receptor editing Dotaz Zobrazit nápovědu
Avian leukosis viruses (ALVs), which are pathogens of concern in domestic poultry, utilize specific receptor proteins for cell entry that are both necessary and sufficient for host susceptibility to a given ALV subgroup. This unequivocal relationship offers receptors as suitable targets of selection and biotechnological manipulation with the aim of obtaining virus-resistant poultry. This approach is further supported by the existence of natural knock-outs of receptor genes that segregate in inbred lines of chickens. We used CRISPR/Cas9 genome editing tools to introduce frame-shifting indel mutations into tva, tvc, and tvj loci encoding receptors for the A, C, and J ALV subgroups, respectively. For all three loci, the homozygous frame-shifting indels generating premature stop codons induced phenotypes which were fully resistant to the virus of respective subgroup. In the tvj locus, we also obtained in-frame deletions corroborating the importance of W38 and the four amino-acids preceding it. We demonstrate that CRISPR/Cas9-mediated knock-out or the fine editing of ALV receptor genes might be the first step in the development of virus-resistant chickens.
- MeSH
- buněčné linie MeSH
- CRISPR-Cas systémy * MeSH
- editace genu * MeSH
- genetické techniky MeSH
- genetické vektory genetika MeSH
- guide RNA, Kinetoplastida MeSH
- kur domácí MeSH
- odolnost vůči nemocem genetika MeSH
- ptačí leukóza genetika virologie MeSH
- sekvence nukleotidů MeSH
- virové geny MeSH
- virové receptory genetika metabolismus MeSH
- virus ptačí leukózy fyziologie MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
In eukaryotes mRNA transcripts are extensively processed by different post-transcriptional events such as alternative splicing and RNA editing in order to generate many different mRNAs from the same gene, increasing the transcriptome and then the proteome diversity. The most frequent RNA editing mechanism in mammals involves the conversion of specific adenosines into inosines by the ADAR family of enzymes. This editing event can alter the sequence and the secondary structure of RNA molecules, with consequences for final proteins and regulatory RNAs. Alteration in RNA editing has been connected to tumor progression and many other important human diseases. Analysis of many editing sites in various cancer types is expected to provide new diagnostic and prognostic markers and might contribute to early detection of cancer, the monitoring of response to therapy, and to the detection of minimal residual disease.
- MeSH
- adenosindeaminasa genetika chemie metabolismus MeSH
- apolipoprotein B-100 chemie metabolismus MeSH
- apolipoprotein B-48 chemie metabolismus MeSH
- editace RNA fyziologie genetika MeSH
- glutamátové receptory chemie metabolismus MeSH
- lidé MeSH
- messenger RNA chemie metabolismus MeSH
- nádory metabolismus MeSH
- tyrosinfosfatasy metabolismus MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- přehledy MeSH
- publikace stažené z tisku MeSH
Adenosine deaminases acting on RNA (ADARs) convert adenosine to inosine in dsRNA. ADAR editing in pre-mRNAs recodes open reading frames and alters splicing, mRNA structure and interactions with miRNAs. Here, we review ADAR gene expression, splice forms, posttranslational modifications, subcellular localizations and functions of ADAR protein isoforms. ADAR1 edits cellular dsRNA to prevent aberrant activation of cytoplasmic antiviral dsRNA sensors; ADAR1 mutations lead to aberrant expression of interferon in Aicardi Goutières syndrome (AGS), a human congenital encephalopathy. We review related studies on mouse Adar1 mutant phenotypes, their rescues by preventing signaling from the antiviral RIG-I-like Sensors (RLRs), as well as Adar1 mechanisms in innate immune suppression and other roles of Adar1, including editing-independent effects. ADAR2, expressed primarily in CNS, edits glutamate receptor transcripts; regulation of ADAR2 activity in response to neuronal activity mediates homeostatic synaptic plasticity of vertebrate AMPA and kainite receptors. In Drosophila, synapses and synaptic proteins show dramatic decreases at night during sleep; Drosophila Adar, an orthologue of ADAR2, edits hundreds of mRNAs; the most conserved editing events occur in transcripts encoding synapse-associated proteins. Adar mutant flies exhibit locomotion defects associated with very increased sleep pressure resulting from a failure of homeostatic synaptic processes. A study on Adar2 mutant mice identifies a new role in circadian rhythms, acting indirectly through miRNAs such as let-7 to modulate levels of let-7 target mRNAs; ADAR1 also regulates let-7 miRNA processing. Drosophila ADAR, an orthologue of vertebrate ADAR2, also regulates let-7 miRNA levels and Adar mutant flies have a circadian mutant phenotype.
- MeSH
- adenosindeaminasa genetika metabolismus MeSH
- cirkadiánní hodiny * MeSH
- editace RNA * MeSH
- lidé MeSH
- přirozená imunita * MeSH
- spánek * MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
We review the structures and functions of ADARs and their involvements in human diseases. ADAR1 is widely expressed, particularly in the myeloid component of the blood system, and plays a prominent role in promiscuous editing of long dsRNA. Missense mutations that change ADAR1 residues and reduce RNA editing activity cause Aicardi-Goutières Syndrome, a childhood encephalitis and interferonopathy that mimics viral infection and resembles an extreme form of Systemic Lupus Erythmatosus (SLE). In Adar1 mouse mutant models aberrant interferon expression is prevented by eliminating interferon activation signaling from cytoplasmic dsRNA sensors, indicating that unedited cytoplasmic dsRNA drives the immune induction. On the other hand, upregulation of ADAR1 with widespread promiscuous RNA editing is a prominent feature of many cancers and particular site-specific RNA editing events are also affected. ADAR2 is most highly expressed in brain and is primarily required for site-specific editing of CNS transcripts; recent findings indicate that ADAR2 editing is regulated by neuronal excitation for synaptic scaling of glutamate receptors. ADAR2 is also linked to the circadian clock and to sleep. Mutations in ADAR2 could contribute to excitability syndromes such as epilepsy, to seizures, to diseases involving neuronal plasticity defects, such as autism and Fragile-X Syndrome, to neurodegenerations such as ALS, or to astrocytomas or glioblastomas in which reduced ADAR2 activity is required for oncogenic cell behavior. The range of human disease associated with ADAR1 mutations may extend further to include other inflammatory conditions while ADAR2 mutations may affect psychiatric conditions.
- MeSH
- adenosindeaminasa * genetika metabolismus MeSH
- duševní poruchy * genetika metabolismus MeSH
- dvouvláknová RNA * genetika metabolismus MeSH
- editace RNA genetika MeSH
- lidé MeSH
- mutace * MeSH
- mutantní kmeny myší MeSH
- myši MeSH
- nemoci nervového systému * genetika metabolismus MeSH
- proteiny vázající RNA * genetika metabolismus MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
Avian leukosis virus subgroup J (ALV-J) is an important concern for the poultry industry. Replication of ALV-J depends on a functional cellular receptor, the chicken Na+/H+ exchanger type 1 (chNHE1). Tryptophan residue number 38 of chNHE1 (W38) in the extracellular portion of this molecule is a critical amino acid for virus entry. We describe a CRISPR/Cas9-mediated deletion of W38 in chicken primordial germ cells and the successful production of the gene-edited birds. The resistance to ALV-J was examined both in vitro and in vivo, and the ΔW38 homozygous chickens tested ALV-J-resistant, in contrast to ΔW38 heterozygotes and wild-type birds, which were ALV-J-susceptible. Deletion of W38 did not manifest any visible side effect. Our data clearly demonstrate the antiviral resistance conferred by precise CRISPR/Cas9 gene editing in the chicken. Furthermore, our highly efficient CRISPR/Cas9 gene editing in primordial germ cells represents a substantial addition to genotechnology in the chicken, an important food source and research model.
- MeSH
- CRISPR-Cas systémy MeSH
- editace genu MeSH
- geneticky modifikovaná zvířata genetika imunologie virologie MeSH
- kur domácí MeSH
- nemoci drůbeže genetika imunologie virologie MeSH
- odolnost vůči nemocem MeSH
- ptačí leukóza genetika imunologie virologie MeSH
- ptačí proteiny genetika imunologie MeSH
- sodíko-vodíkový výměnný transportér 1 genetika imunologie MeSH
- virus ptačí leukózy klasifikace genetika fyziologie MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
The chicken Tva cell surface protein, a member of the low-density lipoprotein receptor family, has been identified as an entry receptor for avian leukosis virus of classic subgroup A and newly emerging subgroup K. Because both viruses represent an important concern for the poultry industry, we introduced a frame-shifting deletion into the chicken tva locus with the aim of knocking-out Tva expression and creating a virus-resistant chicken line. The tva knock-out was prepared by CRISPR/Cas9 gene editing in chicken primordial germ cells and orthotopic transplantation of edited cells into the testes of sterilized recipient roosters. The resulting tva -/- chickens tested fully resistant to avian leukosis virus subgroups A and K, both in in vitro and in vivo assays, in contrast to their susceptible tva +/+ and tva +/- siblings. We also found a specific disorder of the cobalamin/vitamin B12 metabolism in the tva knock-out chickens, which is in accordance with the recently recognized physiological function of Tva as a receptor for cobalamin in complex with transcobalamin transporter. Last but not least, we bring a new example of the de novo resistance created by CRISPR/Cas9 editing of pathogen dependence genes in farm animals and, furthermore, a new example of gene editing in chicken.
- MeSH
- editace genu MeSH
- genový knockout MeSH
- kur domácí virologie MeSH
- kuřecí embryo MeSH
- kyselina methylmalonová krev MeSH
- posunová mutace MeSH
- ptačí proteiny genetika fyziologie MeSH
- virové receptory genetika fyziologie MeSH
- virus ptačí leukózy klasifikace fyziologie MeSH
- vitamin B 12 metabolismus MeSH
- zvířata MeSH
- Check Tag
- kuřecí embryo MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
RNA-guided, engineered nucleases derived from the prokaryotic adaptive immune system CRISPR-Cas represent a powerful platform for gene deletion and editing. When used as a therapeutic approach, direct delivery of Cas9 protein and single-guide RNA (sgRNA) could circumvent the safety issues associated with plasmid delivery and therefore represents an attractive tool for precision genome engineering. Gene deletion or editing in adipose tissue to enhance its energy expenditure, fatty acid oxidation, and secretion of bioactive factors through a "browning" process presents a potential therapeutic strategy to alleviate metabolic disease. Here, we developed "CRISPR-delivery particles," denoted CriPs, composed of nano-size complexes of Cas9 protein and sgRNA that are coated with an amphipathic peptide called Endo-Porter that mediates entry into cells. Efficient CRISPR-Cas9-mediated gene deletion of ectopically expressed GFP by CriPs was achieved in multiple cell types, including a macrophage cell line, primary macrophages, and primary pre-adipocytes. Significant GFP loss was also observed in peritoneal exudate cells with minimum systemic toxicity in GFP-expressing mice following intraperitoneal injection of CriPs containing Gfp-targeting sgRNA. Furthermore, disruption of a nuclear co-repressor of catabolism, the Nrip1 gene, in white adipocytes by CriPs enhanced adipocyte browning with a marked increase of uncoupling protein 1 (UCP1) expression. Of note, the CriP-mediated Nrip1 deletion did not produce detectable off-target effects. We conclude that CriPs offer an effective Cas9 and sgRNA delivery system for ablating targeted gene products in cultured cells and in vivo, providing a potential therapeutic strategy for metabolic disease.
- MeSH
- bílá tuková tkáň cytologie metabolismus MeSH
- buněčné linie MeSH
- CRISPR-Cas systémy MeSH
- editace genu MeSH
- energetický metabolismus * MeSH
- genový targeting metody MeSH
- lidé MeSH
- myši inbrední C57BL MeSH
- nuclear receptor interacting protein 1 genetika metabolismus MeSH
- plazmidy genetika metabolismus MeSH
- reportérové geny MeSH
- sekvence CRISPR MeSH
- tukové buňky metabolismus MeSH
- uncoupling protein 1 genetika metabolismus MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- hodnotící studie MeSH
- práce podpořená grantem MeSH
- Research Support, N.I.H., Extramural MeSH
The mammalian circadian system consists of a major circadian pacemaker located in the suprachiasmatic nucleus (SCN) of the hypothalamus and peripheral clocks in the body, including brain structures. The SCN depends on glutamatergic neurotransmission for transmitting signals from the retina, and it exhibits spontaneous 24-h rhythmicity in neural activity. The aim of this work was to evaluate the degree and circadian rhythmicity of AMPA receptor GluA2 subunit R/G editing and alternative flip/flop splicing in the SCN and other brain structures in Wistar rats. Our data show that the circadian rhythmicity in the SCN's GluA2 mRNA level was highest at dawn, while the circadian rhythm in R/G editing peaked at CT10 and the rhythmic flip varied with the acrophase at the late subjective night. The circadian rhythmicity was confirmed for R/G editing and splicing in the CA3 hippocampal area, and rhythmic variation of the flip isoform was also measured in the olfactory bulbs and cerebellum. The correlations between the R/G editing and alternative flip/flop splicing revealed a structure-dependent direction. In the hippocampus, the edited (G)-form level was positively correlated with the flip variant abundance, in accord with published data; by contrast, in the SCN, the flip variant was in associated more with the unedited (R) form. The edited (G) form and flop isoform also predominated in the retina and cerebellum.
- MeSH
- AMPA receptory genetika metabolismus MeSH
- cirkadiánní rytmus genetika MeSH
- editace RNA genetika MeSH
- exony genetika MeSH
- messenger RNA genetika metabolismus MeSH
- nucleus suprachiasmaticus metabolismus MeSH
- posttranskripční úpravy RNA genetika MeSH
- potkani Wistar MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Pregnane X receptor (PXR) is a major transcriptional regulator of xenobiotic metabolism and transport pathways in the liver and intestines, which are critical for protecting organisms against potentially harmful xenobiotic and endobiotic compounds. Inadvertent activation of drug metabolism pathways through PXR is known to contribute to drug resistance, adverse drug-drug interactions, and drug toxicity in humans. In both humans and rodents, PXR has been implicated in non-alcoholic fatty liver disease, diabetes, obesity, inflammatory bowel disease, and cancer. Because of PXR's important functions, it has been a therapeutic target of interest for a long time. More recent mechanistic studies have shown that PXR is modulated by multiple PTMs. Herein we provide the first investigation of the role of acetylation in modulating PXR activity. Through LC-MS/MS analysis, we identified lysine 109 (K109) in the hinge as PXR's major acetylation site. Using various biochemical and cell-based assays, we show that PXR's acetylation status and transcriptional activity are modulated by E1A binding protein (p300) and sirtuin 1 (SIRT1). Based on analysis of acetylation site mutants, we found that acetylation at K109 represses PXR transcriptional activity. The mechanism involves loss of RXRα dimerization and reduced binding to cognate DNA response elements. This mechanism may represent a promising therapeutic target using modulators of PXR acetylation levels. This article is part of a Special Issue entitled: Xenobiotic nuclear receptors: New Tricks for An Old Dog, edited by Dr. Wen Xie.
- MeSH
- acetylace MeSH
- aktivace transkripce * MeSH
- buňky Hep G2 MeSH
- DNA chemie metabolismus MeSH
- Escherichia coli genetika metabolismus MeSH
- HEK293 buňky MeSH
- HeLa buňky MeSH
- klonování DNA MeSH
- lidé MeSH
- luciferasy genetika metabolismus MeSH
- lysin chemie metabolismus MeSH
- molekulární modely MeSH
- multimerizace proteinu MeSH
- mutageneze cílená MeSH
- posttranslační úpravy proteinů * MeSH
- rekombinantní proteiny chemie genetika metabolismus MeSH
- reportérové geny MeSH
- responzivní elementy MeSH
- sekundární struktura proteinů MeSH
- sirtuin 1 genetika metabolismus MeSH
- steroidní receptory chemie genetika metabolismus MeSH
- strukturní homologie proteinů MeSH
- transkripční faktory p300-CBP genetika metabolismus MeSH
- vztahy mezi strukturou a aktivitou MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, N.I.H., Extramural MeSH
Anaplastic large cell lymphoma (ALCL) is a T-cell malignancy predominantly driven by a hyperactive anaplastic lymphoma kinase (ALK) fusion protein. ALK inhibitors, such as crizotinib, provide alternatives to standard chemotherapy with reduced toxicity and side effects. Children with lymphomas driven by nucleophosmin 1 (NPM1)-ALK fusion proteins achieved an objective response rate to ALK inhibition therapy of 54% to 90% in clinical trials; however, a subset of patients progressed within the first 3 months of treatment. The mechanism for the development of ALK inhibitor resistance is unknown. Through genome-wide clustered regularly interspaced short palindromic repeats (CRISPR) activation and knockout screens in ALCL cell lines, combined with RNA sequencing data derived from ALK inhibitor-relapsed patient tumors, we show that resistance to ALK inhibition by crizotinib in ALCL can be driven by aberrant upregulation of interleukin 10 receptor subunit alpha (IL10RA). Elevated IL10RA expression rewires the STAT3 signaling pathway, bypassing otherwise critical phosphorylation by NPM1-ALK. IL-10RA expression does not correlate with response to standard chemotherapy in pediatric patients, suggesting that a combination of crizotinib and chemotherapy could prevent ALK inhibitor resistance-specific relapse.
- MeSH
- anaplastický velkobuněčný lymfom farmakoterapie genetika metabolismus patologie MeSH
- antitumorózní látky farmakologie terapeutické užití MeSH
- biologické modely MeSH
- buněčné linie MeSH
- chemorezistence genetika MeSH
- CRISPR-Cas systémy MeSH
- editace genu MeSH
- exprese genu MeSH
- imunohistochemie MeSH
- inhibitory proteinkinas farmakologie terapeutické užití MeSH
- krizotinib farmakologie terapeutické užití MeSH
- lidé MeSH
- receptor interleukinu-10 - alfa-podjednotka genetika metabolismus MeSH
- signální transdukce účinky léků MeSH
- transkripční faktor STAT3 metabolismus MeSH
- tyrosinkinasy genetika metabolismus MeSH
- vztah mezi dávkou a účinkem léčiva MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH