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Dobrigna M, Poëa-Guyon S, Rousseau V, Vincent A, Toutain A, Barnier JV. The molecular basis of p21-activated kinase-associated neurodevelopmental disorders: From genotype to phenotype. Front Neurosci 2023; 17:1123784. [PMID: 36937657 PMCID: PMC10017488 DOI: 10.3389/fnins.2023.1123784] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Accepted: 02/13/2023] [Indexed: 03/06/2023] Open
Abstract
Although the identification of numerous genes involved in neurodevelopmental disorders (NDDs) has reshaped our understanding of their etiology, there are still major obstacles in the way of developing therapeutic solutions for intellectual disability (ID) and other NDDs. These include extensive clinical and genetic heterogeneity, rarity of recurrent pathogenic variants, and comorbidity with other psychiatric traits. Moreover, a large intragenic mutational landscape is at play in some NDDs, leading to a broad range of clinical symptoms. Such diversity of symptoms is due to the different effects DNA variations have on protein functions and their impacts on downstream biological processes. The type of functional alterations, such as loss or gain of function, and interference with signaling pathways, has yet to be correlated with clinical symptoms for most genes. This review aims at discussing our current understanding of how the molecular changes of group I p21-activated kinases (PAK1, 2 and 3), which are essential actors of brain development and function; contribute to a broad clinical spectrum of NDDs. Identifying differences in PAK structure, regulation and spatio-temporal expression may help understanding the specific functions of each group I PAK. Deciphering how each variation type affects these parameters will help uncover the mechanisms underlying mutation pathogenicity. This is a prerequisite for the development of personalized therapeutic approaches.
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Affiliation(s)
- Manon Dobrigna
- Institut des Neurosciences Paris-Saclay, UMR 9197, CNRS, Université Paris-Saclay, Saclay, France
| | - Sandrine Poëa-Guyon
- Institut des Neurosciences Paris-Saclay, UMR 9197, CNRS, Université Paris-Saclay, Saclay, France
| | - Véronique Rousseau
- Institut des Neurosciences Paris-Saclay, UMR 9197, CNRS, Université Paris-Saclay, Saclay, France
| | - Aline Vincent
- Department of Genetics, EA7450 BioTARGen, University Hospital of Caen, Caen, France
| | - Annick Toutain
- Department of Genetics, University Hospital of Tours, UMR 1253, iBrain, Université de Tours, INSERM, Tours, France
| | - Jean-Vianney Barnier
- Institut des Neurosciences Paris-Saclay, UMR 9197, CNRS, Université Paris-Saclay, Saclay, France
- *Correspondence: Jean-Vianney Barnier,
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Scala M, Nishikawa M, Nagata KI, Striano P. Pathophysiological Mechanisms in Neurodevelopmental Disorders Caused by Rac GTPases Dysregulation: What's behind Neuro-RACopathies. Cells 2021; 10:3395. [PMID: 34943902 PMCID: PMC8699292 DOI: 10.3390/cells10123395] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Revised: 11/23/2021] [Accepted: 11/30/2021] [Indexed: 02/07/2023] Open
Abstract
Rho family guanosine triphosphatases (GTPases) regulate cellular signaling and cytoskeletal dynamics, playing a pivotal role in cell adhesion, migration, and cell cycle progression. The Rac subfamily of Rho GTPases consists of three highly homologous proteins, Rac 1-3. The proper function of Rac1 and Rac3, and their correct interaction with guanine nucleotide-exchange factors (GEFs) and GTPase-activating proteins (GAPs) are crucial for neural development. Pathogenic variants affecting these delicate biological processes are implicated in different medical conditions in humans, primarily neurodevelopmental disorders (NDDs). In addition to a direct deleterious effect produced by genetic variants in the RAC genes, a dysregulated GTPase activity resulting from an abnormal function of GEFs and GAPs has been involved in the pathogenesis of distinctive emerging conditions. In this study, we reviewed the current pertinent literature on Rac-related disorders with a primary neurological involvement, providing an overview of the current knowledge on the pathophysiological mechanisms involved in the neuro-RACopathies.
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Affiliation(s)
- Marcello Scala
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, 16132 Genoa, Italy;
- Pediatric Neurology and Muscular Diseases Unit, IRCCS Istituto Giannina Gaslini, 16147 Genoa, Italy
| | - Masashi Nishikawa
- Department of Molecular Neurobiology, Institute for Developmental Research, Aichi Developmental Disability Center, 713-8 Kamiya, Kasugai 480-0392, Japan; (M.N.); (K.-i.N.)
| | - Koh-ichi Nagata
- Department of Molecular Neurobiology, Institute for Developmental Research, Aichi Developmental Disability Center, 713-8 Kamiya, Kasugai 480-0392, Japan; (M.N.); (K.-i.N.)
- Department of Neurochemistry, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Nagoya 466-8550, Japan
| | - Pasquale Striano
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, 16132 Genoa, Italy;
- Pediatric Neurology and Muscular Diseases Unit, IRCCS Istituto Giannina Gaslini, 16147 Genoa, Italy
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Wang Y, Guo F. Group I PAKs in myelin formation and repair of the central nervous system: what, when, and how. Biol Rev Camb Philos Soc 2021; 97:615-639. [PMID: 34811887 DOI: 10.1111/brv.12815] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Revised: 10/20/2021] [Accepted: 11/04/2021] [Indexed: 11/30/2022]
Abstract
p21-activated kinases (PAKs) are a family of cell division control protein 42/ras-related C3 botulinum toxin substrate 1 (Cdc42/Rac1)-activated serine/threonine kinases. Group I PAKs (PAK1-3) have distinct activation mechanisms from group II PAKs (PAK4-6) and are the focus of this review. In transformed cancer cells, PAKs regulate a variety of cellular processes and molecular pathways which are also important for myelin formation and repair in the central nervous system (CNS). De novo mutations in group I PAKs are frequently seen in children with neurodevelopmental defects and white matter anomalies. Group I PAKs regulate virtually every aspect of neuronal development and function. Yet their functions in CNS myelination and remyelination remain incompletely defined. Herein, we highlight the current understanding of PAKs in regulating cellular and molecular pathways and discuss the status of PAK-regulated pathways in oligodendrocyte development. We point out outstanding questions and future directions in the research field of group I PAKs and oligodendrocyte development.
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Affiliation(s)
- Yan Wang
- Department of Neurology, Shriners Hospitals for Children/School of Medicine, Institute for Pediatric Regenerative Medicine (IPRM), University of California, Davis, 2425 Stockton Blvd, Sacramento, CA, 95817, U.S.A
| | - Fuzheng Guo
- Department of Neurology, Shriners Hospitals for Children/School of Medicine, Institute for Pediatric Regenerative Medicine (IPRM), University of California, Davis, 2425 Stockton Blvd, Sacramento, CA, 95817, U.S.A
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Pascolini G, Gaudioso F, Passarelli C, Novelli A, Di Giosaffatte N, Majore S, Grammatico P. Clinical and Molecular Aspects of the Neurodevelopmental Disorder Associated with PAK3 Perturbation. J Mol Neurosci 2021; 71:2474-2481. [PMID: 34227036 DOI: 10.1007/s12031-021-01868-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Accepted: 06/09/2021] [Indexed: 11/27/2022]
Abstract
X-linked intellectual disability can be diagnosed in about 10-12% of intellectually disabled males. In the past, mutations affecting the PAK3 gene (p21 protein-activated kinase 3, MIM#300142) have been associated with a non-syndromic form of X-linked intellectual disability, which has to date been identified in a limited number of families.Since this neurodevelopmental disorder mostly afflicts males, descriptions of symptomatic female carriers are quite rare.We describe a female patient with neurodevelopmental delay and a novel PAK3 variant. Interestingly, she manifests craniofacial anomalies, including microcephaly, representing the second reported microcephalic female but the first for whom a detailed clinical description is available. She also displays other uncommon clinical findings, which we illustrate.Moreover, a comprehensive clinical and molecular review of all to date published patients has been made. This study contributes to further delineate the PAK3-related phenotype, which can be considered a non-syndromic X-linked intellectual disability, with seemingly recurrent craniofacial abnormalities.
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Affiliation(s)
- Giulia Pascolini
- Medical Genetics, Department of Molecular Medicine, Sapienza University, San Camillo-Forlanini Hospital, Circonvallazione Gianicolense 87, 00152, Rome, Italy.
| | - Federica Gaudioso
- Medical Genetics, Department of Molecular Medicine, Sapienza University, San Camillo-Forlanini Hospital, Circonvallazione Gianicolense 87, 00152, Rome, Italy
| | - Chiara Passarelli
- Laboratory of Medical Genetics, Bambino Gesù Children's Hospital, Rome, Italy
| | - Antonio Novelli
- Laboratory of Medical Genetics, Bambino Gesù Children's Hospital, Rome, Italy
| | - Niccolò Di Giosaffatte
- Medical Genetics, Department of Molecular Medicine, Sapienza University, San Camillo-Forlanini Hospital, Circonvallazione Gianicolense 87, 00152, Rome, Italy
| | - Silvia Majore
- Medical Genetics, Department of Molecular Medicine, Sapienza University, San Camillo-Forlanini Hospital, Circonvallazione Gianicolense 87, 00152, Rome, Italy
| | - Paola Grammatico
- Medical Genetics, Department of Molecular Medicine, Sapienza University, San Camillo-Forlanini Hospital, Circonvallazione Gianicolense 87, 00152, Rome, Italy
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Liaci C, Camera M, Caslini G, Rando S, Contino S, Romano V, Merlo GR. Neuronal Cytoskeleton in Intellectual Disability: From Systems Biology and Modeling to Therapeutic Opportunities. Int J Mol Sci 2021; 22:ijms22116167. [PMID: 34200511 PMCID: PMC8201358 DOI: 10.3390/ijms22116167] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Revised: 05/25/2021] [Accepted: 06/04/2021] [Indexed: 02/06/2023] Open
Abstract
Intellectual disability (ID) is a pathological condition characterized by limited intellectual functioning and adaptive behaviors. It affects 1–3% of the worldwide population, and no pharmacological therapies are currently available. More than 1000 genes have been found mutated in ID patients pointing out that, despite the common phenotype, the genetic bases are highly heterogeneous and apparently unrelated. Bibliomic analysis reveals that ID genes converge onto a few biological modules, including cytoskeleton dynamics, whose regulation depends on Rho GTPases transduction. Genetic variants exert their effects at different levels in a hierarchical arrangement, starting from the molecular level and moving toward higher levels of organization, i.e., cell compartment and functions, circuits, cognition, and behavior. Thus, cytoskeleton alterations that have an impact on cell processes such as neuronal migration, neuritogenesis, and synaptic plasticity rebound on the overall establishment of an effective network and consequently on the cognitive phenotype. Systems biology (SB) approaches are more focused on the overall interconnected network rather than on individual genes, thus encouraging the design of therapies that aim to correct common dysregulated biological processes. This review summarizes current knowledge about cytoskeleton control in neurons and its relevance for the ID pathogenesis, exploiting in silico modeling and translating the implications of those findings into biomedical research.
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Affiliation(s)
- Carla Liaci
- Department of Molecular Biotechnology and Health Sciences, University of Torino, Via Nizza 52, 10126 Torino, Italy; (C.L.); (M.C.); (G.C.); (S.R.)
| | - Mattia Camera
- Department of Molecular Biotechnology and Health Sciences, University of Torino, Via Nizza 52, 10126 Torino, Italy; (C.L.); (M.C.); (G.C.); (S.R.)
| | - Giovanni Caslini
- Department of Molecular Biotechnology and Health Sciences, University of Torino, Via Nizza 52, 10126 Torino, Italy; (C.L.); (M.C.); (G.C.); (S.R.)
| | - Simona Rando
- Department of Molecular Biotechnology and Health Sciences, University of Torino, Via Nizza 52, 10126 Torino, Italy; (C.L.); (M.C.); (G.C.); (S.R.)
| | - Salvatore Contino
- Department of Engineering, University of Palermo, Viale delle Scienze Ed. 8, 90128 Palermo, Italy;
| | - Valentino Romano
- Department of Biological, Chemical and Pharmaceutical Sciences and Technologies (STEBICEF), University of Palermo, Viale delle Scienze Ed. 16, 90128 Palermo, Italy;
| | - Giorgio R. Merlo
- Department of Molecular Biotechnology and Health Sciences, University of Torino, Via Nizza 52, 10126 Torino, Italy; (C.L.); (M.C.); (G.C.); (S.R.)
- Correspondence: ; Tel.: +39-0116706449; Fax: +39-0116706432
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Almutairi O, Almutairi HA, Rushood MA. Protein-Activated Kinase 3 (PAK3)-Related Intellectual Disability Associated with Combined Immunodeficiency: A Case Report. AMERICAN JOURNAL OF CASE REPORTS 2021; 22:e930966. [PMID: 34014906 PMCID: PMC8147901 DOI: 10.12659/ajcr.930966] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Revised: 04/14/2021] [Accepted: 03/25/2021] [Indexed: 11/23/2022]
Abstract
BACKGROUND X-linked intellectual disabilities constitute a group of clinically and genetically heterogeneous disorders that are divided into syndromic and nonsyndromic forms. PAK3 mutations are associated with X-linked nonsyndromic forms of intellectual disability, with the most common clinical features being cognitive deficit, large ears, oral motor hypotonia, and neurobehavioral abnormalities. These mutations have been reported to be associated with either loss of the PAK3 protein or loss of its kinase activity. We report a case with the novel PAK3 variant c.685C>T p.(Pro229Ser), which has not been previously described. CASE REPORT We report the first case of a PAK3 mutation to present with the common clinical features along with immunodeficiency resembling common variable immune deficiency. Our patient was a 10-year-old girl who had experienced septic shock with a rapidly deteriorating course when she was 5-years-old. The initial immune work-up showed lymphopenia affecting all cell lines, but preferentially the B-cell compartment. Further work-up of this patient revealed low levels of immunoglobulin (Ig) G, undetectable IgA, reduced IgG1 and IgG2 subclasses, and poor response to the diphtheria/tetanus vaccine. Lymphocyte function, tested as the response to the mitogen phytohemagglutinin, was low and fluctuated between 9% and 22% compared with control samples. The patient experienced recurrent respiratory tract infections, and she responded well to regular intravenous Ig treatment and antibiotic prophylaxis. CONCLUSIONS The current case might provide a new insight into PAK3 gene function. Although further evidence is needed, it is worth considering that immunological abnormalities may be associated with PAK3 gene mutations.
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Affiliation(s)
| | | | - Maysoun Al Rushood
- Department of Pediatrics, Faculty of Medicine, Health Sciences Center, Kuwait University, Jabriya, Kuwait
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Yang J, Yang X, Tang K. Interneuron development and dysfunction. FEBS J 2021; 289:2318-2336. [PMID: 33844440 DOI: 10.1111/febs.15872] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Accepted: 04/09/2021] [Indexed: 12/17/2022]
Abstract
Understanding excitation and inhibition balance in the brain begins with the tale of two basic types of neurons, glutamatergic projection neurons and GABAergic interneurons. The diversity of cortical interneurons is contributed by multiple origins in the ventral forebrain, various tangential migration routes, and complicated regulations of intrinsic factors, extrinsic signals, and activities. Abnormalities of interneuron development lead to dysfunction of interneurons and inhibitory circuits, which are highly associated with neurodevelopmental disorders including schizophrenia, autism spectrum disorders, and intellectual disability. In this review, we mainly discuss recent findings on the development of cortical interneuron and on neurodevelopmental disorders related to interneuron dysfunction.
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Affiliation(s)
- Jiaxin Yang
- Precise Genome Engineering Center, School of Life Sciences, Guangzhou University, China
| | - Xiong Yang
- Precise Genome Engineering Center, School of Life Sciences, Guangzhou University, China
| | - Ke Tang
- Precise Genome Engineering Center, School of Life Sciences, Guangzhou University, China
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Zhang K, Wang Y, Fan T, Zeng C, Sun ZS. The p21-activated kinases in neural cytoskeletal remodeling and related neurological disorders. Protein Cell 2020; 13:6-25. [PMID: 33306168 PMCID: PMC8776968 DOI: 10.1007/s13238-020-00812-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Accepted: 11/19/2020] [Indexed: 12/15/2022] Open
Abstract
The serine/threonine p21-activated kinases (PAKs), as main effectors of the Rho GTPases Cdc42 and Rac, represent a group of important molecular switches linking the complex cytoskeletal networks to broad neural activity. PAKs show wide expression in the brain, but they differ in specific cell types, brain regions, and developmental stages. PAKs play an essential and differential role in controlling neural cytoskeletal remodeling and are related to the development and fate of neurons as well as the structural and functional plasticity of dendritic spines. PAK-mediated actin signaling and interacting functional networks represent a common pathway frequently affected in multiple neurodevelopmental and neurodegenerative disorders. Considering specific small-molecule agonists and inhibitors for PAKs have been developed in cancer treatment, comprehensive knowledge about the role of PAKs in neural cytoskeletal remodeling will promote our understanding of the complex mechanisms underlying neurological diseases, which may also represent potential therapeutic targets of these diseases.
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Affiliation(s)
- Kaifan Zhang
- Beijing Institutes of Life Science, Chinese Academy of Sciences, Beijing, 100101, China.,Institute of Genomic Medicine, Wenzhou Medical University, Wenzhou, 325000, China
| | - Yan Wang
- Beijing Institutes of Life Science, Chinese Academy of Sciences, Beijing, 100101, China.
| | - Tianda Fan
- Institute of Genomic Medicine, Wenzhou Medical University, Wenzhou, 325000, China
| | - Cheng Zeng
- Beijing Institutes of Life Science, Chinese Academy of Sciences, Beijing, 100101, China.,CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Zhong Sheng Sun
- Beijing Institutes of Life Science, Chinese Academy of Sciences, Beijing, 100101, China. .,Institute of Genomic Medicine, Wenzhou Medical University, Wenzhou, 325000, China. .,CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, 100049, China. .,State Key Laboratory of Integrated Management of Pest Insects and Rodents, Chinese Academy of Sciences, Beijing, 100101, China.
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Qian Y, Wu B, Lu Y, Zhou W, Wang S, Wang H. Novel PAK3 gene missense variant associated with two Chinese siblings with intellectual disability: a case report. BMC MEDICAL GENETICS 2020; 21:31. [PMID: 32050918 PMCID: PMC7017536 DOI: 10.1186/s12881-020-0957-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Accepted: 01/21/2020] [Indexed: 01/23/2023]
Abstract
BACKGROUND Intellectual disability (ID) constitutes the most common group of neurodevelopmental disorders. Exome sequencing has enabled the discovery of genetic mutations responsible for a wide range of ID disorders. CASE PRESENTATION In this study, we reported on two male siblings, aged 4 and 2 years, with motor and mental developmental delays and mild dysmorphic facial features. To identify the genetic causes of these symptoms, we employed trio-whole exome sequencing for the proband. We found a novel hemizygous missense variant in the PAK3 gene (c.1112G > A, p.Cys371Tyr), which encodes the p21-activated kinase 3, in the proband, which inherited from mother. The younger brother also has the hemizygous variant, which was confirmed by Sanger sequencing. The variant is located in the kinase domain and was regarded as a likely pathogenic variant in this family. CONCLUSION We diagnosed two male siblings with developmental delays as having a PAK3 likely pathogenic variant. This finding expands the list of PAK3 gene mutations associated with neurodevelopmental disorders and provides further details on its clinical features.
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Affiliation(s)
- Yanyan Qian
- Center for Molecular Medicine, Children's Hospital of Fudan University, Shanghai Key Laboratory of Birth Defects, Shanghai, 201102, China
| | - Bingbing Wu
- Center for Molecular Medicine, Children's Hospital of Fudan University, Shanghai Key Laboratory of Birth Defects, Shanghai, 201102, China
| | - Yulan Lu
- Center for Molecular Medicine, Children's Hospital of Fudan University, Shanghai Key Laboratory of Birth Defects, Shanghai, 201102, China
| | - Wenhao Zhou
- Center for Molecular Medicine, Children's Hospital of Fudan University, Shanghai Key Laboratory of Birth Defects, Shanghai, 201102, China
| | - Sujuan Wang
- Departments of Rehabilitation, Children's Hospital of Fudan University, Shanghai, 201102, China.
| | - Huijun Wang
- Center for Molecular Medicine, Children's Hospital of Fudan University, Shanghai Key Laboratory of Birth Defects, Shanghai, 201102, China. .,Pediatrics Research Institute, Children's Hospital of Fudan University, 399 Wanyuan Road, Shanghai, 201102, China.
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Duarte K, Heide S, Poëa-Guyon S, Rousseau V, Depienne C, Rastetter A, Nava C, Attié-Bitach T, Razavi F, Martinovic J, Moutard ML, Cherfils J, Mignot C, Héron D, Barnier JV. PAK3 mutations responsible for severe intellectual disability and callosal agenesis inhibit cell migration. Neurobiol Dis 2019; 136:104709. [PMID: 31843706 DOI: 10.1016/j.nbd.2019.104709] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2019] [Revised: 11/13/2019] [Accepted: 12/08/2019] [Indexed: 01/12/2023] Open
Abstract
Corpus callosum agenesis (CCA) is a brain malformation associated with a wide clinical spectrum including intellectual disability (ID) and an etiopathological complexity. We identified a novel missense G424R mutation in the X-linked p21-activated kinase 3 (PAK3) gene in a boy presenting with severe ID, microcephaly and CCA and his fetal sibling with CCA and severe hydrocephaly. PAK3 kinase is known to control synaptic plasticity and dendritic spine dynamics but its implication is less characterized in brain ontogenesis. In order to identify developmental functions of PAK3 impacted by mutations responsible for CCA, we compared the biochemical and biological effects of three PAK3 mutations localized in the catalytic domain. These mutations include two "severe" G424R and K389N variants (responsible for severe ID and CCA) and the "mild" A365E variant (responsible for nonsyndromic mild ID). Whereas they suppressed kinase activity, only the two severe variants displayed normal protein stability. Furthermore, they increased interactions between PAK3 and the guanine exchange factor αPIX/ARHGEF6, disturbed adhesion point dynamics and cell spreading, and severely impacted cell migration. Our findings highlight new molecular defects associated with mutations responsible for severe clinical phenotypes with developmental brain defects.
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Affiliation(s)
- Kévin Duarte
- Department of Cognition and Behavior, Paris-Saclay Institute of Neuroscience (Neuro-PSI CNRS, UMR 9197), Paris-Sud and Paris-Saclay Universities, Orsay, France.
| | - Solveig Heide
- Department of genetics, Reference Center for Intellectual Disabilities of Rare Causes, APHP, GH Pitié Salpêtrière, Paris, France.
| | - Sandrine Poëa-Guyon
- Department of Cognition and Behavior, Paris-Saclay Institute of Neuroscience (Neuro-PSI CNRS, UMR 9197), Paris-Sud and Paris-Saclay Universities, Orsay, France.
| | - Véronique Rousseau
- Department of Cognition and Behavior, Paris-Saclay Institute of Neuroscience (Neuro-PSI CNRS, UMR 9197), Paris-Sud and Paris-Saclay Universities, Orsay, France.
| | - Christel Depienne
- Department of genetics, Reference Center for Intellectual Disabilities of Rare Causes, APHP, GH Pitié Salpêtrière, Paris, France; Institute of Human Genetics, University Hospital Essen, University of Duisburg-Essen, Essen, Germany.
| | - Agnès Rastetter
- Department of genetics, Reference Center for Intellectual Disabilities of Rare Causes, APHP, GH Pitié Salpêtrière, Paris, France.
| | - Caroline Nava
- Department of genetics, Reference Center for Intellectual Disabilities of Rare Causes, APHP, GH Pitié Salpêtrière, Paris, France.
| | - Tania Attié-Bitach
- Unité d'Embryofoetopathologie, Service of Histology-Embryology-Cytogenetics, APHP Necker Enfants Malades & Imagine Institute, Inserm U1163, Paris, France.
| | - Ferechté Razavi
- Unité d'Embryofoetopathologie, Service of Histology-Embryology-Cytogenetics, APHP Necker Enfants Malades & Imagine Institute, Inserm U1163, Paris, France
| | | | - Marie Laure Moutard
- Department of Pediatrics Neurology, Reference Center for Intellectual Disabilities of Rare Causes APHP, Armand-Trousseau Hospital, Paris, France.
| | - Jacqueline Cherfils
- Laboratoire de Biologie et Pharmacologie Appliquée, CNRS and Ecole normale supérieure Paris-Saclay, Cachan, France.
| | - Cyril Mignot
- Department of genetics, Reference Center for Intellectual Disabilities of Rare Causes, APHP, GH Pitié Salpêtrière, Paris, France.
| | - Delphine Héron
- Department of genetics, Reference Center for Intellectual Disabilities of Rare Causes, APHP, GH Pitié Salpêtrière, Paris, France.
| | - Jean-Vianney Barnier
- Department of Cognition and Behavior, Paris-Saclay Institute of Neuroscience (Neuro-PSI CNRS, UMR 9197), Paris-Sud and Paris-Saclay Universities, Orsay, France.
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Further delineation of the phenotype of PAK3-associated x-linked intellectual disability: Identification of a novel missense mutation and review of literature. Eur J Med Genet 2019; 63:103800. [PMID: 31678216 DOI: 10.1016/j.ejmg.2019.103800] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2019] [Revised: 10/08/2019] [Accepted: 10/26/2019] [Indexed: 10/25/2022]
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p21-Activated kinase 3 promotes cancer stem cell phenotypes through activating the Akt-GSK3β-β-catenin signaling pathway in pancreatic cancer cells. Cancer Lett 2019; 456:13-22. [DOI: 10.1016/j.canlet.2019.04.026] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2019] [Revised: 04/18/2019] [Accepted: 04/25/2019] [Indexed: 12/18/2022]
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13
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Solution structures and biophysical analysis of full-length group A PAKs reveal they are monomeric and auto-inhibited in cis. Biochem J 2019; 476:1037-1051. [PMID: 30858169 PMCID: PMC6448136 DOI: 10.1042/bcj20180867] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2018] [Revised: 03/05/2019] [Accepted: 03/08/2019] [Indexed: 12/13/2022]
Abstract
The group A p21-activated kinases (PAKs) exist in an auto-inhibited form until activated by GTPase binding and auto-phosphorylation. In the auto-inhibited form, a regulatory domain binds to the kinase domain (KD) blocking the binding of substrates, and CDC42 or Rac binding to the regulatory domain relieves this auto-inhibition allowing auto-phosphorylation on the KD activation loop. We have determined the crystal structure of the PAK3 catalytic domain and by small angle X-ray scattering, the solution-phase structures of full-length inactive PAK1 and PAK3. The structures reveal a compact but elongated molecular shape that demonstrates that, together with multiple independent biophysical measurements and in contrast with previous assumptions, group A PAKs are monomeric both before and after activation, consistent with an activation mechanism of cis-auto-inhibition and initial cis-auto-phosphorylation, followed by transient dimerisation to allow trans-auto-phosphorylation for full activation, yielding a monomeric active PAK protein.
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Rho GTPases in Intellectual Disability: From Genetics to Therapeutic Opportunities. Int J Mol Sci 2018; 19:ijms19061821. [PMID: 29925821 PMCID: PMC6032284 DOI: 10.3390/ijms19061821] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2018] [Revised: 06/14/2018] [Accepted: 06/16/2018] [Indexed: 12/22/2022] Open
Abstract
Rho-class small GTPases are implicated in basic cellular processes at nearly all brain developmental steps, from neurogenesis and migration to axon guidance and synaptic plasticity. GTPases are key signal transducing enzymes that link extracellular cues to the neuronal responses required for the construction of neuronal networks, as well as for synaptic function and plasticity. Rho GTPases are highly regulated by a complex set of activating (GEFs) and inactivating (GAPs) partners, via protein:protein interactions (PPI). Misregulated RhoA, Rac1/Rac3 and cdc42 activity has been linked with intellectual disability (ID) and other neurodevelopmental conditions that comprise ID. All genetic evidences indicate that in these disorders the RhoA pathway is hyperactive while the Rac1 and cdc42 pathways are consistently hypoactive. Adopting cultured neurons for in vitro testing and specific animal models of ID for in vivo examination, the endophenotypes associated with these conditions are emerging and include altered neuronal networking, unbalanced excitation/inhibition and altered synaptic activity and plasticity. As we approach a clearer definition of these phenotype(s) and the role of hyper- and hypo-active GTPases in the construction of neuronal networks, there is an increasing possibility that selective inhibitors and activators might be designed via PPI, or identified by screening, that counteract the misregulation of small GTPases and result in alleviation of the cognitive condition. Here we review all knowledge in support of this possibility.
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15
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Horvath GA, Tarailo-Graovac M, Bartel T, Race S, Van Allen MI, Blydt-Hansen I, Ross CJ, Wasserman WW, Connolly MB, van Karnebeek CDM. Improvement of Self-Injury With Dopamine and Serotonin Replacement Therapy in a Patient With a Hemizygous PAK3 Mutation: A New Therapeutic Strategy for Neuropsychiatric Features of an Intellectual Disability Syndrome. J Child Neurol 2018; 33:106-113. [PMID: 29246092 DOI: 10.1177/0883073817740443] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
PAK3-related intellectual disability is caused by mutations in the gene encoding the p21-activated kinase (PAK) protein. It is characterized by mild to moderate cognitive impairment, micro/normocephaly, and a neurobehavioral phenotype characterized by short attention span, anxiety, restlessness, aggression, and self-abusive behaviors. The authors report a patient with a novel PAK3 mutation, who presented with intellectual disability, severe automutilation, and epilepsy. His magnetic resonance imaging changes were most likely secondary to lacerations from parenchymal contusions. His behavior was difficult to manage with behavior interventions or multiple medications. After finding low levels of dopamine and borderline low serotonin metabolites in the spinal fluid, treatment with low dose L-dopa/carbidopa and 5-hydroxytryptophan significantly improved his self-injurious behavior. This is the first case of PAK3-related intellectual disability presenting with severe self-injury with improvement following treatment. The patient's response to neurotransmitter replacement therapy raises the question if this treatment intervention might help other individuals suffering genetic syndromes and self-injurious behaviors.
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Affiliation(s)
- Gabriella A Horvath
- 1 Division of Biochemical Diseases, Department of Pediatrics, University of British Columbia, BC Children's Hospital, Vancouver, British Columbia, Canada.,2 BC Children's Hospital Research Institute, Vancouver, British Columbia, Canada
| | - Maja Tarailo-Graovac
- 3 Department of Pediatrics, Centre for Molecular Medicine and Therapeutics, University of British Columbia, Vancouver, British Columbia, Canada
| | - Tanja Bartel
- 4 Mission Senior Secondary School, Mission, British Columbia, Canada
| | - Simone Race
- 1 Division of Biochemical Diseases, Department of Pediatrics, University of British Columbia, BC Children's Hospital, Vancouver, British Columbia, Canada
| | - Margot I Van Allen
- 2 BC Children's Hospital Research Institute, Vancouver, British Columbia, Canada.,5 Department of Medical Genetics, University of British Columbia, BC Children's and Women's Hospital, Vancouver, British Columbia, Canada
| | - Ingrid Blydt-Hansen
- 2 BC Children's Hospital Research Institute, Vancouver, British Columbia, Canada.,6 Queens University, Kingston, Ontario, Canada
| | - Colin J Ross
- 2 BC Children's Hospital Research Institute, Vancouver, British Columbia, Canada.,7 Faculty of Pharmaceutical Sciences, University of British Columbia, Vancouver, British Columbia, Canada
| | - Wyeth W Wasserman
- 2 BC Children's Hospital Research Institute, Vancouver, British Columbia, Canada.,3 Department of Pediatrics, Centre for Molecular Medicine and Therapeutics, University of British Columbia, Vancouver, British Columbia, Canada
| | - Mary B Connolly
- 8 Division of Pediatric Neurology, Department of Pediatrics, University of British Columbia, BC Children's Hospital, Vancouver, British Columbia, Canada
| | - Clara D M van Karnebeek
- 2 BC Children's Hospital Research Institute, Vancouver, British Columbia, Canada.,3 Department of Pediatrics, Centre for Molecular Medicine and Therapeutics, University of British Columbia, Vancouver, British Columbia, Canada
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16
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Krivinko JM, Erickson SL, Abrahamson EE, Wills ZP, Ikonomovic MD, Penzes P, Sweet RA. Kalirin reduction rescues psychosis-associated behavioral deficits in APPswe/PSEN1dE9 transgenic mice. Neurobiol Aging 2017; 54:59-70. [PMID: 28319837 PMCID: PMC5502748 DOI: 10.1016/j.neurobiolaging.2017.02.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2016] [Revised: 01/18/2017] [Accepted: 02/09/2017] [Indexed: 12/17/2022]
Abstract
Psychosis in Alzheimer's disease (AD+P) represents a distinct clinical and neurobiological AD phenotype and is associated with more rapid cognitive decline, higher rates of abnormal behaviors, and increased caregiver burden compared with AD without psychosis. On a molecular level, AD+P is associated with greater reductions in the protein kalirin, a guanine exchange factor which has also been linked to the psychotic disease, schizophrenia. In this study, we sought to determine the molecular and behavioral consequences of kalirin reduction in APPswe/PSEN1dE9 mice. We evaluated mice with and without kalirin reduction during tasks measuring psychosis-associated behaviors and spatial memory. We found that kalirin reduction in APPswe/PSEN1dE9 mice significantly attenuated psychosis-associated behavior at 12 months of age without changing spatial memory performance. The 12-month-old APPswe/PSEN1dE9 mice with reduced kalirin levels also had increased levels of the active, phosphorylated forms of p21 protein (Cdc42/Rac)-activated kinases (PAKs), which function in signaling pathways for maintenance of dendritic spine density, morphology, and function.
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Affiliation(s)
- Josh M Krivinko
- Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Susan L Erickson
- Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Eric E Abrahamson
- Department of Neurology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Zachary P Wills
- Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Milos D Ikonomovic
- Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA; Department of Neurology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA; Geriatric Research, Education, and Clinical Center, VA Pittsburgh Healthcare System, Pittsburgh, PA, USA
| | - Peter Penzes
- Department of Physiology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA; Department of Psychiatry and Behavioral Sciences, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - Robert A Sweet
- Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA; Department of Neurology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA; Mental Illness Research, Education, and Clinical Center, VA Pittsburgh Healthcare System, Pittsburgh, PA, USA.
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Functional analysis of rare variants found in schizophrenia implicates a critical role for GIT1-PAK3 signaling in neuroplasticity. Mol Psychiatry 2017; 22:417-429. [PMID: 27457813 PMCID: PMC6186433 DOI: 10.1038/mp.2016.98] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/27/2016] [Revised: 03/21/2016] [Accepted: 05/02/2016] [Indexed: 01/21/2023]
Abstract
Although the pathogenesis of schizophrenia (SCZ) is proposed to involve alterations of neural circuits via synaptic dysfunction, the underlying molecular mechanisms remain poorly understood. Recent exome sequencing studies of SCZ have uncovered numerous single-nucleotide variants (SNVs); however, the majority of these SNVs have unknown functional consequences, leaving their disease relevance uncertain. Filling this knowledge gap requires systematic application of quantitative and scalable assays to assess known and novel biological functions of genes. Here we demonstrate loss-of-function effects of multiple rare coding SNVs found in SCZ subjects in the GIT1 (G protein-coupled receptor kinase interacting ArfGAP 1) gene using functional cell-based assays involving coexpression of GIT1 and PAK3 (p21 protein (Cdc42/Rac)-activated kinase 3). Most notably, a GIT1-R283W variant reported in four independent SCZ cases was defective in activating PAK3 as well as MAPK (mitogen-activated protein kinase). Similar functional deficits were found for a de novo SCZ variant GIT1-S601N. Additional assays revealed deficits in the capacity of GIT1-R283W to stimulate PAK phosphorylation in cultured hippocampal neurons. In addition, GIT1-R283W showed deficits in the induction of GAD1 (glutamate decarboxylase 1) protein expression. Extending these functional assays to 10 additional rare GIT1 variants revealed the existence of an allelic series with the majority of the SCZ case variants exhibiting loss of function toward MAPK activation in a manner correlated with loss of PAK3 activation. Taken together, we propose that rare variants in GIT1, along with other genetic and environmental factors, cause dysregulation of PAK3 leading to synaptic deficits in SCZ.
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18
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Short case report: Xq23 deletion involving PAK3 as a novel cause of developmental delay in a 6-year-old boy. Clin Dysmorphol 2017; 26:38-40. [PMID: 27753653 DOI: 10.1097/mcd.0000000000000154] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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19
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Hertecant J, Komara M, Nagi A, Al-Zaabi O, Fathallah W, Cui H, Yang Y, Eng CM, Al Sorkhy M, Ghattas MA, Al-Gazali L, Ali BR. A de novo mutation in the X-linked PAK3 gene is the underlying cause of intellectual disability and macrocephaly in monozygotic twins. Eur J Med Genet 2017; 60:212-216. [PMID: 28126652 DOI: 10.1016/j.ejmg.2017.01.004] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2016] [Revised: 01/17/2017] [Accepted: 01/18/2017] [Indexed: 02/08/2023]
Abstract
Pathogenic variants in theP21 protein (Cdc42/Rac)-activated kinase 3gene (PAK3) lead to a rare non syndromic X-linked intellectual disability. The protein encoded by this gene forms an activated complex with GTP-bound RAS-like (P21), CDC2 and RAC1 proteins which then mediates a variety of cellular processes. So far, mutations in PAK3 gene have been reported in few families affected with intellectual disability associated with neurological manifestations such as speech defect, behavioral problem, brain structural abnormalities, microcephaly and cerebral palsy. In this study whole exome sequencing revealed a de novo likely pathogenic variant in PAK3 gene in monozygotic twins presented with intellectual disability, speech delay, behavioral problems and macrocephaly. Macrocephaly was noticed in our patients from birth at 35 weeks of gestation. This aspect of the phenotype has not been previously reported in other documented cases with pathogenic mutations in PAK3 gene. Our findings extend the phenotype of this disorder to include macrocephaly and offers further clues to the importance of the serine/threonine-protein kinase 3 (PAK3) protein in brain development and function.
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Affiliation(s)
- Jozef Hertecant
- Department of Paediatrics, Tawam Hospital, Al-Ain, United Arab Emirates; Department of Paediatrics, College of Medicine and Health Sciences, United Arab Emirates University, Al-Ain, United Arab Emirates
| | - Makanko Komara
- Department of Pathology, College of Medicine and Health Sciences, United Arab Emirates University, Al-Ain, United Arab Emirates
| | - Aslam Nagi
- Department of Paediatrics, Tawam Hospital, Al-Ain, United Arab Emirates
| | | | | | - Hong Cui
- Department of Molecular and Human Genetics, Baylor College of Medicine, Baylor Miraca Genetics Laboratories, Houston, TX 77030, USA
| | - Yaping Yang
- Department of Molecular and Human Genetics, Baylor College of Medicine, Baylor Miraca Genetics Laboratories, Houston, TX 77030, USA
| | - Christine M Eng
- Department of Molecular and Human Genetics, Baylor College of Medicine, Baylor Miraca Genetics Laboratories, Houston, TX 77030, USA
| | - Mohammad Al Sorkhy
- College of Pharmacy, Al Ain University of Science and Technology, Al-Ain, United Arab Emirates
| | - Mohammad A Ghattas
- College of Pharmacy, Al Ain University of Science and Technology, Al-Ain, United Arab Emirates
| | - Lihadh Al-Gazali
- Department of Paediatrics, College of Medicine and Health Sciences, United Arab Emirates University, Al-Ain, United Arab Emirates
| | - Bassam R Ali
- Department of Pathology, College of Medicine and Health Sciences, United Arab Emirates University, Al-Ain, United Arab Emirates.
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20
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Maglorius Renkilaraj MRL, Baudouin L, Wells CM, Doulazmi M, Wehrlé R, Cannaya V, Bachelin C, Barnier JV, Jia Z, Nait Oumesmar B, Dusart I, Bouslama-Oueghlani L. The intellectual disability protein PAK3 regulates oligodendrocyte precursor cell differentiation. Neurobiol Dis 2016; 98:137-148. [PMID: 27940202 DOI: 10.1016/j.nbd.2016.12.004] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Revised: 11/04/2016] [Accepted: 12/02/2016] [Indexed: 10/20/2022] Open
Abstract
Oligodendrocyte and myelin deficits have been reported in mental/psychiatric diseases. The p21-activated kinase 3 (PAK3), a serine/threonine kinase, whose activity is stimulated by the binding of active Rac and Cdc42 GTPases is affected in these pathologies. Indeed, many mutations of Pak3 gene have been described in non-syndromic intellectual disability diseases. Pak3 is expressed mainly in the brain where its role has been investigated in neurons but not in glial cells. Here, we showed that PAK3 is highly expressed in oligodendrocyte precursors (OPCs) and its expression decreases in mature oligodendrocytes. In the developing white matter of the Pak3 knockout mice, we found defects of oligodendrocyte differentiation in the corpus callosum and to a lesser extent in the anterior commissure, which were compensated at the adult stage. In vitro experiments in OPC cultures, derived from Pak3 knockout and wild type brains, support a developmental and cell-autonomous role for PAK3 in regulating OPC differentiation into mature oligodendrocytes. Moreover, we did not detect any obvious alterations of the proliferation or migration of Pak3 null OPCs compared to wild type. Overall, our data highlight PAK3 as a new regulator of OPC differentiation.
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Affiliation(s)
| | - Lucas Baudouin
- Sorbonne Universités, UPMC Univ Paris 06, INSERM U 1127, CNRS UMR 7225, Institut du Cerveau et de la Moelle épinière, F-75013 Paris, France
| | | | - Mohamed Doulazmi
- Sorbonne Universités, UPMC Univ Paris 06, INSERM, CNRS, Institut de Biologie Paris Seine, Adaptation Biologique et vieillissement, F-75005 Paris, France
| | - Rosine Wehrlé
- Sorbonne Universités, UPMC Univ Paris 06, INSERM, CNRS, Institut de Biologie Paris Seine, Neuroscience Paris Seine, F-75005 Paris, France
| | - Vidjeacoumary Cannaya
- Sorbonne Universités, UPMC Univ Paris 06, INSERM, CNRS, Institut de Biologie Paris Seine, Neuroscience Paris Seine, F-75005 Paris, France
| | - Corinne Bachelin
- Sorbonne Universités, UPMC Univ Paris 06, INSERM U 1127, CNRS UMR 7225, Institut du Cerveau et de la Moelle épinière, F-75013 Paris, France
| | - Jean-Vianney Barnier
- Institute of Neuroscience Paris-Saclay, CNRS-Université Paris-Sud, UMR9197, F-91405 Orsay, France
| | - Zhengping Jia
- Neurosciences & Mental Health, The Hospital for Sick Children, and Department of Physiology, Faculty of Medicine, University of Toronto, 555 University, Toronto, Ontario M5G 1X8, Canada
| | - Brahim Nait Oumesmar
- Sorbonne Universités, UPMC Univ Paris 06, INSERM U 1127, CNRS UMR 7225, Institut du Cerveau et de la Moelle épinière, F-75013 Paris, France
| | - Isabelle Dusart
- Sorbonne Universités, UPMC Univ Paris 06, INSERM, CNRS, Institut de Biologie Paris Seine, Neuroscience Paris Seine, F-75005 Paris, France
| | - Lamia Bouslama-Oueghlani
- Sorbonne Universités, UPMC Univ Paris 06, INSERM, CNRS, Institut de Biologie Paris Seine, Neuroscience Paris Seine, F-75005 Paris, France; Sorbonne Universités, UPMC Univ Paris 06, INSERM U 1127, CNRS UMR 7225, Institut du Cerveau et de la Moelle épinière, F-75013 Paris, France.
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21
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Jin Z, Yu L, Geng J, Wang J, Jin X, Huang H. A novel 47.2Mb duplication on chromosomal bands Xq21.1–25 associated with mental retardation. Gene 2015; 567:98-102. [DOI: 10.1016/j.gene.2015.04.083] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Revised: 04/20/2015] [Accepted: 04/22/2015] [Indexed: 11/24/2022]
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22
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Magini P, Pippucci T, Tsai IC, Coppola S, Stellacci E, Bartoletti-Stella A, Turchetti D, Graziano C, Cenacchi G, Neri I, Cordelli DM, Marchiani V, Bergamaschi R, Gasparre G, Neri G, Mazzanti L, Patrizi A, Franzoni E, Romeo G, Bordo D, Tartaglia M, Katsanis N, Seri M. A mutation in PAK3 with a dual molecular effect deregulates the RAS/MAPK pathway and drives an X-linked syndromic phenotype. Hum Mol Genet 2014; 23:3607-17. [PMID: 24556213 DOI: 10.1093/hmg/ddu070] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Loss-of-function mutations in PAK3 contribute to non-syndromic X-linked intellectual disability (NS-XLID) by affecting dendritic spine density and morphology. Linkage analysis in a three-generation family with affected males showing ID, agenesis of corpus callosum, cerebellar hypoplasia, microcephaly and ichthyosis, revealed a candidate disease locus in Xq21.33q24 encompassing over 280 genes. Subsequent to sequencing all coding exons of the X chromosome, we identified a single novel variant within the linkage region, affecting a conserved codon of PAK3. Biochemical studies showed that, similar to previous NS-XLID-associated lesions, the predicted amino acid substitution (Lys389Asn) abolished the kinase activity of PAK3. In addition, the introduced residue conferred a dominant-negative function to the protein that drives the syndromic phenotype. Using a combination of in vitro and in vivo studies in zebrafish embryos, we show that PAK3(N389) escapes its physiologic degradation and is able to perturb MAPK signaling via an uncontrolled kinase-independent function, which in turn leads to alterations of cerebral and craniofacial structures in vivo. Our data expand the spectrum of phenotypes associated with PAK3 mutations, characterize a novel mechanism resulting in a dual molecular effect of the same mutation with a complex PAK3 functional deregulation and provide evidence for a direct functional impact of aberrant PAK3 function on MAPK signaling.
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Affiliation(s)
- Pamela Magini
- U.O. Genetica Medica, Dipartimento di Scienze Mediche e Chirurgiche (DIMEC)
| | - Tommaso Pippucci
- U.O. Genetica Medica, Dipartimento di Scienze Mediche e Chirurgiche (DIMEC)
| | - I-Chun Tsai
- Center for Human Disease Modeling, Duke University Medical Center, Durham 27710, USA
| | - Simona Coppola
- Centro Nazionale per le Malattie Rare, Dipartimento di Ematologia, Oncologia e Medicina Molecolare, Istituto Superiore di Sanità, Roma 00161, Italy
| | - Emilia Stellacci
- Dipartimento di Ematologia, Oncologia e Medicina Molecolare, Istituto Superiore di Sanità, Roma 00161, Italy
| | - Anna Bartoletti-Stella
- Laboratorio di Neuropatologia, Dipartimento di Scienze Biomediche e Neuromotorie (DIBINEM)
| | - Daniela Turchetti
- U.O. Genetica Medica, Dipartimento di Scienze Mediche e Chirurgiche (DIMEC)
| | - Claudio Graziano
- U.O. Genetica Medica, Dipartimento di Scienze Mediche e Chirurgiche (DIMEC)
| | - Giovanna Cenacchi
- U.O. Anatomia e Istologia Patologica, Dipartimento di Scienze Biomediche e Neuromotorie (DIBINEM)
| | - Iria Neri
- U.O. Dermatologia, Dipartimento di Medicina Specialistica, Diagnostica e Sperimentale (DIMES)
| | - Duccio Maria Cordelli
- U.O. Neuropsichiatria Infantile, Dipartimento di Scienze Mediche e Chirurgiche (DIMEC) and
| | - Valentina Marchiani
- U.O. Neuropsichiatria Infantile, Dipartimento di Scienze Mediche e Chirurgiche (DIMEC) and
| | - Rosalba Bergamaschi
- Pediatria d'Urgenza, Dipartimento di Scienze Mediche e Chirurgiche (DIMEC), Università di Bologna, Bologna 40138, Italy
| | - Giuseppe Gasparre
- U.O. Genetica Medica, Dipartimento di Scienze Mediche e Chirurgiche (DIMEC)
| | - Giovanni Neri
- Istituto di Genetica Medica, Università Cattolica del Sacro Cuore, Roma 00168, Italy
| | - Laura Mazzanti
- S.S. Malattie Rare e Sindromologia, Dipartimento di Scienze Mediche e Chirurgiche (DIMEC), Università di Bologna, Policlinico S.Orsola-Malpighi, Bologna 40138, Italy
| | - Annalisa Patrizi
- U.O. Dermatologia, Dipartimento di Medicina Specialistica, Diagnostica e Sperimentale (DIMES)
| | - Emilio Franzoni
- U.O. Neuropsichiatria Infantile, Dipartimento di Scienze Mediche e Chirurgiche (DIMEC) and
| | - Giovanni Romeo
- U.O. Genetica Medica, Dipartimento di Scienze Mediche e Chirurgiche (DIMEC)
| | - Domenico Bordo
- IRCCS AOU S. Martino - IST, Istituto Nazionale per la Ricerca sul Cancro, Genova, Italy
| | - Marco Tartaglia
- Dipartimento di Ematologia, Oncologia e Medicina Molecolare, Istituto Superiore di Sanità, Roma 00161, Italy
| | - Nicholas Katsanis
- Center for Human Disease Modeling, Duke University Medical Center, Durham 27710, USA
| | - Marco Seri
- U.O. Genetica Medica, Dipartimento di Scienze Mediche e Chirurgiche (DIMEC),
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23
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Ke Y, Lei M, Wang X, Solaro RJ. Unique catalytic activities and scaffolding of p21 activated kinase-1 in cardiovascular signaling. Front Pharmacol 2013; 4:116. [PMID: 24098283 PMCID: PMC3784770 DOI: 10.3389/fphar.2013.00116] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2013] [Accepted: 08/28/2013] [Indexed: 01/16/2023] Open
Abstract
P21 activated kinase-1 (Pak1) has diverse functions in mammalian cells. Although a large number of phosphoproteins have been designated as Pak1 substrates from in vitro studies, emerging evidence has indicated that Pak1 may function as a signaling molecule through a unique molecular mechanism – scaffolding. By scaffolding, Pak1 delivers signals through an auto-phosphorylation-induced conformational change without transfer of a phosphate group to its immediate downstream effector(s). Here we review evidence for this regulatory mechanism based on structural and functional studies of Pak1 in different cell types and research models as well as in vitro biochemical assays. We also discuss the implications of Pak1 scaffolding in disease-related signaling processes and the potential in cardiovascular drug development.
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Affiliation(s)
- Yunbo Ke
- Department of Physiology and Biophysics, University of Illinois at Chicago Chicago, IL, USA ; Center for Cardiovascular Research, College of Medicine, University of Illinois at Chicago Chicago, IL, USA
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24
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Ba W, van der Raadt J, Nadif Kasri N. Rho GTPase signaling at the synapse: implications for intellectual disability. Exp Cell Res 2013; 319:2368-74. [PMID: 23769912 DOI: 10.1016/j.yexcr.2013.05.033] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2013] [Accepted: 05/29/2013] [Indexed: 12/18/2022]
Abstract
Intellectual disability (ID) imposes a major medical and social-economical problem in our society. It is defined as a global reduction in cognitive and intellectual abilities, associated with impaired social adaptation. The causes of ID are extremely heterogeneous and include non-genetic and genetic changes. Great progress has been made over recent years towards the identification of ID-related genes, resulting in a list of approximately 450 genes. A prominent neuropathological feature of patients with ID is altered dendritic spine morphogenesis. These structural abnormalities, in part, reflect impaired cytoskeleton remodeling and are associated with synaptic dysfunction. The dynamic, actin-rich nature of dendritic spines points to the Rho GTPase family as a central contributor, since they are key regulators of actin dynamics and organization. It is therefore not surprising that mutations in genes encoding regulators and effectors of the Rho GTPases have been associated with ID. This review will focus on the role of Rho GTPase signaling in synaptic structure/function and ID.
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Affiliation(s)
- Wei Ba
- Donders Institute for Brain Cognition and Behavior, Radboud University Nijmegen Medical Center, Department Cognitive Neuroscience, the Netherlands
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25
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Peters EC, Gossett AJ, Goldstein B, Der CJ, Reiner DJ. Redundant canonical and noncanonical Caenorhabditis elegans p21-activated kinase signaling governs distal tip cell migrations. G3 (BETHESDA, MD.) 2013; 3:181-95. [PMID: 23390595 PMCID: PMC3564979 DOI: 10.1534/g3.112.004416] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/13/2012] [Accepted: 11/27/2012] [Indexed: 11/18/2022]
Abstract
p21-activated kinases (Paks) are prominent mediators of Rac/Cdc42-dependent and -independent signaling and regulate signal transduction and cytoskeletal-based cell movements. We used the reproducible migrations of the Caenorhabditis elegans gonadal distal tip cells to show that two of the three nematode Pak proteins, MAX-2 and PAK-1, function redundantly in regulation of cell migration but are regulated by very different mechanisms. First, we suggest that MAX-2 requires CED-10/Rac function and thus functions canonically. Second, PIX-1 and GIT-1 function in the same role as PAK-1, and PAK-1 interaction with PIX-1 is required for PAK-1 activity; thus, PAK-1 functions noncanonically. The human Pak-Pix-Git complex is central to noncanonical Pak signaling and requires only modest Rac/CDC-42 input. Unlike the human complex, our results suggest that the C. elegans Pak-Pix-Git complex requires PAK-1 kinase domain activity. This study delineates signaling network relationships in this cell migration model, thus providing potential further mechanistic insights and an assessment of total Pak contribution to cell migration events.
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Affiliation(s)
- Eldon C. Peters
- Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, North Carolina 27599
| | - Andrea J. Gossett
- Department of Biology, University of North Carolina, Chapel Hill, North Carolina 27599
| | - Bob Goldstein
- Department of Biology, University of North Carolina, Chapel Hill, North Carolina 27599
| | - Channing J. Der
- Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, North Carolina 27599
- Department of Pharmacology, University of North Carolina, Chapel Hill, North Carolina 27599
| | - David J. Reiner
- Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, North Carolina 27599
- Department of Pharmacology, University of North Carolina, Chapel Hill, North Carolina 27599
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26
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Combeau G, Kreis P, Domenichini F, Amar M, Fossier P, Rousseau V, Barnier JV. The p21-activated kinase PAK3 forms heterodimers with PAK1 in brain implementing trans-regulation of PAK3 activity. J Biol Chem 2012; 287:30084-96. [PMID: 22815483 DOI: 10.1074/jbc.m112.355073] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
p21-activated kinase 1 (PAK1) and PAK3 belong to group I of the PAK family and control cell movement and division. They also regulate dendritic spine formation and maturation in the brain, and play a role in synaptic transmission and synaptic plasticity. PAK3, in particular, is known for its implication in X-linked intellectual disability. The pak3 gene is expressed in neurons as a GTPase-regulated PAK3a protein and also as three splice variants which display constitutive kinase activity. PAK1 regulation is based on its homodimerization, forming an inactive complex. Here, we analyze the PAK3 capacity to dimerize and show that although PAK3a is able to homodimerize, it is more likely to form heterodimeric complexes with PAK1. We further show that two intellectual disability mutations impair dimerization with PAK1. The b and c inserts present in the regulatory domain of PAK3 splice variants decrease the dimerization but retain the capacity to form heterodimers with PAK1. PAK1 and PAK3 are co-expressed in neurons, are colocalized within dendritic spines, co-purify with post-synaptic densities, and co-immunoprecipitate in brain lysates. Using kinase assays, we demonstrate that PAK1 inhibits the activity of PAK3a but not of the splice variant PAK3b in a trans-regulatory manner. Altogether, these results show that PAK3 and PAK1 signaling may be coordinated by heterodimerization.
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Affiliation(s)
- Gaëlle Combeau
- Centre de Neurosciences Paris-Sud, Université Paris-Sud, UMR 8195 and CNRS, UMR 8195, Orsay F-91405, France
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27
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Abstract
Genetic causes of intellectual disability (ID) include mutations in proteins with various functions. However, many of these proteins are enriched in synapses and recent investigations point out their crucial role in the subtle regulation of synaptic activity and dendritic spine morphogenesis. Moreover, in addition to genetic data, functional and animal model studies are providing compelling evidence that supports the emerging unifying synapse-based theory for cognitive deficit. In this review, we highlight ID-related gene products involved in synaptic morphogenesis and function, with a particular focus on the emergent signaling pathways involved in synaptic plasticity whose disruption results in cognitive deficit.
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Lei M, Ke Y, Solaro RJ. Pak1: steps towards understanding the regulatory mechanisms of pacemaker function of the heart. Future Cardiol 2010; 3:473-6. [PMID: 19804297 DOI: 10.2217/14796678.3.5.473] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
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30
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Rush ET, Schaefer GB. Identification of an X-linked deletion syndrome through comparative genomic hybridization microarray. Semin Pediatr Neurol 2010; 17:51-3. [PMID: 20434696 DOI: 10.1016/j.spen.2010.02.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
We present a single case of a young man with multiple congenital anomalies. For years, a unifying diagnosis could not be made. As his case developed, more clues came to light, but still no recognizable pattern could be identified. Ultimately, the combination of orofacial clefting, neurosensory hearing loss, choroideremia, and cognitive delays were shown to be due to an Xq21 [corrected] micro-deletion as seen on comparative genomic hybridizations studies. A review of the genes contained in this region clearly explain his constellation of findings.
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Affiliation(s)
- Eric T Rush
- Department of Pediatrics, University of Nebraska Medical Center, Omaha, NE, USA
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31
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Hoischen A, Landwehr C, Kabisch S, Ding XQ, Trost D, Stropahl G, Wigger M, Radlwimmer B, Weber RG, Haffner D. Array-CGH in unclear syndromic nephropathies identifies a microdeletion in Xq22.3-q23. Pediatr Nephrol 2009; 24:1673-81. [PMID: 19444485 DOI: 10.1007/s00467-009-1184-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/27/2009] [Revised: 03/08/2009] [Accepted: 03/13/2009] [Indexed: 12/14/2022]
Abstract
To investigate whether submicroscopic chromosomal deletions or duplications can be causative of unclear syndromic nephropathies, we analyzed ten patients with congenital abnormalities of the kidney and urinary tract or glomerulopathies combined with important extrarenal anomalies by whole-genome array-based comparative genomic hybridization. In a 14-year-old girl presenting with hematuria, proteinuria, mental retardation (MR), sensorineural hearing loss, dysmorphisms, and epilepsy, we detected a microdeletion in chromosome Xq22.3-q23. This deletion was verified and characterized by fluorescence in situ hybridization and multiplex ligation-dependent probe amplification analyses, found to be de novo, uniallelic and 3.3 Mb in size. Electron microscopy of a kidney biopsy showed glomerular basement membrane thinning and segmental splitting of the lamina densa compatible with Alport syndrome. Cranial magnetic resonance and diffusion tensor imaging detected a severe neuronal migration disorder with double cortex formation and pronounced reduction of the fronto-occipital tract system. Thus, in one of ten patients with unclear syndromic nephropathies we identified a previously undescribed contiguous gene syndrome at Xq22.3-q23. The microdeletion contains the X-linked Alport syndrome gene COL4A5, the MR genes FACL4 and PAK3, and parts of the X-chromosomal lissencephaly gene DCX associated with double cortex formation in girls, MR, and epilepsy. The phenotype in our patient combines features of the Alport-MR contiguous gene syndrome with lissencephaly.
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Affiliation(s)
- Alexander Hoischen
- Institute of Human Genetics, Rheinische Friedrich-Wilhelms-University, Bonn, Germany
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32
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Abstract
The p21-activated kinase (PAK) family of serine/threonine kinases is important in physiological processes including motility, survival, mitosis, transcription and translation. PAKs are evolutionally conserved and widely expressed in a variety of tissues and are often overexpressed in multiple cancer types. Depending on structural and functional similarities, the six members of PAK family are divided into two groups with three members in each group. Group I PAKs are activated by extracellular signals through GTPase-dependent and GTPase-independent mechanisms. In contrast, group II PAKs are constitutively active. Over the years, accumulating data from tissue culture models and human tumors has increased our understanding about the biology of PAK family members. In this review, we have summarized the complex regulation of PAK and its downstream diverse myriads of effectors, which in turn are responsible for the biological effects of PAK family of kinases in cancer cells.
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33
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Delpire E. The mammalian family of sterile 20p-like protein kinases. Pflugers Arch 2009; 458:953-67. [PMID: 19399514 DOI: 10.1007/s00424-009-0674-y] [Citation(s) in RCA: 97] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2009] [Accepted: 04/15/2009] [Indexed: 12/12/2022]
Abstract
Twenty-eight kinases found in mammalian genomes share similarity to the budding yeast kinase Ste20p. This review article examines the biological function of these mammalian Ste20 kinases. Some of them have conserved the Ste20p function of transducing extracellular signals to mitogen-activated kinases. Others affect ion transport, cell cycle, cytoskeleton organization, and program cell death. A number of molecular details involved in the activation of the kinases are discussed including autophosphorylation, substrate recognition, autoinhibition, dimerization, and substrate binding.
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Affiliation(s)
- Eric Delpire
- Department of Anesthesiology, Vanderbilt University Medical Center, T-4202 MCN 1161 21st Avenue South, Nashville, TN 37232-2520, USA.
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34
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Ke Y, Lei M, Solaro RJ. Regulation of cardiac excitation and contraction by p21 activated kinase-1. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2009; 98:238-50. [PMID: 19351515 DOI: 10.1016/j.pbiomolbio.2009.01.007] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Cardiac excitation and contraction are regulated by a variety of signaling molecules. Central to the regulatory scheme are protein kinases and phosphatases that carry out reversible phosphorylation of different effectors. The process of beta-adrenergic stimulation mediated by cAMP dependent protein kinase (PKA) forms a well-known pathway considered as the most significant control mechanism in excitation and contraction as well as many other regulatory mechanisms in cardiac function. However, although dephosphorylation pathways are critical to these regulatory processes, signaling to phosphatases is relatively poorly understood. Emerging evidence indicates that regulation of phosphatases, which dampen the effect of beta-adrenergic stimulation, is also important. We review here functional studies of p21 activated kinase-1 (Pak1) and its potential role as an upstream signal for protein phosphatase PP2A in the heart. Pak1 is a serine/threonine protein kinase directly activated by the small GTPases Cdc42 and Rac1. Pak1 is highly expressed in different regions of the heart and modulates the activities of ion channels, sarcomeric proteins, and other phosphoproteins through up-regulation of PP2A activity. Coordination of Pak1 and PP2A activities is not only potentially involved in regulation of normal cardiac function, but is likely to be important in patho-physiological conditions.
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Affiliation(s)
- Yunbo Ke
- The Department of Physiology and Biophysics and Center for Cardiovascular Research, University of Illinois at Chicago, College of Medicine, Room 202, COMRB, 835 South Wolcott Avenue, Chicago, IL 60612, USA
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35
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Morrow EM, Kane A, Goff DC, Walsh CA. Sequence analysis of P21-activated kinase 3 (PAK3) in chronic schizophrenia with cognitive impairment. Schizophr Res 2008; 106:265-7. [PMID: 18805672 PMCID: PMC2631562 DOI: 10.1016/j.schres.2008.08.021] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/21/2008] [Revised: 08/15/2008] [Accepted: 08/15/2008] [Indexed: 10/21/2022]
Abstract
The P21-activated kinase PAK3 is critical for cognitive development and truncating mutations cause non-syndromic mental retardation (MR). Missense mutations are also associated with psychotic disorders, most commonly with schizophrenia involving premorbid MR, namely "pfropfschizophrenie". We set out to measure the frequency of sequence variants in PAK3 in schizophrenia without premorbid MR. We conducted complete gene reseqeuncing of all coding exons and exon-intron boundaries in patients with schizophrenia with cognitive impairment but without premorbid MR. Deleterious variants in schizophrenia alone were rare (<1/159 or 0.6%). Thereby, while PAK3 remains a strong biological candidate in psychosis, evidence from human genetics provides strongest support for a link to pfropfschizophrenie and not to schizophrenia without premorbid intellectual disability.
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Affiliation(s)
- Eric M. Morrow
- Division of Neurogenetics and Howard Hughes Medical Institute, Department of Neurology, Beth Israel Deaconess Medical Center, and Division of Genetics, Children’s Hospital Boston, Harvard Medical School, New Research Building 266, 77 Avenue Louis Pasteur, Boston, MA 02115, USA, Schizophrenia Research Program, Department of Psychiatry, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA
| | - Anna Kane
- Division of Neurogenetics and Howard Hughes Medical Institute, Department of Neurology, Beth Israel Deaconess Medical Center, and Division of Genetics, Children’s Hospital Boston, Harvard Medical School, New Research Building 266, 77 Avenue Louis Pasteur, Boston, MA 02115, USA
| | - Donald C. Goff
- Schizophrenia Research Program, Department of Psychiatry, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA
| | - Christopher A. Walsh
- Division of Neurogenetics and Howard Hughes Medical Institute, Department of Neurology, Beth Israel Deaconess Medical Center, and Division of Genetics, Children’s Hospital Boston, Harvard Medical School, New Research Building 266, 77 Avenue Louis Pasteur, Boston, MA 02115, USA,Corresponding Author: , 617-667-0813 (tel), 617-667-0815 (fax)
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36
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Kreis P, Barnier JV. PAK signalling in neuronal physiology. Cell Signal 2008; 21:384-93. [PMID: 19036346 DOI: 10.1016/j.cellsig.2008.11.001] [Citation(s) in RCA: 104] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2008] [Accepted: 11/06/2008] [Indexed: 12/11/2022]
Abstract
Group I p21-activated kinases are a family of key effectors of Rac1 and Cdc42 and they regulate many aspects of cellular function, such as cytoskeleton dynamics, cell movement and cell migration, cell proliferation and differentiation, and gene expression. The three genes PAK1/2/3 are expressed in brain and recent evidence indicates their crucial roles in neuronal cell fate, in axonal guidance and neuronal polarisation, and in neuronal migration. Moreover they are implicated in neurodegenerative diseases and play an important role in synaptic plasticity, with PAK3 being specifically involved in mental retardation. The main goal of this review is to describe the molecular mechanisms that govern the different functions of group I PAK in neuronal signalling and to discuss the specific functions of each isoform.
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Affiliation(s)
- Patricia Kreis
- CNRS, Institut de Neurobiologie Alfred Fessard-FRC2118, Laboratoire de Neurobiologie Cellulaire et Moléculaire-UPR9040, Gif sur Yvette, France.
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37
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Kreis P, Rousseau V, Thvenot E, Combeau G, Barnier JV. The four mammalian splice variants encoded by the p21-activated kinase 3 gene have different biological properties. J Neurochem 2008; 106:1184-97. [DOI: 10.1111/j.1471-4159.2008.05474.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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38
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Rejeb I, Saillour Y, Castelnau L, Julien C, Bienvenu T, Taga P, Chaabouni H, Chelly J, Ben Jemaa L, Bahi-Buisson N. A novel splice mutation in PAK3 gene underlying mental retardation with neuropsychiatric features. Eur J Hum Genet 2008; 16:1358-63. [PMID: 18523455 DOI: 10.1038/ejhg.2008.103] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
PAK3-related mental retardation represents a rare cause of X-linked mental retardation associated with behavioural symptoms. So far, four families carrying PAK3 mutations have been reported, and in most cases PAK3 dysfunction resulted from missense mutations thought to affect either the catalytic or the N-terminal regulatory domain activity. Here, we report on a Tunisian family of X-linked moderate mental retardation with behavioural symptoms, common dysmorphic features, oro-motor impairment and secondary microcephaly. Linkage analysis showed that affected male subjects and obligate carrier female subjects share a common haplotype in the Xp21.31 - Xq23 region that contains the PAK3 gene. Direct sequencing of PAK3 coding exons and flanking intronic sequences allowed us to identify the first splice mutation in PAK3 gene located at the 5' end of intron 6 (c.276+4A>G), which results in a complete switch-off of the genuine donor splice site and an activation of a cryptic donor splice site (GTAAG) located four nucleotides downstream to the genuine one. RT-PCR experiments using the RNA from the patient's lymphoblasts showed that PAK3 transcripts contain four additional nucleotides that lead to a disruption of reading frame with a premature stop codon at position 128. Together with previously reported observations, our data further confirm that PAK3 mutations result in a specific form of X-linked mental retardation with fairly constant clinical features.
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Affiliation(s)
- Imen Rejeb
- Maladies Hereditaires et Congenitales, Service des Maladies Héréditaires et Congénitales, Hôpital Charles Nicole, Tunis, Tunisia
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39
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Basel-Vanagaite L, Rainshtein L, Inbar D, Gothelf D, Hennekam R, Straussberg R. Autosomal recessive mental retardation syndrome with anterior maxillary protrusion and strabismus: MRAMS syndrome. Am J Med Genet A 2008; 143A:1687-91. [PMID: 17618476 DOI: 10.1002/ajmg.a.31810] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
We report on a family in whom the combination of mental retardation (MR), anterior maxillary protrusion, and strabismus segregates. The healthy, consanguineous parents (first cousins) of Israeli-Arab descent had 11 children, 7 of whom (5 girls) were affected. They all had severe MR. Six of the seven had anterior maxillary protrusion with vertical maxillary excess, open bite, and prominent crowded teeth. None of the sibs with normal intelligence had jaw or dental anomalies. The child with MR but without a jaw anomaly was somewhat less severely retarded, had seizures and severe psychosis, which may point to his having a separate disorder. Biochemical and neurological studies, including brain MRI and standard cytogenetic studies, yielded normal results; fragile X was excluded, no subtelomeric rearrangements were detectable, and X-inactivation studies in the mother showed random inactivation. We have been unable to find a similar disorder in the literature, and suggest that this is a hitherto unreported autosomal recessive disorder, which we propose to name MRAMS (mental retardation, anterior maxillary protrusion, and strabismus).
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Affiliation(s)
- Lina Basel-Vanagaite
- Department of Medical Genetics, Schneider Children's Medical Center of Israel and Rabin Medical Center, Beilinson Campus, Petah Tikva, Israel.
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40
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Kasri NN, Govek EE, Van Aelst L. Characterization of oligophrenin-1, a RhoGAP lost in patients affected with mental retardation: lentiviral injection in organotypic brain slice cultures. Methods Enzymol 2008; 439:255-66. [PMID: 18374170 DOI: 10.1016/s0076-6879(07)00419-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Mutations in regulators and effectors of the Rho GTPases underlie various forms of mental retardation (MR). Among them, oligophrenin-1 (OPHN1), which encodes a Rho-GTPase activating protein, was one of the first Rho-linked MR genes identified. Upon characterization of OPHN1 in hippocampal brain slices, we obtained evidence for the requirement of OPHN1 in dendritic spine morphogenesis and neuronal function of CA1 pyramidal neurons. Organotypic hippocampal brain slice cultures are commonly used as a model system to investigate the morphology and synaptic function of neurons, mainly because they allow for the long-term examination of neurons in a preparation where the gross cellular architecture of the hippocampus is retained. In addition, maintenance of the trisynaptic circuitry in hippocampal slices enables the study of synaptic connections. Today, a multitude of gene transfer methods for postmitotic neurons in brain slices are available to easily manipulate and scrutinize the involvement of signaling molecules, such as Rho GTPases, in specific cellular processes in this system. This chapter covers techniques detailing the preparation and culturing of organotypic hippocampal brain slices, as well as the production and injection of lentivirus into brain slices.
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Affiliation(s)
- Nael Nadif Kasri
- Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, USA
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41
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Peippo M, Koivisto AM, Särkämö T, Sipponen M, von Koskull H, Ylisaukko-oja T, Rehnström K, Froyen G, Ignatius J, Järvelä I. PAK3 related mental disability: further characterization of the phenotype. Am J Med Genet A 2007; 143A:2406-16. [PMID: 17853471 DOI: 10.1002/ajmg.a.31956] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
We report clinical, neuropsychological and molecular findings in affected males and carrier females in the fourth reported family with mental retardation caused by mutation in the PAK3 gene (Xq22.3-q23), W446S. In contrast to previous reports, carrier females manifested learning problems and mild mental disability. Skewed X-inactivation was observed here for the first time in carriers of PAK3 mutation. Neuropsychological tests in affected males and carrier females suggested a common neuropsychological profile of impaired spatial cognitive abilities and defects in attentional and executive functions. The five affected males examined herein had a proportionally small head size or microcephaly, large ears, oral motor hypotonia with drooling and inarticulate speech and short attention span, anxiety, restlessness, and aggression. Brain imaging showed signs of chronic non-progressive hydrocephalus in one patient who manifested psychosis and fluctuant gait deterioration, while two other patients showed no abnormalities. EEG recordings were available from four affected males and one carrier female, and all showed similar posterior slow wave activity without epileptic discharges. Only one affected male in the family suffered from epilepsy. When comparing the affected males in this family and the three previously reported families with mental retardation due to a PAK3 mutation, similarities in their characteristics were small head size or microcephaly, large ears, speech defects, behavioral abnormalities, and psychiatric disease.
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Affiliation(s)
- Maarit Peippo
- Department of Medical Genetics, Family Federation of Finland, Helsinki, Finland.
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42
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Nadif Kasri N, Van Aelst L. Rho-linked genes and neurological disorders. Pflugers Arch 2007; 455:787-97. [PMID: 18004590 DOI: 10.1007/s00424-007-0385-1] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2006] [Accepted: 10/29/2007] [Indexed: 12/11/2022]
Abstract
Mental retardation (MR) is a common cause of intellectual disability and affects approximately 2 to 3% of children and young adults. Many forms of MR are associated with abnormalities in dendritic structure and/or dendritic spine morphology. Given that dendritic spine morphology has been tightly linked to synaptic activity, altered spine morphology has been suggested to underlie or contribute to the cognitive disabilities associated with MR. The structure and dynamics of dendritic spines is determined by its underlying actin cytoskeleton. Signaling molecules and cascades important for cytoskeletal regulation have therefore attracted a great deal of attention. As key regulators of both the actin and microtubule cytoskeletons, it is not surprising that the Rho GTPases have emerged as important regulators of dendrite and spine structural plasticity. Significantly, mutations in regulators and effectors of Rho GTPases have been associated with diseases affecting the nervous system, including MR and amyotrophic lateral sclerosis (ALS). Here, we will discuss Rho GTPase-related genes and their signaling pathways involved in MR and ALS.
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Affiliation(s)
- Nael Nadif Kasri
- Cold Spring Harbor Laboratory, 1 Bungtown Road, Demerec Building, Cold Spring Harbor, NY 11724, USA.
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43
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Kreis P, Thévenot E, Rousseau V, Boda B, Muller D, Barnier JV. The p21-activated kinase 3 implicated in mental retardation regulates spine morphogenesis through a Cdc42-dependent pathway. J Biol Chem 2007; 282:21497-506. [PMID: 17537723 DOI: 10.1074/jbc.m703298200] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The p21-activated kinase 3 (PAK3) is one of the recently identified genes for which mutations lead to nonsyndromic mental retardation. PAK3 is implicated in dendritic spine morphogenesis and is a key regulator of synaptic functions. However, the underlying roles of PAK3 in these processes remain poorly understood. We report here that the three mutations R419X, A365E, and R67C, responsible for mental retardation have different effects on the biological functions of PAK3. The R419X and A365E mutations completely abrogate the kinase activity. The R67C mutation drastically decreases the binding of PAK3 to the small GTPase Cdc42 and impairs its subsequent activation by this GTPase. We also report that PAK3 binds significantly more Cdc42 than Rac1 and is selectively activated by endogenous Cdc42, suggesting that PAK3 is a specific effector of Cdc42. Interestingly, the expression of the three mutated proteins in hippocampal neurons affects spinogenesis differentially. Both kinase-dead mutants slightly decrease the number of spines but profoundly alter spine morphology, whereas expression of the R67C mutant drastically decreases spine density. These results demonstrate that the Cdc42/PAK3 is a key module in dendritic spine formation and synaptic plasticity.
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Affiliation(s)
- Patricia Kreis
- CNRS, Institut de Neurobiologie Alfred Fessard, FRC2118, Laboratoire de Neurobiologie Cellulaire et Moléculaire, UPR9040, 1 avenue de la terrasse, Gif sur Yvette, F-91198, France
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44
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Zhao L, Ma QL, Calon F, Harris-White ME, Yang F, Lim GP, Morihara T, Ubeda OJ, Ambegaokar S, Hansen JE, Weisbart RH, Teter B, Frautschy SA, Cole GM. Role of p21-activated kinase pathway defects in the cognitive deficits of Alzheimer disease. Nat Neurosci 2006; 9:234-42. [PMID: 16415866 DOI: 10.1038/nn1630] [Citation(s) in RCA: 250] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2005] [Accepted: 12/12/2005] [Indexed: 11/08/2022]
Abstract
Defects in dendritic spines are common to several forms of cognitive deficits, including mental retardation and Alzheimer disease. Because mutation of p21-activated kinase (PAK) can lead to mental retardation and because PAK-cofilin signaling is critical in dendritic spine morphogenesis and actin dynamics, we hypothesized that the PAK pathway is involved in synaptic and cognitive deficits in Alzheimer disease. Here, we show that PAK and its activity are markedly reduced in Alzheimer disease and that this is accompanied by reduced and redistributed phosphoPAK, prominent cofilin pathology and downstream loss of the spine actin-regulatory protein drebrin, which cofilin removes from actin. We found that beta-amyloid (Abeta) was directly involved in PAK signaling deficits and drebrin loss in Abeta oligomer-treated hippocampal neurons and in the Appswe transgenic mouse model bearing a double mutation leading to higher Abeta production. In addition, pharmacological PAK inhibition in adult mice was sufficient to cause similar cofilin pathology, drebrin loss and memory impairment, consistent with a potential causal role of PAK defects in cognitive deficits in Alzheimer disease.
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Affiliation(s)
- Lixia Zhao
- Greater Los Angeles Veterans Affairs Healthcare System, Sepulveda, California 91343, USA
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45
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Abstract
Mental retardation is more common in males than females in the population, assumed to be due to mutations on the X chromosome. The prevalence of the 24 genes identified to date is low and less common than expansions in FMR1, which cause Fragile X syndrome. Systematic screening of all other X linked genes in X linked families with mental retardation is currently not feasible in a clinical setting. The phenotypes of genes causing syndromic and non-syndromic mental retardation (NLGN3, NLGN4, RPS6KA3(RSK2), OPHN1, ATRX, SLC6A8, ARX, SYN1, AGTR2, MECP2, PQBP1, SMCX, and SLC16A2) are first discussed, as these may be the focus of more targeted mutation analysis. Secondly, the relative prevalence of genes causing only non-syndromic mental retardation (IL1RAPL1, TM4SF2, ZNF41, FTSJ1, DLG3, FACL4, PAK3, ARHGEF6, FMR2, and GDI) is summarised. Thirdly, the problem of recurrence risk where a molecular genetics diagnosis has not been made and what proportion of the male excess of mental retardation is due to monogenic disorders of the X chromosome are discussed.
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Affiliation(s)
- F L Raymond
- Cambridge Institute of Medical Research, Department of Medical Genetics, University of Cambridge, Addenbrooke's Hospital, Cambridge, CB2 2XY, UK.
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46
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Newey SE, Velamoor V, Govek EE, Van Aelst L. Rho GTPases, dendritic structure, and mental retardation. ACTA ACUST UNITED AC 2005; 64:58-74. [PMID: 15884002 DOI: 10.1002/neu.20153] [Citation(s) in RCA: 276] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
A consistent feature of neurons in patients with mental retardation is abnormal dendritic structure and/or alterations in dendritic spine morphology. Deficits in the regulation of the dendritic cytoskeleton affect both the structure and function of dendrites and synapses and are believed to underlie mental retardation in some instances. In support of this, there is good evidence that alterations in signaling pathways involving the Rho family of small GTPases, key regulators of the actin and microtubule cytoskeletons, contribute to both syndromic and nonsyndromic mental retardation disorders. Because the Rho GTPases have been shown to play increasingly well-defined roles in determining dendrite and dendritic spine development and morphology, Rho signaling has been suggested to be important for normal cognition. The purpose of this review is to summarize recent data on the Rho GTPases pertaining to dendrite and dendritic spine morphogenesis, as well as to highlight their involvement in mental retardation resulting from a variety of genetic mutations within regulators and effectors of these molecules.
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Boda B, Alberi S, Nikonenko I, Node-Langlois R, Jourdain P, Moosmayer M, Parisi-Jourdain L, Muller D. The mental retardation protein PAK3 contributes to synapse formation and plasticity in hippocampus. J Neurosci 2005; 24:10816-25. [PMID: 15574732 PMCID: PMC6730202 DOI: 10.1523/jneurosci.2931-04.2004] [Citation(s) in RCA: 142] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Mutations of the gene coding for PAK3 (p21-activated kinase 3) are associated with X-linked, nonsyndromic forms of mental retardation (MRX) in which the only distinctive clinical feature is the cognitive deficit. The mechanisms through which PAK3 mutation produces the mental handicap remain unclear, although an involvement in the mechanisms that regulate the formation or plasticity of synaptic networks has been proposed. Here we show, using a transient transfection approach, that antisense and small interfering RNA-mediated suppression of PAK3 or expression of a dominant-negative PAK3 carrying the human MRX30 mutation in rat hippocampal organotypic slice cultures results in the formation of abnormally elongated dendritic spines and filopodia-like protrusions and a decrease in mature spine synapses. Ultrastructural analysis of the changes induced by expression of PAK3 carrying the MRX30 mutation reveals that many elongated spines fail to express postsynaptic densities or contact presynaptic terminals. These defects are associated with a reduced spontaneous activity, altered expression of AMPA-type glutamate receptors, and defective long-term potentiation. Together, these data identify PAK3 as a key regulator of synapse formation and plasticity in the hippocampus and support interpretations that these defects might contribute to the cognitive deficits underlying this form of mental retardation.
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MESH Headings
- Amino Acid Substitution
- Animals
- Biolistics
- Cell Line, Tumor/ultrastructure
- Codon, Nonsense
- Cognition Disorders/genetics
- Cognition Disorders/physiopathology
- Dendrites/ultrastructure
- Genes, Dominant
- Hippocampus/drug effects
- Hippocampus/metabolism
- Hippocampus/ultrastructure
- Humans
- Long-Term Potentiation
- Mental Retardation, X-Linked/genetics
- Mental Retardation, X-Linked/physiopathology
- Mental Retardation, X-Linked/psychology
- Mice
- Morphogenesis
- Mutation, Missense
- NIH 3T3 Cells
- Neuroblastoma/pathology
- Organ Culture Techniques
- Protein Serine-Threonine Kinases/chemistry
- Protein Serine-Threonine Kinases/deficiency
- Protein Serine-Threonine Kinases/genetics
- Protein Serine-Threonine Kinases/physiology
- Protein Structure, Tertiary
- Pseudopodia/ultrastructure
- Pyramidal Cells/physiology
- RNA, Antisense/pharmacology
- RNA, Antisense/toxicity
- RNA, Small Interfering/pharmacology
- RNA, Small Interfering/toxicity
- Rats
- Receptors, AMPA/deficiency
- Recombinant Fusion Proteins/physiology
- Transfection
- p21-Activated Kinases
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Affiliation(s)
- Bernadett Boda
- Department of Basic Neuroscience, Centre Medical Universitaire, 1211 Geneva 4, Switzerland
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Abstract
p21-activated kinases (Paks) are a highly conserved family of enzymes that bind to and are activated by small GTPases of the Cdc42 and Rac families. With the notable exception of plants, nearly all eukaryotes encode one or more Pak genes, indicating an ancient origin and important function for this family of enzymes. Genetic approaches in many different experimental systems, ranging from yeast to mice, are beginning to decipher the different functions of Paks. Although some of these functions are unique to a given organism, certain common themes have emerged, such as the activation of mitogen-activated protein kinase (MAPK) cascades and the regulation of cytoskeletal structure through effects on the actin and tubulin cytoskeletons.
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Affiliation(s)
- Clemens Hofmann
- Fox Chase Cancer Center, 333 Cottman Avenue, Philadelphia, PA 19111, USA
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Abstract
Our brain serves as a center for cognitive function and neurons within the brain relay and store information about our surroundings and experiences. Modulation of this complex neuronal circuitry allows us to process that information and respond appropriately. Proper development of neurons is therefore vital to the mental health of an individual, and perturbations in their signaling or morphology are likely to result in cognitive impairment. The development of a neuron requires a series of steps that begins with migration from its birth place and initiation of process outgrowth, and ultimately leads to differentiation and the formation of connections that allow it to communicate with appropriate targets. Over the past several years, it has become clear that the Rho family of GTPases and related molecules play an important role in various aspects of neuronal development, including neurite outgrowth and differentiation, axon pathfinding, and dendritic spine formation and maintenance. Given the importance of these molecules in these processes, it is therefore not surprising that mutations in genes encoding a number of regulators and effectors of the Rho GTPases have been associated with human neurological diseases. This review will focus on the role of the Rho GTPases and their associated signaling molecules throughout neuronal development and discuss how perturbations in Rho GTPase signaling may lead to cognitive disorders.
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Affiliation(s)
- Eve-Ellen Govek
- Cold Spring Harbor Laboratory, Cold Spring Harbor, New York 11724, USA
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van Galen EJM, Ramakers GJA. Rho proteins, mental retardation and the neurobiological basis of intelligence. PROGRESS IN BRAIN RESEARCH 2005; 147:295-317. [PMID: 15581714 DOI: 10.1016/s0079-6123(04)47022-8] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
For several decades it has been known that mental retardation is associated with abnormalities in dendrites and dendritic spines. The recent cloning of eight genes which cause nonspecific mental retardation when mutated, provides an important insight into the cellular mechanisms that result in the dendritic abnormalities underlying mental retardation. Three of the encoded proteins, oligophrenin1, PAK3 and alphaPix, interact directly with Rho GTPases. Rho GTPases are key signaling proteins which integrate extracellular and intracellular signals to orchestrate coordinated changes in the actin cytoskeleton, essential for directed neurite outgrowth and the generation/rearrangement of synaptic connectivity. Although many details of the cell biology of Rho signaling in the CNS are as yet unclear, a picture is unfolding showing how mutations that cause abnormal Rho signaling result in abnormal neuronal connectivity which gives rise to deficient cognitive functioning in humans.
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Affiliation(s)
- Elly J M van Galen
- Neurons and Networks Research Group, Netherlands Institute for Brain Research, Graduate School Neurosciences Amsterdam, Meibergdreef 33, 1105 AZ Amsterdam ZO, The Netherlands
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