IN VITRO GNAO1-ENCEPHALOPATHY MODEL DEVELOPMENT USING RECOMBINANT ADENO-ASSOCIATED VIRUSES

2020 ◽  
pp. 99-100
Keyword(s):  
Rna Interference ◽  
Model Development ◽  
Neuronal Culture ◽  
Wild Type ◽  
Primary Neuronal Culture ◽  
Neuronal Expression

Our study presents the verification of recombinant adeno-associated viruses on primary neuronal culture for GNAO1-encephalopathy modeling. We demonstrated neuronal expression of transgenic mutant and wild-type forms of the GNAO1. Downregulation by two-fold of the endogenous GNAO1 in neurons was achieved using RNA interference approach.

scholarly journals Systematic quantification of synapses in primary neuronal culture

2020 ◽  
Author(s):  
Peter Verstraelen ◽  
Gerardo Garcia ◽  
Marlies Verschuuren ◽  
Bob Asselbergh ◽  
Rony Nuydens ◽  
...  
Keyword(s):  
Synapse Formation ◽  
Dynamic Range ◽  
Cortical Cell ◽  
Neuronal Culture ◽  
Maturity Stage ◽  
Primary Neuronal Culture ◽  
Synaptic Markers ◽  
Synapse Density ◽  
Cortical Cell Cultures

AbstractA vast set of neurological disorders is associated with impaired synaptic connectivity. Therefore, modulation of synapse formation could have therapeutic relevance. However, the high density and small size of synapses make their quantification a challenging task. To improve the reliability of synapse-oriented drug screens, we evaluated a panel of synapse-targeting antibodies for their labeling specificity on hippocampal and cortical cell cultures using quantitative immunofluorescence microscopy. For those antibodies that passed multiparametric validation, we assessed pairwise colocalization, an often-used readout for established synapses. We found that even when two pan-synaptic markers were used, the overlap was incomplete, and the presence of spurious signals limited the dynamic range. To circumvent this problem, we implemented a proximity ligation-based approach, that only leads to a signal when two pre- and postsynaptic markers are sufficiently close. We demonstrate that this approach can be applied to different synaptic marker combinations and can be successfully used for quantification of synapse density in cultures of different maturity stage in healthy or pathological conditions. Thus, the unbiased analysis of synapse labeling and exploitation of resident protein proximity, allows increasing the sensitivity of synapse quantifications in neuronal culture and therefore represents a valuable extension of the analytical toolset for in vitro synapse screens.

scholarly journals Sequestration and Protection of Double-Stranded RNA by the Betanodavirus B2 Protein

2006 ◽  
Vol 80 (14) ◽  
pp. 6822-6833 ◽  
Author(s):  
Beau J. Fenner ◽  
Winnie Goh ◽  
Jimmy Kwang
Keyword(s):  
Rna Interference ◽  
Rna Virus ◽  
Interferon Response ◽  
Wild Type ◽  
Virus Family ◽  
Double Stranded Rna ◽  
Dsrna Binding ◽  
Sense Strand ◽  
Fish Cells

ABSTRACT Betanodavirus B2 belongs to a group of functionally related proteins from the sense-strand RNA virus family Nodaviridae that suppress cellular RNA interference. The B2 proteins of insect alphanodaviruses block RNA interference by binding to double-stranded RNA (dsRNA), thus preventing Dicer-mediated cleavage and the subsequent generation of short interfering RNAs. We show here that the fish betanodavirus B2 protein also binds dsRNA. Binding is sequence independent, and maximal binding occurs with dsRNA substrates greater than 20 bp in length. The binding of B2 to long dsRNA is sufficient to completely block Dicer cleavage of dsRNA in vitro. Protein-protein interaction studies indicated that B2 interacts with itself and with other dsRNA binding proteins, the interaction occurring through binding to shared dsRNA substrates. Induction of the dsRNA-dependent interferon response was not antagonized by B2, as the interferon-responsive Mx gene of permissive fish cells was induced by wild-type viral RNA1 but not by a B2 mutant. The induction of Mx instead relied solely on viral RNA1 accumulation, which is impaired in the B2 mutant. Hyperediting of virus dsRNA and site-specific editing of 5-HT2C mRNA were both antagonized by B2. RNA editing was not, however, observed in transfected wild-type or B2 mutant RNA1, suggesting that this pathway does not contribute to the RNA1 accumulation defect of the B2 mutant. We thus conclude that betanodavirus B2 is a dsRNA binding protein that sequesters and protects both long and short dsRNAs to protect betanodavirus from cellular RNA interference.

scholarly journals Phosphorylation- and Polo-Box–dependent Binding of Plk1 to Bub1 Is Required for the Kinetochore Localization of Plk1

2006 ◽  
Vol 17 (8) ◽  
pp. 3705-3716 ◽  
Author(s):  
Wei Qi ◽  
Zhanyun Tang ◽  
Hongtao Yu
Keyword(s):  
Rna Interference ◽  
Hela Cells ◽  
Ectopic Expression ◽  
Spindle Checkpoint ◽  
Human Cells ◽  
Docking Site ◽  
Cyclin Dependent Kinase ◽  
Wild Type ◽  
Checkpoint Proteins

Polo-like kinase 1 (Plk1) is required for the generation of the tension-sensing 3F3/2 kinetochore epitope and facilitates kinetochore localization of Mad2 and other spindle checkpoint proteins. Here, we investigate the mechanism by which Plk1 itself is recruited to kinetochores. We show that Plk1 binds to budding uninhibited by benzimidazole 1 (Bub1) in mitotic human cells. The Plk1–Bub1 interaction requires the polo-box domain (PBD) of Plk1 and is enhanced by cyclin-dependent kinase 1 (Cdk1)-mediated phosphorylation of Bub1 at T609. The PBD-dependent binding of Plk1 to Bub1 facilitates phosphorylation of Bub1 by Plk1 in vitro. Depletion of Bub1 in HeLa cells by RNA interference (RNAi) diminishes the kinetochore localization of Plk1. Ectopic expression of the wild-type Bub1, but not the Bub1-T609A mutant, in Bub1-RNAi cells restores the kinetochore localization of Plk1. Our results suggest that phosphorylation of Bub1 at T609 by Cdk1 creates a docking site for the PBD of Plk1 and facilitates the kinetochore recruitment of Plk1.

RNA interference and its clinical applications

2007 ◽  
Vol 148 (47) ◽  
pp. 2235-2240 ◽  
Author(s):  
Gyöngyi Munkácsy ◽  
Zsolt Tulassay ◽  
Balázs Győrffy
Keyword(s):  
Rna Interference ◽  
Clinical Applications

Az RNS-interferencia a poszttranszkripciós génelcsendesítés olyan formája, amelynek során rövid, specifikusan RNS-molekulák elnyomják a gének kifejeződésében kulcsszerepet játszó hírvivő RNS-ek működését. A sejtbe juttatott dupla szálú vagy rövid interferáló RNS-molekulák aktiválják az RNS-indukált elcsendesítő komplexet, amely a célgén hírvivő RNS-ét lebontja. A sejtek saját szabályozó mikro-RNS-molekulákkal is rendelkeznek, amelyeknek hírvivő RNS-e képes önmagával hajtűt képezni, amit a sejt dupla szálú RNS-ként értelmez. Az RNS-interferencia élettani működései közé tartozik a vírusok és a transzpozonok elleni védekezés, valamint a génkifejeződés szabályozása. Az RNS-interferencia nemcsak in vitro alkalmazható az egyes gének működésének vizsgálatára, hanem klinikai alkalmazásainak lehetőségei is megjelentek. Eddig vírusfertőzésekben, az időskori makuladegeneráció gátlására, a vér koleszterinszint-csökkentésére, daganatellenes és neurodegeneratív betegségek kezelésében alkalmazták. Az RNS-interferencia alkalmazását azonban nehezíti, hogy a megfelelő rövid interferáló RNS-molekulák tervezéséhez szükséges bioinformatikai algoritmusok nem tökéletesek; a szervezet szöveteibe való bejuttatásuk nehéz; illetve csak olyan esetekben alkalmazható, amelyekben átmeneti antagonista génelcsendesítő hatás és nem hosszú távú kezelés szükséges. Az alkalmazás legnagyobb előnye a jelentős specificitás, ami miatt mellékhatása is kevés. Az RNS-interferencia alapú kezelések megjelenése már a közeli jövőben várható.

The URNA Genes of Herpesvirus Saimiri (Strain C488) Are Dispensable for Transformation of Human T Cells In Vitro

1999 ◽  
Vol 73 (12) ◽  
pp. 10551-10555 ◽  
Author(s):  
Armin Ensser ◽  
André Pfinder ◽  
Ingrid Müller-Fleckenstein ◽  
Bernhard Fleckenstein
Keyword(s):  
Cell Culture ◽  
Herpesvirus Saimiri ◽  
Wild Type Virus ◽  
Type Virus ◽  
Wild Type ◽  
Human T Cell ◽  
Human T Cells ◽  
Small Nuclear Rnas ◽  
T Cell Lines

ABSTRACT The herpesvirus saimiri strain C488 genome contains five genes for small nuclear RNAs, termed herpesvirus saimiri URNAs (or HSURs). Using a cosmid-based approach, all HSURs were precisely deleted from the genome. The mutant virus replicated at levels that were similar to those of wild-type viruses in OMK cells. Although the HSURs are expressed in wild-type virus-transformed human T-cell lines, the deletion does not affect viral transformation in cell culture.

scholarly journals Mutations in fbiD (Rv2983) as a Novel Determinant of Resistance to Pretomanid and Delamanid in Mycobacterium tuberculosis

2020 ◽  
Vol 65 (1) ◽  
pp. e01948-20
Author(s):  
Dalin Rifat ◽  
Si-Yang Li ◽  
Thomas Ioerger ◽  
Keshav Shah ◽  
Jean-Philippe Lanoix ◽  
...  
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Clinical Evidence ◽  
Clinical Samples ◽  
Loss Of Function ◽  
Wild Type ◽  
Content Type ◽  
Solid Media ◽  
High Level ◽  
Level Resistance

ABSTRACTThe nitroimidazole prodrugs delamanid and pretomanid comprise one of only two new antimicrobial classes approved to treat tuberculosis (TB) in 50 years. Prior in vitro studies suggest a relatively low barrier to nitroimidazole resistance in Mycobacterium tuberculosis, but clinical evidence is limited to date. We selected pretomanid-resistant M. tuberculosis mutants in two mouse models of TB using a range of pretomanid doses. The frequency of spontaneous resistance was approximately 10−5 CFU. Whole-genome sequencing of 161 resistant isolates from 47 mice revealed 99 unique mutations, of which 91% occurred in 1 of 5 genes previously associated with nitroimidazole activation and resistance, namely, fbiC (56%), fbiA (15%), ddn (12%), fgd (4%), and fbiB (4%). Nearly all mutations were unique to a single mouse and not previously identified. The remaining 9% of resistant mutants harbored mutations in Rv2983 (fbiD), a gene not previously associated with nitroimidazole resistance but recently shown to be a guanylyltransferase necessary for cofactor F420 synthesis. Most mutants exhibited high-level resistance to pretomanid and delamanid, although Rv2983 and fbiB mutants exhibited high-level pretomanid resistance but relatively small changes in delamanid susceptibility. Complementing an Rv2983 mutant with wild-type Rv2983 restored susceptibility to pretomanid and delamanid. By quantifying intracellular F420 and its precursor Fo in overexpressing and loss-of-function mutants, we provide further evidence that Rv2983 is necessary for F420 biosynthesis. Finally, Rv2983 mutants and other F420H2-deficient mutants displayed hypersusceptibility to some antibiotics and to concentrations of malachite green found in solid media used to isolate and propagate mycobacteria from clinical samples.

scholarly journals InsP7is a small-molecule regulator of NUDT3-mediated mRNA decapping and processing-body dynamics

2020 ◽  
Vol 117 (32) ◽  
pp. 19245-19253 ◽  
Author(s):  
Soumyadip Sahu ◽  
Zhenzhen Wang ◽  
Xinfu Jiao ◽  
Chunfang Gu ◽  
Nikolaus Jork ◽  
...  
Keyword(s):  
Stress Responses ◽  
Messenger Rna ◽  
Control Process ◽  
Stem Cell Differentiation ◽  
Wild Type ◽  
Inositol Pyrophosphate ◽  
Body Dynamics ◽  
Processing Body ◽  
The Stability

Regulation of enzymatic 5′ decapping of messenger RNA (mRNA), which normally commits transcripts to their destruction, has the capacity to dynamically reshape the transcriptome. For example, protection from 5′ decapping promotes accumulation of mRNAs into processing (P) bodies—membraneless, biomolecular condensates. Such compartmentalization of mRNAs temporarily removes them from the translatable pool; these repressed transcripts are stabilized and stored until P-body dissolution permits transcript reentry into the cytosol. Here, we describe regulation of mRNA stability and P-body dynamics by the inositol pyrophosphate signaling molecule 5-InsP7(5-diphosphoinositol pentakisphosphate). First, we demonstrate 5-InsP7inhibits decapping by recombinant NUDT3 (Nudix [nucleoside diphosphate linked moiety X]-type hydrolase 3) in vitro. Next, in intact HEK293 and HCT116 cells, we monitored the stability of a cadre of NUDT3 mRNA substrates following CRISPR-Cas9 knockout ofPPIP5Ks(diphosphoinositol pentakisphosphate 5-kinases type 1 and 2, i.e.,PPIP5KKO), which elevates cellular 5-InsP7levels by two- to threefold (i.e., within the physiological rheostatic range). ThePPIP5KKO cells exhibited elevated levels of NUDT3 mRNA substrates and increased P-body abundance. Pharmacological and genetic attenuation of 5-InsP7synthesis in the KO background reverted both NUDT3 mRNA substrate levels and P-body counts to those of wild-type cells. Furthermore, liposomal delivery of a metabolically resistant 5-InsP7analog into wild-type cells elevated levels of NUDT3 mRNA substrates and raised P-body abundance. In the context that cellular 5-InsP7levels normally fluctuate in response to changes in the bioenergetic environment, regulation of mRNA structure by this inositol pyrophosphate represents an epitranscriptomic control process. The associated impact on P-body dynamics has relevance to regulation of stem cell differentiation, stress responses, and, potentially, amelioration of neurodegenerative diseases and aging.

scholarly journals Allelic Exchange and Mutant Selection Demonstrate that Common Clinical embCAB Gene Mutations Only Modestly Increase Resistance to Ethambutol in Mycobacterium tuberculosis

2009 ◽  
Vol 54 (1) ◽  
pp. 103-108 ◽  
Author(s):  
Hassan Safi ◽  
Robert D. Fleischmann ◽  
Scott N. Peterson ◽  
Marcus B. Jones ◽  
Behnam Jarrahi ◽  
...  
Keyword(s):  
Mycobacterium Tuberculosis ◽  
In Vitro Selection ◽  
Gene Mutations ◽  
Wild Type ◽  
Mutant Selection ◽  
Preferential Growth ◽  
Allelic Exchange ◽  
High Level ◽  
Isogenic Mutants

ABSTRACT Mutations within codon 306 of the Mycobacterium tuberculosis embB gene modestly increase ethambutol (EMB) MICs. To identify other causes of EMB resistance and to identify causes of high-level resistance, we generated EMB-resistant M. tuberculosis isolates in vitro and performed allelic exchange studies of embB codon 406 (embB406) and embB497 mutations. In vitro selection produced mutations already identified clinically in embB306, embB397, embB497, embB1024, and embC13, which result in EMB MICs of 8 or 14 μg/ml, 5 μg/ml, 12 μg/ml, 3 μg/ml, and 4 μg/ml, respectively, and mutations at embB320, embB324, and embB445, which have not been identified in clinical M. tuberculosis isolates and which result in EMB MICs of 8 μg/ml, 8 μg/ml, and 2 to 8 μg/ml, respectively. To definitively identify the effect of the common clinical embB497 and embB406 mutations on EMB susceptibility, we created a series of isogenic mutants, exchanging the wild-type embB497 CAG codon in EMB-susceptible M. tuberculosis strain 210 for the embB497 CGG codon and the wild-type embB406 GGC codon for either the embB406 GCC, embB406 TGC, embB406 TCC, or embB406 GAC codon. These new mutants showed 6-fold and 3- to 3.5-fold increases in the EMB MICs, respectively. In contrast to the embB306 mutants, the isogenic embB497 and embB406 mutants did not have preferential growth in the presence of isoniazid or rifampin (rifampicin) at their MICs. These results demonstrate that individual embCAB mutations confer low to moderate increases in EMB MICs. Discrepancies between the EMB MICs of laboratory mutants and clinical M. tuberculosis strains with identical mutations suggest that clinical EMB resistance is multigenic and that high-level EMB resistance requires mutations in currently unknown loci.

scholarly journals Wild type GAL4 binds cooperatively to the GAL1-10 UASG in vitro

1993 ◽  
Vol 268 (13) ◽  
pp. 9629-9635
Author(s):  
T. Kang ◽  
T. Martins ◽  
I. Sadowski
Keyword(s):  
Wild Type
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