 0RE, UK
- Department of Medical Genetics, Next Generation Genetic Polyclinic, Mashhad 1696700, Iran
| | - Maja Hempel
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
- Institute of Human Genetics, University Hospital Heidelberg, Heidelberg 69120, Germany
| | | | | | - Ulrich A Schatz
- Institute of Human Genetics, Medical University Innsbruck, Innsbruck 6020, Austria
- Institute of Human Genetics, Technical University of Munich, Munich, 81675, Germany
| | - Marc P Baggelaar
- Department of Chemistry, Imperial College London, Molecular Sciences Research Hub, London W12 0BZ, UK
- Biomolecular Mass Spectrometry & Proteomics Group, Utrecht University, 3584 CH Utrecht, The Netherlands
| | - Muhammad Ilyas
- Department of BioEngineering, University of Engineering and Applied Sciences, 19130 Swat, Pakistan
- Centre for Omic Sciences, Islamia College University, 25000 Peshawar, Pakistan
| | - Tipu Sultan
- Department of Pediatric Neurology, Institute of Child Health, Children Hospital, Lahore 54600, Pakistan
| | - Javeria Raza Alvi
- Department of Pediatric Neurology, Institute of Child Health, Children Hospital, Lahore 54600, Pakistan
| | - Manizha Ganieva
- Department of Neurology, Avicenna Tajik State Medical University, 734063 Dushanbe, Tajikistan
| | - Ben Fowler
- Imaging Core, Oklahoma Medical Research Foundation, Oklahoma City, OK 73104, USA
| | - Ruxandra Aanicai
- Department of Medical Genetics, CENTOGENE GmbH, 18055 Rostock, Germany
| | - Gulsen Akay Tayfun
- Department of Pediatric Genetics, Marmara University Medical School, 34722 Istanbul, Turkey
| | - Abdulaziz Al Saman
- Pediatric Neurology Department, National Neuroscience Institute, King Fahad Medical City, 49046 Riyadh, Saudi Arabia
| | - Abdulrahman Alswaid
- King Saud Bin Abdulaziz University for Health Sciences, Department of Pediatrics, King Abdullah Specialized Children’s Hospital, Riyadh 11461, Saudi Arabia
| | - Nafise Amiri
- International Collaboration on Repair Discoveries (ICORD), University of British Columbia, Vancouver, BC V5Z 1M9, Canada
| | - Nilufar Asilova
- Department of Neurology, Avicenna Tajik State Medical University, 734063 Dushanbe, Tajikistan
| | - Vorasuk Shotelersuk
- Center of Excellence for Medical Genomics, Department of Pediatrics, King Chulalongkorn Memorial Hospital, Faculty of Medicine, Chulalongkorn University, Bangkok 10330, Thailand
| | - Patra Yeetong
- Division of Human Genetics, Department of Botany, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand
| | - Matloob Azam
- Pediatrics and Child Neurology, Wah Medical College, 47000 Wah Cantt, Pakistan
| | - Meisam Babaei
- Department of Pediatrics, North Khorasan University of Medical Sciences, Bojnurd 94149-74877, Iran
| | | | - Pouria Mohammadi
- Children’s Medical Center, Pediatrics Center of Excellence, Ataxia Clinic, Tehran University of Medical Sciences, Tehran 1416634793, Iran
- Faculty of Medical Sciences, Department of Medical Genetics, Tarbiat Modares University, Tehran 1411944961, Iran
| | - Saeed Samie
- Pars Advanced and Minimally Invasive Medical Manners Research Center, Pars Hospital, Tehran, Iran
| | - Selina Husna Banu
- Department of Paediatric Neurology and Development, Dr. M.R. Khan Shishu (Children) Hospital and Institute of Child Health, Dhaka 1216, Bangladesh
| | - Jorge Pinto Basto
- Department of Medical Genetics, CENTOGENE GmbH, 18055 Rostock, Germany
| | - Fanny Kortüm
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, 20246 Hamburg, Germany
| | - Mislen Bauer
- Division of Clinical Genetics and Metabolism, Nicklas Children's Hospital, Miami, FL 33155, USA
| | - Peter Bauer
- Department of Medical Genetics, CENTOGENE GmbH, 18055 Rostock, Germany
| | - Christian Beetz
- Department of Medical Genetics, CENTOGENE GmbH, 18055 Rostock, Germany
| | - Masoud Garshasbi
- Faculty of Medical Sciences, Department of Medical Genetics, Tarbiat Modares University, Tehran 1411944961, Iran
| | | | - Wafaa Eyaid
- Department of Genetics and Precision Medicine, King Abdullah International Medical Research Centre, King Saud bin Abdulaziz University for Health Science, King Abdulaziz Medical City, Ministry of National Guard-Health Affairs (NGHA), Riyadh 11426, Saudi Arabia
| | - Hind Ahmed
- Department of Genetics and Precision Medicine, King Abdullah International Medical Research Centre, King Saud bin Abdulaziz University for Health Science, King Abdulaziz Medical City, Ministry of National Guard-Health Affairs (NGHA), Riyadh 11426, Saudi Arabia
| | - Narges Hashemi
- Department of Pediatrics, School of Medicine, Mashhad University of Medical Sciences, 13131–99137 Mashhad, Iran
| | - Kazem Hassanpour
- Non-Communicable Diseases Research Center, Sabzevar University of Medical Sciences, 319 Sabzevar, Iran
| | - Isabella Herman
- Section of Pediatric Neurology and Developmental Neuroscience, Department of Pediatrics, Baylor College of Medicine, Houston, TX 68010, USA
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
- Department of Neurology, Texas Children’s Hospital, Houston, TX 77030, USA
- Pediatric Neurology, Neurogenetics and Rare Diseases, Boys Town National Research Hospital, Boys Town, NE 68131, USA
| | - Sherozjon Ibrohimov
- Department of Neurology, Avicenna Tajik State Medical University, 734063 Dushanbe, Tajikistan
| | - Ban A Abdul-Majeed
- Molecular Pathology and Genetics, The Pioneer Molecular Pathology Lab, Baghdad 10044, Iraq
| | - Maria Imdad
- Centre for Human Genetics, Hazara University, 21300 Mansehra, Pakistan
| | - Maksudjon Isrofilov
- Department of Neurology, Avicenna Tajik State Medical University, 734063 Dushanbe, Tajikistan
| | - Qassem Kaiyal
- Department of Pediatric Neurology, Clalit Health Care, 2510500 Haifa, Israel
| | - Suliman Khan
- Department of Medical Genetics, CENTOGENE GmbH, 18055 Rostock, Germany
| | - Brian Kirmse
- SOM-Peds-Genetics, University of Mississippi Medical Center, Jackson MS, 39216, USA
| | - Janet Koster
- Laboratory Genetic Metabolic Diseases, Amsterdam University Medical Centers location AMC, 1100 DD Amsterdam, The Netherlands
| | - Charles Marques Lourenço
- Faculdade de Medicina, Centro Universitario Estácio de Ribeirão Preto, 14096-160 São Paulo, Brazil
| | - Tadahiro Mitani
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Oana Moldovan
- Serviço de Genética Médica, Departamento de Pediatria, Hospital de Santa Maria, Centro Hospitalar Universitário de Lisboa Norte, 1649-035 Lisboa, Portugal
| | - David Murphy
- Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, University College London, London WC1N 3BG, UK
| | - Maryam Najafi
- Pediatrics Genetics Division, Center for Pediatrics and Adolescent Medicine, Faculty of Medicine, Freiburg University, 79106 Freiburg, Germany
- Genome Research Division, Human Genetics Department, Radboud University Medical Center, 6500 HB Nijmegen, The Netherlands
| | - Davut Pehlivan
- Section of Pediatric Neurology and Developmental Neuroscience, Department of Pediatrics, Baylor College of Medicine, Houston, TX 68010, USA
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | | | - Vincenzo Salpietro
- Department of Neuromuscular Diseases, UCL Institute of Neurology, London WC1N 3BG, UK
| | - Miriam Schmidts
- Pediatrics Genetics Division, Center for Pediatrics and Adolescent Medicine, Faculty of Medicine, Freiburg University, 79106 Freiburg, Germany
- Genome Research Division, Human Genetics Department, Radboud University Medical Center, 6500 HB Nijmegen, The Netherlands
- CIBSS-Centre for Integrative Biological Signalling Studies, University of Freiburg, Freiburg, Germany
| | - Adel Shalata
- Pediatrics and Medical Genetics, the Simon Winter Institute for Human Genetics, Bnai Zion Medical Center, 31048 Haifa, Israel
- Bruce Rappaport Faculty of Medicine, the Technion institution of Technology, 3200003 Haifa, Israel
| | - Mohammad Mahroum
- CIBSS-Centre for Integrative Biological Signalling Studies, University of Freiburg, Freiburg, Germany
| | - Jawabreh Kassem Talbeya
- Pediatrics and Medical Genetics, the Simon Winter Institute for Human Genetics, Bnai Zion Medical Center, 31048 Haifa, Israel
- Department of Radiology, The Bnai Zion Medical Center, Haifa 31048, Israel
| | - Robert W Taylor
- Wellcome Centre for Mitochondrial Research, Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
- NHS Highly Specialised Service for Rare Mitochondrial Disorders, Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne NE1 4LP, UK
| | - Dayana Vazquez
- Division of Clinical Genetics and Metabolism, Nicklas Children's Hospital, Miami, FL 33155, USA
| | - Annalisa Vetro
- Neuroscience Department, Meyer Children's Hospital IRCCS, 50139 Florence, Italy
| | - Hans R Waterham
- Laboratory Genetic Metabolic Diseases, Amsterdam University Medical Centers location AMC, 1100 DD Amsterdam, The Netherlands
| | - Mashaya Zaman
- Department of Paediatric Neurology and Development, Dr. M.R. Khan Shishu (Children) Hospital and Institute of Child Health, Dhaka 1216, Bangladesh
| | - Tina A Schrader
- Department of Biosciences, University of Exeter, Exeter EX4 4QD, UK
| | - Wendy K Chung
- Department of Pediatrics, Columbia University Irving Medical Center, New York, NY 10032, USA
- Department of Medicine, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Renzo Guerrini
- Neuroscience Department, Meyer Children's Hospital IRCCS, 50139 Florence, Italy
- Neuroscience, Pharmacology and Child Health Department, University of Florence, 50139 Florence, Italy
| | - James R Lupski
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
- Department of Neurology, Texas Children’s Hospital, Houston, TX 77030, USA
- Human Genome Sequencing Center, Baylor College of Medicine, Houston, TX 77030, USA
| | - Joseph Gleeson
- Department of Neurosciences, University of California, San Diego, CA 92093, USA
- Department of Neurosciences, Rady Children's Institute for Genomic Medicine, San Diego, CA 92025, USA
| | - Mohnish Suri
- Clinical Genetics Service, Nottingham University Hospitals NHS Trust, Nottingham NG5 1PB, UK
| | - Yalda Jamshidi
- Genetics Research Centre, Molecular and Clinical Sciences Institute, St George’s University of London, London SW17 0RE, UK
- Human Genetics Centre of Excellence, Novo Nordisk Research Centre Oxford, Oxford, OX3 7FZ, UK
| | - Kailash P Bhatia
- Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, University College London, London WC1N 3BG, UK
| | - Barbara Vona
- Tübingen Hearing Research Centre, Department of Otolaryngology, Head and Neck Surgery, Eberhard Karls University, 72076 Tübingen, Germany
- Institute of Human Genetics, University Medical Center Göttingen, 37073 Göttingen, Germany
- Institute for Auditory Neuroscience and Inner Ear Lab, University Medical Center Göttingen, 37075 Göttingen, Germany
| | - Michael Schrader
- Department of Biosciences, University of Exeter, Exeter EX4 4QD, UK
| | | | - Matthew Guille
- European Xenopus Resource Centre—XenMD, School of Biological Sciences, University of Portsmouth, Portsmouth PO1 2DT, UK
| | - Edward W Tate
- Department of Chemistry, Imperial College London, Molecular Sciences Research Hub, London W12 0BZ, UK
- Chemical Biology and Therapeutic Discovery Lab, The Francis Crick Institute, London NW1 1AT, UK
| | - Gaurav K Varshney
- Genes & Human Disease Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK 73104, USA
| | - Henry Houlden
- Department of Neuromuscular Diseases, UCL Institute of Neurology, London WC1N 3BG, UK
| | - Reza Maroofian
- Department of Neuromuscular Diseases, UCL Institute of Neurology, London WC1N 3BG, UK
| |
Collapse
|
2
|
Guille M, Grainger R. Genetics and Gene Editing Methods in Xenopus laevis and Xenopus tropicalis. Cold Spring Harb Protoc 2023; 2023:pdb.top107045. [PMID: 36283837 DOI: 10.1101/pdb.top107045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Our understanding of biological systems has for many years been heavily influenced by experimental approaches that exploit genetic methods. These include gain-of-function experiments that overexpress transgenes or ectopically express injected RNA and loss-of-function experiments that knock out genes or knock down RNAs. Here, we review how these methods have been applied in Xenopus frogs and introduce a variety of protocols for genetic manipulation of Xenopus laevis and Xenopus tropicalis.
Collapse
Affiliation(s)
- Matthew Guille
- European Xenopus Resource Centre, School of Biological Sciences, University of Portsmouth, Portsmouth PO1 2UP, United Kingdom
| | - Robert Grainger
- Department of Biology, University of Virginia, Charlottesville, Virginia 22903, USA
| |
Collapse
|
3
|
Alles N, Guille M, Górecki DC. Automated multi-sample DNA extraction for genotyping live Xenopus embryos. Dev Dyn 2023; 252:429-438. [PMID: 36217575 PMCID: PMC10953317 DOI: 10.1002/dvdy.544] [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: 05/23/2022] [Revised: 09/26/2022] [Accepted: 10/04/2022] [Indexed: 11/05/2022] Open
Abstract
BACKGROUND Xenopus frogs are used extensively for modeling genetic diseases owing to characteristics such as the abundance of eggs combined with their large size, allowing easy manipulation, and rapid external embryo development enabling the examination of cellular and phenotypic alterations throughout embryogenesis. However, genotyping of mutant animals is currently done either as part of a large group, requiring many embryos, or late in development with welfare effects. Therefore, we adapted the Zebrafish Embryonic Genotyper for rapid genomic DNA extraction from Xenopus tropicalis and Xenopus laevis at early stages. RESULTS Sufficient and good quality DNA was extracted as early as the Nieuwkoop and Faber stage 19 and, importantly, no detrimental effects of the extraction process on the subsequent tadpole development, behavior, or morphology were observed. Amplicons of up to 800 bp were successfully amplified and used for further analyses such as gel electrophoresis, T7 endonuclease I assay and Sanger sequencing. CONCLUSION This method allows rapid genotyping during the early stages of Xenopus development, which enables safe identification of mutants. These can be analyzed at early developmental stages or selected for raising without the need for invasive genotyping later, with resource savings and ethical gains in line with the 3Rs principles.
Collapse
Affiliation(s)
- Narmadha Alles
- School of Pharmacy and Biomedical SciencesUniversity of PortsmouthPortsmouthUK
| | - Matthew Guille
- School of Biological SciencesUniversity of PortsmouthPortsmouthUK
| | - Dariusz C. Górecki
- School of Pharmacy and Biomedical SciencesUniversity of PortsmouthPortsmouthUK
| |
Collapse
|
4
|
Ismail V, Zachariassen LG, Godwin A, Sahakian M, Ellard S, Stals KL, Baple E, Brown KT, Foulds N, Wheway G, Parker MO, Lyngby SM, Pedersen MG, Desir J, Bayat A, Musgaard M, Guille M, Kristensen AS, Baralle D. Identification and functional evaluation of GRIA1 missense and truncation variants in individuals with ID: An emerging neurodevelopmental syndrome. Am J Hum Genet 2022; 109:1217-1241. [PMID: 35675825 PMCID: PMC9300760 DOI: 10.1016/j.ajhg.2022.05.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [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: 12/16/2021] [Accepted: 05/11/2022] [Indexed: 12/02/2022] Open
Abstract
GRIA1 encodes the GluA1 subunit of α-amino-3-hydroxy-5-methyl-4-isoxazole propionate (AMPA) receptors, which are ligand-gated ion channels that act as excitatory receptors for the neurotransmitter L-glutamate (Glu). AMPA receptors (AMPARs) are homo- or heteromeric protein complexes with four subunits, each encoded by different genes, GRIA1 to GRIA4. Although GluA1-containing AMPARs have a crucial role in brain function, the human phenotype associated with deleterious GRIA1 sequence variants has not been established. Subjects with de novo missense and nonsense GRIA1 variants were identified through international collaboration. Detailed phenotypic and genetic assessments of the subjects were carried out and the pathogenicity of the variants was evaluated in vitro to characterize changes in AMPAR function and expression. In addition, two Xenopus gria1 CRISPR-Cas9 F0 models were established to characterize the in vivo consequences. Seven unrelated individuals with rare GRIA1 variants were identified. One individual carried a homozygous nonsense variant (p.Arg377Ter), and six had heterozygous missense variations (p.Arg345Gln, p.Ala636Thr, p.Ile627Thr, and p.Gly745Asp), of which the p.Ala636Thr variant was recurrent in three individuals. The cohort revealed subjects to have a recurrent neurodevelopmental disorder mostly affecting cognition and speech. Functional evaluation of major GluA1-containing AMPAR subtypes carrying the GRIA1 variant mutations showed that three of the four missense variants profoundly perturb receptor function. The homozygous stop-gain variant completely destroys the expression of GluA1-containing AMPARs. The Xenopus gria1 models show transient motor deficits, an intermittent seizure phenotype, and a significant impairment to working memory in mutants. These data support a developmental disorder caused by both heterozygous and homozygous variants in GRIA1 affecting AMPAR function.
Collapse
Affiliation(s)
- Vardha Ismail
- Wessex Clinical Genetics Service, Princess Anne Hospital, University Hospital Southampton NHS Foundation Trust, Coxford Rd, Southampton SO165YA, UK
| | - Linda G Zachariassen
- Department of Drug Design and Pharmacology, University of Copenhagen, Universitetsparken 2, 2100 Copenhagen, Denmark
| | - Annie Godwin
- European Xenopus Resource Centre, School of Biological Sciences, King Henry Building, King Henry I Street, Portsmouth PO1 2DY, UK
| | - Mane Sahakian
- Department of Drug Design and Pharmacology, University of Copenhagen, Universitetsparken 2, 2100 Copenhagen, Denmark
| | - Sian Ellard
- Exeter Genomics Laboratory, Royal Devon & Exeter NHS Foundation Trust, Barrack Road, Exeter EX2 5DW, UK; University of Exeter Medical School, Royal Devon & Exeter NHS Foundation Trust, Barrack Road, Exeter EX2 5DW, UK
| | - Karen L Stals
- Exeter Genomics Laboratory, Royal Devon & Exeter NHS Foundation Trust, Barrack Road, Exeter EX2 5DW, UK
| | - Emma Baple
- Exeter Genomics Laboratory, Royal Devon & Exeter NHS Foundation Trust, Barrack Road, Exeter EX2 5DW, UK; University of Exeter Medical School, Royal Devon & Exeter NHS Foundation Trust, Barrack Road, Exeter EX2 5DW, UK
| | - Kate Tatton Brown
- South-West Thames Clinical Genetics Service, St George's University of London, Cranmer Terrace, London SW17 0RE, UK
| | - Nicola Foulds
- Wessex Clinical Genetics Service, Princess Anne Hospital, University Hospital Southampton NHS Foundation Trust, Coxford Rd, Southampton SO165YA, UK
| | - Gabrielle Wheway
- Faculty of Medicine, University of Southampton, Duthie Building, Southampton General Hospital, Tremona Road, Southampton SO16 6YD, UK
| | - Matthew O Parker
- School of Pharmacy and Biomedical Sciences, University of Portsmouth, Old St Michael's Building, White Swan Road, Portsmouth PO1 2DT, UK
| | - Signe M Lyngby
- Department of Drug Design and Pharmacology, University of Copenhagen, Universitetsparken 2, 2100 Copenhagen, Denmark
| | - Miriam G Pedersen
- Department of Drug Design and Pharmacology, University of Copenhagen, Universitetsparken 2, 2100 Copenhagen, Denmark
| | - Julie Desir
- Département de Génétique Clinique - Institut de Pathologie et de Génétique, Institut de Pathologie et de Génétique, Avenue Georges Lemaître, 25 6041 Gosselies, Belgium
| | - Allan Bayat
- Danish Epilepsy Centre, Department of Epilepsy Genetics and Personalized Medicine, 4293 Dianalund, Denmark; Department of Regional Health Research, University of Southern Denmark, 5230 Odense, Denmark
| | - Maria Musgaard
- Department of Chemistry and Biomolecular Sciences, University of Ottawa, 75 Laurier Ave E, Ottawa, ON K1N 6N5, Canada
| | - Matthew Guille
- European Xenopus Resource Centre, School of Biological Sciences, King Henry Building, King Henry I Street, Portsmouth PO1 2DY, UK
| | - Anders S Kristensen
- Department of Drug Design and Pharmacology, University of Copenhagen, Universitetsparken 2, 2100 Copenhagen, Denmark.
| | - Diana Baralle
- Wessex Clinical Genetics Service, Princess Anne Hospital, University Hospital Southampton NHS Foundation Trust, Coxford Rd, Southampton SO165YA, UK; Faculty of Medicine, University of Southampton, Duthie Building, Southampton General Hospital, Tremona Road, Southampton SO16 6YD, UK.
| |
Collapse
|
5
|
Willsey HR, Guille M, Grainger RM. Modeling Human Genetic Disorders with CRISPR Technologies in Xenopus. Cold Spring Harb Protoc 2022; 2022:pdb.prot106997. [PMID: 34531330 DOI: 10.1101/pdb.prot106997] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Combining the power of Xenopus developmental biology with CRISPR-based technologies promises great discoveries in understanding and treating human genetic disorders. Here we provide a practical pipeline for how to go from known disease gene(s) or risk gene(s) of interest to methods for gaining functional insight into the contribution of these genes to disorder etiology in humans.
Collapse
Affiliation(s)
- Helen Rankin Willsey
- Department of Psychiatry and Behavioral Sciences, Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, California 94143, USA;
| | - Matthew Guille
- European Xenopus Resource Centre, School of Biological Sciences, University of Portsmouth, Portsmouth PO1 2UP, United Kingdom
| | - Robert M Grainger
- Department of Biology, University of Virginia, Charlottesville, Virginia 22904, USA
| |
Collapse
|
6
|
Tuncay A, Noble A, Guille M, Cobley JN. RedoxiFluor: A microplate technique to quantify target-specific protein thiol redox state in relative percentage and molar terms. Free Radic Biol Med 2022; 181:118-129. [PMID: 35131446 PMCID: PMC8904371 DOI: 10.1016/j.freeradbiomed.2022.01.023] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Revised: 01/12/2022] [Accepted: 01/23/2022] [Indexed: 12/12/2022]
Abstract
Unravelling how reactive oxygen species regulate fundamental biological processes is hampered by the lack of an accessible microplate technique to quantify target-specific protein thiol redox state in percentages and moles. To meet this unmet need, we present RedoxiFluor. RedoxiFluor uses two spectrally distinct thiol-reactive fluorescent conjugated reporters, a capture antibody, detector antibody and a standard curve to quantify target-specific protein thiol redox state in relative percentage and molar terms. RedoxiFluor can operate in global mode to assess the redox state of the bulk thiol proteome and can simultaneously assess the redox state of multiple targets in array mode. Extensive proof-of-principle experiments robustly validate the assay principle and the value of each RedoxiFluor mode in diverse biological contexts. In particular, array mode RedoxiFluor shows that the response of redox-regulated phosphatases to lipopolysaccharide (LPS) differs in human monocytes. Specifically, LPS increased PP2A-, SHP1-, PTP1B-, and CD45-specific reversible thiol oxidation without changing the redox state of calcineurin, PTEN, and SHP2. The relative percentage and molar terms are interpretationally useful and define the most complete and extensive microplate redox analysis achieved to date. RedoxiFluor is a new antibody technology with the power to quantify relative target-specific protein thiol redox state in percentages and moles relative to the bulk thiol proteome and selected other targets in a widely accessible, simple and easily implementable microplate format.
Collapse
Affiliation(s)
- Ahmet Tuncay
- Redox Biology Group, UHI, Inverness, IV2 3JH, UK
| | - Anna Noble
- European Xenopus Resource Centre, University of Portsmouth, Portsmouth, PO1 2DY, UK
| | - Matthew Guille
- European Xenopus Resource Centre, University of Portsmouth, Portsmouth, PO1 2DY, UK
| | | |
Collapse
|
7
|
Godden AM, Antonaci M, Ward NJ, van der Lee M, Abu-Daya A, Guille M, Wheeler GN. An efficient miRNA knockout approach using CRISPR-Cas9 in Xenopus. Dev Biol 2022; 483:66-75. [PMID: 34968443 PMCID: PMC8865746 DOI: 10.1016/j.ydbio.2021.12.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Revised: 12/15/2021] [Accepted: 12/23/2021] [Indexed: 12/14/2022]
Abstract
In recent years CRISPR-Cas9 knockouts (KO) have become increasingly ultilised to study gene function. MicroRNAs (miRNAs) are short non-coding RNAs, 20-22 nucleotides long, which affect gene expression through post-transcriptional repression. We previously identified miRNAs-196a and -219 as implicated in the development of Xenopus neural crest (NC). The NC is a multipotent stem-cell population, specified during early neurulation. Following EMT, NC cells migrate to various points in the developing embryo where they give rise to a number of tissues including parts of the peripheral nervous system, pigment cells and craniofacial skeleton. Dysregulation of NC development results in many diseases grouped under the term neurocristopathies. As miRNAs are so small, it is difficult to design CRISPR sgRNAs that reproducibly lead to a KO. We have therefore designed a novel approach using two guide RNAs to effectively 'drop out' a miRNA. We have knocked out miR-196a and miR-219 and compared the results to morpholino knockdowns (KD) of the same miRNAs. Validation of efficient CRISPR miRNA KO and phenotype analysis included use of whole-mount in situ hybridization of key NC and neural plate border markers such as Pax3, Xhe2, Sox10 and Snail2, q-RT-PCR and Sanger sequencing. To show specificity we have also rescued the knockout phenotype using miRNA mimics. MiRNA-219 and miR-196a KO's both show loss of NC, altered neural plate and hatching gland phenotypes. Tadpoles show gross craniofacial and pigment phenotypes.
Collapse
Affiliation(s)
- Alice M Godden
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, United Kingdom
| | - Marco Antonaci
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, United Kingdom
| | - Nicole J Ward
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, United Kingdom
| | - Michael van der Lee
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, United Kingdom
| | - Anita Abu-Daya
- King Henry Building, King Henry I St, Portsmouth, PO1 2DY, United Kingdom
| | - Matthew Guille
- King Henry Building, King Henry I St, Portsmouth, PO1 2DY, United Kingdom
| | - Grant N Wheeler
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, United Kingdom.
| |
Collapse
|
8
|
Abstract
Measuring protein thiol redox state is central to understanding redox signalling in health and disease. The lack of a microplate assay to measure target specific protein thiol redox state rate-limits progress on accessibility grounds: redox proteomics is inaccessible to most. Developing a microplate assay is important for accelerating discovery by widening access to protein thiol redox biology. Beyond accessibility, enabling high throughput time- and cost-efficient microplate analysis is important. To meet the pressing need for a microplate assay to measure protein thiol redox state, we present the Antibody-Linked Oxi-State Assay (ALISA). ALISA uses a covalently bound capture antibody to bind a thiol-reactive fluorescent conjugated maleimide (F-MAL) decorated target. The capture antibody-target complex is labelled with an amine-reactive fluorescent N-hydroxysuccinimide ester (F-NHS) to report total protein. The covalent bonds that immobilise the capture antibody to the epoxy group functionalised microplate enable one to selectively elute the target. Target specific redox state is ratiometrically calculated as: F-MAL (i.e., reversible thiol oxidation)/F-NHS (i.e., total protein). After validating the assay principle (i.e., increased target specific reversible thiol oxidation increases the ratio), we used ALISA to determine whether fertilisation-a fundamental biological process-changes Akt, a serine/threonine protein kinase, specific reversible thiol oxidation. Fertilisation significantly decreases Akt specific reversible thiol oxidation in Xenopus laevis 2-cell zygotes compared to unfertilised eggs. ALISA is an accessible microplate assay to advance knowledge of protein thiol redox biology in health and disease.
Collapse
Affiliation(s)
- Anna Noble
- European Xenopus Resource Centre, Portsmouth University, Portsmouth, PO1 2DY, UK
| | - Matthew Guille
- European Xenopus Resource Centre, Portsmouth University, Portsmouth, PO1 2DY, UK
| | | |
Collapse
|
9
|
Moreno MM, Barrell WB, Godwin A, Guille M, Liu KJ. Anaplastic lymphoma kinase (alk), a neuroblastoma associated gene, is expressed in neural crest domains during embryonic development of Xenopus. Gene Expr Patterns 2021; 40:119183. [PMID: 34020009 DOI: 10.1016/j.gep.2021.119183] [Citation(s) in RCA: 1] [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] [Received: 01/26/2021] [Revised: 04/11/2021] [Accepted: 05/04/2021] [Indexed: 10/21/2022]
Abstract
Neuroblastoma is a neural crest-derived paediatric cancer that is the most common and deadly solid extracranial tumour of childhood. It arises when neural crest cells fail to follow their differentiation program to give rise to cells of the sympathoadrenal lineage. These undifferentiated cells can proliferate and migrate, forming tumours mostly found associated with the adrenal glands. Activating mutations in the kinase domain of anaplastic lymphoma kinase (ALK) are linked to high-risk cases, where extensive therapy is ineffective. However, the role of ALK in embryonic development, downstream signal transduction and in metastatic transformation of the neural crest is poorly understood. Here, we demonstrate high conservation of the ALK protein sequences among vertebrates. We then examine alk mRNA expression in the frog models Xenopus laevis and Xenopus tropicalis. Using in situ hybridisation of Xenopus embryos, we show that alk is expressed in neural crest domains throughout development, suggesting a possible role in neuroblastoma initiation. Lastly, RT-qPCR analyses show high levels of alk expression at tadpole stages. Collectively, these data may begin to elucidate how alk functions in neural crest cells and how its deregulation can result in tumorigenesis.
Collapse
Affiliation(s)
- Marcela M Moreno
- Centre for Craniofacial and Regenerative Biology, King's College London, London, SE1 9RT, UK
| | - William B Barrell
- Centre for Craniofacial and Regenerative Biology, King's College London, London, SE1 9RT, UK
| | - Annie Godwin
- European Xenopus Resource Centre, School of Biological Sciences, University of Portsmouth, Portsmouth, PO1 2DY, UK
| | - Matthew Guille
- European Xenopus Resource Centre, School of Biological Sciences, University of Portsmouth, Portsmouth, PO1 2DY, UK
| | - Karen J Liu
- Centre for Craniofacial and Regenerative Biology, King's College London, London, SE1 9RT, UK.
| |
Collapse
|
10
|
Macken WL, Godwin A, Wheway G, Stals K, Nazlamova L, Ellard S, Alfares A, Aloraini T, AlSubaie L, Alfadhel M, Alajaji S, Wai HA, Self J, Douglas AGL, Kao AP, Guille M, Baralle D. Biallelic variants in COPB1 cause a novel, severe intellectual disability syndrome with cataracts and variable microcephaly. Genome Med 2021; 13:34. [PMID: 33632302 PMCID: PMC7908744 DOI: 10.1186/s13073-021-00850-w] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [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: 07/08/2020] [Accepted: 02/11/2021] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Coat protein complex 1 (COPI) is integral in the sorting and retrograde trafficking of proteins and lipids from the Golgi apparatus to the endoplasmic reticulum (ER). In recent years, coat proteins have been implicated in human diseases known collectively as "coatopathies". METHODS Whole exome or genome sequencing of two families with a neuro-developmental syndrome, variable microcephaly and cataracts revealed biallelic variants in COPB1, which encodes the beta-subunit of COPI (β-COP). To investigate Family 1's splice donor site variant, we undertook patient blood RNA studies and CRISPR/Cas9 modelling of this variant in a homologous region of the Xenopus tropicalis genome. To investigate Family 2's missense variant, we studied cellular phenotypes of human retinal epithelium and embryonic kidney cell lines transfected with a COPB1 expression vector into which we had introduced Family 2's mutation. RESULTS We present a new recessive coatopathy typified by severe developmental delay and cataracts and variable microcephaly. A homozygous splice donor site variant in Family 1 results in two aberrant transcripts, one of which causes skipping of exon 8 in COPB1 pre-mRNA, and a 36 amino acid in-frame deletion, resulting in the loss of a motif at a small interaction interface between β-COP and β'-COP. Xenopus tropicalis animals with a homologous mutation, introduced by CRISPR/Cas9 genome editing, recapitulate features of the human syndrome including microcephaly and cataracts. In vitro modelling of the COPB1 c.1651T>G p.Phe551Val variant in Family 2 identifies defective Golgi to ER recycling of this mutant β-COP, with the mutant protein being retarded in the Golgi. CONCLUSIONS This adds to the growing body of evidence that COPI subunits are essential in brain development and human health and underlines the utility of exome and genome sequencing coupled with Xenopus tropicalis CRISPR/Cas modelling for the identification and characterisation of novel rare disease genes.
Collapse
Affiliation(s)
- William L Macken
- Wessex Clinical Genetics Service, Princess Anne Hospital, University Hospital Southampton NHS Foundation Trust, Coxford Rd, Southampton, SO165YA, UK
| | - Annie Godwin
- European Xenopus Resource Centre, University of Portsmouth School of Biological Sciences, King Henry Building, King Henry I Street, Portsmouth, PO1 2DY, UK
| | - Gabrielle Wheway
- Faculty of Medicine, University of Southampton, Duthie Building, Southampton General Hospital, Tremona Road, Southampton, SO16 6YD, UK
| | - Karen Stals
- Exeter Genomics Laboratory, Level 3 RILD building, Royal Devon & Exeter NHS Foundation Trust, Barrack Road, Exeter, EX2 5DW, UK
| | - Liliya Nazlamova
- Faculty of Medicine, University of Southampton, Duthie Building, Southampton General Hospital, Tremona Road, Southampton, SO16 6YD, UK
| | - Sian Ellard
- Exeter Genomics Laboratory, Level 3 RILD building, Royal Devon & Exeter NHS Foundation Trust, Barrack Road, Exeter, EX2 5DW, UK
- University of Exeter Medical School, RILD building, Royal Devon & Exeter NHS Foundation Trust, Barrack Road, Exeter, EX2 5DW, UK
| | - Ahmed Alfares
- Department of Pediatrics, College of Medicine, Qassim University, Qassim, Saudi Arabia
- Department of Pathology and Laboratory Medicine, King Abdulaziz Medical City, Riyadh, Saudi Arabia
| | - Taghrid Aloraini
- Department of Pathology and Laboratory Medicine, King Abdulaziz Medical City, Riyadh, Saudi Arabia
| | - Lamia AlSubaie
- Division of Genetics, Department of Pediatrics, King Abdullah Specialized Children Hospital, King Abdulaziz Medical City, Ministry of National Guard Health Affairs (MNGHA), Riyadh, Saudi Arabia
- King Abdullah International Medical Research Centre, Ministry of National Guard Health Affairs (MNGHA), Riyadh, Saudi Arabia
| | - Majid Alfadhel
- Division of Genetics, Department of Pediatrics, King Abdullah Specialized Children Hospital, King Abdulaziz Medical City, Ministry of National Guard Health Affairs (MNGHA), Riyadh, Saudi Arabia
- King Abdullah International Medical Research Centre, Ministry of National Guard Health Affairs (MNGHA), Riyadh, Saudi Arabia
- King Saud bin Abdulaziz University for Health Sciences, Ministry of National Guard Health Affairs (MNGHA), Riyadh, Saudi Arabia
| | - Sulaiman Alajaji
- King Saud bin Abdulaziz University for Health Sciences, Ministry of National Guard Health Affairs (MNGHA), Riyadh, Saudi Arabia
- Division of Allergy and Clinical Immunology, Department of Pediatrics, King Abdullah Specialized Children Hospital, King Abdulaziz Medical City, Ministry of National Guard Health Affairs (MNGHA), Riyadh, Saudi Arabia
| | - Htoo A Wai
- Faculty of Medicine, University of Southampton, Duthie Building, Southampton General Hospital, Tremona Road, Southampton, SO16 6YD, UK
| | - Jay Self
- Faculty of Medicine, University of Southampton, Duthie Building, Southampton General Hospital, Tremona Road, Southampton, SO16 6YD, UK
| | - Andrew G L Douglas
- Wessex Clinical Genetics Service, Princess Anne Hospital, University Hospital Southampton NHS Foundation Trust, Coxford Rd, Southampton, SO165YA, UK
- Faculty of Medicine, University of Southampton, Duthie Building, Southampton General Hospital, Tremona Road, Southampton, SO16 6YD, UK
| | - Alexander P Kao
- Zeiss Global Centre, School of Mechanical and Design Engineering, University of Portsmouth, Portsmouth, PO1 3DJ, UK
| | - Matthew Guille
- European Xenopus Resource Centre, University of Portsmouth School of Biological Sciences, King Henry Building, King Henry I Street, Portsmouth, PO1 2DY, UK.
| | - Diana Baralle
- Wessex Clinical Genetics Service, Princess Anne Hospital, University Hospital Southampton NHS Foundation Trust, Coxford Rd, Southampton, SO165YA, UK.
- Faculty of Medicine, University of Southampton, Duthie Building, Southampton General Hospital, Tremona Road, Southampton, SO16 6YD, UK.
| |
Collapse
|
11
|
Cobley J, Noble A, Bessell R, Guille M, Husi H. Reversible Thiol Oxidation Inhibits the Mitochondrial ATP Synthase in Xenopus Laevis Oocytes. Antioxidants (Basel) 2020; 9:antiox9030215. [PMID: 32150908 PMCID: PMC7139892 DOI: 10.3390/antiox9030215] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [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: 02/11/2020] [Revised: 03/01/2020] [Accepted: 03/02/2020] [Indexed: 12/15/2022] Open
Abstract
Oocytes are postulated to repress the proton pumps (e.g., complex IV) and ATP synthase to safeguard mitochondrial DNA homoplasmy by curtailing superoxide production. Whether the ATP synthase is inhibited is, however, unknown. Here we show that: oligomycin sensitive ATP synthase activity is significantly greater (~170 vs. 20 nmol/min-1/mg-1) in testes compared to oocytes in Xenopus laevis (X. laevis). Since ATP synthase activity is redox regulated, we explored a regulatory role for reversible thiol oxidation. If a protein thiol inhibits the ATP synthase, then constituent subunits must be reversibly oxidised. Catalyst-free trans-cyclooctene 6-methyltetrazine (TCO-Tz) immunocapture coupled to redox affinity blotting reveals several subunits in F1 (e.g., ATP-α-F1) and Fo (e.g., subunit c) are reversibly oxidised. Catalyst-free TCO-Tz Click PEGylation reveals significant (~60%) reversible ATP-α-F1 oxidation at two evolutionary conserved cysteine residues (C244 and C294) in oocytes. TCO-Tz Click PEGylation reveals ~20% of the total thiols in the ATP synthase are substantially oxidised. Chemically reversing thiol oxidation significantly increased oligomycin sensitive ATP synthase activity from ~12 to 100 nmol/min-1/mg-1 in oocytes. We conclude that reversible thiol oxidation inhibits the mitochondrial ATP synthase in X. laevis oocytes.
Collapse
Affiliation(s)
- James Cobley
- Centre for Health Sciences, University of the Highlands and Islands, Inverness IV2 3JH, UK; (R.B.); (H.H.)
- Correspondence:
| | - Anna Noble
- School of Biological Sciences, European Xenopus Resource Centre, University of Portsmouth, King Henry Building, Portsmouth PO1 2DY, UK; (A.N.); (M.G.)
| | - Rachel Bessell
- Centre for Health Sciences, University of the Highlands and Islands, Inverness IV2 3JH, UK; (R.B.); (H.H.)
| | - Matthew Guille
- School of Biological Sciences, European Xenopus Resource Centre, University of Portsmouth, King Henry Building, Portsmouth PO1 2DY, UK; (A.N.); (M.G.)
| | - Holger Husi
- Centre for Health Sciences, University of the Highlands and Islands, Inverness IV2 3JH, UK; (R.B.); (H.H.)
| |
Collapse
|
12
|
Barbosa S, Greville-Heygate S, Bonnet M, Godwin A, Fagotto-Kaufmann C, Kajava AV, Laouteouet D, Mawby R, Wai HA, Dingemans AJ, Hehir-Kwa J, Willems M, Capri Y, Mehta SG, Cox H, Goudie D, Vansenne F, Turnpenny P, Vincent M, Cogné B, Lesca G, Hertecant J, Rodriguez D, Keren B, Burglen L, Gérard M, Putoux A, Cantagrel V, Siquier-Pernet K, Rio M, Banka S, Sarkar A, Steeves M, Parker M, Clement E, Moutton S, Tran Mau-Them F, Piton A, de Vries BB, Guille M, Debant A, Schmidt S, Baralle D, Baralle D. Opposite Modulation of RAC1 by Mutations in TRIO Is Associated with Distinct, Domain-Specific Neurodevelopmental Disorders. Am J Hum Genet 2020; 106:338-355. [PMID: 32109419 PMCID: PMC7058823 DOI: 10.1016/j.ajhg.2020.01.018] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [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: 10/11/2019] [Accepted: 01/27/2020] [Indexed: 12/13/2022] Open
Abstract
The Rho-guanine nucleotide exchange factor (RhoGEF) TRIO acts as a key regulator of neuronal migration, axonal outgrowth, axon guidance, and synaptogenesis by activating the GTPase RAC1 and modulating actin cytoskeleton remodeling. Pathogenic variants in TRIO are associated with neurodevelopmental diseases, including intellectual disability (ID) and autism spectrum disorders (ASD). Here, we report the largest international cohort of 24 individuals with confirmed pathogenic missense or nonsense variants in TRIO. The nonsense mutations are spread along the TRIO sequence, and affected individuals show variable neurodevelopmental phenotypes. In contrast, missense variants cluster into two mutational hotspots in the TRIO sequence, one in the seventh spectrin repeat and one in the RAC1-activating GEFD1. Although all individuals in this cohort present with developmental delay and a neuro-behavioral phenotype, individuals with a pathogenic variant in the seventh spectrin repeat have a more severe ID associated with macrocephaly than do most individuals with GEFD1 variants, who display milder ID and microcephaly. Functional studies show that the spectrin and GEFD1 variants cause a TRIO-mediated hyper- or hypo-activation of RAC1, respectively, and we observe a striking correlation between RAC1 activation levels and the head size of the affected individuals. In addition, truncations in TRIO GEFD1 in the vertebrate model X. tropicalis induce defects that are concordant with the human phenotype. This work demonstrates distinct clinical and molecular disorders clustering in the GEFD1 and seventh spectrin repeat domains and highlights the importance of tight control of TRIO-RAC1 signaling in neuronal development.
Collapse
Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - Diana Baralle
- Wessex Clinical Genetics, University Hospital Southampton National Health Service Foundation Trust, Southampton SO16 5YA, UK; Human Development and Health, Faculty of Medicine, University of Southampton, Southampton SO16 6YD, UK.
| |
Collapse
|
13
|
Guille M, Michaud M, Hitzel A, Lairez O, Catros F, Ancellin S, Pugnet G, Debard A, Prevot G, Gaches F. Intérêt du TEP-TDM au 18F-FDG dans le bilan étiologique des péricardites. Rev Med Interne 2019. [DOI: 10.1016/j.revmed.2019.10.039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
|
14
|
Cobley JN, Noble A, Jimenez-Fernandez E, Valdivia Moya MT, Guille M, Husi H. Catalyst-free Click PEGylation reveals substantial mitochondrial ATP synthase sub-unit alpha oxidation before and after fertilisation. Redox Biol 2019; 26:101258. [PMID: 31234016 PMCID: PMC6597785 DOI: 10.1016/j.redox.2019.101258] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Revised: 06/10/2019] [Accepted: 06/15/2019] [Indexed: 12/21/2022] Open
Abstract
Using non-reducing Western blotting to assess protein thiol redox state is challenging because most reduced and oxidised forms migrate at the same molecular weight and are, therefore, indistinguishable. While copper catalysed Click chemistry can be used to ligate a polyethylene glycol (PEG) moiety termed Click PEGylation to mass shift the reduced or oxidised form as desired, the potential for copper catalysed auto-oxidation is problematic. Here we define a catalyst-free trans-cyclooctene-methyltetrazine (TCO-Tz) inverse electron demand Diels Alder chemistry approach that affords rapid (k ~2000 M−1 s−1), selective and bio-orthogonal Click PEGylation. We used TCO-Tz Click PEGylation to investigate how fertilisation impacts reversible mitochondrial ATP synthase F1-Fo sub-unit alpha (ATP-α-F1) oxidation—an established molecular correlate of impaired enzyme activity—in Xenopus laevis. TCO-Tz Click PEGylation studies reveal substantial (~65%) reversible ATP-α-F1 oxidation at evolutionary conserved cysteine residues (i.e., C244 and C294) before and after fertilisation. A single thiol is, however, preferentially oxidised likely due to greater solvent exposure during the catalytic cycle. Selective reduction experiments show that: S-glutathionylation accounts for ~50–60% of the reversible oxidation observed, making it the dominant oxidative modification type. Intermolecular disulphide bonds may also contribute due to their relative stability. Substantial reversible ATP-α-F1 oxidation before and after fertilisation is biologically meaningful because it implies low mitochondrial F1-Fo ATP synthase activity. Catalyst-free TCO-Tz Click PEGylation is a valuable new tool to interrogate protein thiol redox state in health and disease. Catalyst-free TCO-Tz Click PEGylation can assess protein thiol redox state. ATP-α-F1 is substantially oxidised before and after fertilisation. S-glutathionylation is the dominant oxidative modification type. A single thiol is preferentially oxidised due to greater solvent exposure. Catalyst-free TCO-Tz Click PEGylation is a valuable new tool.
Collapse
Affiliation(s)
- James N Cobley
- Free Radical Research Group, University of the Highlands and Islands, Centre for Health Sciences, Inverness, IV2 3JH, UK.
| | - Anna Noble
- European Xenopus Resource Centre, University of Portsmouth, School of Biological Sciences, King Henry Building, Portsmouth, PO1 2DY, UK
| | - Eduardo Jimenez-Fernandez
- Free Radical Research Group, University of the Highlands and Islands, Centre for Health Sciences, Inverness, IV2 3JH, UK
| | - Manuel-Thomas Valdivia Moya
- Free Radical Research Group, University of the Highlands and Islands, Centre for Health Sciences, Inverness, IV2 3JH, UK
| | - Matthew Guille
- European Xenopus Resource Centre, University of Portsmouth, School of Biological Sciences, King Henry Building, Portsmouth, PO1 2DY, UK
| | - Holger Husi
- Free Radical Research Group, University of the Highlands and Islands, Centre for Health Sciences, Inverness, IV2 3JH, UK
| |
Collapse
|
15
|
Horb M, Wlizla M, Abu-Daya A, McNamara S, Gajdasik D, Igawa T, Suzuki A, Ogino H, Noble A, Robert J, James-Zorn C, Guille M. Xenopus Resources: Transgenic, Inbred and Mutant Animals, Training Opportunities, and Web-Based Support. Front Physiol 2019; 10:387. [PMID: 31073289 PMCID: PMC6497014 DOI: 10.3389/fphys.2019.00387] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [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: 01/31/2019] [Accepted: 03/21/2019] [Indexed: 02/06/2023] Open
Abstract
Two species of the clawed frog family, Xenopus laevis and X. tropicalis, are widely used as tools to investigate both normal and disease-state biochemistry, genetics, cell biology, and developmental biology. To support both frog specialist and non-specialist scientists needing access to these models for their research, a number of centralized resources exist around the world. These include centers that hold live and frozen stocks of transgenic, inbred and mutant animals and centers that hold molecular resources. This infrastructure is supported by a model organism database. Here, we describe much of this infrastructure and encourage the community to make the best use of it and to guide the resource centers in developing new lines and libraries.
Collapse
Affiliation(s)
- Marko Horb
- National Xenopus Resource, Marine Biological Laboratory, Woods Hole, MA, United States
| | - Marcin Wlizla
- National Xenopus Resource, Marine Biological Laboratory, Woods Hole, MA, United States
| | - Anita Abu-Daya
- European Xenopus Resource Centre, Portsmouth, United Kingdom
| | - Sean McNamara
- National Xenopus Resource, Marine Biological Laboratory, Woods Hole, MA, United States
| | - Dominika Gajdasik
- School of Biological Sciences, King Henry Building, Portsmouth, United Kingdom
| | - Takeshi Igawa
- Amphibian Research Center, Hiroshima University, Higashihiroshima, Japan
| | - Atsushi Suzuki
- Amphibian Research Center, Hiroshima University, Higashihiroshima, Japan
| | - Hajime Ogino
- Amphibian Research Center, Hiroshima University, Higashihiroshima, Japan
| | - Anna Noble
- European Xenopus Resource Centre, Portsmouth, United Kingdom
| | | | - Jacques Robert
- Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, NY, United States
| | - Christina James-Zorn
- Xenbase, Division of Developmental Biology, Cincinnati Children's Research Foundation, Cincinnati, OH, United States
| | - Matthew Guille
- European Xenopus Resource Centre, Portsmouth, United Kingdom.,School of Biological Sciences, King Henry Building, Portsmouth, United Kingdom
| |
Collapse
|
16
|
Guille M, Boumaza X, Delavigne K, Cougoul P, Ollier S, Guenounou S, Comont T, Beyne-Rauzy O. Des nodules, encores des nodules… : infection à mycobactérie atypique chez un patient porteur d’un syndrome myélodysplasique. Rev Med Interne 2018. [DOI: 10.1016/j.revmed.2018.10.148] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
|
17
|
Guille M, Comont T, Boumaza X, Cougoul P, Delavigne K, Albucher J, De Nadai T, Beyne-Rauzy O, Adoue D. Syndrome d’encéphalopathie postérieure réversible compliquant une hémoglobinurie paroxystique nocturne : une association exceptionnelle. Rev Med Interne 2018. [DOI: 10.1016/j.revmed.2018.10.111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
|
18
|
Hassnain Waqas SF, Noble A, Hoang AC, Ampem G, Popp M, Strauß S, Guille M, Röszer T. Adipose tissue macrophages develop from bone marrow-independent progenitors in Xenopus laevis and mouse. J Leukoc Biol 2017; 102:845-855. [PMID: 28642277 PMCID: PMC5574031 DOI: 10.1189/jlb.1a0317-082rr] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [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: 03/02/2017] [Revised: 05/26/2017] [Accepted: 05/27/2017] [Indexed: 12/14/2022] Open
Abstract
ATMs have a metabolic impact in mammals as they contribute to metabolically harmful AT inflammation. The control of the ATM number may have therapeutic potential; however, information on ATM ontogeny is scarce. Whereas it is thought that ATMs develop from circulating monocytes, various tissue-resident Mϕs are capable of self-renewal and develop from BM-independent progenitors without a monocyte intermediate. Here, we show that amphibian AT contains self-renewing ATMs that populate the AT before the establishment of BM hematopoiesis. Xenopus ATMs develop from progenitors of aVBI. In the mouse, a significant amount of ATM develops from the yolk sac, the mammalian equivalent of aVBI. In summary, this study provides evidence for a prenatal origin of ATMs and shows that the study of amphibian ATMs can enhance the understanding of the role of the prenatal environment in ATM development.
Collapse
Affiliation(s)
| | - Anna Noble
- European Xenopus Resource Centre, School of Biological Sciences, University of Portsmouth, Portsmouth, United Kingdom
| | - Anh C Hoang
- Institute of Comparative Molecular Endocrinology, University of Ulm, Ulm, Germany
| | - Grace Ampem
- Institute of Comparative Molecular Endocrinology, University of Ulm, Ulm, Germany
| | - Manuela Popp
- Institute of Comparative Molecular Endocrinology, University of Ulm, Ulm, Germany
| | - Sarah Strauß
- Ambystoma Mexicanum Bioregeneration Center, Department of Plastic, Aesthetic, Hand and Reconstructive Surgery, Hannover Medical School, Medizinische Hochschule Hannover, Hannover, Germany
| | - Matthew Guille
- European Xenopus Resource Centre, School of Biological Sciences, University of Portsmouth, Portsmouth, United Kingdom
| | - Tamás Röszer
- Institute of Comparative Molecular Endocrinology, University of Ulm, Ulm, Germany;
| |
Collapse
|
19
|
Ocasio CA, Sansook S, Jones R, Roberts JM, Scott TG, Tsoureas N, Coxhead P, Guille M, Tizzard GJ, Coles SJ, Hochegger H, Bradner JE, Spencer J. Pojamide: An HDAC3-Selective Ferrocene Analogue with Remarkably Enhanced Redox-Triggered Ferrocenium Activity in Cells. Organometallics 2017. [DOI: 10.1021/acs.organomet.7b00437] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Affiliation(s)
- Cory A. Ocasio
- Genome
Damage and Stability Centre, School of Life Sciences, University of Sussex, Falmer, Brighton BN1 9RQ, U.K
| | - Supojjanee Sansook
- Department
of Chemistry, School of Life Sciences, University of Sussex, Falmer, Brighton BN1 9QJ, U.K
| | - Rhiannon Jones
- Department
of Chemistry, School of Life Sciences, University of Sussex, Falmer, Brighton BN1 9QJ, U.K
| | - Justin M. Roberts
- Department
of Medical Oncology, Dana-Farber Cancer Institute, 360 Longwood Avenue, Boston, Massachusetts 02215, United States
| | - Thomas G. Scott
- Department
of Medical Oncology, Dana-Farber Cancer Institute, 360 Longwood Avenue, Boston, Massachusetts 02215, United States
| | - Nikolaos Tsoureas
- Department
of Chemistry, School of Life Sciences, University of Sussex, Falmer, Brighton BN1 9QJ, U.K
| | - Peter Coxhead
- School
of Biological Sciences, University of Portsmouth, King Henry Building, Portsmouth PO1 2DT, U.K
| | - Matthew Guille
- School
of Biological Sciences, University of Portsmouth, King Henry Building, Portsmouth PO1 2DT, U.K
| | - Graham J. Tizzard
- UK
National Crystallography Service, School of Chemistry, University of Southampton, Highfield Campus, Southampton SO17 1BJ, U.K
| | - Simon J. Coles
- UK
National Crystallography Service, School of Chemistry, University of Southampton, Highfield Campus, Southampton SO17 1BJ, U.K
| | - Helfrid Hochegger
- Genome
Damage and Stability Centre, School of Life Sciences, University of Sussex, Falmer, Brighton BN1 9RQ, U.K
| | - James E. Bradner
- Department
of Medical Oncology, Dana-Farber Cancer Institute, 360 Longwood Avenue, Boston, Massachusetts 02215, United States
| | - John Spencer
- Department
of Chemistry, School of Life Sciences, University of Sussex, Falmer, Brighton BN1 9QJ, U.K
| |
Collapse
|
20
|
Berti F, Kovac M, Daventry H, Schubert F, Guille M, Dietrich S. A protective mechanism for embryonic muscle stem cells in vivo. Mech Dev 2017. [DOI: 10.1016/j.mod.2017.04.466] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
|
21
|
Pearl E, Morrow S, Noble A, Lerebours A, Horb M, Guille M. An optimized method for cryogenic storage of Xenopus sperm to maximise the effectiveness of research using genetically altered frogs. Theriogenology 2017; 92:149-155. [PMID: 28237331 PMCID: PMC5340284 DOI: 10.1016/j.theriogenology.2017.01.007] [Citation(s) in RCA: 21] [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: 07/05/2016] [Revised: 10/26/2016] [Accepted: 01/04/2017] [Indexed: 02/06/2023]
Abstract
Cryogenic storage of sperm from genetically altered Xenopus improves cost effectiveness and animal welfare associated with their use in research; currently it is routine for X. tropicalis but not reliable for X. laevis. Here we compare directly the three published protocols for Xenopus sperm freeze-thaw and determine whether sperm storage temperature, method of testes maceration and delays in the freezing protocols affect successful fertilisation and embryo development in X. laevis. We conclude that the protocol is robust and that the variability observed in fertilisation rates is due to differences between individuals. We show that the embryos made from the frozen-thawed sperm are normal and that the adults they develop into are reproductively indistinguishable from others in the colony. This opens the way for using cryopreserved sperm to distribute dominant genetically altered (GA) lines, potentially saving travel-induced stress to the male frogs, reducing their numbers used and making Xenopus experiments more cost effective. Xenopus cryopreservation is robust using an optimized method. Success is dependent on the quality of animals from which the sperm are taken. Frozen sperm may now be used to distribute lines and wild-type male gametes around the world.
Collapse
Affiliation(s)
- Esther Pearl
- National Xenopus Resource, 7 MBL Street, Woods Hole, MA, 02543, USA
| | - Sean Morrow
- European Xenopus Resource Centre, Institute of Biomedical and Biomolecular Sciences, University of Portsmouth, Portsmouth, PO1 2DT, UK
| | - Anna Noble
- European Xenopus Resource Centre, Institute of Biomedical and Biomolecular Sciences, University of Portsmouth, Portsmouth, PO1 2DT, UK
| | - Adelaide Lerebours
- School of Biological Sciences, University of Portsmouth, Portsmouth, PO1 2DY, UK
| | - Marko Horb
- National Xenopus Resource, 7 MBL Street, Woods Hole, MA, 02543, USA
| | - Matthew Guille
- European Xenopus Resource Centre, Institute of Biomedical and Biomolecular Sciences, University of Portsmouth, Portsmouth, PO1 2DT, UK; School of Biological Sciences, University of Portsmouth, Portsmouth, PO1 2DY, UK.
| |
Collapse
|
22
|
Short S, Peterkin T, Guille M, Patient R, Sharpe C. Short linear motif acquisition, exon formation and alternative splicing determine a pathway to diversity for NCoR-family co-repressors. Open Biol 2016; 5:rsob.150063. [PMID: 26289800 PMCID: PMC4554918 DOI: 10.1098/rsob.150063] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [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: 12/26/2022] Open
Abstract
Vertebrate NCoR-family co-repressors play central roles in the timing of embryo and stem cell differentiation by repressing the activity of a range of transcription factors. They interact with nuclear receptors using short linear motifs (SLiMs) termed co-repressor for nuclear receptor (CoRNR) boxes. Here, we identify the pathway leading to increasing co-repressor diversity across the deuterostomes. The final complement of CoRNR boxes arose in an ancestral cephalochordate, and was encoded in one large exon; the urochordates and vertebrates then split this region between 10 and 12 exons. In Xenopus, alternative splicing is prevalent in NCoR2, but absent in NCoR1. We show for one NCoR1 exon that alternative splicing can be recovered by a single point mutation, suggesting NCoR1 lost the capacity for alternative splicing. Analyses in Xenopus and zebrafish identify that cellular context, rather than gene sequence, predominantly determines species differences in alternative splicing. We identify a pathway to diversity for the NCoR family beginning with the addition of a SLiM, followed by gene duplication, the generation of alternatively spliced isoforms and their differential deployment.
Collapse
Affiliation(s)
- Stephen Short
- Institute of Marine Sciences, School of Biological Science, University of Portsmouth, Portsmouth PO1 2DY, UK
| | - Tessa Peterkin
- The Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Headington, Oxford OX3 9DS, UK
| | - Matthew Guille
- Institute of Biomolecular and Biomedical Science, School of Biological Sciences, University of Portsmouth, Portsmouth PO1 2DY, UK European Xenopus Resource Centre, University of Portsmouth, St Michael's Building, Portsmouth PO1 2DT, UK
| | - Roger Patient
- The Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Headington, Oxford OX3 9DS, UK
| | - Colin Sharpe
- Institute of Biomolecular and Biomedical Science, School of Biological Sciences, University of Portsmouth, Portsmouth PO1 2DY, UK European Xenopus Resource Centre, University of Portsmouth, St Michael's Building, Portsmouth PO1 2DT, UK
| |
Collapse
|
23
|
Roussis IM, Guille M, Myers FA, Scarlett GP. RNA Whole-Mount In situ Hybridisation Proximity Ligation Assay (rISH-PLA), an Assay for Detecting RNA-Protein Complexes in Intact Cells. PLoS One 2016; 11:e0147967. [PMID: 26824753 PMCID: PMC4732756 DOI: 10.1371/journal.pone.0147967] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Accepted: 01/11/2016] [Indexed: 11/19/2022] Open
Abstract
Techniques for studying RNA-protein interactions have lagged behind those for DNA-protein complexes as a consequence of the complexities associated with working with RNA. Here we present a method for the modification of the existing In Situ Hybridisation-Proximity Ligation Assay (ISH-PLA) protocol to adapt it to the study of RNA regulation (rISH-PLA). As proof of principle we used the well-characterised interaction of the Xenopus laevis Staufen RNA binding protein with Vg1 mRNA, the complex of which co-localises to the vegetal pole of Xenopus oocytes. The applicability of both the Stau1 antibody and the Locked Nucleic Acid probe (LNA) recognising Vg1 mRNA were independently validated by whole-mount Immunohistochemistry and whole-mount in situ hybridisation assays respectively prior to combining them in the rISH-PLA assay. The rISH-PLA assay allows the identification of a given RNA-protein complex at subcellular and single cell resolution, thus avoiding the lack of spatial resolution and sensitivity associated with assaying heterogenous cell populations from which conventional RNA-protein interaction detection techniques suffer. This technique will be particularly usefully for studying the activity of RNA binding proteins (RBPs) in complex mixtures of cells, for example tissue sections or whole embryos.
Collapse
Affiliation(s)
- Ioannis M. Roussis
- Biophysics Laboratories, Institute of Biomedical and Biomolecular Sciences, University of Portsmouth, Portsmouth, PO1 2DT, United Kingdom
| | - Matthew Guille
- Biophysics Laboratories, Institute of Biomedical and Biomolecular Sciences, University of Portsmouth, Portsmouth, PO1 2DT, United Kingdom
| | - Fiona A. Myers
- Biophysics Laboratories, Institute of Biomedical and Biomolecular Sciences, University of Portsmouth, Portsmouth, PO1 2DT, United Kingdom
| | - Garry P. Scarlett
- Biophysics Laboratories, Institute of Biomedical and Biomolecular Sciences, University of Portsmouth, Portsmouth, PO1 2DT, United Kingdom
| |
Collapse
|
24
|
Pollock K, Gosálvez J, Arroyo F, López-Fernández C, Guille M, Noble A, Johnston SD. Validation of the sperm chromatin dispersion (SCD) test in the amphibian Xenopus laevis using in situ nick translation and comet assay. Reprod Fertil Dev 2015; 27:1168-74. [DOI: 10.1071/rd14070] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2014] [Accepted: 04/13/2014] [Indexed: 11/23/2022] Open
Abstract
The integrity of sperm DNA is becoming increasingly recognised as an important parameter of semen quality, but there are no published reports of this procedure for any amphibian. The primary aim of this study was to apply a modified sperm chromatin dispersion (SCD) test (Halomax) to an amphibian sperm model (African clawed frog; Xenopus laevis) and to validate the assay against in situ nick translation (ISNT) and the double-comet assay procedure. Inactivated spermatozoa were collected from fresh testes (n = 3). Sperm DNA fragmentation (SDF) for each sperm sample was conducted immediately following activation (T0) and again after 1 h (T1) and 24 h (T24) of incubation at room temperature in order to produce a range of spermatozoa with differing levels of DNA damage. The SCD procedure resulted in the production of three nuclear morphotypes; amphibian sperm morphotype 1 (ASM-1) and ASM-2 showed no evidence of DNA damage, whereas ASM-3 spermatozoa were highly fragmented with large halos of dispersed DNA fragments and a reduced nuclear core. ISNT confirmed that ASM-3 nuclei contained damaged DNA. There was a significant correlation (r = 0.9613) between the levels of ASM-3 detected by the SCD test and SDF revealed by the double-comet assay.
Collapse
|
25
|
Patel H, Chuckowree I, Coxhead P, Guille M, Wang M, Zuckermann A, Williams RSB, Librizzi M, Paranal RM, Bradner JE, Spencer J. Synthesis of hybrid anticancer agents based on kinase and histone deacetylase inhibitors. Med Chem Commun 2014. [DOI: 10.1039/c4md00211c] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A HDAC, kinase inhibitor hybrid, (Z)-N1-(3-((1H-pyrrol-2-yl)methylene)-2-oxoindolin-5-yl)-N8-hydroxyoctanediamide, 6, showed impressive anticancer action in a number of biochemical and cell-based assays.
Collapse
Affiliation(s)
- Hiren Patel
- School of Science at Medway
- University of Greenwich
- Chatham
- UK
| | - Irina Chuckowree
- School of Science at Medway
- University of Greenwich
- Chatham
- UK
- Department of Chemistry
| | - Peter Coxhead
- School of Biological Sciences
- University of Portsmouth
- Portsmouth
- UK
| | - Matthew Guille
- School of Biological Sciences
- University of Portsmouth
- Portsmouth
- UK
| | - Minghua Wang
- Terrence Donnelly Center for Cellular and Biomolecular Research
- University of Toronto
- Toronto
- Canada
| | - Alexandra Zuckermann
- Centre for Biomedical Sciences
- School of Biological Sciences
- Royal Holloway University of London
- Egham
- UK
| | - Robin S. B. Williams
- Centre for Biomedical Sciences
- School of Biological Sciences
- Royal Holloway University of London
- Egham
- UK
| | | | | | | | - John Spencer
- School of Science at Medway
- University of Greenwich
- Chatham
- UK
- Department of Chemistry
| |
Collapse
|
26
|
Lloyd RE, Foster PG, Guille M, Littlewood DTJ. Next generation sequencing and comparative analyses of Xenopus mitogenomes. BMC Genomics 2012; 13:496. [PMID: 22992290 PMCID: PMC3546946 DOI: 10.1186/1471-2164-13-496] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [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] [Received: 06/12/2012] [Accepted: 09/13/2012] [Indexed: 01/09/2023] Open
Abstract
Background Mitochondrial genomes comprise a small but critical component of the total DNA in eukaryotic organisms. They encode several key proteins for the cell’s major energy producing apparatus, the mitochondrial respiratory chain. Additonally, their nucleotide and amino acid sequences are of great utility as markers for systematics, molecular ecology and forensics. Their characterization through nucleotide sequencing is a fundamental starting point in mitogenomics. Methods to amplify complete mitochondrial genomes rapidly and efficiently from microgram quantities of tissue of single individuals are, however, not always available. Here we validate two approaches, which combine long-PCR with Roche 454 pyrosequencing technology, to obtain two complete mitochondrial genomes from individual amphibian species. Results We obtained two new xenopus frogs (Xenopus borealis and X. victorianus) complete mitochondrial genome sequences by means of long-PCR followed by 454 of individual genomes (approach 1) or of multiple pooled genomes (approach 2), the mean depth of coverage per nucleotide was 9823 and 186, respectively. We also characterised and compared the new mitogenomes against their sister taxa; X. laevis and Silurana tropicalis, two of the most intensely studied amphibians. Our results demonstrate how our approaches can be used to obtain complete amphibian mitogenomes with depths of coverage that far surpass traditional primer-walking strategies, at either the same cost or less. Our results also demonstrate: that the size, gene content and order are the same among xenopus mitogenomes and that S. tropicalis form a separate clade to the other xenopus, among which X. laevis and X. victorianus were most closely related. Nucleotide and amino acid diversity was found to vary across the xenopus mitogenomes, with the greatest diversity observed in the Complex 1 gene nad4l and the least diversity observed in Complex 4 genes (cox1-3). All protein-coding genes were shown to be under strong negative (purifying selection), with genes under the strongest pressure (Complex 4) also being the most highly expressed, highlighting their potentially crucial functions in the mitochondrial respiratory chain. Conclusions Next generation sequencing of long-PCR amplicons using single taxon or multi-taxon approaches enabled two new species of Xenopus mtDNA to be fully characterized. We anticipate our complete mitochondrial genome amplification methods to be applicable to other amphibians, helpful for identifying the most appropriate markers for differentiating species, populations and resolving phylogenies, a pressing need since amphibians are undergoing drastic global decline. Our mtDNAs also provide templates for conserved primer design and the assembly of RNA and DNA reads following high throughput “omic” techniques such as RNA- and ChIP-seq. These could help us better understand how processes such mitochondrial replication and gene expression influence xenopus growth and development, as well as how they evolved and are regulated.
Collapse
Affiliation(s)
- Rhiannon E Lloyd
- Julius L. Chambers Biomedical/ Biotechnology Research Institute & Department of Chemistry, North Carolina Central University, 1801 Fayetteville Street, Durham, NC 27707, USA
| | | | | | | |
Collapse
|
27
|
Pearl EJ, Grainger RM, Guille M, Horb ME. Development of Xenopus resource centers: the National Xenopus Resource and the European Xenopus Resource Center. Genesis 2012; 50:155-63. [PMID: 22253050 PMCID: PMC3778656 DOI: 10.1002/dvg.22013] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [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: 09/06/2011] [Accepted: 01/09/2012] [Indexed: 12/25/2022]
Abstract
Xenopus is an essential vertebrate model system for biomedical research that has contributed to important discoveries in many disciplines, including cell biology, molecular biology, physiology, developmental biology, and neurobiology. However, unlike other model systems no central repository/stock center for Xenopus had been established until recently. Similar to mouse, zebrafish, and fly communities, which have established stock centers, Xenopus researchers need to maintain and distribute rapidly growing numbers of inbred, mutant, and transgenic frog strains, along with DNA and protein resources, and individual laboratories struggle to accomplish this efficiently. In the last 5 years, two resource centers were founded to address this need: the European Xenopus Resource Center (EXRC) at the University of Portsmouth in England, and the National Xenopus Resource (NXR) at the Marine Biological Laboratory in Woods Hole, MA. These two centers work together to provide resources and support to the Xenopus research community. The EXRC and NXR serve as stock centers and acquire, produce, maintain and distribute mutant, inbred and transgenic Xenopus laevis and Xenopus tropicalis lines. Independently, the EXRC is a repository for Xenopus cDNAs, fosmids, and antibodies; it also provides oocytes and wild-type frogs within the United Kingdom. The NXR will complement these services by providing research training and promoting intellectual interchange through hosting mini-courses and workshops and offering space for researchers to perform short-term projects at the Marine Biological Laboratory. Together the EXRC and NXR will enable researchers to improve productivity by providing resources and expertise to all levels, from graduate students to experienced PIs. These two centers will also enable investigators that use other animal systems to take advantage of Xenopus' unique experimental features to complement their studies.
Collapse
Affiliation(s)
- Esther J. Pearl
- National Xenopus Resource, Marine Biological Laboratory, 7 MBL St, Woods Hole, MA 02543, USA
| | - Robert M. Grainger
- University of Virginia Department of Biology, Gilmer Hall, University of Virginia, Charlottesville, VA 22904, USA
| | - Matthew Guille
- European Xenopus Resource Center, St Michael’s Building, University of Portsmouth, Portsmouth PO1 2DT, UK
| | - Marko E. Horb
- National Xenopus Resource, Marine Biological Laboratory, 7 MBL St, Woods Hole, MA 02543, USA
- Department of Molecular Biology, Cell Biology & Biochemistry, Brown University, Providence, RI USA
- Eugene Bell Center for Regenerative Biology and Tissue Engineering, Marine Biological Laboratory, Woods Hole, MA USA
| |
Collapse
|
28
|
Abstract
Xenopus tropicalis combine the advantages of X. laevis, for example using explants and targeted gain of function, with the ability to take classical genetics approaches to answering cell and developmental biology questions making it arguably the most versatile of the model organisms. Against this background, husbandry of X. tropicalis is less well developed than for its larger, more robust relative. Here we describe the methods used to keep and breed these frogs successfully.
Collapse
Affiliation(s)
- Alan Jafkins
- European Xenopus Resource Centre, School of Biological Sciences, University of Portsmouth, Portsmouth, England, UK
| | | | | | | | | |
Collapse
|
29
|
Spencer J, Amin J, Boddiboyena R, Packham G, Cavell BE, Syed Alwi SS, Paranal RM, Heightman TD, Wang M, Marsden B, Coxhead P, Guille M, Tizzard GJ, Coles SJ, Bradner. JE. Click JAHAs: conformationally restricted ferrocene-based histone deacetylase inhibitors. Med Chem Commun 2012. [DOI: 10.1039/c1md00203a] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The ferrocene analogue 4b had an IC50 = 4 nM (HDAC1), 180 nM (HDAC8) and was effective in a Xenopus model of tubulin deacetylation. Analogue 4a displayed mainly μM IC50 values against HDACs apart from HDAC6 (IC50 = 69 nM).
Collapse
|
30
|
Spencer J, Amin J, Coxhead P, McGeehan J, Richards CJ, Tizzard GJ, Coles SJ, Bingham JP, Hartley JA, Feng L, Meggers E, Guille M. Size Does Matter. Sterically Demanding Metallocene-Substituted 3-Methylidene-Oxindoles Exhibit Poor Kinase Inhibitory Action. Organometallics 2011. [DOI: 10.1021/om200278j] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Affiliation(s)
- John Spencer
- School of Science, University of Greenwich at Medway, University of Greenwich, Chatham, ME4 4TB, U.K
| | - Jahangir Amin
- School of Science, University of Greenwich at Medway, University of Greenwich, Chatham, ME4 4TB, U.K
| | - Peter Coxhead
- School of Biological Sciences, University of Portsmouth, King Henry Building, Portsmouth, PO1 2DT, U.K
| | - John McGeehan
- School of Biological Sciences, University of Portsmouth, King Henry Building, Portsmouth, PO1 2DT, U.K
| | | | - Graham J. Tizzard
- UK National Crystallography Service, School of Chemistry, University of Southampton, Highfield, Southampton, SO171BJ, U.K
| | - Simon J. Coles
- UK National Crystallography Service, School of Chemistry, University of Southampton, Highfield, Southampton, SO171BJ, U.K
| | - John P. Bingham
- CRUK Drug-DNA Interactions Research Group, UCL Cancer Institute, Paul O'Gorman Building, 72 Huntley Street, London, WC1E 6DD, U.K
| | - John A. Hartley
- CRUK Drug-DNA Interactions Research Group, UCL Cancer Institute, Paul O'Gorman Building, 72 Huntley Street, London, WC1E 6DD, U.K
| | - Li Feng
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein Strasse, D-35032 Marburg, Germany
| | - Eric Meggers
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein Strasse, D-35032 Marburg, Germany
| | - Matthew Guille
- School of Biological Sciences, University of Portsmouth, King Henry Building, Portsmouth, PO1 2DT, U.K
| |
Collapse
|
31
|
Spencer J, Amin J, Callear SK, Tizzard GJ, Coles SJ, Coxhead P, Guille M. Synthesis and evaluation of metallocene containing methylidene-1,3-dihydro-2H-indol-2-ones as kinase inhibitors. Metallomics 2011; 3:600-8. [PMID: 21359402 DOI: 10.1039/c1mt00017a] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
(E)- and (Z)-3-Ferrocenylmethylidene-1,3-dihydro-2H-indol-2-ones 1 have been structurally modified in order to explore SAR against a range of kinases. Of note is the submicromolar to low micromolar inhibition of DYRK3 and 4 by a number of complexes. Screening using Xenopus embryos showed some of the compounds to have potent antiangiogenisis activity.
Collapse
Affiliation(s)
- John Spencer
- School of Science, University of Greenwich at Medway, Central Avenue, Chatham, Kent, ME4 4TB, UK.
| | | | | | | | | | | | | |
Collapse
|
32
|
Cazanove O, Batut J, Scarlett G, Mumford K, Elgar S, Thresh S, Neant I, Moreau M, Guille M. Methylation of Xilf3 by Xprmt1b Alters Its DNA, but Not RNA, Binding Activity. Biochemistry 2008; 47:8350-7. [DOI: 10.1021/bi7008486] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Ophelie Cazanove
- Institute of Biomedical and Biomolecular Sciences, School of Biological Sciences, University of Portsmouth, Portsmouth PO1 2DY, U.K., and Centre de Biologie du Développement, UMR 5547 CNRS/UPS, 118 Route de, Narbonne, 31062 Toulouse Cedex 04, France
| | - Julie Batut
- Institute of Biomedical and Biomolecular Sciences, School of Biological Sciences, University of Portsmouth, Portsmouth PO1 2DY, U.K., and Centre de Biologie du Développement, UMR 5547 CNRS/UPS, 118 Route de, Narbonne, 31062 Toulouse Cedex 04, France
| | - Garry Scarlett
- Institute of Biomedical and Biomolecular Sciences, School of Biological Sciences, University of Portsmouth, Portsmouth PO1 2DY, U.K., and Centre de Biologie du Développement, UMR 5547 CNRS/UPS, 118 Route de, Narbonne, 31062 Toulouse Cedex 04, France
| | - Katherine Mumford
- Institute of Biomedical and Biomolecular Sciences, School of Biological Sciences, University of Portsmouth, Portsmouth PO1 2DY, U.K., and Centre de Biologie du Développement, UMR 5547 CNRS/UPS, 118 Route de, Narbonne, 31062 Toulouse Cedex 04, France
| | - Stuart Elgar
- Institute of Biomedical and Biomolecular Sciences, School of Biological Sciences, University of Portsmouth, Portsmouth PO1 2DY, U.K., and Centre de Biologie du Développement, UMR 5547 CNRS/UPS, 118 Route de, Narbonne, 31062 Toulouse Cedex 04, France
| | - Sarah Thresh
- Institute of Biomedical and Biomolecular Sciences, School of Biological Sciences, University of Portsmouth, Portsmouth PO1 2DY, U.K., and Centre de Biologie du Développement, UMR 5547 CNRS/UPS, 118 Route de, Narbonne, 31062 Toulouse Cedex 04, France
| | - Isabelle Neant
- Institute of Biomedical and Biomolecular Sciences, School of Biological Sciences, University of Portsmouth, Portsmouth PO1 2DY, U.K., and Centre de Biologie du Développement, UMR 5547 CNRS/UPS, 118 Route de, Narbonne, 31062 Toulouse Cedex 04, France
| | - Marc Moreau
- Institute of Biomedical and Biomolecular Sciences, School of Biological Sciences, University of Portsmouth, Portsmouth PO1 2DY, U.K., and Centre de Biologie du Développement, UMR 5547 CNRS/UPS, 118 Route de, Narbonne, 31062 Toulouse Cedex 04, France
| | - Matthew Guille
- Institute of Biomedical and Biomolecular Sciences, School of Biological Sciences, University of Portsmouth, Portsmouth PO1 2DY, U.K., and Centre de Biologie du Développement, UMR 5547 CNRS/UPS, 118 Route de, Narbonne, 31062 Toulouse Cedex 04, France
| |
Collapse
|
33
|
Friedeberg C, Scarlett G, McGeeghan J, Abu-daya A, Guille M, Kneale G. Identification of a structural and functional domain in xNAP1 involved in protein-protein interactions. Nucleic Acids Res 2006; 34:4893-9. [PMID: 16982648 PMCID: PMC1635243 DOI: 10.1093/nar/gkl434] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
xNAP1 (Xenopus nucleosome assembly protein) belongs to the family of nucleosome assembly proteins (NAPs) and shares 92% identity with human and mouse NAP1. NAPs have been reported to have a role in nucleosome assembly, cell cycle regulation, cell proliferation and transcriptional control, although the precise function of NAP1 is still not clear. Here we report the identification of a putative domain of xNAP1 by limited proteolysis. This domain has been mapped in the xNAP1 protein sequence to residues 38–282 and thus lacks the acidic sequences at the N- and C-termini. We have studied this domain and related fragments in vitro and by a functional assay involving over-expression of the protein in Xenopus laevis embryos. Analytical ultracentrifugation shows that removal of the acidic N- and C-terminal regions does not prevent the formation of larger multimers, which are predominantly hexadecamers. Injection of mRNA encoding the full-length xNAP1 or the putative domain and other related constructs into Xenopus embryos gave identical phenotypes. These results are discussed in relation to protein–protein interactions between NAP1 octamers and a possible ‘squelching’ mechanism.
Collapse
Affiliation(s)
| | | | | | | | | | - Geoff Kneale
- To whom correspondence should be addressed. Tel: 0044 2392 842678; Fax: 0044 2392 842053;
| |
Collapse
|
34
|
Brzostowski J, Robinson C, Orford R, Elgar S, Scarlett G, Peterkin T, Malartre M, Kneale G, Wormington M, Guille M. RNA-dependent cytoplasmic anchoring of a transcription factor subunit during Xenopus development. EMBO J 2000; 19:3683-93. [PMID: 10899122 PMCID: PMC313978 DOI: 10.1093/emboj/19.14.3683] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.5] [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: 04/14/2000] [Revised: 05/30/2000] [Accepted: 05/30/2000] [Indexed: 11/14/2022] Open
Abstract
The CCAAT box transcription factor (CBTF) is a multimeric transcription factor that activates expression of the haematopoietic regulatory factor, GATA-2. The 122 kDa subunit of this complex, CBTF(122), is cytoplasmic in fertilized Xenopus eggs and subsequently translocates to the nucleus prior to activation of zygotic GATA-2 transcription at gastrulation. Here we present data suggesting both a role for CBTF(122) prior to its nuclear translocation and the mechanism that retains it in the cytoplasm before the midblastula transition (MBT). CBTF(122) and its variant CBTF(98) are associated with translationally quiescent mRNP complexes. We show that CBTF(122) RNA binding activity is both necessary and sufficient for its cytoplasmic retention during early development. The introduction of an additional nuclear localization signal to CBTF(122) is insufficient to overcome this retention, suggesting that RNA binding acts as a cytoplasmic anchor for CBTF(122). Destruction of endogenous RNA by microinjection of RNase promotes premature nuclear translocation of CBTF(122). Thus, the nuclear translocation of CBTF(122) at the MBT is likely to be coupled to the degradation of maternal mRNA that occurs at that stage.
Collapse
Affiliation(s)
- J Brzostowski
- Department of Biology, University of Virginia, Gilmer Hall, Charlottesville, VA 22903-2477, USA
| | | | | | | | | | | | | | | | | | | |
Collapse
|
35
|
Affiliation(s)
- C Robinson
- Biophysics Laboratories, University of Portsmouth, UK
| | | |
Collapse
|
36
|
Affiliation(s)
- R Orford
- Biophysics Laboratories, University of Portsmouth, UK
| | | | | |
Collapse
|
37
|
Affiliation(s)
- W Moore
- Biophysics Laboratories, University of Portsmouth, UK
| | | |
Collapse
|
38
|
Affiliation(s)
- R Orford
- Biophysics Laboratories, University of Portsmouth, UK
| | | |
Collapse
|
39
|
Affiliation(s)
- M Guille
- Division of Cell and Molecular Biology, University of Portsmouth, UK
| |
Collapse
|
40
|
Gove C, Walmsley M, Nijjar S, Bertwistle D, Guille M, Partington G, Bomford A, Patient R. Over-expression of GATA-6 in Xenopus embryos blocks differentiation of heart precursors. EMBO J 1997; 16:355-68. [PMID: 9029155 PMCID: PMC1169641 DOI: 10.1093/emboj/16.2.355] [Citation(s) in RCA: 98] [Impact Index Per Article: 3.6] [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: 02/03/2023] Open
Abstract
Xenopus GATA-6 transcripts are first detected at the beginning of gastrulation in the mesoderm, and subsequent domains of expression include the field of cells shown to have heart-forming potential. In this region, GATA-6 expression continues only in those cells that go on to form the heart; however, a decrease occurs prior to terminal differentiation. Artificial elevation of GATA-6, but not GATA-1, prevents expression of both cardiac actin and heart-specific myosin light chain. This effect is heart-specific because cardiac actin expression is unaffected in somites. Expression of the earlier marker XNkx-2.5 was unaffected and morphological development of the heart was initiated independently of the establishment of the contractile machinery. We conclude that a reduction in the level of GATA-6 is important for the progression of the cardiomyogenic differentiation programme and that GATA-6 may act to maintain heart cells in the precursor state. At later stages, when the elevated GATA-6 levels had decayed, differentiation ensued but the number of cells contributing to the myocardium had increased, suggesting either that the blocked cells had proliferated or that additional cells had been recruited.
Collapse
Affiliation(s)
- C Gove
- Developmental Biology Research Centre, The Randall Institute, King's College London, UK
| | | | | | | | | | | | | | | |
Collapse
|
41
|
Guille M. A Practical Guide to Molecular Cloning (2nd ed). FEBS Lett 1989. [DOI: 10.1016/0014-5793(89)80695-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
|