scholarly journals Loss of Aly/ALYREF Suppresses Toxicity in Both Tau and TDP-43 Models of Neurodegeneration

2021 ◽  
Author(s):  
Rebecca Kow ◽  
Aristide Black ◽  
Aleen Saxton ◽  
Nicole Liachko ◽  
Brian Kraemer
Keyword(s):  
Nuclear Export ◽  
Molecular Mechanisms ◽  
Rna Binding ◽  
Mrna Levels ◽  
Tau Pathology ◽  
Human Cell Culture ◽  
Behavioral Deficits ◽  
C Elegans ◽  
Protein Levels ◽  
Binding Protein Gene

Abstract Background Neurodegenerative diseases with tau pathology, or tauopathies, include Alzheimer’s Disease and related dementia disorders. Previous work has shown that loss of the poly(A) RNA-binding protein gene sut2/MSUT2 strongly suppressed tauopathy in C. elegans, human cell culture, and mouse models of tauopathy. However, the mechanism of suppression is still unclear. Recent work has shown that MSUT2 protein interacts with the THO complex and ALYREF, which are components of the mRNA nuclear export complex. Additionally, previous work showed ALYREF homolog Ref1 modulates TDP-43 and G 4 C 2 toxicity in D. melanogaster models. Methods We used transgenic C. elegans models of tau or TDP-43 toxicity to investigate the effects of loss of ALYREF function on tau and TDP-43 toxicity. In C. elegans, there are three genes that are homologous to human ALYREF: aly-1, aly-2, and aly-3. Results We found that loss of C. elegans aly gene function, especially loss of both aly-2 and aly-3, suppressed tau-induced toxic phenotypes. Loss of aly-2 and aly-3 was also able to suppress TDP-43-induced behavioral deficits. However, loss of aly-2 and aly-3 had divergent effects on mRNA and protein levels as total tau protein levels were reduced while mRNA levels were increased, but no significant effects were seen on total TDP-43 protein or mRNA levels. Conclusions Our results suggest that although aly genes modulate both tau and TDP-43-induced toxicity phenotypes, the molecular mechanisms of suppression are different and separated from impacts on mRNA and protein levels. Altogether this study highlights the importance of elucidating RNA-related mechanisms in both tau and TDP-43-induced toxicity.

scholarly journals RBFOX3 regulates Claudin-1 expression in human lung tissue via attenuation of proteasomal degradation

2017 ◽  
Vol 37 (1) ◽  
Author(s):  
Yong-Eun Kim ◽  
Sunkyung Choi ◽  
Jong Ok Kim ◽  
Kee K. Kim
Keyword(s):  
Lung Tissue ◽  
Molecular Mechanisms ◽  
Neuronal Development ◽  
Rna Binding ◽  
Human Lung ◽  
Human Lung Cancer ◽  
Mrna Levels ◽  
Human Lung Tissue ◽  
Protein Levels ◽  
The Stability

RBFOX3, a nuclear RNA-binding protein, is well known as a regulator of alternative pre-mRNA splicing during neuronal development. However, other functions of RBFOX3 are poorly understood. Here, we investigated the function of RBFOX3 in the cytoplasm with respect to regulation of Claudin-1 expression. In human lung tissue, Claudin-1 is higher in RBFOX3-positive cells than in RBFOX3-negative cells. Immunostaining and mRNA quantification revealed that protein levels, but not mRNA levels, of Claudin-1 are increased by RBFOX3. In addition, cycloheximide treatment of human lung cancer cells revealed that RBFOX3 increases the stability of Claudin-1 through attenuation of its ubiquitination. Our study provides insights into the molecular mechanisms by which RBFOX3 regulates Claudin-1 expression in human lung tissue.

scholarly journals Eukaryotic initiation factor EIF-3.G augments mRNA translation efficiency to regulate neuronal activity

2021 ◽  
Author(s):  
Stephen M Blazie ◽  
Seika Takayanagi-Kiya ◽  
Katherine A McCulloch ◽  
Yishi Jin
Keyword(s):  
Rna Binding ◽  
Mrna Translation ◽  
Initiation Factor ◽  
Translation Efficiency ◽  
Dependent Manner ◽  
Control Activity ◽  
C Elegans ◽  
Protein Levels ◽  
Neuronal Protein

AbstractThe translation initiation complex eIF3 imparts specialized functions to regulate protein expression. However, understanding of eIF3 activities in neurons remains limited despite widespread dysregulation of eIF3 subunits in neurological disorders. Here, we report a selective role of theC. elegansRNA-binding subunit EIF-3.G in shaping the neuronal protein landscape. We identify a missense mutation in the conserved Zinc-Finger (ZF) of EIF-3.G that acts in a gain-of-function manner to dampen neuronal hyperexcitation. Using neuron type-specific seCLIP, we systematically mapped EIF-3.G-mRNA interactions and identified EIF-3.G occupancy on GC-rich 5′UTRs of a select set of mRNAs enriched in activity-dependent functions. We demonstrate that the ZF mutation in EIF-3.G alters translation in a 5′UTR dependent manner. Our study reveals anin vivomechanism for eIF3 in governing neuronal protein levels to control activity states and offers insights into how eIF3 dysregulation contributes to neuronal disorders.

scholarly journals Escin Increases the Survival Rate of LPS-Induced Septic Mice Through Inhibition of HMGB1 Release from Macrophages

2015 ◽  
Vol 36 (4) ◽  
pp. 1577-1586 ◽  
Author(s):  
Yajun Cheng ◽  
Hongrui Wang ◽  
Min Mao ◽  
Chao Liang ◽  
Yu Zhang ◽  
...  
Keyword(s):  
Survival Rate ◽  
Western Blot ◽  
Inflammatory Cytokines ◽  
Molecular Mechanisms ◽  
Post Treatment ◽  
Mrna Levels ◽  
Treatment Methods ◽  
Protein Levels ◽  
Qrt Pcr ◽  
Pro Inflammatory Cytokines

Background: Previous studies have described the effects of Escin on improving the survival rate of endotoxemic animals. The purpose of this study was to explore the molecular mechanisms of this potentially beneficial treatment. Methods: First, the survival rate of endotoxemic mice was monitored for up to 2 weeks after Escin pretreatment, Escin post-treatment, or Escin post-treatment + rHMGB1. The effects of Escin on the release of pro-inflammatory cytokines such as TNF-a, IL-1ß, IL-6 and HMGB1 in the serum of endotoxemic mice and LPS-induced macrophages were evaluated by ELISA. Furthermore, the mRNA and protein levels of HMGB1 in LPS-induced macrophages were measured by qRT-PCR and Western blot, respectively. Additionally, the release of pro-inflammatory cytokines such as TNF-a, IL-1ß, IL-6 was evaluated by ELISA in rHMGB1-induced macrophages. Finally, the protein levels and the activity of NF-κB in macrophages were checked by Western blot and ELISA, respectively. Results: Both pretreatment and post-treatment with Escin could improve the survival rate of endotoxemic mice, while exogenous rHMGB1 reversed this effect. In addition, Escin decreased the level of the pro-inflammatory cytokines TNF-a, IL-1ß, IL-6 and HMGB1 in endotoxemic mice and in LPS-induced macrophages. Escin could also inhibit the mRNA levels and activity of HMGB1. The release of the pro-inflammatory cytokines TNF-a, IL-1ß, IL-6 could be suppressed in rHMGB1-induced macrophages by Escin. Finally, Escin could suppress the activation of NF-κB in LPS-induced macrophages. Conclusion: Escin could improve the survival of mice with LPS-induced endotoxemia. This effect maybe meditated by reducing the release of HMGB1, resulting in the suppression of the release of pro-inflammatory cytokines.

scholarly journals Trypanosoma brucei RNA Binding Proteins p34 and p37 Mediate NOPP44/46 Cellular Localization via the Exportin 1 Nuclear Export Pathway

2007 ◽  
Vol 6 (12) ◽  
pp. 2206-2213 ◽  
Author(s):  
Kristina Hellman ◽  
Kimberly Prohaska ◽  
Noreen Williams
Keyword(s):  
Amino Acid ◽  
Trypanosoma Brucei ◽  
Nuclear Export ◽  
Cellular Localization ◽  
Binding Proteins ◽  
Rna Binding ◽  
Rna Binding Proteins ◽  
Nuclear Export Signal ◽  
Amino Acid Sequences ◽  
Protein Levels

ABSTRACT We have previously identified and characterized two novel nuclear RNA binding proteins, p34 and p37, which have been shown to interact with a family of nucleolar phosphoproteins, NOPP44/46, in Trypanosoma brucei. These proteins are nearly identical, the major difference being an 18-amino-acid insert in the N terminus of p37. In order to characterize the interaction between p34 and p37 and NOPP44/46, we have utilized an RNA interference (RNAi) cell line that specifically targets p34 and p37. Within these RNAi cells, we detected a disruption of a higher-molecular-weight complex containing NOPP44/46, as well as a dramatic increase in nuclear NOPP44/46 protein levels. We demonstrated that no change occurred in NOPP44/46 mRNA steady-state levels or stability, nor was there a change in cellular protein levels. These results led us to investigate whether p34 and p37 regulate NOPP44/46 cellular localization. Examination of the p34 and p37 amino acid sequences revealed a leucine-rich nuclear export signal, which interacts with the nuclear export factor exportin 1. Immune capture experiments demonstrated that p34, p37, and NOPP44/46 associate with exportin 1. When these experiments were performed with p34/p37 RNAi cells, NOPP44/46 no longer associated with exportin 1. Sequential immune capture experiments demonstrated that p34, p37, NOPP44/46, and exportin 1 exist in a common complex. Inhibiting exportin 1-mediated nuclear export led to an increase in nuclear NOPP44/46 proteins, indicating that they are exported from the nucleus via this pathway. Together, our results demonstrate that p34 and p37 regulate NOPP44/46 cellular localization by facilitating their association with exportin 1.

scholarly journals The RNA-binding protein HuR regulates intestinal epithelial restitution by modulating Caveolin-1 gene expression

2020 ◽  
Author(s):  
Shan Cao ◽  
Lan Xiao ◽  
Junyao Wang ◽  
Guodong Chen ◽  
Yulan Liu
Keyword(s):  
Gene Expression ◽  
Posttranscriptional Regulation ◽  
Rna Binding ◽  
Rna Binding Protein ◽  
Mrna Levels ◽  
Epithelial Repair ◽  
Caveolin 1 ◽  
Protein Levels ◽  
Ectopic Overexpression

The integrity of the intestinal mucosal barrier protects hosts against pathological conditions. Early mucosal restitution after wounding refers to epithelial cell migration into a defect. The RNA-binding protein HuR plays an important role in the posttranscriptional regulation of gene expression and is involved in many aspects of cellular physiology. In the present study, we investigated the role of HuR in the regulation of cell migration through the posttranscriptional regulation of Caveolin-1 (Cav-1). Online software was used to identify Cav-1 mRNA as a potential target of HuR. The interaction of HuR with Cav-1 mRNA was investigated via ribonucleoprotein immunoprecipitation (RNP IP) assays and biotin pulldown analysis. HuR was found to bind specifically to the Cav-1 3’-UTR rather than the coding region or 5’-UTR. Transfection of cells with siHuR decreased both HuR protein levels and Cav-1 protein levels; conversely, ectopic overexpression of HuR via infection of cells with an adenoviral vector containing HuR cDNA (AdHuR) increased Cav-1 protein levels without disturbing Cav-1 mRNA levels. Thus, HuR enhanced Cav-1 expression in vitro by stimulating Cav-1 translation. Intestinal epithelium–specific HuR knockout in mice decreased Cav-1 protein levels without changing Cav-1 mRNA levels, consistent with the in vitro results. Decreasing the levels of HuR via siHuR transfection inhibited early epithelial repair, but this effect was reversed by ectopic overexpression of GFP-tagged Cav-1. These results indicate that posttranscriptional regulation of Cav-1 gene expression by HuR plays a critical role in the regulation of rapid epithelial repair after wounding.

scholarly journals BMP6 Mediates BMP2-Increased Human Trophoblast Invasion

2021 ◽  
Vol 5 (Supplement_1) ◽  
pp. A747-A747
Author(s):  
Jianye Deng ◽  
Yan Li
Keyword(s):  
Molecular Mechanisms ◽  
First Trimester ◽  
Bone Morphogenetic Protein 2 ◽  
Extravillous Trophoblast ◽  
Trophoblast Invasion ◽  
Mrna Levels ◽  
Ongoing Research ◽  
Human Trophoblast ◽  
Protein Levels ◽  
Regulatory Effects

Abstract TGF-β superfamily proteins play divergent roles in regulating human extravillous trophoblast (EVT) invasion and their coordinated effects are essential for adequate placentation during pregnancy 1. Bone morphogenetic protein 2 (BMP2), which belongs to the BMP subfamily of TGF-β superfamily, has been shown to promote human EVT invasion and the acquisition of endothelial-like phenotype 2,3. It has been reported that BMP2 promotes EVT invasion by up-regulating Activin A, a growth factor which also belongs to TGF-β superfamily. However, whether BMP6 mediates the pro-invasive effect of BMP2 has yet to be determined. Herein, we firstly treated immortalized trophoblast cells (HTR8/SVneo) with recombinant BMP2 protein for 6 and 24 hrs, and our bulk-RNA sequencing results demonstrated significantly increased BMP6 mRNA levels after BMP2 treatment. Furthermore, we confirmed the up-regulatory effects of BMP2 on BMP6 mRNA and protein levels in both HTR8/SVneo and primary EVTs isolated from first-trimester villi. Notably, siRNA-mediated down-regulation of BMP6 significantly attenuated both basal and BMP2-induced cell invasion in HTR8/SVneo cells as measured by Matrigel-coated transwell invasion assay. In summary, our results firstly demonstrated the up-regulatory effect of BMP2 on BMP6 expression in human trophoblasts and identified the mediation role of BMP6 in BMP2-promoted EVT invasion, suggesting the interplay between BMP subfamily members during EVT invasion regulation. Our ongoing research focusing the underlying molecular mechanisms and signaling pathways could further benefit the advancement of diagnostic and therapeutic strategies for EVT invasion dysregulation-related pregnancy disorders, e.g., pre-eclampsia. Reference: (1) Li Yan et al., Trends Endocrinol Metab 2021 18: S1043-2760(20)30266-6. (2) Hong-Jin Zhao et al., FASEB J 2020;34(2):3151-3164. (3) Hong-Jin Zhao et al., Cell Death Dis 2018;9(2):174.

Multiple Roles of RNA Regulatory Factors in Neuronal Development and Function in C. elegans

2020 ◽  
Author(s):  
Matthew G. Andrusiak ◽  
Yishi Jin
Keyword(s):  
Nervous System ◽  
Cell Biology ◽  
Molecular Mechanisms ◽  
Neuronal Development ◽  
Rna Binding ◽  
Rna Binding Proteins ◽  
Model Organism ◽  
Nervous System Development ◽  
Forward Genetics ◽  
C Elegans

Recent evidence has highlighted the dynamic nature of mRNA regulation, particularly in the nervous system, from complex pre-mRNA processing to long-range transport and long-term storage of mature mRNAs. In accordance with the importance for mRNA-mediated regulation of nervous system development and maintenance, various mutations in RNA-binding proteins are associated with a range of human disorders. C. elegans express many RNA-binding factors that have human orthologs and perform similar biochemical functions. This chapter focuses on the research using C. elegans to dissect molecular mechanisms involving mRNA-mediated pathways. It highlights the key approaches and findings that integrate genetic and genomic studies in the nervous system. The analyses of genetic mutants, primarily using forward genetics, offer functional insights for genes important for neuronal development, synaptic transmission, and neuronal repair. In combination with single-neuron cell biology and cell-type genomics, the knowledge learned from this model organism has continued to lead to ground-breaking discoveries.

scholarly journals Changes in Serum Iron and Leukocyte mRNA Levels of Genes Involved in Iron Metabolism in Amateur Marathon Runners—Effect of the Running Pace

Genes ◽  
2019 ◽  
Vol 10 (6) ◽  
pp. 460 ◽  
Author(s):  
Agata Grzybkowska ◽  
Katarzyna Anczykowska ◽  
Wojciech Ratkowski ◽  
Piotr Aschenbrenner ◽  
Jędrzej Antosiewicz ◽  
...  
Keyword(s):  
Gene Expression ◽  
Iron Metabolism ◽  
Serum Iron ◽  
Molecular Mechanisms ◽  
Mrna Levels ◽  
Marathon Runners ◽  
Time Points ◽  
Protein Levels ◽  
Reactive Protein ◽  
Blood Morphology

Iron is essential for physical activity due to its role in energy production pathways and oxygen transportation via hemoglobin and myoglobin. Changes in iron-related biochemical parameters after physical exercise in athletes are of substantial research interest, but molecular mechanisms such as gene expression are still rarely tested in sports. In this paper, we evaluated the mRNA levels of genes related to iron metabolism (PCBP1, PCBP2, FTL, FTH, and TFRC) in leukocytes of 24 amateur runners at four time points: before, immediately after, 3 h after, and 24 h after a marathon. We measured blood morphology as well as serum concentrations of iron, ferritin, and C-reactive protein (CRP). Our results showed significant changes in gene expression (except for TFRC), serum iron, CRP, and morphology after the marathon. However, the alterations in mRNA and protein levels occurred at different time points (immediately and 3 h post-run, respectively). The levels of circulating ferritin remained stable, whereas the number of transcripts in leukocytes differed significantly. We also showed that running pace might influence mRNA expression. Our results indicated that changes in the mRNA of genes involved in iron metabolism occurred independently of serum iron and ferritin concentrations.

The RNA-binding protein Quaking regulates multiciliated and basal cell abundance in the developing lung

2021 ◽  
Author(s):  
Dustin Ameis ◽  
Franklin Liu ◽  
Eimear Kirby ◽  
Daywin Patel ◽  
Richard Keijzer
Keyword(s):  
Basal Cell ◽  
Lung Development ◽  
Rna Binding ◽  
Rna Binding Proteins ◽  
Branching Morphogenesis ◽  
Lung Cells ◽  
Mrna Levels ◽  
Basal Cells ◽  
Protein Levels ◽  
Multiciliated Cells

RNA-binding proteins (RBPs) form complexes with RNA, changing how the RNA is processed and thereby regulating gene expression. RBPs are important sources of gene regulation during organogenesis, including the development of the lungs. The RBP called Quaking (QK) is critical for embryogenesis, yet has not been studied in the developing lung. Here, we show that QK is widely expressed during rat lung development and into adulthood. The QK isoforms QK5 and QK7 co-localize to the nuclei of nearly all lung cells. QK6 is present in the nuclei and cytoplasm of mesenchymal cells and is only present in the epithelium during branching morphogenesis. QK knockdown in embryonic lung explants caused a greater number of multiciliated cells to appear in the airways, at the expense of basal cells. The mRNA of multiciliated cell genes and the abundance of FOXJ1/SOX2+ cells increased after knockdown, while P63/SOX2+ cells decreased. The cytokine IL-6, a known regulator of multiciliated cell differentiation, had increased mRNA levels after QK knockdown, although protein levels remained unchanged. Further studies are necessary to confirm whether QK acts as a blocker for the IL-6 induced differentiation of basal cell into multiciliated cells, and a conditional QK knockout would likely lead to additional discoveries on QK's role during lung development.

scholarly journals Activation of alternative NF-κB signaling during recovery of disuse-induced loss of muscle oxidative phenotype

2014 ◽  
Vol 306 (6) ◽  
pp. E615-E626 ◽  
Author(s):  
A. H. V. Remels ◽  
N. A. Pansters ◽  
H. R. Gosker ◽  
A. M. W. J. Schols ◽  
R. C. J. Langen
Keyword(s):  
Molecular Mechanisms ◽  
Myosin Heavy Chain Isoforms ◽  
Sirtuin 1 ◽  
Hindlimb Suspension ◽  
Peroxisome Proliferator ◽  
Mrna Levels ◽  
Peroxisome Proliferator Activated Receptor ◽  
Expression Levels ◽  
Protein Levels ◽  
Oxidative Phenotype

Physical inactivity-induced loss of skeletal muscle oxidative phenotype (OXPHEN), often observed in chronic disease, adversely affects physical functioning and quality of life. Potential therapeutic targets remain to be identified, since the molecular mechanisms involved in reloading-induced recovery of muscle OXPHEN remain incompletely understood. We hypothesized a role for alternative NF-κB, as a recently identified positive regulator of muscle OXPHEN, in reloading-induced alterations in muscle OXPHEN. Markers and regulators (including alternative NF-κB signaling) of muscle OXPHEN were investigated in gastrocnemius muscle of mice subjected to a hindlimb suspension/reloading (HLS/RL) protocol. Expression levels of oxidative phosphorylation subunits and slow myosin heavy chain isoforms I and IIA increased rapidly upon RL. After an initial decrease upon HLS, mRNA levels of peroxisome proliferator-activated receptor (PPAR)-γ coactivator (PGC) molecules PGC-1α and PGC-1β and mRNA levels of mitochondrial transcription factor A (Tfam) and estrogen-related receptor α increased upon RL. PPAR-δ, nuclear respiratory factor 1 (NRF-1), NRF-2α, and sirtuin 1 mRNA levels increased during RL although expression levels were unaltered upon HLS. In addition, both Tfam and NRF-1 protein levels increased significantly during the RL period. Moreover, upon RL, IKK-α mRNA and protein levels increased, and phosphorylation of P100 and subsequent processing to P52 were elevated, reflecting alternative NF-κB activation. We conclude that RL-induced recovery of muscle OXPHEN is associated with activation of alternative NF-κB signaling.

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