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Kubíková J, Ubartaitė G, Metz J, Jeske M. Structural basis for binding of Drosophila Smaug to the GPCR Smoothened and to the germline inducer Oskar. Proc Natl Acad Sci U S A 2023; 120:e2304385120. [PMID: 37523566 PMCID: PMC10410706 DOI: 10.1073/pnas.2304385120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Accepted: 06/28/2023] [Indexed: 08/02/2023] Open
Abstract
Drosophila Smaug and its orthologs comprise a family of mRNA repressor proteins that exhibit various functions during animal development. Smaug proteins contain a characteristic RNA-binding sterile-α motif (SAM) domain and a conserved but uncharacterized N-terminal domain (NTD). Here, we resolved the crystal structure of the NTD of the human SAM domain-containing protein 4A (SAMD4A, a.k.a. Smaug1) to 1.6 Å resolution, which revealed its composition of a homodimerization D subdomain and a subdomain with similarity to a pseudo-HEAT-repeat analogous topology (PHAT) domain. Furthermore, we show that Drosophila Smaug directly interacts with the Drosophila germline inducer Oskar and with the Hedgehog signaling transducer Smoothened through its NTD. We determined the crystal structure of the NTD of Smaug in complex with a Smoothened α-helical peptide to 2.0 Å resolution. The peptide binds within a groove that is formed by both the D and PHAT subdomains. Structural modeling supported by experimental data suggested that an α-helix within the disordered region of Oskar binds to the NTD of Smaug in a mode similar to Smoothened. Together, our data uncover the NTD of Smaug as a peptide-binding domain.
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Affiliation(s)
- Jana Kubíková
- Biochemistry Center, Heidelberg University, Heidelberg69120, Germany
| | | | - Jutta Metz
- Biochemistry Center, Heidelberg University, Heidelberg69120, Germany
| | - Mandy Jeske
- Biochemistry Center, Heidelberg University, Heidelberg69120, Germany
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2
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Ray S, Hewitt K. Sticky, Adaptable, and Many-sided: SAM protein versatility in normal and pathological hematopoietic states. Bioessays 2023; 45:e2300022. [PMID: 37318311 PMCID: PMC10527593 DOI: 10.1002/bies.202300022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Revised: 05/10/2023] [Accepted: 05/15/2023] [Indexed: 06/16/2023]
Abstract
With decades of research seeking to generalize sterile alpha motif (SAM) biology, many outstanding questions remain regarding this multi-tool protein module. Recent data from structural and molecular/cell biology has begun to reveal new SAM modes of action in cell signaling cascades and biomolecular condensation. SAM-dependent mechanisms underlie blood-related (hematologic) diseases, including myelodysplastic syndromes and leukemias, prompting our focus on hematopoiesis for this review. With the increasing coverage of SAM-dependent interactomes, a hypothesis emerges that SAM interaction partners and binding affinities work to fine tune cell signaling cascades in developmental and disease contexts, including hematopoiesis and hematologic disease. This review discusses what is known and remains unknown about the standard mechanisms and neoplastic properties of SAM domains and what the future might hold for developing SAM-targeted therapies.
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Affiliation(s)
- Suhita Ray
- Department of Genetics, Cell Biology and Anatomy, University of Nebraska Medical Center, Omaha, NE, 68198, United States
| | - Kyle Hewitt
- Department of Genetics, Cell Biology and Anatomy, University of Nebraska Medical Center, Omaha, NE, 68198, United States
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3
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The P-body protein 4E-T represses translation to regulate the balance between cell genesis and establishment of the postnatal NSC pool. Cell Rep 2023; 42:112242. [PMID: 36924490 DOI: 10.1016/j.celrep.2023.112242] [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: 08/25/2022] [Revised: 01/19/2023] [Accepted: 02/23/2023] [Indexed: 03/17/2023] Open
Abstract
Here, we ask how developing precursors maintain the balance between cell genesis for tissue growth and establishment of adult stem cell pools, focusing on postnatal forebrain neural precursor cells (NPCs). We show that these NPCs are transcriptionally primed to differentiate and that the primed mRNAs are associated with the translational repressor 4E-T. 4E-T also broadly associates with other NPC mRNAs encoding transcriptional regulators, and these are preferentially depleted from ribosomes, consistent with repression. By contrast, a second translational regulator, Cpeb4, associates with diverse target mRNAs that are largely ribosome associated. The 4E-T-dependent mRNA association is functionally important because 4E-T knockdown or conditional knockout derepresses proneurogenic mRNA translation and perturbs maintenance versus differentiation of early postnatal NPCs in culture and in vivo. Thus, early postnatal NPCs are primed to differentiate, and 4E-T regulates the balance between cell genesis and stem cell expansion by sequestering and repressing mRNAs encoding transcriptional regulators.
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4
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Wang XY, Zhang LN. RNA binding protein SAMD4: current knowledge and future perspectives. Cell Biosci 2023; 13:21. [PMID: 36732864 PMCID: PMC9893680 DOI: 10.1186/s13578-023-00968-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Accepted: 01/22/2023] [Indexed: 02/04/2023] Open
Abstract
SAMD4 protein family is a class of novel RNA-binding proteins that can mediate post-transcriptional regulation and translation repression in eukaryotes, which are highly conserved from yeast to humans during evolution. In mammalian cells, SAMD4 protein family consists of two members including SAMD4A/Smaug1 and SAMD4B/Smaug2, both of which contain common SAM domain that can specifically bind to different target mRNAs through stem-loop structures, also known as Smaug recognition elements (SREs), and regulate the mRNA stability, degradation and translation. In addition, SAMD4 can form the cytoplasmic mRNA silencing foci and regulate the translation of SRE-containing mRNAs in neurons. SAMD4 also can form the cytosolic membrane-less organelles (MLOs), termed as Smaug1 bodies, and regulate mitochondrial function. Importantly, many studies have identified that SAMD4 family members are involved in various pathological processes including myopathy, bone development, neural development, and cancer occurrence and progression. In this review, we mainly summarize the structural characteristics, biological functions and molecular regulatory mechanisms of SAMD4 protein family members, which will provide a basis for further research and clinical application of SAMD4 protein family.
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Affiliation(s)
- Xin-Ya Wang
- grid.28703.3e0000 0000 9040 3743Beijing International Science and Technology Cooperation Base of Antivirus Drug, Faculty of Environment and Life, Beijing University of Technology, 100124 Beijing, People’s Republic of China
| | - Li-Na Zhang
- grid.28703.3e0000 0000 9040 3743Beijing International Science and Technology Cooperation Base of Antivirus Drug, Faculty of Environment and Life, Beijing University of Technology, 100124 Beijing, People’s Republic of China
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5
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Salamon I, Rasin MR. Evolution of the Neocortex Through RNA-Binding Proteins and Post-transcriptional Regulation. Front Neurosci 2022; 15:803107. [PMID: 35082597 PMCID: PMC8784817 DOI: 10.3389/fnins.2021.803107] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Accepted: 12/16/2021] [Indexed: 12/24/2022] Open
Abstract
The human neocortex is undoubtedly considered a supreme accomplishment in mammalian evolution. It features a prenatally established six-layered structure which remains plastic to the myriad of changes throughout an organism’s lifetime. A fundamental feature of neocortical evolution and development is the abundance and diversity of the progenitor cell population and their neuronal and glial progeny. These evolutionary upgrades are partially enabled due to the progenitors’ higher proliferative capacity, compartmentalization of proliferative regions, and specification of neuronal temporal identities. The driving force of these processes may be explained by temporal molecular patterning, by which progenitors have intrinsic capacity to change their competence as neocortical neurogenesis proceeds. Thus, neurogenesis can be conceptualized along two timescales of progenitors’ capacity to (1) self-renew or differentiate into basal progenitors (BPs) or neurons or (2) specify their fate into distinct neuronal and glial subtypes which participate in the formation of six-layers. Neocortical development then proceeds through sequential phases of proliferation, differentiation, neuronal migration, and maturation. Temporal molecular patterning, therefore, relies on the precise regulation of spatiotemporal gene expression. An extensive transcriptional regulatory network is accompanied by post-transcriptional regulation that is frequently mediated by the regulatory interplay between RNA-binding proteins (RBPs). RBPs exhibit important roles in every step of mRNA life cycle in any system, from splicing, polyadenylation, editing, transport, stability, localization, to translation (protein synthesis). Here, we underscore the importance of RBP functions at multiple time-restricted steps of early neurogenesis, starting from the cell fate transition of transcriptionally primed cortical progenitors. A particular emphasis will be placed on RBPs with mostly conserved but also divergent evolutionary functions in neural progenitors across different species. RBPs, when considered in the context of the fascinating process of neocortical development, deserve to be main protagonists in the story of the evolution and development of the neocortex.
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Kuc CA, Brott JT, Thorpe HHA, Smart A, Vessey JP. Staufen 1 is expressed by neural precursor cells in the developing murine cortex but is dispensable for NPC self-renewal and neuronal differentiation in vitro. Brain Res 2021; 1773:147700. [PMID: 34678304 DOI: 10.1016/j.brainres.2021.147700] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Revised: 10/14/2021] [Accepted: 10/17/2021] [Indexed: 12/22/2022]
Abstract
BACKGROUND Proper development of the cerebral cortex relies on asymmetric divisions of neural precursor cells (NPCs) to produce a recurring NPC and a differentiated neuron. Asymmetric divisions are promoted by the differential localization of cell-fate determinants, such as mRNA, between daughter cells. Staufen 1 (Stau1) is an RNA-binding protein known to localize mRNA in mature hippocampal neurons. Its expression pattern and role in the developing mammalian cortex remains unknown. RESULTS Both stau1 mRNA and Stau1 protein were found to be expressed in all cells of the developing murine cortex. Stau1 protein expression was characterized spatially and temporally throughout cortical development and found to be present in all stages investigated. We observed expression in the nucleus, cytoplasm and distal processes of both NPCs and newly born neurons and found it to shuttle between the nucleus and the cytoplasm. Upon shRNA-mediated knock-down of Stau1 in primary cultures of the developing cortex, we did not observe any phenotype in NPCs. They were able to both self-renew and generate neurons in the absence of Stau1 expression. CONCLUSIONS We propose that Stau1 is either dispensable for the development of the cerebral cortex or that its paralogue, Stau2, is able to compensate for its loss.
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Affiliation(s)
- C A Kuc
- Department of Molecular and Cellular Biology, College of Biological Sciences, University of Guelph, Guelph, ON, Canada
| | - J T Brott
- Department of Molecular and Cellular Biology, College of Biological Sciences, University of Guelph, Guelph, ON, Canada
| | - H H A Thorpe
- Department of Molecular and Cellular Biology, College of Biological Sciences, University of Guelph, Guelph, ON, Canada
| | - A Smart
- Department of Molecular and Cellular Biology, College of Biological Sciences, University of Guelph, Guelph, ON, Canada
| | - J P Vessey
- Department of Molecular and Cellular Biology, College of Biological Sciences, University of Guelph, Guelph, ON, Canada.
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7
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Fernández-Alvarez AJ, Thomas MG, Pascual ML, Habif M, Pimentel J, Corbat AA, Pessoa JP, La Spina PE, Boscaglia L, Plessis A, Carmo-Fonseca M, Grecco HE, Casado M, Boccaccio GL. Smaug1 membrane-less organelles respond to AMPK/mTOR and affect mitochondrial function‡. J Cell Sci 2021; 135:273619. [PMID: 34859817 DOI: 10.1242/jcs.253591] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Accepted: 11/15/2021] [Indexed: 11/20/2022] Open
Abstract
Smaug is a conserved translational regulator that binds numerous mRNAs, including nuclear transcripts that encode mitochondrial enzymes. Smaug orthologs form cytosolic membrane-less organelles (MLOs) in several organisms and cell types. We have performed single-molecule FISH assays that revealed that SDHB and UQCRC1 mRNAs associate with Smaug1 bodies in U2OS cells. Loss of function of Smaug1 and Smaug2 affected both mitochondrial respiration and morphology of the mitochondrial network. Phenotype rescue by Smaug1 transfection depends on the presence of its RNA binding domain. Moreover, we identified specific Smaug1 domains involved in MLO formation, and found that impaired Smaug1 MLO condensation correlates with mitochondrial defects. Mitochondrial Complex I inhibition by rotenone -but not strong mitochondrial uncoupling by CCCP- rapidly induced Smaug1 MLOs dissolution. Metformin and rapamycin elicited similar effects, which were blocked by pharmacological inhibition of AMPK. Finally, we found that Smaug1 MLO dissolution weakens the interaction with target mRNAs, thus enabling their release. We propose that mitochondrial respiration and the AMPK/mTOR balance controls the condensation and dissolution of Smaug1 MLOs, thus regulating nuclear mRNAs that encode key mitochondrial proteins.
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Affiliation(s)
- Ana J Fernández-Alvarez
- Fundación Instituto Leloir (FIL).,Instituto de Investigaciones Bioquímicas de Buenos Aires (IIBBA) - Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), C1405BWE Buenos Aires, Argentina
| | - María Gabriela Thomas
- Fundación Instituto Leloir (FIL).,Instituto de Investigaciones Bioquímicas de Buenos Aires (IIBBA) - Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), C1405BWE Buenos Aires, Argentina
| | - Malena L Pascual
- Fundación Instituto Leloir (FIL).,Instituto de Investigaciones Bioquímicas de Buenos Aires (IIBBA) - Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), C1405BWE Buenos Aires, Argentina
| | - Martín Habif
- Department of Physics, Facultad de Ciencias Exactas y Naturales (FCEN), University of Buenos Aires, and IFIBA, CONICET, C1428EHA Buenos Aires, Argentina
| | - Jerónimo Pimentel
- Fundación Instituto Leloir (FIL).,Instituto de Investigaciones Bioquímicas de Buenos Aires (IIBBA) - Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), C1405BWE Buenos Aires, Argentina
| | - Agustín A Corbat
- Department of Physics, Facultad de Ciencias Exactas y Naturales (FCEN), University of Buenos Aires, and IFIBA, CONICET, C1428EHA Buenos Aires, Argentina
| | - João P Pessoa
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Pablo E La Spina
- Fundación Instituto Leloir (FIL).,Instituto de Investigaciones Bioquímicas de Buenos Aires (IIBBA) - Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), C1405BWE Buenos Aires, Argentina
| | | | - Anne Plessis
- Institut Jacques Monod, CNRS, UMR 7592, University Paris Diderot, Sorbonne Paris Cité, F-75205 Paris, France
| | - Maria Carmo-Fonseca
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Hernán E Grecco
- Department of Physics, Facultad de Ciencias Exactas y Naturales (FCEN), University of Buenos Aires, and IFIBA, CONICET, C1428EHA Buenos Aires, Argentina
| | - Marta Casado
- Instituto de Biomedicina de Valencia, IBV-CSIC, Valencia 46010, Spain, and Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Madrid 28029, Spain
| | - Graciela L Boccaccio
- Fundación Instituto Leloir (FIL).,Instituto de Investigaciones Bioquímicas de Buenos Aires (IIBBA) - Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET), C1405BWE Buenos Aires, Argentina.,Department of Molecular and Cellular Biology and Physiology (FBMyC), Facultad de Ciencias Exactas y Naturales (FCEN), University of Buenos Aires, C1428EHA Buenos Aires, Argentina
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8
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Chalkiadaki K, Statoulla E, Markou M, Bellou S, Bagli E, Fotsis T, Murphy C, Gkogkas CG. Translational control in neurovascular brain development. ROYAL SOCIETY OPEN SCIENCE 2021; 8:211088. [PMID: 34659781 PMCID: PMC8511748 DOI: 10.1098/rsos.211088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Accepted: 09/23/2021] [Indexed: 06/13/2023]
Abstract
The human brain carries out complex tasks and higher functions and is crucial for organismal survival, as it senses both intrinsic and extrinsic environments. Proper brain development relies on the orchestrated development of different precursor cells, which will give rise to the plethora of mature brain cell-types. Within this process, neuronal cells develop closely to and in coordination with vascular cells (endothelial cells (ECs), pericytes) in a bilateral communication process that relies on neuronal activity, attractive or repulsive guidance cues for both cell types and on tight-regulation of gene expression. Translational control is a master regulator of the gene-expression pathway and in particular for neuronal and ECs, it can be localized in developmentally relevant (axon growth cone, endothelial tip cell) and mature compartments (synapses, axons). Herein, we will review mechanisms of translational control relevant to brain development in neurons and ECs in health and disease.
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Affiliation(s)
- Kleanthi Chalkiadaki
- Division of Biomedical Research, Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, University Campus, 45110 Ioannina, Greece
| | - Elpida Statoulla
- Division of Biomedical Research, Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, University Campus, 45110 Ioannina, Greece
| | - Maria Markou
- Division of Biomedical Research, Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, University Campus, 45110 Ioannina, Greece
| | - Sofia Bellou
- Division of Biomedical Research, Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, University Campus, 45110 Ioannina, Greece
| | - Eleni Bagli
- Division of Biomedical Research, Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, University Campus, 45110 Ioannina, Greece
| | - Theodore Fotsis
- Division of Biomedical Research, Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, University Campus, 45110 Ioannina, Greece
| | - Carol Murphy
- Division of Biomedical Research, Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, University Campus, 45110 Ioannina, Greece
| | - Christos G. Gkogkas
- Division of Biomedical Research, Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, University Campus, 45110 Ioannina, Greece
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9
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Park Y, Page N, Salamon I, Li D, Rasin MR. Making sense of mRNA landscapes: Translation control in neurodevelopment. WILEY INTERDISCIPLINARY REVIEWS-RNA 2021; 13:e1674. [PMID: 34137510 DOI: 10.1002/wrna.1674] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Revised: 05/10/2021] [Accepted: 05/11/2021] [Indexed: 12/27/2022]
Abstract
Like all other parts of the central nervous system, the mammalian neocortex undergoes temporally ordered set of developmental events, including proliferation, differentiation, migration, cellular identity, synaptogenesis, connectivity formation, and plasticity changes. These neurodevelopmental mechanisms have been characterized by studies focused on transcriptional control. Recent findings, however, have shown that the spatiotemporal regulation of post-transcriptional steps like alternative splicing, mRNA traffic/localization, mRNA stability/decay, and finally repression/derepression of protein synthesis (mRNA translation) have become just as central to the neurodevelopment as transcriptional control. A number of dynamic players act post-transcriptionally in the neocortex to regulate these steps, as RNA binding proteins (RBPs), ribosomal proteins (RPs), long non-coding RNAs, and/or microRNA. Remarkably, mutations in these post-transcriptional regulators have been associated with neurodevelopmental, neurodegenerative, inherited, or often co-morbid disorders, such as microcephaly, autism, epilepsy, intellectual disability, white matter diseases, Rett-syndrome like phenotype, spinocerebellar ataxia, and amyotrophic lateral sclerosis. Here, we focus on the current state, advanced methodologies and pitfalls of this exciting and upcoming field of RNA metabolism with vast potential in understanding fundamental neurodevelopmental processes and pathologies. This article is categorized under: Translation > Translation Regulation RNA in Disease and Development > RNA in Disease RNA Interactions with Proteins and Other Molecules > Protein-RNA Interactions: Functional Implications.
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Affiliation(s)
- Yongkyu Park
- RWJ Medical School, Rutgers University, New Brunswick, New Jersey, USA
| | - Nicholas Page
- RWJ Medical School, Rutgers University, New Brunswick, New Jersey, USA
| | - Iva Salamon
- RWJ Medical School, Rutgers University, New Brunswick, New Jersey, USA
| | | | - Mladen-Roko Rasin
- RWJ Medical School, Rutgers University, New Brunswick, New Jersey, USA
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10
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Nucleocytoplasmic transport of the RNA-binding protein CELF2 regulates neural stem cell fates. Cell Rep 2021; 35:109226. [PMID: 34107259 DOI: 10.1016/j.celrep.2021.109226] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Revised: 03/23/2021] [Accepted: 05/13/2021] [Indexed: 01/12/2023] Open
Abstract
The development of the cerebral cortex requires balanced expansion and differentiation of neural stem/progenitor cells (NPCs), which rely on precise regulation of gene expression. Because NPCs often exhibit transcriptional priming of cell-fate-determination genes, the ultimate output of these genes for fate decisions must be carefully controlled in a timely fashion at the post-transcriptional level, but how that is achieved is poorly understood. Here, we report that de novo missense variants in an RNA-binding protein CELF2 cause human cortical malformations and perturb NPC fate decisions in mice by disrupting CELF2 nucleocytoplasmic transport. In self-renewing NPCs, CELF2 resides in the cytoplasm, where it represses mRNAs encoding cell fate regulators and neurodevelopmental disorder-related factors. The translocation of CELF2 into the nucleus releases mRNA for translation and thereby triggers NPC differentiation. Our results reveal that CELF2 translocation between subcellular compartments orchestrates mRNA at the translational level to instruct cell fates in cortical development.
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11
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Pryszlak M, Wiggans M, Chen X, Jaramillo JE, Burns SE, Richards LM, Pugh TJ, Kaplan DR, Huang X, Dirks PB, Pearson BJ. The DEAD-box helicase DDX56 is a conserved stemness regulator in normal and cancer stem cells. Cell Rep 2021; 34:108903. [PMID: 33789112 DOI: 10.1016/j.celrep.2021.108903] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Revised: 10/28/2020] [Accepted: 03/04/2021] [Indexed: 12/12/2022] Open
Abstract
Across the animal kingdom, adult tissue homeostasis is regulated by adult stem cell activity, which is commonly dysregulated in human cancers. However, identifying key regulators of stem cells in the milieu of thousands of genes dysregulated in a given cancer is challenging. Here, using a comparative genomics approach between planarian adult stem cells and patient-derived glioblastoma stem cells (GSCs), we identify and demonstrate the role of DEAD-box helicase DDX56 in regulating aspects of stemness in four stem cell systems: planarians, mouse neural stem cells, human GSCs, and a fly model of glioblastoma. In a human GSC line, DDX56 localizes to the nucleolus, and using planarians, when DDX56 is lost, stem cells dysregulate expression of ribosomal RNAs and lose nucleolar integrity prior to stem cell death. Together, a comparative genomic approach can be used to uncover conserved stemness regulators that are functional in both normal and cancer stem cells.
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Affiliation(s)
- Michael Pryszlak
- The Hospital for Sick Children, Program in Developmental and Stem Cell Biology, Toronto, ON M5G 0A4, Canada; University of Toronto, Department of Molecular Genetics, Toronto, ON M5S 1A8, Canada
| | - Mallory Wiggans
- The Hospital for Sick Children, Program in Developmental and Stem Cell Biology, Toronto, ON M5G 0A4, Canada; University of Toronto, Department of Molecular Genetics, Toronto, ON M5S 1A8, Canada
| | - Xin Chen
- The Hospital for Sick Children, Program in Developmental and Stem Cell Biology, Toronto, ON M5G 0A4, Canada
| | - Julia E Jaramillo
- The Hospital for Sick Children, Program in Developmental and Stem Cell Biology, Toronto, ON M5G 0A4, Canada; University of Toronto, Department of Molecular Genetics, Toronto, ON M5S 1A8, Canada
| | - Sarah E Burns
- The Hospital for Sick Children, Program in Developmental and Stem Cell Biology, Toronto, ON M5G 0A4, Canada
| | - Laura M Richards
- Department of Medical Biophysics, University of Toronto, ON M5G 1L7, Canada; Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 2C1, Canada
| | - Trevor J Pugh
- Ontario Institute for Cancer Research, Toronto, ON M5G 0A3, Canada; Department of Medical Biophysics, University of Toronto, ON M5G 1L7, Canada; Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 2C1, Canada
| | - David R Kaplan
- The Hospital for Sick Children, Program in Developmental and Stem Cell Biology, Toronto, ON M5G 0A4, Canada; University of Toronto, Department of Molecular Genetics, Toronto, ON M5S 1A8, Canada
| | - Xi Huang
- The Hospital for Sick Children, Program in Developmental and Stem Cell Biology, Toronto, ON M5G 0A4, Canada; University of Toronto, Department of Molecular Genetics, Toronto, ON M5S 1A8, Canada; Ontario Institute for Cancer Research, Toronto, ON M5G 0A3, Canada; The Hospital for Sick Children, Arthur and Sonia Labatt Brain Tumor Research Centre, Toronto, ON M5G 0A4, Canada
| | - Peter B Dirks
- The Hospital for Sick Children, Program in Developmental and Stem Cell Biology, Toronto, ON M5G 0A4, Canada; University of Toronto, Department of Molecular Genetics, Toronto, ON M5S 1A8, Canada; Ontario Institute for Cancer Research, Toronto, ON M5G 0A3, Canada; The Hospital for Sick Children, Arthur and Sonia Labatt Brain Tumor Research Centre, Toronto, ON M5G 0A4, Canada
| | - Bret J Pearson
- The Hospital for Sick Children, Program in Developmental and Stem Cell Biology, Toronto, ON M5G 0A4, Canada; University of Toronto, Department of Molecular Genetics, Toronto, ON M5S 1A8, Canada; Ontario Institute for Cancer Research, Toronto, ON M5G 0A3, Canada.
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12
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Oproescu AM, Han S, Schuurmans C. New Insights Into the Intricacies of Proneural Gene Regulation in the Embryonic and Adult Cerebral Cortex. Front Mol Neurosci 2021; 14:642016. [PMID: 33658912 PMCID: PMC7917194 DOI: 10.3389/fnmol.2021.642016] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Accepted: 01/26/2021] [Indexed: 12/21/2022] Open
Abstract
Historically, the mammalian brain was thought to lack stem cells as no new neurons were found to be made in adulthood. That dogma changed ∼25 years ago with the identification of neural stem cells (NSCs) in the adult rodent forebrain. However, unlike rapidly self-renewing mature tissues (e.g., blood, intestinal crypts, skin), the majority of adult NSCs are quiescent, and those that become 'activated' are restricted to a few neurogenic zones that repopulate specific brain regions. Conversely, embryonic NSCs are actively proliferating and neurogenic. Investigations into the molecular control of the quiescence-to-proliferation-to-differentiation continuum in the embryonic and adult brain have identified proneural genes encoding basic-helix-loop-helix (bHLH) transcription factors (TFs) as critical regulators. These bHLH TFs initiate genetic programs that remove NSCs from quiescence and drive daughter neural progenitor cells (NPCs) to differentiate into specific neural cell subtypes, thereby contributing to the enormous cellular diversity of the adult brain. However, new insights have revealed that proneural gene activities are context-dependent and tightly regulated. Here we review how proneural bHLH TFs are regulated, with a focus on the murine cerebral cortex, drawing parallels where appropriate to other organisms and neural tissues. We discuss upstream regulatory events, post-translational modifications (phosphorylation, ubiquitinylation), protein-protein interactions, epigenetic and metabolic mechanisms that govern bHLH TF expression, stability, localization, and consequent transactivation of downstream target genes. These tight regulatory controls help to explain paradoxical findings of changes to bHLH activity in different cellular contexts.
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Affiliation(s)
- Ana-Maria Oproescu
- Sunnybrook Research Institute, Biological Sciences Platform, Toronto, ON, Canada
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada
| | - Sisu Han
- Sunnybrook Research Institute, Biological Sciences Platform, Toronto, ON, Canada
- Department of Biochemistry, University of Toronto, Toronto, ON, Canada
| | - Carol Schuurmans
- Sunnybrook Research Institute, Biological Sciences Platform, Toronto, ON, Canada
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada
- Department of Biochemistry, University of Toronto, Toronto, ON, Canada
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13
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Extrinsic Regulators of mRNA Translation in Developing Brain: Story of WNTs. Cells 2021; 10:cells10020253. [PMID: 33525513 PMCID: PMC7911671 DOI: 10.3390/cells10020253] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Revised: 01/16/2021] [Accepted: 01/21/2021] [Indexed: 12/30/2022] Open
Abstract
Extrinsic molecules such as morphogens can regulate timed mRNA translation events in developing neurons. In particular, Wingless-type MMTV integration site family, member 3 (Wnt3), was shown to regulate the translation of Foxp2 mRNA encoding a Forkhead transcription factor P2 in the neocortex. However, the Wnt receptor that possibly mediates these translation events remains unknown. Here, we report Frizzled member 7 (Fzd7) as the Wnt3 receptor that lays downstream in Wnt3-regulated mRNA translation. Fzd7 proteins co-localize with Wnt3 ligands in developing neocortices. In addition, the Fzd7 proteins overlap in layer-specific neuronal subpopulations expressing different transcription factors, Foxp1 and Foxp2. When Fzd7 was silenced, we found decreased Foxp2 protein expression and increased Foxp1 protein expression, respectively. The Fzd7 silencing also disrupted the migration of neocortical glutamatergic neurons. In contrast, Fzd7 overexpression reversed the pattern of migratory defects and Foxp protein expression that we found in the Fzd7 silencing. We further discovered that Fzd7 is required for Wnt3-induced Foxp2 mRNA translation. Surprisingly, we also determined that the Fzd7 suppression of Foxp1 protein expression is not Wnt3 dependent. In conclusion, it is exhibited that the interaction between Wnt3 and Fzd7 regulates neuronal identity and the Fzd7 receptor functions as a downstream factor in ligand Wnt3 signaling for mRNA translation. In particular, the Wnt3-Fzd7 signaling axis determines the deep layer Foxp2-expressing neurons of developing neocortices. Our findings also suggest that Fzd7 controls the balance of the expression for Foxp transcription factors in developing neocortical neurons. These discoveries are presented in our manuscript within a larger framework of this review on the role of extrinsic factors in regulating mRNA translation.
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Oliveira NCM, Lins ÉM, Massirer KB, Bengtson MH. Translational Control during Mammalian Neocortex Development and Postembryonic Neuronal Function. Semin Cell Dev Biol 2020; 114:36-46. [PMID: 33020045 DOI: 10.1016/j.semcdb.2020.09.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Revised: 09/09/2020] [Accepted: 09/09/2020] [Indexed: 12/21/2022]
Abstract
The control of mRNA translation has key roles in the regulation of gene expression and biological processes such as mammalian cellular differentiation and identity. Methodological advances in the last decade have resulted in considerable progress towards understanding how translational control contributes to the regulation of diverse biological phenomena. In this review, we discuss recent findings in the involvement of translational control in the mammalian neocortex development and neuronal biology. We focus on regulatory mechanisms that modulate translational efficiency during neural stem cells self-renewal and differentiation, as well as in neuronal-related processes such as synapse, plasticity, and memory.
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Affiliation(s)
- Natássia Cristina Martins Oliveira
- Department of Biochemistry and Tissue Biology, Institute of Biology, University of Campinas - UNICAMP, 13083-862, Campinas, SP, Brazil; Center for Molecular Biology and Genetic Engineering - CBMEG, University of Campinas - UNICAMP, 13083-875, Campinas, SP, Brazil; Center of Medicinal Chemistry - CQMED, Structural Genomics Consortium - SGC, University of Campinas - UNICAMP, 13083-886, Campinas, SP, Brazil
| | - Érico Moreto Lins
- Department of Biochemistry and Tissue Biology, Institute of Biology, University of Campinas - UNICAMP, 13083-862, Campinas, SP, Brazil; PhD Program in Genetics and Molecular Biology (PGBM), UNICAMP, Campinas, SP 13083-862, Brazil
| | - Katlin Brauer Massirer
- Center for Molecular Biology and Genetic Engineering - CBMEG, University of Campinas - UNICAMP, 13083-875, Campinas, SP, Brazil; Center of Medicinal Chemistry - CQMED, Structural Genomics Consortium - SGC, University of Campinas - UNICAMP, 13083-886, Campinas, SP, Brazil
| | - Mário Henrique Bengtson
- Department of Biochemistry and Tissue Biology, Institute of Biology, University of Campinas - UNICAMP, 13083-862, Campinas, SP, Brazil; Center of Medicinal Chemistry - CQMED, Structural Genomics Consortium - SGC, University of Campinas - UNICAMP, 13083-886, Campinas, SP, Brazil.
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15
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Schieweck R, Ninkovic J, Kiebler MA. RNA-binding proteins balance brain function in health and disease. Physiol Rev 2020; 101:1309-1370. [PMID: 33000986 DOI: 10.1152/physrev.00047.2019] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Posttranscriptional gene expression including splicing, RNA transport, translation, and RNA decay provides an important regulatory layer in many if not all molecular pathways. Research in the last decades has positioned RNA-binding proteins (RBPs) right in the center of posttranscriptional gene regulation. Here, we propose interdependent networks of RBPs to regulate complex pathways within the central nervous system (CNS). These are involved in multiple aspects of neuronal development and functioning, including higher cognition. Therefore, it is not sufficient to unravel the individual contribution of a single RBP and its consequences but rather to study and understand the tight interplay between different RBPs. In this review, we summarize recent findings in the field of RBP biology and discuss the complex interplay between different RBPs. Second, we emphasize the underlying dynamics within an RBP network and how this might regulate key processes such as neurogenesis, synaptic transmission, and synaptic plasticity. Importantly, we envision that dysfunction of specific RBPs could lead to perturbation within the RBP network. This would have direct and indirect (compensatory) effects in mRNA binding and translational control leading to global changes in cellular expression programs in general and in synaptic plasticity in particular. Therefore, we focus on RBP dysfunction and how this might cause neuropsychiatric and neurodegenerative disorders. Based on recent findings, we propose that alterations in the entire regulatory RBP network might account for phenotypic dysfunctions observed in complex diseases including neurodegeneration, epilepsy, and autism spectrum disorders.
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Affiliation(s)
- Rico Schieweck
- Biomedical Center (BMC), Department for Cell Biology and Anatomy, Medical Faculty, Ludwig-Maximilians-University, Planegg-Martinsried, Germany
| | - Jovica Ninkovic
- Biomedical Center (BMC), Department for Cell Biology and Anatomy, Medical Faculty, Ludwig-Maximilians-University, Planegg-Martinsried, Germany
| | - Michael A Kiebler
- Biomedical Center (BMC), Department for Cell Biology and Anatomy, Medical Faculty, Ludwig-Maximilians-University, Planegg-Martinsried, Germany
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16
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Viral hijacking of the TENT4-ZCCHC14 complex protects viral RNAs via mixed tailing. Nat Struct Mol Biol 2020; 27:581-588. [PMID: 32451488 DOI: 10.1038/s41594-020-0427-3] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Accepted: 04/03/2020] [Indexed: 12/20/2022]
Abstract
TENT4 enzymes generate 'mixed tails' of diverse nucleotides at 3' ends of RNAs via nontemplated nucleotide addition to protect messenger RNAs from deadenylation. Here we discover extensive mixed tailing in transcripts of hepatitis B virus (HBV) and human cytomegalovirus (HCMV), generated via a similar mechanism exploiting the TENT4-ZCCHC14 complex. TAIL-seq on HBV and HCMV RNAs revealed that TENT4A and TENT4B are responsible for mixed tailing and protection of viral poly(A) tails. We find that the HBV post-transcriptional regulatory element (PRE), specifically the CNGGN-type pentaloop, is critical for TENT4-dependent regulation. HCMV uses a similar pentaloop, an interesting example of convergent evolution. This pentaloop is recognized by the sterile alpha motif domain-containing ZCCHC14 protein, which in turn recruits TENT4. Overall, our study reveals the mechanism of action of PRE, which has been widely used to enhance gene expression, and identifies the TENT4-ZCCHC14 complex as a potential target for antiviral therapeutics.
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17
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Bruzzone L, Argüelles C, Sanial M, Miled S, Alvisi G, Gonçalves-Antunes M, Qasrawi F, Holmgren RA, Smibert CA, Lipshitz HD, Boccaccio GL, Plessis A, Bécam I. Regulation of the RNA-binding protein Smaug by the GPCR Smoothened via the kinase Fused. EMBO Rep 2020; 21:e48425. [PMID: 32383557 DOI: 10.15252/embr.201948425] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2019] [Revised: 03/17/2020] [Accepted: 04/14/2020] [Indexed: 12/13/2022] Open
Abstract
From fly to mammals, the Smaug/Samd4 family of prion-like RNA-binding proteins control gene expression by destabilizing and/or repressing the translation of numerous target transcripts. However, the regulation of its activity remains poorly understood. We show that Smaug's protein levels and mRNA repressive activity are downregulated by Hedgehog signaling in tissue culture cells. These effects rely on the interaction of Smaug with the G-protein coupled receptor Smoothened, which promotes the phosphorylation of Smaug by recruiting the kinase Fused. The activation of Fused and its binding to Smaug are sufficient to suppress its ability to form cytosolic bodies and to antagonize its negative effects on endogenous targets. Importantly, we demonstrate in vivo that HH reduces the levels of smaug mRNA and increases the level of several mRNAs downregulated by Smaug. Finally, we show that Smaug acts as a positive regulator of Hedgehog signaling during wing morphogenesis. These data constitute the first evidence for a post-translational regulation of Smaug and reveal that the fate of several mRNAs bound to Smaug is modulated by a major signaling pathway.
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Affiliation(s)
- Lucia Bruzzone
- CNRS, Institut Jacques Monod, Université de Paris, Paris, France
| | | | - Matthieu Sanial
- CNRS, Institut Jacques Monod, Université de Paris, Paris, France
| | - Samia Miled
- CNRS, Institut Jacques Monod, Université de Paris, Paris, France
| | - Giorgia Alvisi
- CNRS, Institut Jacques Monod, Université de Paris, Paris, France
| | | | - Fairouz Qasrawi
- CNRS, Institut Jacques Monod, Université de Paris, Paris, France
| | - Robert A Holmgren
- Department of Mol. Biosci., Northwestern University, Evanston, IL, USA
| | - Craig A Smibert
- Department of Biochemistry, University of Toronto, Toronto, ON, Canada.,Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada
| | - Howard D Lipshitz
- Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada
| | - Graciela L Boccaccio
- Fundación Instituto Leloir, Instituto de Investigaciones Bioquímicas Buenos Aires-Consejo Nacional de Investigaciones Científicas y Tecnológicas, Facultad de Ciencias Exactas y Naturales, University of Buenos Aires, Buenos Aires, Argentina
| | - Anne Plessis
- CNRS, Institut Jacques Monod, Université de Paris, Paris, France
| | - Isabelle Bécam
- CNRS, Institut Jacques Monod, Université de Paris, Paris, France
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18
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Lennox AL, Hoye ML, Jiang R, Johnson-Kerner BL, Suit LA, Venkataramanan S, Sheehan CJ, Alsina FC, Fregeau B, Aldinger KA, Moey C, Lobach I, Afenjar A, Babovic-Vuksanovic D, Bézieau S, Blackburn PR, Bunt J, Burglen L, Campeau PM, Charles P, Chung BHY, Cogné B, Curry C, D'Agostino MD, Di Donato N, Faivre L, Héron D, Innes AM, Isidor B, Keren B, Kimball A, Klee EW, Kuentz P, Küry S, Martin-Coignard D, Mirzaa G, Mignot C, Miyake N, Matsumoto N, Fujita A, Nava C, Nizon M, Rodriguez D, Blok LS, Thauvin-Robinet C, Thevenon J, Vincent M, Ziegler A, Dobyns W, Richards LJ, Barkovich AJ, Floor SN, Silver DL, Sherr EH. Pathogenic DDX3X Mutations Impair RNA Metabolism and Neurogenesis during Fetal Cortical Development. Neuron 2020; 106:404-420.e8. [PMID: 32135084 PMCID: PMC7331285 DOI: 10.1016/j.neuron.2020.01.042] [Citation(s) in RCA: 104] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2018] [Revised: 11/05/2019] [Accepted: 01/29/2020] [Indexed: 12/16/2022]
Abstract
De novo germline mutations in the RNA helicase DDX3X account for 1%-3% of unexplained intellectual disability (ID) cases in females and are associated with autism, brain malformations, and epilepsy. Yet, the developmental and molecular mechanisms by which DDX3X mutations impair brain function are unknown. Here, we use human and mouse genetics and cell biological and biochemical approaches to elucidate mechanisms by which pathogenic DDX3X variants disrupt brain development. We report the largest clinical cohort to date with DDX3X mutations (n = 107), demonstrating a striking correlation between recurrent dominant missense mutations, polymicrogyria, and the most severe clinical outcomes. We show that Ddx3x controls cortical development by regulating neuron generation. Severe DDX3X missense mutations profoundly disrupt RNA helicase activity, induce ectopic RNA-protein granules in neural progenitors and neurons, and impair translation. Together, these results uncover key mechanisms underlying DDX3X syndrome and highlight aberrant RNA metabolism in the pathogenesis of neurodevelopmental disease.
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Affiliation(s)
- Ashley L Lennox
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710, USA
| | - Mariah L Hoye
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710, USA
| | - Ruiji Jiang
- Department of Neurology, University of California, San Francisco, San Francisco, CA 94158, USA
| | | | - Lindsey A Suit
- Department of Neurology, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Srivats Venkataramanan
- Department of Cell and Tissue Biology, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Charles J Sheehan
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710, USA
| | - Fernando C Alsina
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710, USA
| | - Brieana Fregeau
- Department of Neurology, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Kimberly A Aldinger
- Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, WA 98101, USA
| | - Ching Moey
- The University of Queensland, Queensland Brain Institute, Brisbane, QLD 4072, Australia
| | - Iryna Lobach
- Department of Epidemiology and Biostatistics, University of California San Francisco, San Francisco, CA 94158, USA
| | - Alexandra Afenjar
- Centre de référence des malformations et maladies congénitales du cervelet et Département de génétique et embryologie médicale, APHP, Sorbonne Université, Hôpital Armand Trousseau, 75012 Paris, France
| | - Dusica Babovic-Vuksanovic
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN 55905, USA; Department of Clinical Genomics, Mayo Clinic, Rochester, MN 55905, USA; Department of Pediatric and Adolescent Medicine, Mayo Clinic, Rochester, MN 55905, USA
| | - Stéphane Bézieau
- Service de Génétique Médicale, CHU Nantes, 9 quai Moncousu, 44093 Nantes Cedex 1, France; Université de Nantes, CNRS, INSERM, l'institut du thorax, 44000 Nantes, France
| | - Patrick R Blackburn
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN 55905, USA; Center for Individualized Medicine, Mayo Clinic, Rochester, MN 55905, USA
| | - Jens Bunt
- The University of Queensland, Queensland Brain Institute, Brisbane, QLD 4072, Australia
| | - Lydie Burglen
- Centre de référence des malformations et maladies congénitales du cervelet et Département de génétique et embryologie médicale, APHP, Sorbonne Université, Hôpital Armand Trousseau, 75012 Paris, France
| | - Philippe M Campeau
- Department of Pediatrics, University of Montreal and CHU Sainte-Justine, Montreal, QC, Canada
| | - Perrine Charles
- Département de Génétique, Centre de Référence Déficiences Intellectuelles de Causes Rares, Groupe Hospitalier Pitié Salpêtrière et Hôpital Trousseau, APHP, Sorbonne Université, Paris, France
| | - Brian H Y Chung
- Department of Paediatrics and Adolescent Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China
| | - Benjamin Cogné
- Service de Génétique Médicale, CHU Nantes, 9 quai Moncousu, 44093 Nantes Cedex 1, France; Université de Nantes, CNRS, INSERM, l'institut du thorax, 44000 Nantes, France
| | - Cynthia Curry
- Genetic Medicine, University of California San Francisco/Fresno, Fresno, CA 93701, USA
| | - Maria Daniela D'Agostino
- Division of Medical Genetics, Departments of Specialized Medicine and Human Genetics, McGill University, Montreal, QC, Canada
| | | | - Laurence Faivre
- Centre de référence Anomalies du Développement et Syndromes Malformatifs, INSERM UMR 1231 GAD, CHU de Dijon et Université de Bourgogne, Dijon, France
| | - Delphine Héron
- APHP, Département de Génétique, Groupe Hospitalier Pitié Salpêtrière, Paris, France
| | - A Micheil Innes
- Department of Medical Genetics, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Bertrand Isidor
- Service de Génétique Médicale, CHU Nantes, 9 quai Moncousu, 44093 Nantes Cedex 1, France; Université de Nantes, CNRS, INSERM, l'institut du thorax, 44000 Nantes, France
| | - Boris Keren
- APHP, Département de Génétique, Groupe Hospitalier Pitié Salpêtrière, Paris, France
| | - Amy Kimball
- Harvey Institute of Human Genetics, Greater Baltimore Medical Center, Baltimore, MD, USA
| | - Eric W Klee
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN 55905, USA; Department of Clinical Genomics, Mayo Clinic, Rochester, MN 55905, USA; Center for Individualized Medicine, Mayo Clinic, Rochester, MN 55905, USA; Department of Health Sciences Research, Mayo Clinic, Rochester, MN 55905, USA
| | - Paul Kuentz
- UMR-INSERM 1231 GAD, Génétique des Anomalies du développement, Université de Bourgogne Franche-Comté, Dijon, France
| | - Sébastien Küry
- Service de Génétique Médicale, CHU Nantes, 9 quai Moncousu, 44093 Nantes Cedex 1, France; Université de Nantes, CNRS, INSERM, l'institut du thorax, 44000 Nantes, France
| | | | - Ghayda Mirzaa
- Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, WA 98101, USA; Department of Pediatrics, University of Washington, Seattle, WA 98101, USA
| | - Cyril Mignot
- Département de Génétique, Centre de Référence Déficiences Intellectuelles de Causes Rares, Groupe Hospitalier Pitié Salpêtrière et Hôpital Trousseau, APHP, Sorbonne Université, Paris, France
| | - Noriko Miyake
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, Yokohama 236-0004, Japan
| | - Naomichi Matsumoto
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, Yokohama 236-0004, Japan
| | - Atsushi Fujita
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, Yokohama 236-0004, Japan
| | - Caroline Nava
- APHP, Département de Génétique, Groupe Hospitalier Pitié Salpêtrière, Paris, France
| | - Mathilde Nizon
- Service de Génétique Médicale, CHU Nantes, 9 quai Moncousu, 44093 Nantes Cedex 1, France; Université de Nantes, CNRS, INSERM, l'institut du thorax, 44000 Nantes, France
| | - Diana Rodriguez
- Centre de Référence Neurogénétique & Service de Neurologie Pédiatrique, APHP, Sorbonne Université, Hôpital Armand Trousseau, 75012 Paris, France
| | - Lot Snijders Blok
- Department of Human Genetics, Radboud University Medical Center, 6500 HB Nijmegen, the Netherlands
| | - Christel Thauvin-Robinet
- Centre de référence Déficience Intellectuelle, INSERM UMR 1231 GAD, CHU de Dijon et Université de Bourgogne, Dijon, France
| | - Julien Thevenon
- Centre de référence Anomalies du Développement et Syndromes Malformatifs, INSERM UMR 1231 GAD, CHU de Dijon et Université de Bourgogne, Dijon, France
| | - Marie Vincent
- Service de Génétique Médicale, CHU Nantes, 9 quai Moncousu, 44093 Nantes Cedex 1, France; Université de Nantes, CNRS, INSERM, l'institut du thorax, 44000 Nantes, France
| | | | - William Dobyns
- Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, WA 98101, USA; Departments of Pediatrics and Neurology, University of Washington, Seattle, WA 98101, USA
| | - Linda J Richards
- The University of Queensland, Queensland Brain Institute, Brisbane, QLD 4072, Australia; The University of Queensland, School of Biomedical Sciences, Brisbane 4072, QLD, Australia
| | - A James Barkovich
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Stephen N Floor
- Department of Cell and Tissue Biology, University of California, San Francisco, San Francisco, CA 94158, USA; Helen Diller Family Comprehensive Cancer Center, San Francisco, CA 94158, USA
| | - Debra L Silver
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710, USA; Department of Cell Biology, Duke University Medical Center, Durham, NC 27710, USA; Department of Neurobiology, Duke University Medical Center, Durham, NC 27710, USA; Duke Institute for Brain Sciences, Duke University, Durham, NC 27710, USA.
| | - Elliott H Sherr
- Department of Neurology, University of California, San Francisco, San Francisco, CA 94158, USA; Institute of Human Genetics and Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA 94158, USA.
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Räsch F, Weber R, Izaurralde E, Igreja C. 4E-T-bound mRNAs are stored in a silenced and deadenylated form. Genes Dev 2020; 34:847-860. [PMID: 32354837 PMCID: PMC7263148 DOI: 10.1101/gad.336073.119] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2019] [Accepted: 04/02/2020] [Indexed: 12/20/2022]
Abstract
Human 4E-T is an eIF4E-binding protein (4E-BP) present in processing (P)-bodies that represses translation and regulates decay of mRNAs destabilized by AU-rich elements and microRNAs (miRNAs). However, the underlying regulatory mechanisms are still unclear. Here, we show that upon mRNA binding 4E-T represses translation and promotes deadenylation via the recruitment of the CCR4-NOT deadenylase complex. The interaction with CCR4-NOT is mediated by previously uncharacterized sites in the middle region of 4E-T. Importantly, mRNA decapping and decay are inhibited by 4E-T and the deadenylated target is stored in a repressed form. Inhibition of mRNA decapping requires the interaction of 4E-T with the cap-binding proteins eIF4E/4EHP. We further show that regulation of decapping by 4E-T participates in mRNA repression by the miRNA effector protein TNRC6B and that 4E-T overexpression interferes with tristetraprolin (TTP)- and NOT1-mediated mRNA decay. Thus, we postulate that 4E-T modulates 5'-to-3' decay by swapping the fate of a deadenylated mRNA from complete degradation to storage. Our results provide insight into the mechanism of mRNA storage that controls localized translation and mRNA stability in P-bodies.
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Affiliation(s)
- Felix Räsch
- Department of Biochemistry, Max Planck Institute for Developmental Biology, D-72076 Tübingen, Germany
| | - Ramona Weber
- Department of Biochemistry, Max Planck Institute for Developmental Biology, D-72076 Tübingen, Germany
| | - Elisa Izaurralde
- Department of Biochemistry, Max Planck Institute for Developmental Biology, D-72076 Tübingen, Germany
| | - Cátia Igreja
- Department of Biochemistry, Max Planck Institute for Developmental Biology, D-72076 Tübingen, Germany
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20
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Translating neural stem cells to neurons in the mammalian brain. Cell Death Differ 2019; 26:2495-2512. [PMID: 31551564 DOI: 10.1038/s41418-019-0411-9] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2019] [Revised: 07/05/2019] [Accepted: 08/08/2019] [Indexed: 02/07/2023] Open
Abstract
The mammalian neocortex underlies our perception of sensory information, performance of motor activities, and higher-order cognition. During mammalian embryogenesis, radial glial precursor cells sequentially give rise to diverse populations of excitatory cortical neurons, followed by astrocytes and oligodendrocytes. A subpopulation of these embryonic neural precursors persists into adulthood as neural stem cells, which give rise to inhibitory interneurons and glia. Although the intrinsic mechanisms instructing the genesis of these distinct progeny have been well-studied, most work to date has focused on transcriptional, epigenetic, and cell-cycle control. Recent studies, however, have shown that posttranscriptional mechanisms also regulate the cell fate choices of transcriptionally primed neural precursors during cortical development. These mechanisms are mediated primarily by RNA-binding proteins and microRNAs that coordinately regulate mRNA translation, stability, splicing, and localization. Together, these findings point to an extensive network of posttranscriptional control and provide insight into both normal cortical development and disease. They also add another layer of complexity to brain development and raise important biological questions for future investigation.
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21
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Zahr SK, Yang G, Kazan H, Borrett MJ, Yuzwa SA, Voronova A, Kaplan DR, Miller FD. A Translational Repression Complex in Developing Mammalian Neural Stem Cells that Regulates Neuronal Specification. Neuron 2018; 97:520-537.e6. [PMID: 29395907 DOI: 10.1016/j.neuron.2017.12.045] [Citation(s) in RCA: 86] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Revised: 11/22/2017] [Accepted: 12/28/2017] [Indexed: 01/28/2023]
Abstract
The mechanisms instructing genesis of neuronal subtypes from mammalian neural precursors are not well understood. To address this issue, we have characterized the transcriptional landscape of radial glial precursors (RPs) in the embryonic murine cortex. We show that individual RPs express mRNA, but not protein, for transcriptional specifiers of both deep and superficial layer cortical neurons. Some of these mRNAs, including the superficial versus deep layer neuron transcriptional regulators Brn1 and Tle4, are translationally repressed by their association with the RNA-binding protein Pumilio2 (Pum2) and the 4E-T protein. Disruption of these repressive complexes in RPs mid-neurogenesis by knocking down 4E-T or Pum2 causes aberrant co-expression of deep layer neuron specification proteins in newborn superficial layer neurons. Thus, cortical RPs are transcriptionally primed to generate diverse types of neurons, and a Pum2/4E-T complex represses translation of some of these neuronal identity mRNAs to ensure appropriate temporal specification of daughter neurons.
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Affiliation(s)
- Siraj K Zahr
- Program in Neurosciences and Mental Health, Hospital for Sick Children, Toronto, ON M5G 1L7, Canada; Institute of Medical Science, University of Toronto, Toronto, ON M5G 1A8, Canada
| | - Guang Yang
- Program in Neurosciences and Mental Health, Hospital for Sick Children, Toronto, ON M5G 1L7, Canada
| | - Hilal Kazan
- Department of Computer Engineering, Antalya Bilim University, Antalya, Turkey
| | - Michael J Borrett
- Program in Neurosciences and Mental Health, Hospital for Sick Children, Toronto, ON M5G 1L7, Canada; Institute of Medical Science, University of Toronto, Toronto, ON M5G 1A8, Canada
| | - Scott A Yuzwa
- Program in Neurosciences and Mental Health, Hospital for Sick Children, Toronto, ON M5G 1L7, Canada
| | - Anastassia Voronova
- Program in Neurosciences and Mental Health, Hospital for Sick Children, Toronto, ON M5G 1L7, Canada
| | - David R Kaplan
- Program in Neurosciences and Mental Health, Hospital for Sick Children, Toronto, ON M5G 1L7, Canada; Institute of Medical Science, University of Toronto, Toronto, ON M5G 1A8, Canada; Department of Molecular Genetics, University of Toronto, Toronto, ON M5G 1A8, Canada
| | - Freda D Miller
- Program in Neurosciences and Mental Health, Hospital for Sick Children, Toronto, ON M5G 1L7, Canada; Institute of Medical Science, University of Toronto, Toronto, ON M5G 1A8, Canada; Department of Molecular Genetics, University of Toronto, Toronto, ON M5G 1A8, Canada; Department of Physiology, University of Toronto, Toronto, ON M5G 1A8, Canada.
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22
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Yuzwa SA, Borrett MJ, Innes BT, Voronova A, Ketela T, Kaplan DR, Bader GD, Miller FD. Developmental Emergence of Adult Neural Stem Cells as Revealed by Single-Cell Transcriptional Profiling. Cell Rep 2017; 21:3970-3986. [DOI: 10.1016/j.celrep.2017.12.017] [Citation(s) in RCA: 80] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Revised: 10/30/2017] [Accepted: 12/01/2017] [Indexed: 02/06/2023] Open
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23
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Baser A, Skabkin M, Martin-Villalba A. Neural Stem Cell Activation and the Role of Protein Synthesis. Brain Plast 2017; 3:27-41. [PMID: 29765858 PMCID: PMC5928545 DOI: 10.3233/bpl-160038] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Adult neural stem cells are generated at embryonic stages by entering a quiescent state that allows their retention into adulthood and thereby maintenance of life-long brain homeostasis. Thus, a tight balance between the quiescence and activation state is instrumental to meet the brain demands for a specific cell type at the correct numbers, at a given time and position. Protein synthesis is the most energy-consuming process within the cell and, not surprisingly, it occurs at low rates in quiescent stem cells. This way quiescent cells adjust to energy constraints and avoid their premature depletion. Stem cell activation is characterized by upregulation of protein synthesis followed by cell division and differentiation. The role of such upregulation as causative or rather a consequence of the activation remains elusive. Here we summarize recent findings connecting stem cell activation to the regulation of protein synthesis, particularly focusing on embryonic and adult neural stem cells of the ventricular zone.
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Affiliation(s)
- Avni Baser
- Molecular Neurobiology, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Maxim Skabkin
- Molecular Neurobiology, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Ana Martin-Villalba
- Molecular Neurobiology, German Cancer Research Center (DKFZ), Heidelberg, Germany
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24
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Lennox AL, Mao H, Silver DL. RNA on the brain: emerging layers of post-transcriptional regulation in cerebral cortex development. WILEY INTERDISCIPLINARY REVIEWS-DEVELOPMENTAL BIOLOGY 2017; 7. [PMID: 28837264 DOI: 10.1002/wdev.290] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Revised: 07/19/2017] [Accepted: 07/20/2017] [Indexed: 12/11/2022]
Abstract
Embryonic development is a critical period during which neurons of the brain are generated and organized. In the developing cerebral cortex, this requires complex processes of neural progenitor proliferation, neuronal differentiation, and migration. Each step relies upon highly regulated control of gene expression. In particular, RNA splicing, stability, localization, and translation have emerged as key post-transcriptional regulatory nodes of mouse corticogenesis. Trans-regulators of RNA metabolism, including microRNAs (miRs) and RNA-binding proteins (RBPs), orchestrate diverse steps of cortical development. These trans-factors function either individually or cooperatively to influence RNAs, often of similar classes, termed RNA regulons. New technological advances raise the potential for an increasingly sophisticated understanding of post-transcriptional control in the developing neocortex. Many RNA-binding factors are also implicated in neurodevelopmental diseases of the cortex. Therefore, elucidating how RBPs and miRs converge to influence mRNA expression in progenitors and neurons will give valuable insights into mechanisms of cortical development and disease. WIREs Dev Biol 2018, 7:e290. doi: 10.1002/wdev.290 This article is categorized under: Gene Expression and Transcriptional Hierarchies > Regulatory RNA Nervous System Development > Vertebrates: Regional Development Adult Stem Cells, Tissue Renewal, and Regeneration > Stem Cells and Disease.
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Affiliation(s)
- Ashley L Lennox
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC, USA
| | - Hanqian Mao
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC, USA.,Department of Cell Biology and Physiology, University of North Carolina, Chapel Hill, NC, USA
| | - Debra L Silver
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC, USA.,Department of Cell Biology, Duke University Medical Center, Durham, NC, USA.,Department of Neurobiology, Duke University Medical Center, Durham, NC, USA
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25
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Pilaz LJ, Silver DL. Moving messages in the developing brain-emerging roles for mRNA transport and local translation in neural stem cells. FEBS Lett 2017; 591:1526-1539. [PMID: 28304078 DOI: 10.1002/1873-3468.12626] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2017] [Revised: 03/06/2017] [Accepted: 03/11/2017] [Indexed: 11/10/2022]
Abstract
The mammalian cerebral cortex is a complex brain structure integral to our higher cognition. During embryonic cortical development, radial glial progenitors (RGCs) produce neurons and serve as physical structures for migrating neurons. Recent discoveries highlight new roles for RNA localization and local translation in RGCs, both at the cell body and at distal structures called basal endfeet. By implementing technologies from the field of RNA research to brain development, investigators can manipulate RNA-binding proteins as well as visualize single-molecule RNAs, live movement of mRNAs and their binding proteins, and translation. Going forward, these studies establish a framework for investigating how post-transcriptional RNA regulation helps shape RGC function and triggers neurodevelopmental diseases.
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Affiliation(s)
- Louis-Jan Pilaz
- Department of Molecular Genetics and Microbiology, Regeneration Next, Duke University Medical Center, Durham, NC, USA
| | - Debra L Silver
- Department of Molecular Genetics and Microbiology, Regeneration Next, Duke University Medical Center, Durham, NC, USA.,Department of Cell Biology, Duke University Medical Center, Durham, NC, USA.,Department of Neurobiology, Duke University Medical Center, Durham, NC, USA.,Duke Institute for Brain Sciences, Duke University Medical Center, Durham, NC, USA
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26
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Kamenska A, Simpson C, Vindry C, Broomhead H, Bénard M, Ernoult-Lange M, Lee BP, Harries LW, Weil D, Standart N. The DDX6-4E-T interaction mediates translational repression and P-body assembly. Nucleic Acids Res 2016; 44:6318-34. [PMID: 27342281 PMCID: PMC5291280 DOI: 10.1093/nar/gkw565] [Citation(s) in RCA: 75] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Revised: 06/10/2016] [Accepted: 06/14/2016] [Indexed: 12/13/2022] Open
Abstract
4E-Transporter binds eIF4E via its consensus sequence YXXXXLΦ, shared with eIF4G, and is a nucleocytoplasmic shuttling protein found enriched in P-(rocessing) bodies. 4E-T inhibits general protein synthesis by reducing available eIF4E levels. Recently, we showed that 4E-T bound to mRNA however represses its translation in an eIF4E-independent manner, and contributes to silencing of mRNAs targeted by miRNAs. Here, we address further the mechanism of translational repression by 4E-T by first identifying and delineating the interacting sites of its major partners by mass spectrometry and western blotting, including DDX6, UNR, unrip, PAT1B, LSM14A and CNOT4. Furthermore, we document novel binding between 4E-T partners including UNR-CNOT4 and unrip-LSM14A, altogether suggesting 4E-T nucleates a complex network of RNA-binding protein interactions. In functional assays, we demonstrate that joint deletion of two short conserved motifs that bind UNR and DDX6 relieves repression of 4E-T-bound mRNA, in part reliant on the 4E-T-DDX6-CNOT1 axis. We also show that the DDX6-4E-T interaction mediates miRNA-dependent translational repression and de novo P-body assembly, implying that translational repression and formation of new P-bodies are coupled processes. Altogether these findings considerably extend our understanding of the role of 4E-T in gene regulation, important in development and neurogenesis.
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Affiliation(s)
- Anastasiia Kamenska
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge CB21QW, UK
| | - Clare Simpson
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge CB21QW, UK
| | - Caroline Vindry
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge CB21QW, UK
| | - Helen Broomhead
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge CB21QW, UK
| | - Marianne Bénard
- Sorbonne Universités, UPMC, CNRS, IBPS, Developmental Biology Laboratory, 75005 Paris, France
| | - Michèle Ernoult-Lange
- Sorbonne Universités, UPMC, CNRS, IBPS, Developmental Biology Laboratory, 75005 Paris, France
| | - Benjamin P Lee
- Institute of Biomedical and Clinical Sciences, University of Exeter Medical School, Barrack Road, Exeter EX2 5DW
| | - Lorna W Harries
- Institute of Biomedical and Clinical Sciences, University of Exeter Medical School, Barrack Road, Exeter EX2 5DW
| | - Dominique Weil
- Sorbonne Universités, UPMC, CNRS, IBPS, Developmental Biology Laboratory, 75005 Paris, France
| | - Nancy Standart
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge CB21QW, UK
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27
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Fernández-Alvarez AJ, Pascual ML, Boccaccio GL, Thomas MG. Smaug variants in neural and non-neuronal cells. Commun Integr Biol 2016; 9:e1139252. [PMID: 27195061 PMCID: PMC4857778 DOI: 10.1080/19420889.2016.1139252] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Revised: 01/02/2016] [Accepted: 01/04/2016] [Indexed: 10/25/2022] Open
Abstract
Mammalian Smaug1/Samd4a is an mRNA regulator involved in synapse plasticity and additional non-neuronal functions. Here we analyzed the expression of Smaug1/Samd4a variants and Smaug2/Samd4b in primary hippocampal neurons and non-neuronal cell lines. We found that multiple Smaug proteins are present in several mammalian cell lines, including a canonical full length Smaug1, a Smaug1 variant that lacks the third exon, termed ΔEIII, and Smaug2, the product of a highly homologous gene. These three major isoforms are expressed differentially along neuron development and form cytosolic bodies when transfected in cell lines. By using luciferase reporters, we found that the ΔEIII isoform, which lacks 10 amino acids in the sterile α motif involved in RNA binding, shows a RNA-binding capacity and repressor activity comparable to that of the full length Smaug1. These observations are an important groundwork for molecular studies of the Smaug post-transcriptional pathway, which is relevant to neuron development, mitochondrial function and muscle physiology in health and disease.
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Affiliation(s)
- Ana Julia Fernández-Alvarez
- Fundación Instituto Leloir, Buenos Aires, Argentina; Instituto de Investigaciones Bioquímicas Buenos Aires-Consejo Nacional de Investigaciones Científicas y Tecnológicas, Buenos Aires, Argentina
| | - Malena Lucía Pascual
- Fundación Instituto Leloir, Buenos Aires, Argentina; Instituto de Investigaciones Bioquímicas Buenos Aires-Consejo Nacional de Investigaciones Científicas y Tecnológicas, Buenos Aires, Argentina; Facultad de Ciencias Exactas y Naturales, University of Buenos Aires, Buenos Aires, Argentina
| | - Graciela Lidia Boccaccio
- Fundación Instituto Leloir, Buenos Aires, Argentina; Instituto de Investigaciones Bioquímicas Buenos Aires-Consejo Nacional de Investigaciones Científicas y Tecnológicas, Buenos Aires, Argentina; Facultad de Ciencias Exactas y Naturales, University of Buenos Aires, Buenos Aires, Argentina
| | - María Gabriela Thomas
- Fundación Instituto Leloir, Buenos Aires, Argentina; Instituto de Investigaciones Bioquímicas Buenos Aires-Consejo Nacional de Investigaciones Científicas y Tecnológicas, Buenos Aires, Argentina
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28
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Thomas MG, Boccaccio GL. Novel mRNA-silencing bodies at the synapse: A never-ending story. Commun Integr Biol 2016; 9:e1139251. [PMID: 27195060 PMCID: PMC4857779 DOI: 10.1080/19420889.2016.1139251] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Revised: 01/02/2016] [Accepted: 01/04/2016] [Indexed: 01/08/2023] Open
Abstract
Several cellular responses depend on translational regulation and in most cases, this involves the formation of cytoplasmic granules that contain repressed mRNAs. In neurons, numerous mRNAs travel along dendrites to be locally regulated upon synapse activity and we have recently shown that the exoribonuclease XRN1 forms dynamic aggregates at the post synapse that respond to specific stimuli.1 These foci were termed SX-bodies and are distinct from stress granules (SGs), processing bodies (PBs) and other RNA granules previously described. Together with Smaug1-foci and FMRP-granules, the SX-bodies contribute to dynamically shape the transcriptome available for translation at the post-synapse.
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Affiliation(s)
- María Gabriela Thomas
- Fundación Instituto Leloir, Buenos Aires, Argentina; Instituto de Investigaciones Bioquímicas Buenos Aires-Consejo Nacional de Investigaciones Científicas y Tecnológicas, Buenos Aires, Argentina
| | - Graciela Lidia Boccaccio
- Fundación Instituto Leloir, Buenos Aires, Argentina; Instituto de Investigaciones Bioquímicas Buenos Aires-Consejo Nacional de Investigaciones Científicas y Tecnológicas, Buenos Aires, Argentina; Facultad de Ciencias Exactas y Naturales, University of Buenos Aires, Buenos Aires, Argentina
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