The secondary structure of nucleic acids containing quartets of guanines, termed G-quadruplexes, is known to regulate the transcription of many genes. Several G-quadruplexes can be formed in the HIV-1 long terminal repeat promoter region and their stabilization results in the inhibition of HIV-1 replication. Here, we identified helquat-based compounds as a new class of anti-HIV-1 inhibitors that inhibit HIV-1 replication at the stage of reverse transcription and provirus expression. Using Taq polymerase stop and FRET melting assays, we have demonstrated their ability to stabilize G-quadruplexes in the HIV-1 long-terminal repeat sequence. Moreover, these compounds were not binding to the general G-rich region, but rather to G-quadruplex-forming regions. Finally, docking and molecular dynamics calculations indicate that the structure of the helquat core greatly affects the binding mode to the individual G-quadruplexes. Our findings can provide useful information for the further rational design of inhibitors targeting G-quadruplexes in HIV-1.
Závěrečná zpráva o řešení grantu Agentury pro zdravotnický výzkum MZ ČR
Nestr.
Amyloidosis is a group of diseases resulting from misfolded protein deposits. Despite better diagnostics and therapy and also covering up in research activities in last decades, examination of patients with suspected disease is not yet straight-forward process. Apart from clinical check-up, a biopsy with proof of deposits is crucial. The subsequent correct amyloid typing is obligate due to disease-bound different attitude to patients and is mainly aimed to antigen-antibody based methods. To avoid frequent non-specific immuno-protein detection, the new methodology based on mass spectrometry seems to be highly specific and sensitive with direct protein recognition in a small amount of tissue. Therefore and in the frame of the proposed project we have decided to improve amyloidosis diagnostics opportunities, to identify new potential proteomic biomarkers and specific fluorescent labels. To facilitate mutual collaboration for the patient benefit and maximise number of analysed samples we have established consortium where four Czech University hospital centres are involved.
Amyloidóza zahrnuje skupinu onemocnění, pro než jsou typická depozita chybně složeného proteinového materiálu v různých tkáních. Stanovení diagnózy není snadné, a to navzdory zlepšení diagnostiky, terapie i zvýšeného zájmu vědců v posledních dekádách. Kromě klinického vyšetření je nezbytná biopsie tkáně s průkazem amyloidu. Přesné určení typu amyloidu je stěžejní pro volbu vhodné strategie péče o pacienta, která se mezi jednotlivými typy nemoci podstatně liší. V současnosti dominují metody založené na reakci antigen-protilátka, avšak nové postupy využívající hmotnostní spektrometrii odstranily rizika spojená s imunologickou detekcí proteinu a jsou vysoce specifické a sensitivní při přímém průkazu proteinu z malého množství tkáně. V tomto kontextu jsme se rozhodli zlepšit možnosti diagnostiky amyloidózy a identifikovat nové potencionální proteomické biomarkery a specifická fluorescenční barviva. Zapojením center při fakultních nemocnicích vznikla pracovní skupina, jejímž cílem je maximalizace počtu vyšetřených vzorků a usnadnění vzájemné spolupráce s výrazným benefitem pro pacienta.
- MeSH
- amyloid chemie MeSH
- amyloidóza diagnostické zobrazování MeSH
- biologické markery chemie MeSH
- fluorescenční barviva analýza MeSH
- imunohistochemie metody MeSH
- lidé MeSH
- optické zobrazování metody MeSH
- proteomika metody MeSH
- Check Tag
- lidé MeSH
- Konspekt
- Patologie. Klinická medicína
- NLK Obory
- vnitřní lékařství
- experimentální medicína
- biochemie
- NLK Publikační typ
- závěrečné zprávy o řešení grantu AZV MZ ČR
It has been more than 50 years since the discovery of dinucleoside polyphosphates (NpnNs) and yet their roles and mechanisms of action remain unclear. Here, we show that both methylated and non-methylated NpnNs serve as RNA caps in Escherichia coli. NpnNs are excellent substrates for T7 and E. coli RNA polymerases (RNAPs) and efficiently initiate transcription. We demonstrate, that the E. coli enzymes RNA 5'-pyrophosphohydrolase (RppH) and bis(5'-nucleosyl)-tetraphosphatase (ApaH) are able to remove the NpnN-caps from RNA. ApaH is able to cleave all NpnN-caps, while RppH is unable to cleave the methylated forms suggesting that the methylation adds an additional layer to RNA stability regulation. Our work introduces a different perspective on the chemical structure of RNA in prokaryotes and on the role of RNA caps. We bring evidence that small molecules, such as NpnNs are incorporated into RNA and may thus influence the cellular metabolism and RNA turnover.
- MeSH
- bakteriální RNA genetika MeSH
- dinukleosidfosfáty genetika MeSH
- DNA řízené RNA-polymerasy genetika MeSH
- Escherichia coli genetika MeSH
- hydrolasy působící na anhydridy kyselin metabolismus MeSH
- konformace nukleové kyseliny MeSH
- metylace MeSH
- proteiny z Escherichia coli metabolismus MeSH
- RNA čepičky genetika MeSH
- stabilita RNA MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
In this study, the pyrrolo[2,1-a]isoquinolines 4a-n were synthesized in good yields in a three steps synthesis from the corresponding α,β-unsaturated esters starting materials. These compounds were tested on six human cancer cells lines to measure the cytotoxic activity as a function of the electronic properties and aromaticity of the substituent at the C-2 position of the pyrroloisoquinoline. Our results reveal that the cytotoxic activity could be explained in terms of the distribution of electronic density across the ring joined to C-2. Also, this study identified 3-hydroxy (4d) and 3-chloro (4j) derivatives with powerful cytotoxic activities. The IC50 values of these compounds were found to be comparable to those of the commercially available Topotecan, Irinotecan, Etoposide, Tamoxifen, and Cisplatin.
- MeSH
- antitumorózní látky chemická syntéza chemie farmakologie MeSH
- cisplatina toxicita MeSH
- isochinoliny chemie farmakologie MeSH
- léky antitumorózní - screeningové testy MeSH
- lidé MeSH
- nádorové buněčné linie MeSH
- proliferace buněk účinky léků MeSH
- pyrroly chemie farmakologie MeSH
- vztahy mezi strukturou a aktivitou MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
Noncovalent molecular interactions between helquats, a new class of dicationic helical extended diquats, and several chiral acidic aromatic drugs and catalysts have been investigated using partial-filling affinity capillary electrophoresis (PF-ACE). Helquats dissolved at 1mM concentration in the aqueous background electrolyte (40mM Tris, 20mM acetic acid, pH 8.1) were introduced as ligand zones of variable length (0-130mm) into the hydroxypropylcellulose coated fused silica capillary whereas 0.1mM solutions of negatively charged chiral drugs or catalysts (warfarin, ibuprofen, mandelic acid, etodolac, binaphthyl phosphate and 11 other acidic aromatic compounds) were applied as a short analyte zone at the injection capillary end. After application of electric field, analyte and ligand migrated against each other and in case of their interactions, migration time of the analyte was increasing with increasing length of the ligand zone. From the tested compounds, only isomers of those exhibiting helical chirality and/or possessing conjugated aromatic systems were enantioselectively separated through their differential interactions with helquats. Some compounds with conjugated aromatic groups interacted with helquats moderately strongly but non-enantiospecifically. Small compounds with single benzene ring exhibited no or very weak non-enantiospecific interactions. PF-ACE method allowed to determine binding constants of the analyte-helquat complexes from the changes of migration times of the analytes. Binding constants of the weakest complexes of the analytes with helquats were less than 50L/mol, whereas binding constants of the strongest complexes were in the range 1 000-1 400L/mol.
Two molecules of mistaken identity are addressed. Uncovering these assignment errors led us to formulate more general guidelines about additional misassignments in cases of published bis-imines derived from 1,2-phenylenediamine and hydroxybenzaldehydes having no substituent in ortho-positions. The main purpose of this article is to highlight this repetitive assignment error in the literature and thus increase the likelihood of correct assignments in future papers.
- MeSH
- DNA chemie MeSH
- G-kvadruplexy * MeSH
- Publikační typ
- časopisecké články MeSH
- komentáře MeSH
- práce podpořená grantem MeSH
