scholarly journals miR-101-3p Contributes to α-Synuclein Aggregation in Neural Cells through the miR-101-3p/SKP1/PLK2 Pathway

2021 ◽  
Vol 2021 ◽  
pp. 1-8
Author(s):  
Min Zhang ◽  
Wei Liu ◽  
Qingan Zhang ◽  
Hongfeng Hu
Keyword(s):  
Substantia Nigra ◽  
Target Gene ◽  
Luciferase Activity ◽  
Substantia Nigra Pars Compacta ◽  
Activity Assay ◽  
Protein Ubiquitination ◽  
Ubiquitination Assay ◽  
Luciferase Activity Assay ◽  
Vitro Protein

Parkinson’s disease (PD) is a neurodegenerative disorder characterized by progressive neuronal loss in different brain regions, including the dopaminergic (DA) neurons of the substantia nigra pars compacta (SNc). The aggregation of α-synuclein (α-Syn) plays an essential role in the progression of PD-related neuron toxicity. In this study, bioinformatic analysis was used to confirm differentially expressed genes between patients with PD and healthy donors. Immunofluorescence was used to study the aggregation of α-Syn. Flow cytometry was used to confirm the apoptosis of neurons. Western blot was used to investigate the underlying mechanism. Coimmunoprecipitation (co-IP) was used to verify the interaction between proteins. Luciferase activity assay was used to confirm the target gene of miRNA. In vitro protein ubiquitination assay was used to ascertain the role of S-phase kinase-associated protein 1 (SKP1) on the ubiquitination processes of polo-like kinase 2 (PLK2). The result indicated that miR-101-3p was overexpressed in the substantia nigra of the postmortem brains of patients with PD. The underlying role was investigated in the SH-SY5Y cell line. The overexpression of α-Syn did not result in toxicity or aggregation. However, the co-overexpression of miR-101-3p and α-Syn promoted aggregation and neuron toxicity. Luciferase activity assay indicated that SKP1 is a target gene of miR-101-3p. The co-IP experiment confirmed that SKP1 could directly interact with PLK2. In vitro protein ubiquitination assay confirmed that SKP1 could promote the ubiquitination and subsequent protein degradation of PLK2. We also observed that the cotransfection of short hairpin RNA that targets PLK2 and α-Syn overexpression plasmid results in the endoplasmic reticulum stress of neurons. Our results collectively provide evidence that miR-101-3p contributes to α-Syn aggregation in neurons through the miR-101-3p/SKP1/PLK2 pathway.

Variants in miRNA regulome and their association with the risk of nonsyndromic orofacial clefts

Epigenomics ◽  
2020 ◽  
Vol 12 (13) ◽  
pp. 1109-1121
Author(s):  
Guirong Zhu ◽  
Chi Zhang ◽  
Yuting Wang ◽  
Yuli Wang ◽  
Dandan Li ◽  
...  
Keyword(s):  
Cell Apoptosis ◽  
Cleft Lip ◽  
Target Gene ◽  
Luciferase Activity ◽  
Nucleotide Polymorphisms ◽  
Activity Assay ◽  
Orofacial Clefts ◽  
Enhancer Activity ◽  
Single Nucleotide ◽  
Luciferase Activity Assay

Aim: To investigate the associations between single nucleotide polymorphisms (SNPs) in miRNA regulome and nonsyndromic orofacial clefts. Materials & methods: The associations were evaluated by logistic regression model in stage I (504 cases and 455 controls) and stage II (1500 cases and 1386 controls). Functional experiments including luciferase activity assay, cell apoptosis and proliferation, serum miRNA expression, and mouse embryo RNA sequencing were performed. Results: Rs3830766 in the enhancer of hsa-miR-4260 was associated with cleft lip only (CLO) and enhancer activity. Hsa-miR-4260 expression decreased in the serum of CLO. Overexpression of miR-4260 inhibited cell proliferation and promoted cell apoptosis. UBB was the target gene of hsa-miR-4260. Conclusion: Rs3830766 in the hsa-miR-4260 enhancer that can interact with UBB was relevant to CLO.

Characteristics of Electrically Evoked Somatodendritic Dopamine Release in Substantia Nigra and Ventral Tegmental Area In Vitro

1997 ◽  
Vol 77 (2) ◽  
pp. 853-862 ◽  
Author(s):  
M. E. Rice ◽  
S. J. Cragg ◽  
S. A. Greenfield
Keyword(s):  
Electrical Stimulation ◽  
Substantia Nigra ◽  
Ventral Tegmental Area ◽  
Dopamine Release ◽  
Substantia Nigra Pars Compacta ◽  
Frequency Dependent ◽  
Body Regions ◽  
Ventral Tegmental ◽  
Da Release

Rice, M. E., S. J. Cragg, and S. A. Greenfield. Characteristics of electrically evoked somatodendritic dopamine release in substantia nigra and ventral tegmental area in vitro. J. Neurophysiol. 77: 853–862, 1997. Somatodendritic dopamine (DA) release from neurons of the midbrain represents a nonclassical form of neuronal signaling. We assessed characteristics of DA release during electrical stimulation of the substantia nigra pars compacta (SNc) in guinea pig midbrain slices. With the use of parameters optimized for this region, we compared stimulus-induced increases in extracellular DA concentration ([DA]o) in medial and lateral SNc, ventral tegmental area (VTA), and dorsal striatum in vitro. DA release was monitored directly with carbon-fiber microelectrodes and fast-scan cyclic voltammetry. Detection of DA in SNc was confirmed by electrochemical, pharmacological, and anatomic criteria. Voltammograms of the released substance had the same peak potentials as those of DA obtained during in vitro calibration, but different from those of the indoleamine 5-hydroxytryptamine. Similar voltammograms were also obtained in the DA-rich striatum during local electrical stimulation. Contribution from the DA metabolite 3,4-dihydroxyphenylacetic acid to somatodendritic release was negligible, as indicated by the lack of effect of the monoamine oxidase inhibitor pargyline (20 μM) on the signal. Lastly, DA voltammograms could only be elicited in regions that were subsequently determined to be positive for tyrosine hydroxylase immunoreactivity (TH-ir). The frequency dependence of stimulated DA release in SNc was determined over a range of 1–50 Hz, with a constant duration of 10 s. Release was frequency dependent up to 10 Hz, with no further increase at higher frequencies. Stimulation at 10 Hz was used in all subsequent experiments. With this paradigm, DA release in SNc was tetrodotoxin insensitive, but strongly Ca2+ dependent. Stimulated [DA]o in the midbrain was also site specific. At the midcaudal level examined, DA efflux was significantly greater in VTA (1.04 ± 0.05 μM, mean ± SE) than in medial SNc (0.52 ± 0.05 μM), which in turn was higher than in lateral SNc (0.35 ± 0.03 μM). This pattern followed the apparent density of TH-ir, which was also VTA > medial SNc > lateral SNc. This report has introduced a new paradigm for the study of somatodendritic DA release. Voltammetric recording with electrodes of 2–4 μm tip diameter permitted highly localized, direct detection of endogenous DA. The Ca2+ dependence of stimulated release indicated that the process was physiologically relevant. Moreover, the findings that somatodendritic release was frequency dependent across a range characteristic of DA cell firing rates and that stimulated [DA]o varied markedly among DA cell body regions have important implications for how dendritically released DA may function in the physiology and pathophysiology of substantia nigra and VTA.

scholarly journals ZNF139 increases multidrug resistance in gastric cancer cells by inhibiting miR-185

2018 ◽  
Vol 38 (5) ◽  
Author(s):  
Bibo Tan ◽  
Yong Li ◽  
Qun Zhao ◽  
Liqiao Fan ◽  
Dong Wang
Keyword(s):  
Gastric Cancer ◽  
Drug Resistance ◽  
Multidrug Resistance ◽  
Cell Lines ◽  
Zinc Finger Protein ◽  
Luciferase Activity ◽  
Cell Activity ◽  
Expression Level ◽  
Activity Assay ◽  
Luciferase Activity Assay

It has been reported that the expression of zinc finger protein 139 (ZNF139) and microRNA-185 (miR-185) were associated with proliferation, drug resistance of gastric cancer (GC) cells. However, the detailed mechanisms have not been fully investigated. The expression of ZNF139 in both GC tissues and cell lines was tested, then SGC7901/ADR or SGC7901 cells were transfected with ZNF139-siRNA, miR-185 analog, or pcDNA-ZNF139. Cell activity was determined by MTT assay. Real-time PCR and Western blot were utilized to detect ZNF139, miR-185, and multidrug resistance (MDR) related genes including MDR1/P-gp, GST-π, MRP-1, Bcl-2, TS and Bax. ChIP and dual luciferase activity assay were used to investigate regulation between ZNF139 and miR-185. Increased ZNF139 and decreased miR-185 expression were detected in GC tissues and cell lines. Transfection with ZNF139-siRNA into SGC7901/ADR cells markedly increased expression of miR-185, and treating with chemotherapeutic drugs ADR, 5-FU, L-OHP, the survival rate of SGC7901/ADR cells obviously decreased after ZNF139-siRNA transfection. On the other hand, transfection with pcDNA-ZNF139 in GC cell line SGC7901 resulted in an increased expression level of ZNF139 and a decline in the expression level of miR-185, meanwhile drug resistance of GC cells was clearly enhanced to ADR, 5-FU, L-OHP. Dual luciferase activity assay demonstrated that ZNF139 inhibited transcriptional activities of miR-185’s promoter in cells transfected with the reporter plasmid encompassing the upstream promoter region of miR-185 along with pcDNA-ZNF139. Our data reveal that ZNF139 might promote MDR gene MDR1/P-gp, MRP-1 and Bcl-2 by prohibiting miR-185.

miR-628-5p promotes growth and migration of osteosarcoma by targeting IFI44L

2020 ◽  
Vol 98 (2) ◽  
pp. 99-105 ◽  
Author(s):  
Ju-Yong Wang ◽  
Ju-Qiang Wang ◽  
Shi-Bao Lu
Keyword(s):  
Untranslated Region ◽  
Poor Prognosis ◽  
Luciferase Activity ◽  
Gene Expression Omnibus ◽  
Migration And Invasion ◽  
Activity Assay ◽  
Luciferase Activity Assay ◽  
And Migration ◽  
Geo Database

This study investigated the role of miR-628-5p and interferon-induced protein 44-like (IFI44L) in osteosarcoma (OS) and determined whether miR-628-5p modulated OS growth by regulating IFI44L. Based on the data downloaded from Gene Expression Omnibus (GEO) database, we revealed that the expression of IFI44L was downregulated in OS and low expression of IFI44L was correlated with better prognosis of patients with OS. Biological prediction of its upstream regulatory miRNAs on the miRWalk website found that miR-628-5p is a possible upstream regulatory miRNA of IFI44L. Luciferase activity assay demonstrated that miR-628-5p could bind to the 3′ untranslated region (UTR) of IFI44L, which proved the above prediction. The expression of miR-628-5p is upregulated in OS and high expression of miR-628-5p is correlated with poor prognosis of patients with OS. The results of RT-qPCR showed that the expression of miR-628-5p in MG-63, U2OS, Saos-2, and SW1353 cells was significantly higher than that in the hFOB1.19 cells. Downregulation of miR-628-5p by miR-628-5p inhibitor significantly inhibited the proliferation, migration, and invasion of MG-63 cells. By rescue assay, we found that knockdown of IFI44L rescued the proliferation and motility of miR-628-5p depleted MG-63 cells. Collectively, our present data illustrated that miR-628-5p promoted the growth and motility of OS at least partly by targeting IFI44L. Moreover, miR-628-5p and IFI44L might be proposed as promising biomarkers in OS diagnosis and treatment.

scholarly journals The potassium channel KCa3.1 represents a valid pharmacological target for microgliosis-induced neuronal impairment in a mouse model of Parkinson’s disease

2019 ◽  
Vol 16 (1) ◽  
Author(s):  
Jia Lu ◽  
Fangfang Dou ◽  
Zhihua Yu
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Substantia Nigra ◽  
Mouse Model ◽  
Gene Deletion ◽  
Substantia Nigra Pars Compacta ◽  
Phenotype Switch ◽  
Pharmacological Blockade ◽  
Locomotor Ability

Abstract Background Recent studies described a critical role for microglia in Parkinson’s disease (PD), where these central nerve system resident immune cells participate in the neuroinflammatory microenvironment that contributes to dopaminergic neurons loss in the substantia nigra. Understanding the phenotype switch of microgliosis in PD could help to identify the molecular mechanism which could attenuate or delay the progressive decline in motor function. KCa3.1 has been reported to regulate the “pro-inflammatory” phenotype switch of microglia in neurodegenerative pathological conditions. Methods We here investigated the effects of gene deletion or pharmacological blockade of KCa3.1 activity in wild-type or KCa3.1−/− mice after treatment with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), a mouse model of PD. MPTP-induced PD mouse model was subjected to the rotarod test to evaluate the locomotor ability. Glia activation and neuron loss were measured by immunostaining. Fluo-4 AM was used to measure cytosolic Ca2+ level in 1-methyl-4-phenylpyridinium (MPP+)-induced microgliosis in vitro. Results We report that treatment of MPTP-induced PD mouse model with gene deletion or pharmacological blockade of KCa3.1 with senicapoc improves the locomotor ability and the tyrosine hydroxylase (TH)-positive neuron number and attenuates the microgliosis and neuroinflammation in the substantia nigra pars compacta (SNpc). KCa3.1 involves in store-operated Ca2+ entry-induced Ca2+ overload and endoplasmic reticulum stress via the protein kinase B (AKT) signaling pathway during microgliosis. Gene deletion or blockade of KCa3.1 restored AKT/mammalian target of rapamycin (mTOR) signaling both in vivo and in vitro. Conclusions Taken together, these results demonstrate a key role for KCa3.1 in driving a pro-inflammatory microglia phenotype in PD.

Subthalamic Stimulation-Induced Synaptic Responses in Substantia Nigra Pars Compacta Dopaminergic Neurons In Vitro

1999 ◽  
Vol 82 (2) ◽  
pp. 925-933 ◽  
Author(s):  
Yuji Iribe ◽  
Kevin Moore ◽  
Kevin C. H. Pang ◽  
James M. Tepper
Keyword(s):  
Substantia Nigra ◽  
Glutamate Receptor ◽  
Dopaminergic Neurons ◽  
Reversal Potential ◽  
Substantia Nigra Pars Compacta ◽  
Inhibitory Effects ◽  
Synaptic Potentials ◽  
Stimulation Of ◽  
Synaptic Responses

The subthalamic nucleus (STN) is one of the principal sources of excitatory glutamatergic input to dopaminergic neurons of the substantia nigra, yet stimulation of the STN produces both excitatory and inhibitory effects on nigral dopaminergic neurons recorded extracellularly in vivo. The present experiments were designed to determine the sources of the excitatory and inhibitory effects. Synaptic potentials were recorded intracellularly from substantia nigra pars compacta dopaminergic neurons in parasagittal slices in response to stimulation of the STN. Synaptic potentials were analyzed for onset latency, amplitude, duration, and reversal potential in the presence and absence of GABA and glutamate receptor antagonists. STN-evoked depolarizing synaptic responses in dopaminergic neurons reversed at approximately −31 mV, intermediate between the expected reversal potential for an excitatory and an inhibitory postsynaptic potential (EPSP and IPSP). Blockade of GABAA receptors with bicuculline caused a positive shift in the reversal potential to near 0 mV, suggesting that STN stimulation evoked a near simultaneous EPSP and IPSP. Both synaptic responses were blocked by application of the glutamate receptor antagonist, 6-cyano-7-nitroquinoxalene-2,3-dione. The confounding influence of inhibitory fibers of passage from globus pallidus and/or striatum by STN stimulation was eliminated by unilaterally transecting striatonigral and pallidonigral fibers 3 days before recording. The reversal potential of STN-evoked synaptic responses in dopaminergic neurons in slices from transected animals was approximately −30 mV. Bath application of bicuculline shifted the reversal potential to ∼5 mV as it did in intact animals, suggesting that the source of the IPSP was within substantia nigra. These data indicate that electrical stimulation of the STN elicits a mixed EPSP-IPSP in nigral dopaminergic neurons due to the coactivation of an excitatory monosynaptic and an inhibitory polysynaptic connection between the STN and the dopaminergic neurons of substantia nigra pars compacta. The EPSP arises from a direct monosynaptic excitatory glutamatergic input from the STN. The IPSP arises polysynaptically, most likely through STN-evoked excitation of GABAergic neurons in substantia nigra pars reticulata, which produces feed-forward GABAA-mediated inhibition of dopaminergic neurons through inhibitory intranigral axon collaterals.

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