1
|
Hop Mice Display Synchronous Hindlimb Locomotion and a Ventrally Fused Lumbar Spinal Cord Caused by a Point Mutation in Ttc26. eNeuro 2022; 9:ENEURO.0518-21.2022. [PMID: 35210288 PMCID: PMC8925726 DOI: 10.1523/eneuro.0518-21.2022] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Revised: 02/01/2022] [Accepted: 02/05/2022] [Indexed: 11/28/2022] Open
Abstract
Identifying the spinal circuits controlling locomotion is critical for unravelling the mechanisms controlling the production of gaits. Development of the circuits governing left-right coordination relies on axon guidance molecules such as ephrins and netrins. To date, no other class of proteins have been shown to play a role during this process. Here, we have analyzed hop mice, which walk with a characteristic hopping gait using their hindlimbs in synchrony. Fictive locomotion experiments suggest that a local defect in the ventral spinal cord contributes to the aberrant locomotor phenotype. Hop mutant spinal cords had severe morphologic defects, including the absence of the ventral midline and a poorly defined border between white and gray matter. The hop mice represent the first model where, exclusively found in the lumbar domain, the left and right components of the central pattern generators (CPGs) are fused with a synchronous hindlimb gait as a functional consequence. These defects were associated with abnormal developmental processes, including a misplaced notochord and reduced induction of ventral progenitor domains. Whereas the underlying mutation in hop mice has been suggested to lie within the Ttc26 gene, other genes in close vicinity have been associated with gait defects. Mouse embryos carrying a CRISPR replicated point mutation within Ttc26 displayed an identical morphologic phenotype. Thus, our data suggest that the assembly of the lumbar CPG network is dependent on fully functional TTC26 protein.
Collapse
|
2
|
Abstract
The RASopathies are a group of disorders caused by a germline mutation in one of the genes encoding a component of the RAS/MAPK pathway. These disorders, including neurofibromatosis type 1, Noonan syndrome, cardiofaciocutaneous syndrome, Costello syndrome and Legius syndrome, among others, have overlapping clinical features due to RAS/MAPK dysfunction. Although several of the RASopathies are very rare, collectively, these disorders are relatively common. In this Review, we discuss the pathogenesis of the RASopathy-associated genetic variants and the knowledge gained about RAS/MAPK signaling that resulted from studying RASopathies. We also describe the cell and animal models of the RASopathies and explore emerging RASopathy genes. Preclinical and clinical experiences with targeted agents as therapeutics for RASopathies are also discussed. Finally, we review how the recently developed drugs targeting RAS/MAPK-driven malignancies, such as inhibitors of RAS activation, direct RAS inhibitors and RAS/MAPK pathway inhibitors, might be leveraged for patients with RASopathies.
Collapse
Affiliation(s)
- Katie E Hebron
- Pediatric Oncology Branch, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892, USA
| | - Edjay Ralph Hernandez
- Pediatric Oncology Branch, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892, USA
| | - Marielle E Yohe
- Pediatric Oncology Branch, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892, USA
| |
Collapse
|
3
|
Fowlkes JL, Thrailkill KM, Bunn RC. RASopathies: The musculoskeletal consequences and their etiology and pathogenesis. Bone 2021; 152:116060. [PMID: 34144233 PMCID: PMC8316423 DOI: 10.1016/j.bone.2021.116060] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Revised: 06/07/2021] [Accepted: 06/10/2021] [Indexed: 01/07/2023]
Abstract
The RASopathies comprise an ever-growing number of clinical syndromes resulting from germline mutations in components of the RAS/MAPK signaling pathway. While multiple organs and tissues may be affected by these mutations, this review will focus on how these mutations specifically impact the musculoskeletal system. Herein, we review the genetics and musculoskeletal phenotypes of these syndromes in humans. We discuss how mutations in the RASopathy syndromes have been studied in translational mouse models. Finally, we discuss how signaling molecules within the RAS/MAPK pathway are involved in normal and abnormal bone biology in the context of osteoblasts, osteoclasts and chondrocytes.
Collapse
Affiliation(s)
- John L Fowlkes
- University of Kentucky Barnstable Brown Diabetes Center, Department of Pediatrics, University of Kentucky College of Medicine, Lexington, KY 40536, United States of America.
| | - Kathryn M Thrailkill
- University of Kentucky Barnstable Brown Diabetes Center, Department of Pediatrics, University of Kentucky College of Medicine, Lexington, KY 40536, United States of America
| | - R Clay Bunn
- University of Kentucky Barnstable Brown Diabetes Center, Department of Pediatrics, University of Kentucky College of Medicine, Lexington, KY 40536, United States of America
| |
Collapse
|
4
|
Vasic V, Jones MSO, Haslinger D, Knaus LS, Schmeisser MJ, Novarino G, Chiocchetti AG. Translating the Role of mTOR- and RAS-Associated Signalopathies in Autism Spectrum Disorder: Models, Mechanisms and Treatment. Genes (Basel) 2021; 12:genes12111746. [PMID: 34828352 PMCID: PMC8624393 DOI: 10.3390/genes12111746] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Revised: 10/25/2021] [Accepted: 10/28/2021] [Indexed: 12/23/2022] Open
Abstract
Mutations affecting mTOR or RAS signaling underlie defined syndromes (the so-called mTORopathies and RASopathies) with high risk for Autism Spectrum Disorder (ASD). These syndromes show a broad variety of somatic phenotypes including cancers, skin abnormalities, heart disease and facial dysmorphisms. Less well studied are the neuropsychiatric symptoms such as ASD. Here, we assess the relevance of these signalopathies in ASD reviewing genetic, human cell model, rodent studies and clinical trials. We conclude that signalopathies have an increased liability for ASD and that, in particular, ASD individuals with dysmorphic features and intellectual disability (ID) have a higher chance for disruptive mutations in RAS- and mTOR-related genes. Studies on rodent and human cell models confirm aberrant neuronal development as the underlying pathology. Human studies further suggest that multiple hits are necessary to induce the respective phenotypes. Recent clinical trials do only report improvements for comorbid conditions such as epilepsy or cancer but not for behavioral aspects. Animal models show that treatment during early development can rescue behavioral phenotypes. Taken together, we suggest investigating the differential roles of mTOR and RAS signaling in both human and rodent models, and to test drug treatment both during and after neuronal development in the available model systems.
Collapse
Affiliation(s)
- Verica Vasic
- Institute for Microscopic Anatomy and Neurobiology, University Medical Center of the Johannes Gutenberg-University, 55131 Mainz, Germany; (V.V.); (M.J.S.)
| | - Mattson S. O. Jones
- Autism Therapy and Research Center of Excellence, Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, University Hospital Frankfurt, 60528 Frankfurt am Main, Germany; (M.S.O.J.); (D.H.)
- Center for Personalized Translational Epilepsy Research (CePTER), Goethe University Frankfurt, 60528 Frankfurt am Main, Germany
| | - Denise Haslinger
- Autism Therapy and Research Center of Excellence, Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, University Hospital Frankfurt, 60528 Frankfurt am Main, Germany; (M.S.O.J.); (D.H.)
- Institute of Science and Technology (IST) Austria, 3400 Klosterneuburg, Austria; (L.S.K.); (G.N.)
| | - Lisa S. Knaus
- Institute of Science and Technology (IST) Austria, 3400 Klosterneuburg, Austria; (L.S.K.); (G.N.)
| | - Michael J. Schmeisser
- Institute for Microscopic Anatomy and Neurobiology, University Medical Center of the Johannes Gutenberg-University, 55131 Mainz, Germany; (V.V.); (M.J.S.)
- Focus Program Translational Neurosciences (FTN), University Medical Center of the Johannes Gutenberg-University, 55131 Mainz, Germany
| | - Gaia Novarino
- Institute of Science and Technology (IST) Austria, 3400 Klosterneuburg, Austria; (L.S.K.); (G.N.)
| | - Andreas G. Chiocchetti
- Autism Therapy and Research Center of Excellence, Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, University Hospital Frankfurt, 60528 Frankfurt am Main, Germany; (M.S.O.J.); (D.H.)
- Center for Personalized Translational Epilepsy Research (CePTER), Goethe University Frankfurt, 60528 Frankfurt am Main, Germany
- Correspondence: ; Tel.: +49-69-6301-80658
| |
Collapse
|
5
|
Gualtieri A, Kyprianou N, Gregory LC, Vignola ML, Nicholson JG, Tan R, Inoue SI, Scagliotti V, Casado P, Blackburn J, Abollo-Jimenez F, Marinelli E, Besser REJ, Högler W, Karen Temple I, Davies JH, Gagunashvili A, Robinson ICAF, Camper SA, Davis SW, Cutillas PR, Gevers EF, Aoki Y, Dattani MT, Gaston-Massuet C. Activating mutations in BRAF disrupt the hypothalamo-pituitary axis leading to hypopituitarism in mice and humans. Nat Commun 2021; 12:2028. [PMID: 33795686 PMCID: PMC8016902 DOI: 10.1038/s41467-021-21712-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Accepted: 01/12/2021] [Indexed: 02/01/2023] Open
Abstract
Germline mutations in BRAF and other components of the MAPK pathway are associated with the congenital syndromes collectively known as RASopathies. Here, we report the association of Septo-Optic Dysplasia (SOD) including hypopituitarism and Cardio-Facio-Cutaneous (CFC) syndrome in patients harbouring mutations in BRAF. Phosphoproteomic analyses demonstrate that these genetic variants are gain-of-function mutations leading to activation of the MAPK pathway. Activation of the MAPK pathway by conditional expression of the BrafV600E/+ allele, or the knock-in BrafQ241R/+ allele (corresponding to the most frequent human CFC-causing mutation, BRAF p.Q257R), leads to abnormal cell lineage determination and terminal differentiation of hormone-producing cells, causing hypopituitarism. Expression of the BrafV600E/+ allele in embryonic pituitary progenitors leads to an increased expression of cell cycle inhibitors, cell growth arrest and apoptosis, but not tumour formation. Our findings show a critical role of BRAF in hypothalamo-pituitary-axis development both in mouse and human and implicate mutations found in RASopathies as a cause of endocrine deficiencies in humans.
Collapse
Affiliation(s)
- Angelica Gualtieri
- Centre for Endocrinology, William Harvey Research Institute, Barts & the London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | - Nikolina Kyprianou
- Centre for Endocrinology, William Harvey Research Institute, Barts & the London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | - Louise C Gregory
- Genetics and Genomic Medicine Research and Teaching Department, UCL, Great Ormond Street Institute of Child Health, London, UK
| | - Maria Lillina Vignola
- Centre for Endocrinology, William Harvey Research Institute, Barts & the London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | - James G Nicholson
- Centre for Endocrinology, William Harvey Research Institute, Barts & the London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | - Rachael Tan
- Centre for Endocrinology, William Harvey Research Institute, Barts & the London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | - Shin-Ichi Inoue
- Department of Medical Genetics, Tohoku University School of Medicine, Sendai, Japan
| | - Valeria Scagliotti
- Centre for Endocrinology, William Harvey Research Institute, Barts & the London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | - Pedro Casado
- Integrative Cell Signalling and Proteomics, Centre for Haemato-Oncology, Barts Cancer Institute, Queen Mary University of London, London, UK
| | - James Blackburn
- Centre for Endocrinology, William Harvey Research Institute, Barts & the London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | - Fernando Abollo-Jimenez
- Centre for Endocrinology, William Harvey Research Institute, Barts & the London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | - Eugenia Marinelli
- Centre for Endocrinology, William Harvey Research Institute, Barts & the London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | - Rachael E J Besser
- Genetics and Genomic Medicine Research and Teaching Department, UCL, Great Ormond Street Institute of Child Health, London, UK
| | - Wolfgang Högler
- Department of Paediatrics and Adolescent Medicine, Johannes Kepler University Linz, Linz, Austria
- Institute of Metabolism and Systems Research, University of Birmingham, Birmingham, UK
| | - I Karen Temple
- Faculty of Medicine, University of Southampton, Southampton, UK
| | - Justin H Davies
- Child Health Directorate, University of Southampton, Southampton, UK
- Human Development and Health, Faculty of Medicine University of Southampton and Wessex Clinical Genetics Service, Southampton, UK
| | - Andrey Gagunashvili
- NIHR Biomedical Research Centre, Great Ormond Street Hospital, Children NHS Foundation Trust and UCL, London, UK
| | | | - Sally A Camper
- Department of Human Genetics, University of Michigan, Ann Arbor, MI, USA
| | - Shannon W Davis
- Department of Biological Sciences, University of South Carolina, Columbia, SC, USA
| | - Pedro R Cutillas
- Integrative Cell Signalling and Proteomics, Centre for Haemato-Oncology, Barts Cancer Institute, Queen Mary University of London, London, UK
| | - Evelien F Gevers
- Centre for Endocrinology, William Harvey Research Institute, Barts & the London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | - Yoko Aoki
- Department of Medical Genetics, Tohoku University School of Medicine, Sendai, Japan
| | - Mehul T Dattani
- Genetics and Genomic Medicine Research and Teaching Department, UCL, Great Ormond Street Institute of Child Health, London, UK
| | - Carles Gaston-Massuet
- Centre for Endocrinology, William Harvey Research Institute, Barts & the London School of Medicine and Dentistry, Queen Mary University of London, London, UK.
| |
Collapse
|
6
|
Kang M, Lee YS. The impact of RASopathy-associated mutations on CNS development in mice and humans. Mol Brain 2019; 12:96. [PMID: 31752929 PMCID: PMC6873535 DOI: 10.1186/s13041-019-0517-5] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Accepted: 10/28/2019] [Indexed: 01/04/2023] Open
Abstract
The RAS signaling pathway is involved in the regulation of developmental processes, including cell growth, proliferation, and differentiation, in the central nervous system (CNS). Germline mutations in the RAS signaling pathway genes are associated with a group of neurodevelopmental disorders, collectively called RASopathy, which includes neurofibromatosis type 1, Noonan syndrome, cardio-facio-cutaneous syndrome, and Costello syndrome. Most mutations associated with RASopathies increase the activity of the RAS-ERK signaling pathway, and therefore, most individuals with RASopathies share common phenotypes, such as a short stature, heart defects, facial abnormalities, and cognitive impairments, which are often accompanied by abnormal CNS development. Recent studies using mouse models of RASopathies demonstrated that particular mutations associated with each disorder disrupt CNS development in a mutation-specific manner. Here, we reviewed the recent literatures that investigated the developmental role of RASopathy-associated mutations using mutant mice, which provided insights into the specific contribution of RAS-ERK signaling molecules to CNS development and the subsequent impact on cognitive function in adult mice.
Collapse
Affiliation(s)
- Minkyung Kang
- Department of Physiology, Seoul National University College of Medicine, 103 Daehak-ro, Jongro-gu, Seoul, 03080, South Korea.,Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul, 03080, Korea
| | - Yong-Seok Lee
- Department of Physiology, Seoul National University College of Medicine, 103 Daehak-ro, Jongro-gu, Seoul, 03080, South Korea. .,Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul, 03080, Korea. .,Neuroscience Research Institute, Seoul National University College of Medicine, 103 Daehak-ro, Jongro-gu, Seoul, 03080, South Korea.
| |
Collapse
|
7
|
Inoue SI, Morozumi N, Yoshikiyo K, Maeda H, Aoki Y. C-type natriuretic peptide improves growth retardation in a mouse model of cardio-facio-cutaneous syndrome. Hum Mol Genet 2019; 28:74-83. [PMID: 30239744 DOI: 10.1093/hmg/ddy333] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2018] [Accepted: 09/13/2018] [Indexed: 12/23/2022] Open
Abstract
Cardio-facio-cutaneous (CFC) syndrome, a genetic disorder caused by germline mutations in BRAF, KRAS, MAP2K1 and MAP2K2, is characterized by growth retardation, heart defects, dysmorphic facial appearance and dermatologic abnormalities. We have previously reported that knock-in mice expressing the CFC syndrome-associated mutation, Braf Q241R, showed growth retardation because of gastrointestinal dysfunction. However, other factors associated with growth retardation, including chondrogenesis and endocrinological profile, have not been examined. Here, we show that 3- and 4-week-old BrafQ241R/+ mice have decreased body weight and length, as well as reduced growth plate width in the proximal tibiae. Furthermore, proliferative and hypertrophic chondrocyte zones of the growth plate were reduced in BrafQ241R/+ mice compared with Braf+/+ mice. Immunohistological analysis revealed that extracellular signal-regulated kinase (ERK) activation was enhanced in hypertrophic chondrocytes in BrafQ241R/+ mice. In accordance with growth retardation and reduced growth plate width, decreased serum levels of insulin-like growth factor 1 (IGF-1) and IGF binding protein 3 (IGFBP-3) were observed in BrafQ241R/+ mice at 3 and 4 weeks of age. Treatment with C-type natriuretic peptide (CNP), a stimulator of endochondral bone growth and a potent inhibitor of the FGFR3-RAF1-MEK/ERK signaling, increased body and tail lengths in Braf+/+ and BrafQ241R/+ mice. In conclusion, ERK activation in chondrocytes and low serum IGF-1/IGFBP-3 levels could be associated with the growth retardation observed in BrafQ241R/+ mice. Our data also suggest that CNP is a potential therapeutic target in CFC syndrome.
Collapse
Affiliation(s)
- Shin-Ichi Inoue
- Department of Medical Genetics, Tohoku University School of Medicine, Sendai
| | - Naomi Morozumi
- Immunology and Inflammatory Disease Field, Asubio Pharma Co., Ltd, Kobe
| | | | - Hiroaki Maeda
- Immunology and Inflammatory Disease Field, Asubio Pharma Co., Ltd, Kobe.,End-Organ Disease Laboratories, Daiichi Sankyo Co., Ltd, Tokyo, Japan
| | - Yoko Aoki
- Department of Medical Genetics, Tohoku University School of Medicine, Sendai
| |
Collapse
|
8
|
Takahara S, Inoue SI, Miyagawa-Tomita S, Matsuura K, Nakashima Y, Niihori T, Matsubara Y, Saiki Y, Aoki Y. New Noonan syndrome model mice with RIT1 mutation exhibit cardiac hypertrophy and susceptibility to β-adrenergic stimulation-induced cardiac fibrosis. EBioMedicine 2019; 42:43-53. [PMID: 30898653 PMCID: PMC6491386 DOI: 10.1016/j.ebiom.2019.03.014] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Revised: 02/27/2019] [Accepted: 03/06/2019] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND Noonan syndrome (NS) is a genetic disorder characterized by short stature, a distinctive facial appearance, and heart defects. We recently discovered a novel NS gene, RIT1, which is a member of the RAS subfamily of small GTPases. NS patients with RIT1 mutations have a high incidence of hypertrophic cardiomyopathy and edematous phenotype, but the specific role of RIT1 remains unclear. METHODS To investigate how germline RIT1 mutations cause NS, we generated knock-in mice that carried a NS-associated Rit1 A57G mutation (Rit1A57G/+). We investigated the phenotypes of Rit1A57G/+ mice in fetal and adult stages as well as the effects of isoproterenol on cardiac function in Rit1A57G/+ mice. FINDINGS Rit1A57G/+ embryos exhibited decreased viability, edema, subcutaneous hemorrhage and AKT activation. Surviving Rit1A57G/+ mice had a short stature, craniofacial abnormalities and splenomegaly. Cardiac hypertrophy and cardiac fibrosis with increased expression of S100A4, vimentin and periostin were observed in Rit1A57G/+ mice compared to Rit1+/+ mice. Upon isoproterenol stimulation, cardiac fibrosis was drastically increased in Rit1A57G/+ mice. Phosphorylated (at Thr308) AKT levels were also elevated in isoproterenol-treated Rit1A57G/+ hearts. INTERPRETATION The A57G mutation in Rit1 causes cardiac hypertrophy, fibrosis and other NS-associated features. Biochemical analysis indicates that the AKT signaling pathway might be related to downstream signaling in the RIT1 A57G mutant at a developmental stage and under β-adrenergic stimulation in the heart. FUND: The Grants-in-Aid were provided by the Practical Research Project for Rare/Intractable Diseases from the Japan Agency for Medical Research and Development, the Japan Society for the Promotion of Science KAKENHI Grant.
Collapse
Affiliation(s)
- Shingo Takahara
- Department of Medical Genetics, Tohoku University Graduate School of Medicine, Sendai, Japan; Division of Cardiovascular Surgery, Graduate School of Medicine, Tohoku University, Sendai, Japan
| | - Shin-Ichi Inoue
- Department of Medical Genetics, Tohoku University Graduate School of Medicine, Sendai, Japan.
| | - Sachiko Miyagawa-Tomita
- Department of Pediatric Cardiology, Tokyo Women's Medical University, Tokyo, Japan; Department of Physiological Chemistry and Metabolism, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan; Department of Animal Nursing Science, Yamazaki University of Animal Health Technology, Tokyo, Japan
| | - Katsuhisa Matsuura
- Institute of Advanced Biomedical Engineering and Science, Tokyo Women's Medical University, Tokyo, Japan; Department of Cardiology, Tokyo Women's Medical University, Tokyo, Japan
| | - Yasumi Nakashima
- Department of Pediatrics, Seirei Hamamatsu General Hospital, Hamamatsu, Japan
| | - Tetsuya Niihori
- Department of Medical Genetics, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Yoichi Matsubara
- Department of Medical Genetics, Tohoku University Graduate School of Medicine, Sendai, Japan; National Center for Child Health and Development, Tokyo, Japan
| | - Yoshikatsu Saiki
- Division of Cardiovascular Surgery, Graduate School of Medicine, Tohoku University, Sendai, Japan
| | - Yoko Aoki
- Department of Medical Genetics, Tohoku University Graduate School of Medicine, Sendai, Japan.
| |
Collapse
|
9
|
Abstract
The MAPK pathway is a prominent intracellular signaling pathway regulating various intracellular functions. Components of this pathway are mutated in a related collection of congenital syndromes collectively referred to as neuro-cardio-facio-cutaneous syndromes (NCFC) or Rasopathies. Recently, it has been appreciated that these disorders are associated with autism spectrum disorders (ASD). In addition, idiopathic ASD has also implicated the MAPK signaling cascade as a common pathway that is affected by many of the genetic variants that have been found to be linked to ASDs. This chapter describes the components of the MAPK pathway and how it is regulated. Furthermore, this chapter will highlight the various functions of the MAPK pathway during both embryonic development of the central nervous system (CNS) and its roles in neuronal physiology and ultimately, behavior. Finally, we will summarize the perturbations to MAPK signaling in various models of autism spectrum disorders and Rasopathies to highlight how dysregulation of this pivotal pathway may contribute to the pathogenesis of autism.
Collapse
|
10
|
Inoue SI, Takahara S, Yoshikawa T, Niihori T, Yanai K, Matsubara Y, Aoki Y. Activated Braf induces esophageal dilation and gastric epithelial hyperplasia in mice. Hum Mol Genet 2018; 26:4715-4727. [PMID: 28973166 DOI: 10.1093/hmg/ddx354] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2017] [Accepted: 08/23/2017] [Indexed: 12/17/2022] Open
Abstract
Germline mutations in BRAF are a major cause of cardio-facio-cutaneous (CFC) syndrome, which is characterized by heart defects, characteristic craniofacial dysmorphology and dermatologic abnormalities. Patients with CFC syndrome also commonly show gastrointestinal dysfunction, including feeding and swallowing difficulties and gastroesophageal reflux. We have previously found that knock-in mice expressing a Braf Q241R mutation exhibit CFC syndrome-related phenotypes, such as growth retardation, craniofacial dysmorphisms, congenital heart defects and learning deficits. However, it remains unclear whether BrafQ241R/+ mice exhibit gastrointestinal dysfunction. Here, we report that BrafQ241R/+ mice have neonatal feeding difficulties and esophageal dilation. The esophagus tissues from BrafQ241R/+ mice displayed incomplete replacement of smooth muscle with skeletal muscle and decreased contraction. Furthermore, the BrafQ241R/+ mice showed hyperkeratosis and a thickened muscle layer in the forestomach. Treatment with MEK inhibitors ameliorated the growth retardation, esophageal dilation, hyperkeratosis and thickened muscle layer in the forestomach in BrafQ241R/+ mice. The esophageal dilation with aberrant skeletal-smooth muscle boundary in BrafQ241R/+ mice were recovered after treatment with the histone H3K27 demethylase inhibitor GSK-J4. Our results provide clues to elucidate the pathogenesis and possible treatment of gastrointestinal dysfunction and failure to thrive in patients with CFC syndrome.
Collapse
Affiliation(s)
| | - Shingo Takahara
- Department of Medical Genetics.,Department of Cardiovascular Surgery
| | - Takeo Yoshikawa
- Department of Pharmacology, Tohoku University School of Medicine, Sendai, Japan
| | | | - Kazuhiko Yanai
- Department of Pharmacology, Tohoku University School of Medicine, Sendai, Japan
| | - Yoichi Matsubara
- Department of Medical Genetics.,National Research Institute for Child Health and Development, Tokyo, Japan
| | | |
Collapse
|
11
|
Aoidi R, Houde N, Landry-Truchon K, Holter M, Jacquet K, Charron L, Krishnaswami SR, Yu BD, Rauen KA, Bisson N, Newbern J, Charron J. Mek1Y130C mice recapitulate aspects of human cardio-facio-cutaneous syndrome. Dis Model Mech 2018; 11:dmm.031278. [PMID: 29590634 PMCID: PMC5897723 DOI: 10.1242/dmm.031278] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Accepted: 02/07/2018] [Indexed: 12/28/2022] Open
Abstract
The RAS/MAPK signaling pathway is one of the most investigated pathways, owing to its established role in numerous cellular processes and implication in cancer. Germline mutations in genes encoding members of the RAS/MAPK pathway also cause severe developmental syndromes collectively known as RASopathies. These syndromes share overlapping characteristics, including craniofacial dysmorphology, cardiac malformations, cutaneous abnormalities and developmental delay. Cardio-facio-cutaneous syndrome (CFC) is a rare RASopathy associated with mutations in BRAF, KRAS, MEK1 (MAP2K1) and MEK2 (MAP2K2). MEK1 and MEK2 mutations are found in ∼25% of the CFC patients and the MEK1Y130C substitution is the most common one. However, little is known about the origins and mechanisms responsible for the development of CFC. To our knowledge, no mouse model carrying RASopathy-linked Mek1 or Mek2 gene mutations has been reported. To investigate the molecular and developmental consequences of the Mek1Y130C mutation, we generated a mouse line carrying this mutation. Analysis of mice from a Mek1 allelic series revealed that the Mek1Y130C allele expresses both wild-type and Y130C mutant forms of MEK1. However, despite reduced levels of MEK1 protein and the lower abundance of MEK1 Y130C protein than wild type, Mek1Y130C mutants showed increased ERK (MAPK) protein activation in response to growth factors, supporting a role for MEK1 Y130C in hyperactivation of the RAS/MAPK pathway, leading to CFC. Mek1Y130C mutant mice exhibited pulmonary artery stenosis, cranial dysmorphia and neurological anomalies, including increased numbers of GFAP+ astrocytes and Olig2+ oligodendrocytes in regions of the cerebral cortex. These data indicate that the Mek1Y130C mutation recapitulates major aspects of CFC, providing a new animal model to investigate the physiopathology of this RASopathy. This article has an associated First Person interview with the first author of the paper. Summary: A mouse model for cardio-facio-cutaneous syndrome caused by MEK1 Y130C mutant protein reveals the role of hyperactivation of the RAS/MAPK pathway in the development of the syndrome.
Collapse
Affiliation(s)
- Rifdat Aoidi
- Centre de recherche sur le cancer de l'Université Laval, CRCHU de Québec, L'Hôtel-Dieu de Québec, Québec G1R 3S3, Canada.,Department of Molecular Biology, Medical Biochemistry and Pathology, Université Laval, Québec G1V 0A6, Canada
| | - Nicolas Houde
- Centre de recherche sur le cancer de l'Université Laval, CRCHU de Québec, L'Hôtel-Dieu de Québec, Québec G1R 3S3, Canada.,Department of Molecular Biology, Medical Biochemistry and Pathology, Université Laval, Québec G1V 0A6, Canada
| | - Kim Landry-Truchon
- Centre de recherche sur le cancer de l'Université Laval, CRCHU de Québec, L'Hôtel-Dieu de Québec, Québec G1R 3S3, Canada.,Department of Molecular Biology, Medical Biochemistry and Pathology, Université Laval, Québec G1V 0A6, Canada
| | - Michael Holter
- School of Life Sciences, Arizona State University, Tempe, AZ 85281, USA
| | - Kevin Jacquet
- Centre de recherche sur le cancer de l'Université Laval, CRCHU de Québec, L'Hôtel-Dieu de Québec, Québec G1R 3S3, Canada.,Department of Molecular Biology, Medical Biochemistry and Pathology, Université Laval, Québec G1V 0A6, Canada
| | - Louis Charron
- Centre de recherche sur le cancer de l'Université Laval, CRCHU de Québec, L'Hôtel-Dieu de Québec, Québec G1R 3S3, Canada
| | - Suguna Rani Krishnaswami
- Institute for Genomic Medicine, Division of Dermatology, University of California San Diego, La Jolla, CA 92093-0761, USA
| | - Benjamin D Yu
- Institute for Genomic Medicine, Division of Dermatology, University of California San Diego, La Jolla, CA 92093-0761, USA.,Interpreta Inc., San Diego, CA 92121, USA
| | - Katherine A Rauen
- Department of Pediatrics, Division of Genomic Medicine, University of California Davis, Sacramento, CA 95817, USA
| | - Nicolas Bisson
- Centre de recherche sur le cancer de l'Université Laval, CRCHU de Québec, L'Hôtel-Dieu de Québec, Québec G1R 3S3, Canada.,Department of Molecular Biology, Medical Biochemistry and Pathology, Université Laval, Québec G1V 0A6, Canada
| | - Jason Newbern
- School of Life Sciences, Arizona State University, Tempe, AZ 85281, USA
| | - Jean Charron
- Centre de recherche sur le cancer de l'Université Laval, CRCHU de Québec, L'Hôtel-Dieu de Québec, Québec G1R 3S3, Canada .,Department of Molecular Biology, Medical Biochemistry and Pathology, Université Laval, Québec G1V 0A6, Canada
| |
Collapse
|
12
|
Oba D, Inoue SI, Miyagawa-Tomita S, Nakashima Y, Niihori T, Yamaguchi S, Matsubara Y, Aoki Y. Mice with an Oncogenic HRAS Mutation are Resistant to High-Fat Diet-Induced Obesity and Exhibit Impaired Hepatic Energy Homeostasis. EBioMedicine 2017; 27:138-150. [PMID: 29254681 PMCID: PMC5828294 DOI: 10.1016/j.ebiom.2017.11.029] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2017] [Revised: 10/30/2017] [Accepted: 11/09/2017] [Indexed: 12/16/2022] Open
Abstract
Costello syndrome is a “RASopathy” that is characterized by growth retardation, dysmorphic facial appearance, hypertrophic cardiomyopathy and tumor predisposition. > 80% of patients with Costello syndrome harbor a heterozygous germline G12S mutation in HRAS. Altered metabolic regulation has been suspected because patients with Costello syndrome exhibit hypoketotic hypoglycemia and increased resting energy expenditure, and their growth is severely retarded. To examine the mechanisms of energy reprogramming by HRAS activation in vivo, we generated knock-in mice expressing a heterozygous Hras G12S mutation (HrasG12S/+ mice) as a mouse model of Costello syndrome. On a high-fat diet, HrasG12S/+ mice developed a lean phenotype with microvesicular hepatic steatosis, resulting in early death compared with wild-type mice. Under starvation conditions, hypoketosis and elevated blood levels of long-chain fatty acylcarnitines were observed, suggesting impaired mitochondrial fatty acid oxidation. Our findings suggest that the oncogenic Hras mutation modulates energy homeostasis in vivo. Mice expressing Hras G12S (HrasG12S/+) showed Costello syndrome-like phenotypes, including craniofacial and cardiac defects. HrasG12S/+ mice are resistant to high-fat diet (HFD)-induced obesity, showing microvesicular hepatic steatosis. Upon fasting, HFD-fed HrasG12S/+ mice show abnormal hepatic fatty acid oxidation, hypoketosis and early hypoglycemia.
Costello syndrome is a congenital anomaly syndrome, which is caused by germline mutations in HRAS oncogene. Altered metabolic regulation has been suspected because patients with Costello syndrome exhibit hypoketotic hypoglycemia and increased resting energy expenditure, and growth retardation. Here, we generated a mouse model for Costello syndrome expressing a Hras G12S mutation, which showed craniofacial and heart abnormalities. On a high-fat diet, mutant mice exhibited a lean phenotype with poor weight gain and microvesicular hepatic steatosis. Under starvation conditions, impaired mitochondrial fatty acid oxidation has been observed. These results suggest that oncogenic RAS signaling in mice modulates energy homeostasis in vivo.
Collapse
Affiliation(s)
- Daiju Oba
- Department of Medical Genetics, Tohoku University School of Medicine, Sendai, Japan
| | - Shin-Ichi Inoue
- Department of Medical Genetics, Tohoku University School of Medicine, Sendai, Japan.
| | - Sachiko Miyagawa-Tomita
- Department of Pediatric Cardiology, Tokyo Women's Medical University, Tokyo, Japan; Division of Cardiovascular Development and Differentiation, Medical Research Institute, Tokyo Women's Medical University, Tokyo, Japan; Department of Veterinary Technology, Yamazaki gakuen University, Tokyo, Japan
| | - Yasumi Nakashima
- Department of Pediatrics, Seirei Hamamatsu General Hospital, Shizuoka, Japan
| | - Tetsuya Niihori
- Department of Medical Genetics, Tohoku University School of Medicine, Sendai, Japan
| | - Seiji Yamaguchi
- Department of Pediatrics, Shimane University, Faculty of Medicine, Shimane, Japan
| | - Yoichi Matsubara
- Department of Medical Genetics, Tohoku University School of Medicine, Sendai, Japan; National Research Institute for Child Health and Development, Tokyo, Japan
| | - Yoko Aoki
- Department of Medical Genetics, Tohoku University School of Medicine, Sendai, Japan.
| |
Collapse
|
13
|
Impaired Osteogenesis of Disease-Specific Induced Pluripotent Stem Cells Derived from a CFC Syndrome Patient. Int J Mol Sci 2017; 18:ijms18122591. [PMID: 29194391 PMCID: PMC5751194 DOI: 10.3390/ijms18122591] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Revised: 11/28/2017] [Accepted: 11/29/2017] [Indexed: 12/21/2022] Open
Abstract
Cardiofaciocutaneous (CFC) syndrome is a rare genetic disorder caused by mutations in the extracellular signal-regulated kinase (ERK) signaling. However, little is known about how aberrant ERK signaling is associated with the defective bone development manifested in most CFC syndrome patients. In this study, induced pluripotent stem cells (iPSCs) were generated from dermal fibroblasts of a CFC syndrome patient having rapidly accelerated fibrosarcoma kinase B (BRAF) gain-of-function mutation. CFC-iPSCs were differentiated into mesenchymal stem cells (CFC-MSCs) and further induced to osteoblasts in vitro. The osteogenic defects of CFC-MSCs were revealed by alkaline phosphatase activity assay, mineralization assay, quantitative real-time polymerase chain reaction (qRT-PCR), and western blotting. Osteogenesis of CFC-MSCs was attenuated compared to wild-type (WT)-MSCs. In addition to activated ERK signaling, increased p-SMAD2 and decreased p-SMAD1 were observed in CFC-MSCs during osteogenesis. The defective osteogenesis of CFC-MSCs was rescued by inhibition of ERK signaling and SMAD2 signaling or activation of SMAD1 signaling. Importantly, activation of ERK signaling and SMAD2 signaling or inhibition of SMAD1 signaling recapitulated the impaired osteogenesis in WT-MSCs. Our findings indicate that SMAD2 signaling and SMAD1 signaling as well as ERK signaling are responsible for defective early bone development in CFC syndrome, providing a novel insight on the pathological mechanism and therapeutic targets.
Collapse
|
14
|
Borrie SC, Brems H, Legius E, Bagni C. Cognitive Dysfunctions in Intellectual Disabilities: The Contributions of the Ras-MAPK and PI3K-AKT-mTOR Pathways. Annu Rev Genomics Hum Genet 2017; 18:115-142. [DOI: 10.1146/annurev-genom-091416-035332] [Citation(s) in RCA: 87] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Sarah C. Borrie
- Department of Human Genetics, KU Leuven, 3000 Leuven, Belgium
| | - Hilde Brems
- Department of Human Genetics, KU Leuven, 3000 Leuven, Belgium
| | - Eric Legius
- Department of Human Genetics, KU Leuven, 3000 Leuven, Belgium
| | - Claudia Bagni
- Department of Human Genetics, KU Leuven, 3000 Leuven, Belgium
- Department of Fundamental Neuroscience, University of Lausanne, 1005 Lausanne, Switzerland
- Department of Biomedicine and Prevention, University of Rome Tor Vergata, 00173 Rome, Italy
| |
Collapse
|
15
|
Zhong J. RAS and downstream RAF-MEK and PI3K-AKT signaling in neuronal development, function and dysfunction. Biol Chem 2016; 397:215-22. [PMID: 26760308 DOI: 10.1515/hsz-2015-0270] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2015] [Accepted: 01/04/2016] [Indexed: 12/12/2022]
Abstract
In postmitotic neurons, the activation of RAS family small GTPases regulates survival, growth and differentiation. Dysregulation of RAS or its major effector pathway, the cascade of RAF-, mitogen-activated and extracellular-signal regulated kinase kinases (MEK), and extracellular-signal regulated kinases (ERK) causes the RASopathies, a group of neurodevelopmental disorders whose pathogenic mechanisms are the subject of intense research. I here summarize the functions of RAS-RAF-MEK-ERK signaling in neurons in vivo, and discuss perspectives for harnessing this pathway to enable novel treatments for nervous system injury, the RASopathies, and possibly other neurological conditions.
Collapse
|
16
|
Ryu HH, Lee YS. Cell type-specific roles of RAS-MAPK signaling in learning and memory: Implications in neurodevelopmental disorders. Neurobiol Learn Mem 2016; 135:13-21. [PMID: 27296701 DOI: 10.1016/j.nlm.2016.06.006] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2016] [Revised: 05/28/2016] [Accepted: 06/09/2016] [Indexed: 01/17/2023]
Abstract
The RAS-mitogen-activated protein kinase (MAPK) signaling pathway plays critical roles in brain function, including learning and memory. Mutations of molecules in the RAS-MAPK pathway are associated with a group of disorders called RASopathies, which include Noonan syndrome, neurofibromatosis type 1, Costello syndrome, Noonan syndrome with multiple lentigines, Legius syndrome, and cardio-facio-cutaneous syndrome. RASopathies share certain clinical symptoms, including craniofacial abnormalities, heart defects, delayed growth, and cognitive deficits such as learning disabilities, while each individual syndrome also displays unique phenotypes. Recent studies using mouse models of RASopathies showed that each disorder may have a distinct molecular and cellular etiology depending on the cellular specificity of the mutated molecules. Here, we review the cell-type specific roles of the regulators of the RAS-MAPK pathway in cognitive function (learning and memory) and their contribution to the development of RASopathies. We also discussed recent technical advances in analyzing cell type-specific transcriptomes and proteomes in the nervous system. Understanding specific mechanisms for these similar but distinct disorders would facilitate the development of mechanism-based individualized treatment for RASopathies.
Collapse
Affiliation(s)
- Hyun-Hee Ryu
- Department of Life Science, College of Natural Science, Chung-Ang University, 84 Heukseok-ro, Dongjak-gu, Seoul 06974, South Korea; Department of Physiology, Seoul National University College of Medicine, Seoul 03080, Republic of Korea
| | - Yong-Seok Lee
- Department of Physiology, Seoul National University College of Medicine, Seoul 03080, Republic of Korea.
| |
Collapse
|