Impaired fibroblast growth factor receptor (FGFR) signaling is associated with many human conditions, including growth disorders, degenerative diseases, and cancer. Current FGFR therapeutics are based on chemical inhibitors of FGFR tyrosine kinase activity (TKIs). However, FGFR TKIs are limited in their target specificity as they generally inhibit all FGFRs and other receptor tyrosine kinases. In the search for specific inhibitors of human FGFR1, we identified VZ23, a DNA aptamer that binds to FGFR1b and FGFR1c with a KD of 55 nM and 162 nM, respectively, but not to the other FGFR variants (FGFR2b, FGFR2c, FGFR3b, FGFR3c, FGFR4). In cells, VZ23 inhibited the activation of downstream FGFR1 signaling and FGFR1-mediated regulation of cellular senescence, proliferation, and extracellular matrix homeostasis. Consistent with the specificity toward FGFR1 observed in vitro, VZ23 did not inhibit FGFR2-4 signaling in cells. We show that the VZ23 inhibits FGFR1 signaling in the presence of cognate fibroblast growth factor (FGF) ligands and its inhibitory activity is linked to its capacity to form unusual G-quadruplex structure. Our data suggest that targeting FGFR1 with DNA aptamers could be an effective alternative to TKIs for treating impaired FGFR1 signaling in human craniosynostoses.
- Klíčová slova
- DNA aptamer, FGFR signaling, FGFR1, MT: Oligonucleotides: Therapies and Applications, craniosynostosis, extracellular domain, inhibitor, skeletal dysplasia,
- Publikační typ
- časopisecké články MeSH
ISG20L2, a 3' to 5' exoribonuclease previously associated with ribosome biogenesis, is identified here in activated T cells as an enzyme with a preferential affinity for uridylated miRNA substrates. This enzyme is upregulated in T lymphocytes upon TCR and IFN type I stimulation and appears to be involved in regulating T cell function. ISG20L2 silencing leads to an increased basal expression of CD69 and induces greater IL2 secretion. However, ISG20L2 absence impairs CD25 upregulation, CD3 synaptic accumulation and MTOC translocation towards the antigen-presenting cell during immune synapsis. Remarkably, ISG20L2 controls the expression of immunoregulatory molecules, such as AHR, NKG2D, CTLA-4, CD137, TIM-3, PD-L1 or PD-1, which show increased levels in ISG20L2 knockout T cells. The dysregulation observed in these key molecules for T cell responses support a role for this exonuclease as a novel RNA-based regulator of T cell function.
- Klíčová slova
- Exonuclease, ISG20L2, Immunoregulatory, T cell,
- MeSH
- aktivace lymfocytů * MeSH
- antigen prezentující buňky MeSH
- endonukleasy MeSH
- lidé MeSH
- mikro RNA * genetika MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- endonukleasy MeSH
- mikro RNA * MeSH
OBJECTIVE: The aim of the study was the genetic characterization of a set of cases with an unclear morphological profile of the placental tissue suspected of a partial hydatidiform mole. PATIENTS AND METHODS: This work presents the results of a genetic analysis of a group of 10 patients with various clinical manifestations of reproductive loss, where a partial hydatidiform mole was suspected on the basis of a histopathological examination. The composition of the genome of the products of conception was determined by short tandem repeats (STR) genotyping using a commercial kit;Devyser Compact v3 (Devyser). RESULTS AND CONCLUSIONS: Out of 10 analyzed cases, five had diandric monogynic triploid genome, characteristic for a partial mole. Aneuploidies of chromosomes 13, 18, 21, X and Y were excluded in four cases and Pataus syndrome was dia-gnosed in one case. In the case of an unclear histopathological profile, consultative DNA analysis (ideally STR genotyping) can significantly help the pathologist in the differential dia-gnosis of a partial mole. The histopathological profile of a partial hydatidiform mole may be in some cases incomplete and unclear, especially in the early weeks of gestation, which can lead to false negativity of the examination. On the other hand, other pathologies, for example aneuploides or digynic triploidy, may produce a histopathological profile similar to a partial mole, which leads to false positivity. Accurate dia-gnosis of a partial hydatidiform mole using molecular genetic methods contributes to the determination of adequate dispensary care for patients.
- Klíčová slova
- Alleles, genotyping techniques, hydatidiform mole, microsatellite repeats,
- MeSH
- aneuploidie MeSH
- lidé MeSH
- mikrosatelitní repetice MeSH
- mola hydatidosa * diagnóza genetika MeSH
- nádory dělohy * diagnóza genetika MeSH
- placenta MeSH
- těhotenství MeSH
- Check Tag
- lidé MeSH
- těhotenství MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
Spliceosomal small nuclear ribonucleoprotein particles (snRNPs) undergo a complex maturation pathway containing multiple steps in the nucleus and in the cytoplasm. snRNP biogenesis is strictly proofread and several quality control checkpoints are placed along the pathway. Here, we analyzed the fate of small nuclear RNAs (snRNAs) that are unable to acquire a ring of Sm proteins. We showed that snRNAs lacking the Sm ring are unstable and accumulate in P-bodies in an LSm1-dependent manner. We further provide evidence that defective snRNAs without the Sm binding site are uridylated at the 3' end and associate with DIS3L2 3'→5' exoribonuclease and LSm proteins. Finally, inhibition of 5'→3' exoribonuclease XRN1 increases association of ΔSm snRNAs with DIS3L2, which indicates competition and compensation between these two degradation enzymes. Together, we provide evidence that defective snRNAs without the Sm ring are uridylated and degraded by alternative pathways involving either DIS3L2 or LSm proteins and XRN1.
- MeSH
- exoribonukleasy metabolismus MeSH
- HeLa buňky MeSH
- konformace nukleové kyseliny * MeSH
- lidé MeSH
- organely metabolismus MeSH
- proteinový komplex SMN metabolismus MeSH
- proteiny vázající RNA metabolismus MeSH
- protoonkogenní proteiny metabolismus MeSH
- RNA malá jaderná chemie metabolismus MeSH
- sekvence nukleotidů MeSH
- stabilita RNA MeSH
- transport RNA * MeSH
- vazba proteinů MeSH
- vazebná místa MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- DIS3L2 protein, human MeSH Prohlížeč
- exoribonukleasy MeSH
- GEMIN5 protein, human MeSH Prohlížeč
- LSM1 protein, human MeSH Prohlížeč
- proteinový komplex SMN MeSH
- proteiny vázající RNA MeSH
- protoonkogenní proteiny MeSH
- RNA malá jaderná MeSH
Uridylation of various cellular RNA species at the 3' end has been generally linked to RNA degradation. In mammals, uridylated pre-let-7 miRNAs and mRNAs are targeted by the 3' to 5' exoribonuclease DIS3L2. Mutations in DIS3L2 have been associated with Perlman syndrome and with Wilms tumor susceptibility. Using in vivo cross-linking and immunoprecipitation (CLIP) method, we discovered the DIS3L2-dependent cytoplasmic uridylome of human cells. We found a broad spectrum of uridylated RNAs including rRNAs, snRNAs, snoRNAs, tRNAs, vault, 7SL, Y RNAs, mRNAs, lncRNAs, and transcripts from pseudogenes. The unifying features of most of these identified RNAs are aberrant processing and the presence of stable secondary structures. Most importantly, we demonstrate that uridylation mediates DIS3L2 degradation of short RNA polymerase II-derived RNAs. Our findings establish the role of DIS3L2 and oligouridylation as the cytoplasmic quality control for highly structured ncRNAs.
- Klíčová slova
- DIS3L2, RNA surveillance, TSSa, ncRNAs, uridylation,
- MeSH
- buněčné linie MeSH
- exoribonukleasy genetika metabolismus MeSH
- imunoprecipitace MeSH
- lidé MeSH
- nekódující RNA metabolismus MeSH
- nukleotidyltransferasy metabolismus MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- DIS3L2 protein, human MeSH Prohlížeč
- exoribonukleasy MeSH
- nekódující RNA MeSH
- nukleotidyltransferasy MeSH
The eukaryotic translation initiation factor 4E is an essential and highly conserved protein. As a part of the translational machinery, it plays a key role in the recruitment of mRNA via binding to its m(7)GpppN 5' terminal cap structure. The opportunistic human pathogen Candida albicans is the only known eukaryotic organism with the ability to survive defects in mRNA capping, which suggests unique features of its eIF4E protein. Here, we provide the first experimental evidence of the function of the C. albicans putative gene orf19.7626 as an eIF4E protein. We also show that Ca4E(Leu116) and Ca4E(Ser116) protein variants, both of which occur naturally in C. albicans due to the ambiguous decoding of the CUG(116) codon, display different sensitivities to elevated temperature. Our results clearly point to the importance of the S4-H4 loop for the function of the Ca4E translation initiation factor, and suggest the possible regulatory role of the codon-reading ambiguity within this loop in C. albicans. We proved Saccharomyces cerevisiae as a useful tool organism for studies of C. albicans translation initiation apparatus.
- MeSH
- Candida albicans genetika růst a vývoj metabolismus účinky záření MeSH
- esenciální geny MeSH
- eukaryotický iniciační faktor 4E metabolismus MeSH
- fungální proteiny metabolismus MeSH
- geny hub MeSH
- kodon * MeSH
- molekulární modely MeSH
- molekulární sekvence - údaje MeSH
- proteosyntéza * MeSH
- sekvence aminokyselin MeSH
- sekvenční homologie MeSH
- sekvenční seřazení MeSH
- substituce aminokyselin genetika MeSH
- teplota MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- eukaryotický iniciační faktor 4E MeSH
- fungální proteiny MeSH
- kodon * MeSH
Hepatitis C virus (HCV) is an important pathogen causing both acute and chronic infections in humans. The HCV polyprotein is synthesized by cap-independent translation initiation after ribosome binding to the highly structured internal ribosome entry site (IRES). The HCV IRES has been shown to have a low requirement for translation initiation factors and the ability to bind directly to the 40S ribosomal subunit. A novel yeast bicistronic reporter system, suitable for sensitive and accurate analysis of IRES activity, has been developed. It employs signal amplification based on the Gal4p transcription factor-mediated activation of a variety of secondary reporter genes. The system has a broad dynamic range and, depending on the nature of the particular secondary reporter, can be used both for precise measurements of IRES activity and for selection and screening for novel IRES variants and IRES trans-acting factors. By using this novel bicistronic system, it was shown that the HCV IRES is functional in yeast cells. Mutational analysis of the IRES loop IV and the adjacent region revealed that, in yeast, as in mammalian cells, translation initiates preferentially at the authentic (342)AUG codon and that disruption of the HCV IRES loop IV abrogates its function, whilst minor positional changes or substitutions of the initiation codon within loop IV are largely tolerated. These findings bring more general insights to translation initiation, but also open the door for utilization of yeast and its sophisticated genetics for searching for new antiviral drugs and HCV IRES trans-acting proteins.
- MeSH
- DNA virů genetika MeSH
- genetické vektory MeSH
- geny hub MeSH
- Hepacivirus genetika patogenita fyziologie MeSH
- kodon iniciační MeSH
- lidé MeSH
- plazmidy genetika MeSH
- proteosyntéza MeSH
- rekombinantní proteiny biosyntéza genetika MeSH
- reportérové geny MeSH
- ribozomy metabolismus MeSH
- Saccharomyces cerevisiae genetika metabolismus MeSH
- sekvence nukleotidů MeSH
- techniky in vitro MeSH
- virové geny MeSH
- virové proteiny biosyntéza genetika MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- DNA virů MeSH
- kodon iniciační MeSH
- rekombinantní proteiny MeSH
- virové proteiny MeSH
IRESite is an exhaustive, manually annotated non-redundant relational database focused on the IRES elements (Internal Ribosome Entry Site) and containing information not available in the primary public databases. IRES elements were originally found in eukaryotic viruses hijacking initiation of translation of their host. Later on, they were also discovered in 5'-untranslated regions of some eukaryotic mRNA molecules. Currently, IRESite presents up to 92 biologically relevant aspects of every experiment, e.g. the nature of an IRES element, its functionality/defectivity, origin, size, sequence, structure, its relative position with respect to surrounding protein coding regions, positive/negative controls used in the experiment, the reporter genes used to monitor IRES activity, the measured reporter protein yields/activities, and references to original publications as well as cross-references to other databases, and also comments from submitters and our curators. Furthermore, the site presents the known similarities to rRNA sequences as well as RNA-protein interactions. Special care is given to the annotation of promoter-like regions. The annotated data in IRESite are bound to mostly complete, full-length mRNA, and whenever possible, accompanied by original plasmid vector sequences. New data can be submitted through the publicly available web-based interface at http://www.iresite.org and are curated by a team of lab-experienced biologists.
- MeSH
- 5' nepřekládaná oblast chemie MeSH
- databáze nukleových kyselin * MeSH
- iniciace translace peptidového řetězce * MeSH
- iniciační faktory metabolismus MeSH
- internet MeSH
- messenger RNA chemie MeSH
- plazmidy chemie MeSH
- promotorové oblasti (genetika) MeSH
- regulační sekvence ribonukleových kyselin MeSH
- RNA virová chemie MeSH
- uživatelské rozhraní počítače MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- 5' nepřekládaná oblast MeSH
- iniciační faktory MeSH
- messenger RNA MeSH
- regulační sekvence ribonukleových kyselin MeSH
- RNA virová MeSH