Dyrk1A Influences Neuronal Morphogenesis Through Regulation of Cytoskeletal Dynamics in Mammalian Cortical Neurons

Neurite elongation and branching in developing neurons requires plasmalemma expansion, hypothesized to occur primarily via exocytosis. We posited that exocytosis in developing neurons and nonneuronal cells would exhibit distinct spatiotemporal organization. We exploited total internal reflection fluorescence microscopy to image vesicle-associated membrane protein (VAMP)–pHluorin—mediated exocytosis in mouse embryonic cortical neurons and interphase melanoma cells, and developed computer-vision software and statistical tools to uncover spatiotemporal aspects of exocytosis. Vesicle fusion behavior differed between vesicle types, cell types, developmental stages, and extracellular environments. Experiment-based mathematical calculations indicated that VAMP2-mediated vesicle fusion supplied excess material for the plasma membrane expansion that occurred early in neuronal morphogenesis, which was balanced by clathrin-mediated endocytosis. Spatial statistics uncovered distinct spatiotemporal regulation of exocytosis in the soma and neurites of developing neurons that was modulated by developmental stage, exposure to the guidance cue netrin-1, and the brain-enriched ubiquitin ligase tripartite motif 9. In melanoma cells, exocytosis occurred less frequently, with distinct spatial clustering patterns.

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Effects of 5-HT receptor on cytoskeletal dynamics in the dendrite formation of cortical neurons

Neuroscience Research ◽

10.1016/j.neures.2011.07.1461 ◽

2011 ◽

Vol 71 ◽

pp. e334

Author(s):

Akiko Ohtani ◽

Fei Li ◽

Kouji Senzaki ◽

Takashi Shiga

Keyword(s):

Cortical Neurons ◽

Dendrite Formation ◽

Cytoskeletal Dynamics

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SCYL1BP1 modulates neurite outgrowth and regeneration by regulating the Mdm2/p53 pathway

Molecular Biology of the Cell ◽

10.1091/mbc.e12-05-0362 ◽

2012 ◽

Vol 23 (23) ◽

pp. 4506-4514 ◽

Cited By ~ 32

Author(s):

Yonghua Liu ◽

Ying Chen ◽

Xiang Lu ◽

Youhua Wang ◽

Yinong Duan ◽

...

Keyword(s):

Neurite Outgrowth ◽

Cortical Neurons ◽

Axonal Regeneration ◽

P53 Protein ◽

Transcriptional Activator ◽

Small Interfering Rnas ◽

P53 Pathway ◽

Neuronal Morphogenesis

SCY1-like 1–binding protein 1 (SCYL1BP1) is a newly identified transcriptional activator domain containing a protein with many unknown biological functions. Recently emerging evidence has revealed that it is a novel regulator of the p53 pathway, which is required for neurite outgrowth and regeneration. Here we present evidence that SCYL1BP1 inhibits nerve growth factor–mediated neurite outgrowth in PC12 cells and affects morphogenesis of primary cortical neurons by strongly decreasing the p53 protein level in vitro, all of which depends on SCYL1BP1's transcriptional activator domain. Exogenous p53 rescues neurite outgrowth and neuronal morphogenesis defects caused by SCYL1BP1. Furthermore, SCYL1BP1 can directly induce Mdm2 transcription, whereas inhibiting the function of Mdm2 by specific small interfering RNAs results in partial rescue of neurite outgrowth and neuronal morphogenesis defects induced by SCYL1BP1. In vivo experiments show that SCYL1BP1 can also depress axonal regeneration, whereas inhibiting the function of SCYL1BP1 by specific short hairpin RNA enhances it. Taken together, these data strongly suggested that SCYL1BP1 is a novel transcriptional activator in neurite outgrowth by directly modulating the Mdm2/p53-dependent pathway, which might play an important role in CNS development and axonal regeneration after injury.

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Nestin in immature embryonic neurons regulates axon growth cone morphology and Semaphorin3a sensitivity

10.1101/228296 ◽

2017 ◽

Author(s):

C.J. Bott ◽

C. G. Johnson ◽

C.C. Yap ◽

N.D. Dwyer ◽

K.A. Litwa ◽

...

Keyword(s):

Growth Cone ◽

Intermediate Filament ◽

Cortical Neurons ◽

Axon Growth ◽

Neural Progenitors ◽

Nestin Expression ◽

Guidance Cue ◽

Cytoskeletal Dynamics ◽

Newborn Neurons

AbstractCorrect wiring in the neocortex requires that responses to an individual guidance cue vary among neurons in the same location, and within the same neuron over time. Nestin is an atypical intermediate filament expressed highly in neural progenitors and is thus used widely as a progenitor marker. Here we show a subpopulation of embryonic cortical neurons which transiently express nestin in their axons. Nestin expression is thus not restricted to neural progenitors but persists at lower levels in some newborn neurons for 2-3 days. We found that nestin-expressing neurons have smaller growth cones, suggesting that nestin affects cytoskeletal dynamics. Nestin, unlike other intermediate filament subtypes, regulates cdk5 kinase. Cdk5 activity is induced by the repulsive guidance cue Sema3a leading to growth cone collapse in vitro. Therefore, we tested whether nestin-expressing neurons showed altered responses to Sema3a. We find that nestin-expressing newborn neurons are more sensitive to Sema3a in a roscovitine-sensitive manner, whereas nestin knockdown results in lowered sensitivity to Sema3a. We propose that nestin functions in immature neurons to modulate cdk5 and thereby the Sema3a response. Thus, the transient expression of nestin could allow for temporal modulation of a neuron's response to Sema3a particularly during early axon guidance decisions.

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Recent advances in branching mechanisms underlying neuronal morphogenesis

F1000Research ◽

10.12688/f1000research.16038.1 ◽

2018 ◽

Vol 7 ◽

pp. 1779 ◽

Cited By ~ 15

Author(s):

Shalini Menon ◽

Stephanie Gupton

Keyword(s):

Intracellular Signaling ◽

Synapse Formation ◽

Neuronal Morphogenesis ◽

Effector Cells ◽

Signaling Mechanisms ◽

Recent Advances ◽

Dendritic Branching ◽

Branch Formation ◽

Cytoskeletal Dynamics ◽

To Receive

Proper neuronal wiring is central to all bodily functions, sensory perception, cognition, memory, and learning. Establishment of a functional neuronal circuit is a highly regulated and dynamic process involving axonal and dendritic branching and navigation toward appropriate targets and connection partners. This intricate circuitry includes axo-dendritic synapse formation, synaptic connections formed with effector cells, and extensive dendritic arborization that function to receive and transmit mechanical and chemical sensory inputs. Such complexity is primarily achieved by extensive axonal and dendritic branch formation and pruning. Fundamental to neuronal branching are cytoskeletal dynamics and plasma membrane expansion, both of which are regulated via numerous extracellular and intracellular signaling mechanisms and molecules. This review focuses on recent advances in understanding the biology of neuronal branching.

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The drebrin/EB3 pathway regulates cytoskeletal dynamics to drive neuritogenesis in embryonic cortical neurons

Journal of Neurochemistry ◽

10.1111/jnc.15502 ◽

2021 ◽

Author(s):

Thanushiyan Poobalasingam ◽

Francesca Bianco ◽

Fazal Oozeer ◽

Phillip R. Gordon‐Weeks

Keyword(s):

Cortical Neurons ◽

Cytoskeletal Dynamics

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Modulation of Gene Expression and Cytoskeletal Dynamics by the Amyloid Precursor Protein Intracellular Domain (AICD)

Molecular Biology of the Cell ◽

10.1091/mbc.e06-04-0283 ◽

2007 ◽

Vol 18 (1) ◽

pp. 201-210 ◽

Cited By ~ 81

Author(s):

Thorsten Müller ◽

Caoimhin G. Concannon ◽

Manus W. Ward ◽

Ciara M. Walsh ◽

Anca L. Tirniceriu ◽

...

Keyword(s):

Gene Regulation ◽

Amyloid Precursor Protein ◽

Actin Cytoskeleton ◽

Cortical Neurons ◽

Target Genes ◽

Physiological Role ◽

Precursor Protein ◽

Intracellular Domain ◽

Cytoskeletal Dynamics

Amyloidogenic processing of the amyloid precursor protein (APP) results in the generation of β-amyloid, the main constituent of Alzheimer plaques, and the APP intracellular domain (AICD). Recently, it has been demonstrated that AICD has transactivation potential; however, the targets of AICD-dependent gene regulation and hence the physiological role of AICD remain largely unknown. We analyzed transcriptome changes during AICD-dependent gene regulation by using a human neural cell culture system inducible for expression of AICD, its coactivator FE65, or the combination of both. Induction of AICD was associated with increased expression of genes with known function in the organization and dynamics of the actin cytoskeleton, including α2-Actin and Transgelin (SM22). AICD target genes were also found to be differentially regulated in the frontal cortex of Alzheimer's disease patients compared with controls as well as in AICD/FE65 transiently transfected murine cortical neurons. Confocal image analysis of neural cells and cortical neurons expressing both AICD and FE65 confirmed pronounced changes in the organization of the actin cytoskeleton, including the destabilization of actin fibers and clumping of actin at the sites of cellular outgrowth. Our data point to a role of AICD in developmental and injury-related cytoskeletal dynamics in the nervous system.

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The C. elegans homolog of human panic-disorder risk gene TMEM132D orchestrates neuronal morphogenesis through the WAVE-regulatory complex

Molecular Brain ◽

10.1186/s13041-021-00767-w ◽

2021 ◽

Vol 14 (1) ◽

Author(s):

Xin Wang ◽

Wei Jiang ◽

Shuo Luo ◽

Xiaoyu Yang ◽

Changnan Wang ◽

...

Keyword(s):

Mammalian Cells ◽

Depressive Disorders ◽

Loss Of Function ◽

Neuronal Morphogenesis ◽

C Elegans ◽

Panic Disorders ◽

Risk Alleles ◽

Cytoskeletal Dynamics ◽

Regulatory Complex ◽

Major Depressive Disorders

AbstractTMEM132D is a human gene identified with multiple risk alleles for panic disorders, anxiety and major depressive disorders. Defining a conserved family of transmembrane proteins, TMEM132D and its homologs are still of unknown molecular functions. By generating loss-of-function mutants of the sole TMEM132 ortholog in C. elegans, we identify abnormal morphologic phenotypes in the dopaminergic PDE neurons. Using a yeast two-hybrid screen, we find that NAP1 directly interacts with the cytoplasmic domain of human TMEM132D, and mutations in C. elegans tmem-132 that disrupt interaction with NAP1 cause similar morphologic defects in the PDE neurons. NAP1 is a component of the WAVE regulatory complex (WRC) that controls F-actin cytoskeletal dynamics. Decreasing activity of WRC rescues the PDE defects in tmem-132 mutants, whereas gain-of-function of TMEM132D in mammalian cells inhibits WRC, leading to decreased abundance of select WRC components, impaired actin nucleation and cell motility. We propose that metazoan TMEM132 family proteins play evolutionarily conserved roles in regulating NAP1 protein homologs to restrict inappropriate WRC activity, cytoskeletal and morphologic changes in the cell.

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TRIM67 Regulates Exocytic Mode and Neuronal Morphogenesis via SNAP47

10.1101/2020.02.01.930404 ◽

2020 ◽

Cited By ~ 2

Author(s):

Fabio L. Urbina ◽

Shalini Menon ◽

Dennis Goldfarb ◽

Reginald Edwards ◽

M. Ben Major ◽

...

Keyword(s):

Plasma Membrane ◽

Ubiquitin Ligase ◽

Cortical Neurons ◽

Fusion Pore ◽

Membrane Material ◽

New Classification ◽

Vesicle Membrane ◽

Neuronal Morphogenesis ◽

Neuronal Synapses ◽

Developing Neurons

AbstractNeuronal morphogenesis involves dramatic plasma membrane expansion, likely fueled by SNARE-mediated exocytosis. Distinct fusion modes described at neuronal synapses include full-vesicle-fusion (FVF) and kiss-and-run fusion (KNR). During FVF, lumenal cargo is secreted and vesicle membrane incorporates into the plasma membrane. During KNR a transient fusion pore secretes cargo, but closes without membrane addition. In contrast, fusion modes are not described in developing neurons where plasma membrane expansion is significant. Here, we resolve individual exocytic events in developing murine cortical neurons and use new classification tools to identify four distinguishable fusion modes: two FVF-like modes that insert membrane material and two KNR-like modes that do not. Discrete fluorescence profiles suggest distinct behavior of the fusion pore with each mode. Simulations and experiments agree that FVF-like exocytosis provides sufficient membrane material for morphogenesis. We find the E3 ubiquitin ligase TRIM67 promotes FVF-like exocytosis. Our data suggest this is accomplished in part by limiting incorporation of the Qb/Qc SNARE SNAP47 into SNARE complexes and thus, SNAP47 involvement in exocytosis.

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The C. elegans homolog of TMEM132D, a human panic-disorder and anxiety risk gene, modulates neuronal morphogenesis through the WAVE-regulatory complex

10.1101/2020.11.16.385906 ◽

2020 ◽

Author(s):

Xin Wang ◽

Wei Jiang ◽

Shuo Luo ◽

Xiaoyu Yang ◽

Changnan Wang ◽

...

Keyword(s):

Mammalian Cells ◽

Depressive Disorders ◽

Loss Of Function ◽

Neuronal Morphogenesis ◽

C Elegans ◽

Panic Disorders ◽

Risk Alleles ◽

Cytoskeletal Dynamics ◽

Regulatory Complex ◽

Major Depressive Disorders

SUMMARYTMEM132D is a human gene identified with multiple risk alleles for panic disorders, anxiety and major depressive disorders. Belonging to a conserved family of transmembrane proteins, TMEM132D and its homologs are still of unknown molecular functions. By generating loss-of-function mutants of the sole TMEM132 ortholog in C. elegans, we identify abnormal morphologic phenotypes in the dopaminergic PDE neurons. Using a yeast two-hybrid screen, we find that NAP1 directly interacts with the cytoplasmic domain of human TMEM132D, and mutations in C. elegans tmem-132 that disrupt the interaction with NAP1 cause similar morphologic defects in the PDE neurons. NAP1 is a component of the WAVE regulatory complex (WRC) that controls F-actin cytoskeletal dynamics. Decreasing activity of WRC rescues the PDE defects in tmem-132 mutants, whereas gain-of-function of TMEM132D in mammalian cells inhibits WRC, leading to decreased abundance of selective WRC components, impaired actin nucleation and cell motility. We propose that metazoan TMEM132 family proteins play evolutionarily conserved roles in regulating NAP1 protein homologs to restrict inappropriate WRC activity, cytoskeletal and morphologic changes in the cell.

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