Nicotinamide adenine dinucleotide (NAD) is a critical component of the cellular metabolism and also serves as an alternative 5' cap on various RNAs. However, the function of the NAD RNA cap is still under investigation. We studied NAD capping of RNAs in HIV-1-infected cells because HIV-1 is responsible for the depletion of the NAD/NADH cellular pool and causing intracellular pellagra. By applying the NAD captureSeq protocol to HIV-1-infected and uninfected cells, we revealed that four snRNAs (e.g., U1) and four snoRNAs lost their NAD cap when infected with HIV-1. Here, we provide evidence that the presence of the NAD cap decreases the stability of the U1/HIV-1 pre-mRNA duplex. Additionally, we demonstrate that reducing the quantity of NAD-capped RNA by overexpressing the NAD RNA decapping enzyme DXO results in an increase in HIV-1 infectivity. This suggests that NAD capping is unfavorable for HIV-1 and plays a role in its infectivity.

• MeSH
• HIV infekce * virologie   metabolismus   MeSH
• HIV-1 * MeSH
• lidé MeSH
• malá jadérková RNA * metabolismus   genetika   MeSH
• NAD * metabolismus   MeSH
• RNA čepičky metabolismus   MeSH
• RNA malá jaderná * metabolismus   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

Adhesion G protein-coupled receptors (aGPCRs) play an important role in neurodevelopment, immune defence and cancer; however, their role throughout viral infections is mostly unexplored. We have been searching for specific aGPCRs involved in SARS-CoV-2 infection of mammalian cells. In the present study, we infected human epithelial cell lines derived from lung adenocarcinoma (Calu-3) and colorectal carcinoma (Caco-2) with SARS-CoV-2 in order to analyse changes in the level of mRNA encoding individual aGPCRs at 6 and 12 h post infection. Based on significantly altered mRNA levels, we identified four aGPCR candidates-ADGRB3/BAI3, ADGRD1/GPR133, ADGRG7/GPR128 and ADGRV1/GPR98. Of these receptors, ADGRD1/GPR133 and ADGRG7/GPR128 showed the largest increase in mRNA levels in SARS-CoV-2-infected Calu-3 cells, whereas no increase was observed with heat-inactivated SARS-CoV-2 and virus-cleared conditioned media. Next, using specific siRNA, we downregulated the aGPCR candidates and analysed SARS-CoV-2 entry, replication and infectivity in both cell lines. We observed a significant decrease in the amount of SARS-CoV-2 newly released into the culture media by cells with downregulated ADGRD1/GPR133 and ADGRG7/GPR128. In addition, using a plaque assay, we observed a reduction in SARS-CoV-2 infectivity in Calu-3 cells. In summary, our data suggest that selected aGPCRs might play a role during SARS-CoV-2 infection of mammalian cells.

• MeSH
• adenokarcinom plic * genetika   virologie   patologie   metabolismus   MeSH
• Caco-2 buňky MeSH
• COVID-19 * genetika   virologie   metabolismus   MeSH
• lidé MeSH
• messenger RNA * genetika   metabolismus   MeSH
• nádorové buněčné linie MeSH
• nádory plic genetika   virologie   patologie   metabolismus   MeSH
• receptory spřažené s G-proteiny * metabolismus   genetika   MeSH
• SARS-CoV-2 * genetika   fyziologie   metabolismus   MeSH
• upregulace * genetika   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

The mechanism of action of various viruses has been the primary focus of many studies. Yet, the data on RNA modifications in any type of virus are scarce. Methods for the sensitive analysis of RNA modifications have been developed only recently and they have not been applied to viruses. In particular, the RNA composition of HIV-1 virions has never been determined with sufficiently exact methods. Here, we reveal that the RNA of HIV-1 virions contains surprisingly high amount of the 1-methyladenosine. We are the first to use a liquid chromatography-mass spectrometry analysis (LC/MS) of virion RNA, which we combined with m1A profiling and deep sequencing. We found that m1A was present in the tRNA, but not in the genomic HIV-1 RNA and the abundant 7SL RNA. We were able to calculate that an HIV-1 virion contains per 2 copies of genomic RNA and 14 copies of 7SL RNA also 770 copies of tRNA, which is approximately 10 times more than thus far expected. These new insights into the composition of the HIV-1 virion can help in future studies to identify the role of nonprimer tRNAs in retroviruses. Moreover, we present a promising new tool for studying the compositions of virions.

• MeSH
• adenosin analogy a deriváty   metabolismus   MeSH
• chromatografie kapalinová metody   MeSH
• genom virový genetika   MeSH
• HIV-1 genetika   fyziologie   MeSH
• hmotnostní spektrometrie metody   MeSH
• lidé MeSH
• nádorové buněčné linie MeSH
• RNA malá cytoplazmatická genetika   MeSH
• RNA transferová genetika   metabolismus   MeSH
• RNA virová genetika   metabolismus   MeSH
• sekvence nukleotidů MeSH
• sestavení viru genetika   MeSH
• signál-rozpoznávající částice genetika   MeSH
• virion genetika   metabolismus   MeSH
• vysoce účinné nukleotidové sekvenování metody   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Cancer-associated fibroblasts (CAFs) significantly influence biological properties of many tumors. The role of these mesenchymal cells is also anticipated in human gliomas. To evaluate the putative role of CAFs in glioblastoma, we tested the effect of CAF conditioned media on the proliferation and chemotaxis of glioma cells. The proliferation of glioma cells was stimulated to similar extent by both the normal fibroblasts (NFs) and CAF-conditioned media. Nevertheless, CAF-conditioned media enhanced the chemotactic migration of glioma cells significantly more potently than the media from normal fibroblasts. In order to determine whether CAF-like cells are present in human glioblastomas, immunofluorescence staining was performed on tissue samples from 20 patients using markers typical for CAFs. This analysis revealed regular presence of mesenchymal cells expressing characteristic CAF markers α-smooth muscle actin and TE-7 in human glioblastomas. These observations indicate the potential role of CAF-like cells in glioblastoma biology.

• MeSH
• aktiny biosyntéza   MeSH
• fibroblasty patologie   MeSH
• glioblastom genetika   patologie   MeSH
• kultivační média speciální * MeSH
• lidé MeSH
• nádorové buněčné linie MeSH
• nádorové mikroprostředí genetika   MeSH
• pohyb buněk * MeSH
• proliferace buněk genetika   MeSH
• regulace genové exprese u nádorů MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Malignant gliomas exhibit abnormal expression of proteolytic enzymes that may participate in the uncontrolled cell proliferation and aberrant interactions with the brain extracellular matrix. The multifunctional membrane bound serine aminopeptidase dipeptidyl peptidase (DPP)-IV has been linked to the development and progression of several malignancies, possibly both through the enzymatic and nonenzymatic mechanisms. In this report we demonstrate the expression of DPP-IV and homologous proteases fibroblast activation protein, DPP8 and DPP9 in primary cell cultures derived from high-grade gliomas, and show that the DPP-IV-like enzymatic activity is negatively associated with their in vitro growth. More importantly, the DPP-IV positive subpopulation isolated from the primary cell cultures using immunomagnetic separation exhibited slower proliferation. Forced expression of the wild as well as the enzymatically inactive mutant DPP-IV in glioma cell lines resulted in their reduced growth, migration and adhesion in vitro, as well as suppressed glioma growth in an orthotopic xenotransplantation mouse model. Microarray analysis of glioma cells with forced DPP-IV expression revealed differential expression of several candidate genes not linked to the tumor suppressive effects of DPP-IV in previous studies. Gene set enrichment analysis of the differentially expressed genes showed overrepresentation of gene ontology terms associated with cell proliferation, cell adhesion and migration. In conclusion, our data show that DPP-IV may interfere with several aspects of the malignant phenotype of glioma cells in great part independent of its enzymatic activity.

• MeSH
• buněčná adheze MeSH
• buněčný cyklus MeSH
• dipeptidasy genetika   metabolismus   MeSH
• dipeptidylpeptidasa 4 genetika   metabolismus   MeSH
• dipeptidylpeptidasy a tripeptidylpeptidasy genetika   metabolismus   MeSH
• gliom enzymologie   genetika   MeSH
• imunomagnetická separace MeSH
• lidé MeSH
• mutace MeSH
• myši MeSH
• nádorové buňky kultivované MeSH
• pohyb buněk MeSH
• primární buněčná kultura MeSH
• proliferace buněk MeSH
• regulace genové exprese u nádorů MeSH
• signální transdukce genetika   MeSH
• stanovení celkové genové exprese MeSH
• transfekce MeSH
• xenogenní modely - testy protinádorové aktivity MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Imaging methods based on light detection are being increasingly used for the non-invasive assessment of tumour growth in animal models. In contrast with bioluminescence imaging, there are no studies assessing the use of macroscopic fluorescence imaging for the longitudinal monitoring of tumour growth in an orthotopic glioma mouse model. Glioma cells expressing the red-shifted fluorescent protein mKate2 were orthotopically implanted to NOD-rag mice and the tumour size estimated by macroscopic fluorescence imaging was compared to the tumour volume determined morphometrically. There was no significant correlation between the data obtained by non-invasive macroscopic fluorescence imaging and post mortem morphometry. In addition, the fluorescence imaging failed to detect a morphometrically verified difference in tumour volume between animals with tumours expressing a potential tumour suppressor gene and controls. The fluorescence signal was affected by the spatial pattern of tumour growth and substantially attenuated by the interfering brain tissue. Our results indicate that the fluorescence signal emitted by glioma cells reflected not only the tumour mass, but also its spatial distribution. Macroscopic planar FLI in an epi-illumination mode and a conventional source of excitation light therefore appears to be more suitable for semi-quantitative assessment of the tumour growth especially in the case of superficially located tumours rather than for precise volume estimation of the xenografts located deep within the brain tissue.

• MeSH
• diagnostické zobrazování metody   metody   MeSH
• fluorescence MeSH
• gliom diagnóza   MeSH
• lidé MeSH
• modely nemocí na zvířatech MeSH
• myši MeSH
• nádorové buněčné linie MeSH
• optická tomografie metody   MeSH
• transplantace nádorů MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• práce podpořená grantem MeSH