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Parkins EV, Gross C. Small Differences and Big Changes: The Many Variables of MicroRNA Expression and Function in the Brain. J Neurosci 2024; 44:e0365242024. [PMID: 39111834 PMCID: PMC11308354 DOI: 10.1523/jneurosci.0365-24.2024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2024] [Revised: 05/15/2024] [Accepted: 05/23/2024] [Indexed: 08/10/2024] Open
Abstract
MicroRNAs are emerging as crucial regulators within the complex, dynamic environment of the synapse, and they offer a promising new avenue for the treatment of neurological disease. These small noncoding RNAs modify gene expression in several ways, including posttranscriptional modulation via binding to complementary and semicomplementary sites on target mRNAs. This rapid, finely tuned regulation of gene expression is essential to meet the dynamic demands of the synapse. Here, we provide a detailed review of the multifaceted world of synaptic microRNA regulation. We discuss the many mechanisms by which microRNAs regulate gene expression at the synapse, particularly in the context of neuronal plasticity. We also describe the various factors, such as age, sex, and neurological disease, that can influence microRNA expression and activity in neurons. In summary, microRNAs play a crucial role in the intricate and quickly changing functional requirements of the synapse, and context is essential in the study of microRNAs and their potential therapeutic applications.
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Affiliation(s)
- Emma V Parkins
- University of Cincinnati Neuroscience Graduate Program, Cincinnati, Ohio 45229
- Division of Neurology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio 45229
| | - Christina Gross
- University of Cincinnati Neuroscience Graduate Program, Cincinnati, Ohio 45229
- Division of Neurology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio 45229
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio 45229
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Bitarafan S, Pybus AF, Rivera Moctezuma FG, Adibi M, Franklin TC, Singer AC, Wood LB. Frequency and duration of sensory flicker controls astrocyte and neuron specific transcriptional profiles in 5xFAD mice. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.20.594705. [PMID: 38826251 PMCID: PMC11142106 DOI: 10.1101/2024.05.20.594705] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2024]
Abstract
Background Current clinical trials are investigating gamma frequency sensory stimulation as a potential therapeutic strategy for Alzheimer's disease, yet we lack a comprehensive picture of the effects of this stimulation on multiple aspects of brain function. While most prior research has focused on gamma frequency sensory stimulation, we previously showed that exposing mice to visual flickering stimulation increased MAPK and NFκB signaling in the visual cortex in a manner dependent on duration and frequency of sensory stimulation exposure. Because these pathways control multiple neuronal and glial functions and are differentially activated based on the duration and frequency of flicker stimulation, we aimed to define the transcriptional effects of different frequencies and durations of flicker stimulation on multiple brain functions. Methods We exposed 5xFAD mice to different frequencies of audio/visual flicker stimulation (constant light, 10Hz, 20Hz, 40Hz) for durations of 0.5hr, 1hr, or 4hr, then used bulk RNAseq to profile transcriptional changes within the visual cortex and hippocampus tissues. Using weighted gene co-expression network analysis, we identified modules of co-expressed genes controlled by frequency and/or duration of stimulation. Results Within the visual cortex, we found that all stimulation frequencies caused fast activation of a module of immune genes within 1hr and slower suppression of synaptic genes after 4hrs of stimulation. Interestingly, all frequencies of stimulation led to slow suppression of astrocyte specific gene sets, while activation of neuronal gene sets was frequency and duration specific. In contrast, in the hippocampus, immune and synaptic modules were suppressed based on the frequency of stimulation. Specifically,10Hz activated a module of genes associated with mitochondrial function, metabolism, and synaptic translation while 10Hz rapidly suppressed a module of genes linked to neurotransmitter activity. Conclusion Collectively, our data indicate that the frequency and duration of flicker stimulation controls immune, neuronal, and metabolic genes in multiple regions of the brain affected by Alzheimer's disease. Flicker stimulation may thus represent a potential therapeutic strategy that can be tuned based on the brain region and the specific cellular process to be modulated.
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Zolboot N, Xiao Y, Du JX, Ghanem MM, Choi SY, Junn MJ, Zampa F, Huang Z, MacRae IJ, Lippi G. MicroRNAs are necessary for the emergence of Purkinje cell identity. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.09.28.560023. [PMID: 37808721 PMCID: PMC10557743 DOI: 10.1101/2023.09.28.560023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/10/2023]
Abstract
Brain computations are dictated by the unique morphology and connectivity of neuronal subtypes, features established by closely timed developmental events. MicroRNAs (miRNAs) are critical for brain development, but current technologies lack the spatiotemporal resolution to determine how miRNAs instruct the steps leading to subtype identity. Here, we developed new tools to tackle this major gap. Fast and reversible miRNA loss-of-function revealed that miRNAs are necessary for cerebellar Purkinje cell (PC) differentiation, which previously appeared miRNA-independent, and resolved distinct miRNA critical windows in PC dendritogenesis and climbing fiber synaptogenesis, key determinants of PC identity. To identify underlying mechanisms, we generated a mouse model, which enables precise mapping of miRNAs and their targets in rare cell types. With PC-specific maps, we found that the PC-enriched miR-206 drives exuberant dendritogenesis and modulates synaptogenesis. Our results showcase vastly improved approaches for dissecting miRNA function and reveal that many critical miRNA mechanisms remain largely unexplored. Highlights Fast miRNA loss-of-function with T6B impairs postnatal Purkinje cell developmentReversible T6B reveals critical miRNA windows for dendritogenesis and synaptogenesisConditional Spy3-Ago2 mouse line enables miRNA-target network mapping in rare cellsPurkinje cell-enriched miR-206 regulates its unique dendritic and synaptic morphology.
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Soutschek M, Schratt G. Non-coding RNA in the wiring and remodeling of neural circuits. Neuron 2023:S0896-6273(23)00341-0. [PMID: 37230080 DOI: 10.1016/j.neuron.2023.04.031] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Revised: 04/25/2023] [Accepted: 04/26/2023] [Indexed: 05/27/2023]
Abstract
The brain constantly adapts to changes in the environment, a capability that underlies memory and behavior. Long-term adaptations require the remodeling of neural circuits that are mediated by activity-dependent alterations in gene expression. Over the last two decades, it has been shown that the expression of protein-coding genes is significantly regulated by a complex layer of non-coding RNA (ncRNA) interactions. The aim of this review is to summarize recent discoveries regarding the functional involvement of ncRNAs during different stages of neural circuit development, activity-dependent circuit remodeling, and circuit maladapations underlying neurological and neuropsychiatric disorders. In addition to the intensively studied microRNA (miRNA) family, we focus on more recently added ncRNA classes, such as long ncRNAs (lncRNAs) and circular RNAs (circRNAs), and discuss the complex regulatory interactions between these different RNAs. We conclude by discussing the potential relevance of ncRNAs for cell-type and -state-specific regulation in the context of memory formation, the evolution of human cognitive abilities, and the development of new diagnostic and therapeutic tools in brain disorders.
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Affiliation(s)
- Michael Soutschek
- Laboratory of Systems Neuroscience, Institute for Neuroscience, Department of Health Science and Technology, Swiss Federal Institute of Technology ETH, 8057 Zurich, Switzerland
| | - Gerhard Schratt
- Laboratory of Systems Neuroscience, Institute for Neuroscience, Department of Health Science and Technology, Swiss Federal Institute of Technology ETH, 8057 Zurich, Switzerland.
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Vasiliev GV, Ovchinnikov VY, Lisachev PD, Bondar NP, Grinkevich LN. The Expression of miRNAs Involved in Long-Term Memory Formation in the CNS of the Mollusk Helix lucorum. Int J Mol Sci 2022; 24:ijms24010301. [PMID: 36613744 PMCID: PMC9820140 DOI: 10.3390/ijms24010301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Revised: 12/15/2022] [Accepted: 12/21/2022] [Indexed: 12/28/2022] Open
Abstract
Mollusks are unique animals with a relatively simple central nervous system (CNS) containing giant neurons with identified functions. With such simple CNS, mollusks yet display sufficiently complex behavior, thus ideal for various studies of behavioral processes, including long-term memory (LTM) formation. For our research, we use the formation of the fear avoidance reflex in the terrestrial mollusk Helix lucorum as a learning model. We have shown previously that LTM formation in Helix requires epigenetic modifications of histones leading to both activation and inactivation of the specific genes. It is known that microRNAs (miRNAs) negatively regulate the expression of genes; however, the role of miRNAs in behavioral regulation has been poorly investigated. Currently, there is no miRNAs sequencing data being published on Helix lucorum, which makes it impossible to investigate the role of miRNAs in the memory formation of this mollusk. In this study, we have performed sequencing and comparative bioinformatics analysis of the miRNAs from the CNS of Helix lucorum. We have identified 95 different microRNAs, including microRNAs belonging to the MIR-9, MIR-10, MIR-22, MIR-124, MIR-137, and MIR-153 families, known to be involved in various CNS processes of vertebrates and other species, particularly, in the fear behavior and LTM. We have shown that in the CNS of Helix lucorum MIR-10 family (26 miRNAs) is the most representative one, including Hlu-Mir-10-S5-5p and Hlu-Mir-10-S9-5p as top hits. Moreover, we have shown the involvement of the MIR-10 family in LTM formation in Helix. The expression of 17 representatives of MIR-10 differentially changes during different periods of LTM consolidation in the CNS of Helix. In addition, using comparative analysis of microRNA expression upon learning in normal snails and snails with deficient learning abilities with dysfunction of the serotonergic system, we identified a number of microRNAs from several families, including MIR-10, which expression changes only in normal animals. The obtained data can be used for further fundamental and applied behavioral research.
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Affiliation(s)
- Gennady V. Vasiliev
- The Federal Research Center Institute of Cytology and Genetics, Siberian Branch, Russian Academy of Sciences, 10 Lavrentiev Avenue, Novosibirsk 630090, Russia
| | - Vladimir Y. Ovchinnikov
- The Federal Research Center Institute of Cytology and Genetics, Siberian Branch, Russian Academy of Sciences, 10 Lavrentiev Avenue, Novosibirsk 630090, Russia
| | - Pavel D. Lisachev
- Federal Research Center for Information and Computational Technologies, 6 Lavrentiev Avenue, Novosibirsk 630090, Russia
| | - Natalia P. Bondar
- The Federal Research Center Institute of Cytology and Genetics, Siberian Branch, Russian Academy of Sciences, 10 Lavrentiev Avenue, Novosibirsk 630090, Russia
| | - Larisa N. Grinkevich
- The Federal State Budget Scientific Institution Pavlov Institute of Physiology, Russian Academy of Sciences, 6 nab. Makarova, St. Petersburg 199034, Russia
- Correspondence:
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Noyes NC, Phan A, Davis RL. Memory suppressor genes: Modulating acquisition, consolidation, and forgetting. Neuron 2021; 109:3211-3227. [PMID: 34450024 PMCID: PMC8542634 DOI: 10.1016/j.neuron.2021.08.001] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Revised: 07/15/2021] [Accepted: 07/30/2021] [Indexed: 02/06/2023]
Abstract
The brain has a remarkable but underappreciated capacity to limit memory formation and expression. The term "memory suppressor gene" was coined in 1998 as an attempt to explain emerging reports that some genes appeared to limit memory. At that time, only a handful of memory suppressor genes were known, and they were understood to work by limiting cAMP-dependent consolidation. In the intervening decades, almost 100 memory suppressor genes with diverse functions have been discovered that affect not only consolidation but also acquisition and forgetting. Here we highlight the surprising extent to which biological limits are placed on memory formation through reviewing the literature on memory suppressor genes. In this review, we present memory suppressors within the framework of their actions on different memory operations: acquisition, consolidation, and forgetting. This is followed by a discussion of the reasons why there may be a biological need to limit memory formation.
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Affiliation(s)
- Nathaniel C Noyes
- Department of Neuroscience, Scripps Research Institute Florida, Jupiter, FL 33458, USA
| | - Anna Phan
- Department of Biological Sciences, University of Alberta, 11355 Saskatchewan Drive, Edmonton, AB T6G 2E9, Canada
| | - Ronald L Davis
- Department of Neuroscience, Scripps Research Institute Florida, Jupiter, FL 33458, USA.
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Grinkevich LN. The role of microRNAs in learning and long-term memory. Vavilovskii Zhurnal Genet Selektsii 2020; 24:885-896. [PMID: 35088002 PMCID: PMC8763713 DOI: 10.18699/vj20.687] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Revised: 10/11/2020] [Accepted: 10/15/2020] [Indexed: 01/10/2023] Open
Abstract
The mechanisms of long-term memory formation and ways to improve it (in the case of its impairment) remain an extremely difficult problem yet to be solved. Over the recent years, much attention has been
paid to microRNAs in this regard. MicroRNAs are unique endogenous non-coding RNAs about 22 nucleotides in
length; each can regulate translation of hundreds of messenger RNA targets, thereby controlling entire gene networks. MicroRNAs are widely represented in the central nervous system. A large number of studies are currently
being conducted to investigate the role of microRNAs in the brain functioning. A number of microRNAs have
been shown to be involved in the process of synaptic plasticity, as well as in the long-term memory formation.
Disruption of microRNA biogenesis leads to significant cognitive dysfunctions. Moreover, impaired microRNA
biogenesis is one of the causes of the pathogenesis of mental disorders, neurodegenerative illnesses and senile
dementia, which are often accompanied by deterioration in the learning ability and by memory impairment.
Optimistic predictions are made that microRNAs can be used as targets for therapeutic treatment and for diagnosing the above pathologies. The importance of applications related to microRNAs significantly raises interest
in studying their functions in the brain. Thus, this review is focused on the role of microRNAs in cognitive processes. It describes microRNA biogenesis and the role of miRNAs in the regulation of gene expression, as well
as the latest achievements in studying the functional role of microRNAs in learning and in long-term memory
formation, depending on the activation or inhibition of their expression. The review presents summarized data
on the effect of impaired microRNA biogenesis on long-term memory formation, including those associated with
sleep deprivation. In addition, analysis is provided of the current literature related to the prospects of improving
cognitive processes by influencing microRNA biogenesis via the use of CRISPR/Cas9 technologies and active
mental and physical exercises.
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Affiliation(s)
- L. N. Grinkevich
- Pavlov Institute of Physiology of the Russian Academy of Sciences
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8
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Single-cell RNA-seq analysis revealed long-lasting adverse effects of tamoxifen on neurogenesis in prenatal and adult brains. Proc Natl Acad Sci U S A 2020; 117:19578-19589. [PMID: 32727894 DOI: 10.1073/pnas.1918883117] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
The CreER/LoxP system is widely accepted to track neural lineages and study gene functions upon tamoxifen (TAM) administration. We have observed that prenatal TAM treatment caused high rates of delayed delivery and fetal mortality. This substance could produce undesired results, leading to data misinterpretation. Here, we report that administration of TAM during early stages of cortical neurogenesis promoted precocious neural differentiation, while it inhibited neural progenitor cell (NPC) proliferation. The TAM-induced inhibition of NPC proliferation led to deficits in cortical neurogenesis, dendritic morphogenesis, synaptic formation, and cortical patterning in neonatal and postnatal offspring. Mechanistically, by employing single-cell RNA-sequencing (scRNA-seq) analysis combined with in vivo and in vitro assays, we show TAM could exert these drastic effects mainly through dysregulating the Wnt-Dmrta2 signaling pathway. In adult mice, administration of TAM significantly attenuated NPC proliferation in both the subventricular zone and the dentate gyrus. This study revealed the cellular and molecular mechanisms for the adverse effects of TAM on corticogenesis, suggesting that care must be taken when using the TAM-induced CreER/LoxP system for neural lineage tracing and genetic manipulation studies in both embryonic and adult brains.
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He F, Wu H, Zhou L, Lin Q, Cheng Y, Sun YE. Tet2-mediated epigenetic drive for astrocyte differentiation from embryonic neural stem cells. Cell Death Discov 2020; 6:30. [PMID: 32377393 PMCID: PMC7190615 DOI: 10.1038/s41420-020-0264-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Revised: 04/04/2020] [Accepted: 04/07/2020] [Indexed: 12/15/2022] Open
Abstract
DNA methylation and demethylation at CpG di-nucleotide sites plays important roles in cell fate specification of neural stem cells (NSCs). We have previously reported that DNA methyltransferases, Dnmt1and Dnmt3a, serve to suppress precocious astrocyte differentiation from NSCs via methylation of astroglial lineage genes. However, whether active DNA demethylase also participates in astrogliogenesis remains undetermined. In this study, we discovered that a Ten-eleven translocation (Tet) protein, Tet2, which was critically involved in active DNA demethylation through oxidation of 5-Methylcytosine (5mC), drove astrocyte differentiation from NSCs by demethylation of astroglial lineage genes including Gfap. Moreover, we found that an NSC-specific bHLH transcription factor Olig2 was an upstream inhibitor for Tet2 expression through direct association with the Tet2 promoter, and indirectly inhibited astrocyte differentiation. Our research not only revealed a brand-new function of Tet2 to promote NSC differentiation into astrocytes, but also a novel mechanism for Olig2 to inhibit astrocyte formation.
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Affiliation(s)
- Fei He
- Shanghai Institute of Stem Cell Research and Clinical Translation, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, 200092 China
| | - Hao Wu
- Department of Genetics, University of Pennsylvania, Philadelphia, PA 19104 USA
- Penn Epigenetics Institute, University of Pennsylvania, Philadelphia, PA 19104 USA
| | - Liqiang Zhou
- Shanghai Institute of Stem Cell Research and Clinical Translation, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, 200092 China
| | - Quan Lin
- Department of Psychiatry and Biobehavioral Sciences, Intellectual Development and Disabilities Research Center, David Geffen School of Medicine, University of California, Los Angeles, CA 90095 USA
| | - Yin Cheng
- Department of Psychiatry and Biobehavioral Sciences, Intellectual Development and Disabilities Research Center, David Geffen School of Medicine, University of California, Los Angeles, CA 90095 USA
| | - Yi E. Sun
- Shanghai Institute of Stem Cell Research and Clinical Translation, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, 200092 China
- Department of Psychiatry and Biobehavioral Sciences, Intellectual Development and Disabilities Research Center, David Geffen School of Medicine, University of California, Los Angeles, CA 90095 USA
- Collaborative Innovation Center for Brain Science, Tongji University, Shanghai, 200092 China
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10
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Humphries BA, Wang Z, Yang C. MicroRNA Regulation of the Small Rho GTPase Regulators-Complexities and Opportunities in Targeting Cancer Metastasis. Cancers (Basel) 2020; 12:E1092. [PMID: 32353968 PMCID: PMC7281527 DOI: 10.3390/cancers12051092] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Revised: 04/24/2020] [Accepted: 04/25/2020] [Indexed: 02/07/2023] Open
Abstract
The small Rho GTPases regulate important cellular processes that affect cancer metastasis, such as cell survival and proliferation, actin dynamics, adhesion, migration, invasion and transcriptional activation. The Rho GTPases function as molecular switches cycling between an active GTP-bound and inactive guanosine diphosphate (GDP)-bound conformation. It is known that Rho GTPase activities are mainly regulated by guanine nucleotide exchange factors (RhoGEFs), GTPase-activating proteins (RhoGAPs), GDP dissociation inhibitors (RhoGDIs) and guanine nucleotide exchange modifiers (GEMs). These Rho GTPase regulators are often dysregulated in cancer; however, the underlying mechanisms are not well understood. MicroRNAs (miRNAs), a large family of small non-coding RNAs that negatively regulate protein-coding gene expression, have been shown to play important roles in cancer metastasis. Recent studies showed that miRNAs are capable of directly targeting RhoGAPs, RhoGEFs, and RhoGDIs, and regulate the activities of Rho GTPases. This not only provides new evidence for the critical role of miRNA dysregulation in cancer metastasis, it also reveals novel mechanisms for Rho GTPase regulation. This review summarizes recent exciting findings showing that miRNAs play important roles in regulating Rho GTPase regulators (RhoGEFs, RhoGAPs, RhoGDIs), thus affecting Rho GTPase activities and cancer metastasis. The potential opportunities and challenges for targeting miRNAs and Rho GTPase regulators in treating cancer metastasis are also discussed. A comprehensive list of the currently validated miRNA-targeting of small Rho GTPase regulators is presented as a reference resource.
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Affiliation(s)
- Brock A. Humphries
- Center for Molecular Imaging, Department of Radiology, University of Michigan, 109 Zina Pitcher Place, Ann Arbor, MI 48109, USA
| | - Zhishan Wang
- Department of Toxicology and Cancer Biology, College of Medicine, University of Kentucky, 1095 V A Drive, Lexington, KY 40536, USA;
| | - Chengfeng Yang
- Department of Toxicology and Cancer Biology, College of Medicine, University of Kentucky, 1095 V A Drive, Lexington, KY 40536, USA;
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Gupta SS, van Huis MA. Strained epitaxial interfaces of metal (Pd, Pt, Au) overlayers on nonpolar CdS ([Formula: see text]) surfaces from first-principles. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2019; 31:505001. [PMID: 31389344 DOI: 10.1088/1361-648x/ab3919] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The depositions of (1 1 1) and (1 0 0) overlayers of Pd, Pt and Au on the CdS (1 0 [Formula: see text] 0) surface are studied within epitaxial mismatches of 6%-7%, using spin-polarized density functional theory. For both compressively strained and tensile-strained interfaces, the (1 0 0) overlayers were found to be thermodynamically more stable owing to better interfacial matching, and higher surface uncoordination resulting in higher reactivity. Pt(1 1 1) exhibits slip dislocations even for five-atomic-layer thick Pt slabs. Along with the leading metal-S interaction, the interfacial charge transfers indicate a weak metal-Cd interaction which decreases in strength in the order Pd > Pt ∼ Au. For the same substrate area, the accumulation of electronic charge for Pt overlayers is ∼1.5-2 times larger than that of Pd and Au. The n-type Schottky barriers of Au overlayers with the minimum mismatch are within 0.1 eV of the predictions of Schottky-Mott rule, indicating a relatively ideal, scantily reactive interface structure. This is in clear contrast to the Pt epitaxial overlayers which deviate by 0.6-0.8 eV.
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Affiliation(s)
- S S Gupta
- Soft Condensed Matter, Debye Institute for Nanomaterials Science, Utrecht University, Princetonplein 5, 3584 CC Utrecht, The Netherlands
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12
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Martineau FS, Sahu S, Plantier V, Buhler E, Schaller F, Fournier L, Chazal G, Kawasaki H, Represa A, Watrin F, Manent JB. Correct Laminar Positioning in the Neocortex Influences Proper Dendritic and Synaptic Development. Cereb Cortex 2019; 28:2976-2990. [PMID: 29788228 PMCID: PMC6041803 DOI: 10.1093/cercor/bhy113] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Indexed: 01/28/2023] Open
Abstract
The neocortex is a 6-layered laminated structure with a precise anatomical and functional organization ensuring proper function. Laminar positioning of cortical neurons, as determined by termination of neuronal migration, is a key determinant of their ability to assemble into functional circuits. However, the exact contribution of laminar placement to dendrite morphogenesis and synapse formation remains unclear. Here we manipulated the laminar position of cortical neurons by knocking down doublecortin (Dcx), a crucial effector of migration, and show that misplaced neurons fail to properly form dendrites, spines, and functional glutamatergic and GABAergic synapses. We further show that knocking down Dcx in properly positioned neurons induces similar but milder defects, suggesting that the laminar misplacement is the primary cause of altered neuronal development. Thus, the specific laminar environment of their fated layers is crucial for the maturation of cortical neurons, and influences their functional integration into developing cortical circuits.
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Affiliation(s)
| | - Surajit Sahu
- INMED, Aix-Marseille University, INSERM U901, Marseille, France
| | | | | | | | | | | | - Hiroshi Kawasaki
- Department of Medical Neuroscience, Graduate School of Medical Sciences, Kanazawa University, Ishikawa, Japan
| | - Alfonso Represa
- INMED, Aix-Marseille University, INSERM U901, Marseille, France
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Reddy AP, Ravichandran J, Carkaci-Salli N. Neural regeneration therapies for Alzheimer's and Parkinson's disease-related disorders. Biochim Biophys Acta Mol Basis Dis 2019; 1866:165506. [PMID: 31276770 DOI: 10.1016/j.bbadis.2019.06.020] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Revised: 06/24/2019] [Accepted: 06/26/2019] [Indexed: 12/20/2022]
Abstract
Neurodegenerative diseases are devastating mental illnesses without a cure. Alzheimer's disease (AD) characterized by memory loss, multiple cognitive impairments, and changes in personality and behavior. Although tremendous progress has made in understanding the basic biology in disease processes in AD and PD, we still do not have early detectable biomarkers for these diseases. Just in the United States alone, federal and nonfederal funding agencies have spent billions of dollars on clinical trials aimed at finding drugs, but we still do not have a drug or an agent that can slow the AD or PD disease process. One primary reason for this disappointing result may be that the clinical trials enroll patients with AD or PD at advances stages. Although many drugs and agents are tested preclinical and are promising, in human clinical trials, they are mostly ineffective in slowing disease progression. One therapy that has been promising is 'stem cell therapy' based on cell culture and pre-clinical studies. In the few clinical studies that have investigated therapies in clinical trials with AD and PD patients at stage I. The therapies, such as stem cell transplantation - appear to delay the symptoms in AD and PD. The purpose of this article is to describe clinical trials using 1) stem cell transplantation methods in AD and PD mouse models and 2) regenerative medicine in AD and PD mouse models, and 3) the current status of investigating preclinical stem cell transplantation in patients with AD and PD.
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Affiliation(s)
- Arubala P Reddy
- Pharmacology & Neuroscience Department, Texas Tech University Health Sciences Center, 3601 4th Street, MS 9424, Lubbock, TX 79430, United States.
| | - Janani Ravichandran
- Texas Tech University Health Sciences Center El Paso, 5001 El Paso Drive, El Paso, TX 79905, United States.
| | - Nurgul Carkaci-Salli
- Department of Pharmacology, Penn State College of Medicine, 500 University Drive, Hershey, PA 17033.
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Abstract
In the past few decades, the field of neuroepigenetics has investigated how the brain encodes information to form long-lasting memories that lead to stable changes in behaviour. Activity-dependent molecular mechanisms, including, but not limited to, histone modification, DNA methylation and nucleosome remodelling, dynamically regulate the gene expression required for memory formation. Recently, the field has begun to examine how a learning experience is integrated at the level of both chromatin structure and synaptic physiology. Here, we provide an overview of key established epigenetic mechanisms that are important for memory formation. We explore how epigenetic mechanisms give rise to stable alterations in neuronal function by modifying synaptic structure and function, and highlight studies that demonstrate how manipulating epigenetic mechanisms may push the boundaries of memory.
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Affiliation(s)
- Rianne R Campbell
- Department of Neurobiology and Behavior, Center for the Neurobiology of Learning and Memory, Center for Addiction Neuroscience, Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, CA, USA
| | - Marcelo A Wood
- Department of Neurobiology and Behavior, Center for the Neurobiology of Learning and Memory, Center for Addiction Neuroscience, Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, CA, USA.
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15
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Phan A, Thomas CI, Chakraborty M, Berry JA, Kamasawa N, Davis RL. Stromalin Constrains Memory Acquisition by Developmentally Limiting Synaptic Vesicle Pool Size. Neuron 2018; 101:103-118.e5. [PMID: 30503644 DOI: 10.1016/j.neuron.2018.11.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Revised: 08/24/2018] [Accepted: 11/01/2018] [Indexed: 12/14/2022]
Abstract
Stromalin, a cohesin complex protein, was recently identified as a novel memory suppressor gene, but its mechanism remained unknown. Here, we show that Stromalin functions as a negative regulator of synaptic vesicle (SV) pool size in Drosophila neurons. Stromalin knockdown in dopamine neurons during a critical developmental period enhances learning and increases SV pool size without altering the number of dopamine neurons, their axons, or synapses. The developmental effect of Stromalin knockdown persists into adulthood, leading to strengthened synaptic connections and enhanced olfactory memory acquisition in adult flies. Correcting the SV content in dopamine neuron axon terminals by impairing anterograde SV trafficking motor protein Unc104/KIF1A rescues the enhanced-learning phenotype in Stromalin knockdown flies. Our results identify a new mechanism for memory suppression and reveal that the size of the SV pool is controlled genetically and independent from other aspects of neuron structure and function through Stromalin.
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Affiliation(s)
- Anna Phan
- Department of Neuroscience, The Scripps Research Institute Florida, Jupiter, FL 33458, USA
| | - Connon I Thomas
- Electron Microscopy Core Facility, Max Planck Florida Institute for Neuroscience, Jupiter, FL 33458, USA
| | - Molee Chakraborty
- Department of Neuroscience, The Scripps Research Institute Florida, Jupiter, FL 33458, USA
| | - Jacob A Berry
- Department of Neuroscience, The Scripps Research Institute Florida, Jupiter, FL 33458, USA
| | - Naomi Kamasawa
- Electron Microscopy Core Facility, Max Planck Florida Institute for Neuroscience, Jupiter, FL 33458, USA
| | - Ronald L Davis
- Department of Neuroscience, The Scripps Research Institute Florida, Jupiter, FL 33458, USA.
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Smith JG, Aldous SG, Andreassi C, Cuda G, Gaspari M, Riccio A. Proteomic analysis of S-nitrosylated nuclear proteins in rat cortical neurons. Sci Signal 2018; 11:11/537/eaar3396. [PMID: 29970601 DOI: 10.1126/scisignal.aar3396] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Neurons modulate gene expression in response to extrinsic signals to enable brain development, cognition, and learning and to process stimuli that regulate systemic physiological functions. This signal-to-gene communication is facilitated by posttranslational modifications such as S-nitrosylation, the covalent attachment of a nitric oxide (NO) moiety to cysteine thiols. In the cerebral cortex, S-nitrosylation of histone deacetylase 2 (HDAC2) is required for gene transcription during neuronal development, but few other nuclear targets of S-nitrosylation have been identified to date. We used S-nitrosothiol resin-assisted capture on NO donor-treated nuclear extracts from rat cortical neurons and identified 614 S-nitrosylated nuclear proteins. Of these, 131 proteins have not previously been shown to be S-nitrosylated in any system, and 555 are previously unidentified targets of S-nitrosylation in neurons. The sites of S-nitrosylation were identified for 59% of the targets, and motifs containing single lysines were found at 33% of these sites. In addition, lysine motifs were necessary for promoting the S-nitrosylation of HDAC2 and methyl-CpG binding protein 3 (MBD3). Moreover, S-nitrosylation of the histone-binding protein RBBP7 was necessary for dendritogenesis of cortical neurons in culture. Together, our findings characterize S-nitrosylated nuclear proteins in neurons and identify S-nitrosylation motifs that may be shared with other targets of NO signaling.
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Affiliation(s)
- Jacob G Smith
- Medical Research Council Laboratory for Molecular Cell Biology, University College London, WC1E 6BT London, UK
| | - Sarah G Aldous
- Medical Research Council Laboratory for Molecular Cell Biology, University College London, WC1E 6BT London, UK
| | - Catia Andreassi
- Medical Research Council Laboratory for Molecular Cell Biology, University College London, WC1E 6BT London, UK
| | - Giovanni Cuda
- Department of Experimental and Clinical Medicine, University of Catanzaro, 88100 Catanzaro, Italy
| | - Marco Gaspari
- Department of Experimental and Clinical Medicine, University of Catanzaro, 88100 Catanzaro, Italy
| | - Antonella Riccio
- Medical Research Council Laboratory for Molecular Cell Biology, University College London, WC1E 6BT London, UK.
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