Bacteria have evolved structured RNAs that can associate with RNA polymerase (RNAP). Two of them have been known so far-6S RNA and Ms1 RNA but it is unclear if any other types of RNAs binding to RNAP exist in bacteria. To identify all RNAs interacting with RNAP and the primary σ factors, we have established and performed native RIP-seq in Bacillus subtilis, Corynebacterium glutamicum, Streptomyces coelicolor, Mycobacterium smegmatis and the pathogenic Mycobacterium tuberculosis. Besides known 6S RNAs in B. subtilis and Ms1 in M. smegmatis, we detected MTS2823, a homologue of Ms1, on RNAP in M. tuberculosis. In C. glutamicum, we discovered novel types of structured RNAs that associate with RNAP. Furthermore, we identified other species-specific RNAs including full-length mRNAs, revealing a previously unknown landscape of RNAs interacting with the bacterial transcription machinery.
- MeSH
- Bacillus subtilis genetika metabolismus MeSH
- bakteriální proteiny * metabolismus genetika MeSH
- bakteriální RNA * metabolismus genetika MeSH
- Corynebacterium glutamicum genetika metabolismus MeSH
- DNA řízené RNA-polymerasy * metabolismus genetika MeSH
- genetická transkripce MeSH
- konformace nukleové kyseliny MeSH
- Mycobacterium smegmatis genetika metabolismus enzymologie MeSH
- Mycobacterium tuberculosis genetika metabolismus MeSH
- nekódující RNA MeSH
- regulace genové exprese u bakterií MeSH
- sigma faktor * metabolismus genetika MeSH
- Streptomyces coelicolor genetika metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Activating transcription factor 4 (ATF4) is a master transcriptional regulator of the integrated stress response, leading cells toward adaptation or death. ATF4's induction under stress was thought to be due to delayed translation reinitiation, where the reinitiation-permissive upstream open reading frame 1 (uORF1) plays a key role. Accumulating evidence challenging this mechanism as the sole source of ATF4 translation control prompted us to investigate additional regulatory routes. We identified a highly conserved stem-loop in the uORF2/ATF4 overlap, immediately preceded by a near-cognate CUG, which introduces another layer of regulation in the form of ribosome queuing. These elements explain how the inhibitory uORF2 can be translated under stress, confirming prior observations but contradicting the original regulatory model. We also identified two highly conserved, potentially modified adenines performing antagonistic roles. Finally, we demonstrated that the canonical ATF4 translation start site is substantially leaky scanned. Thus, ATF4's translational control is more complex than originally described, underpinning its key role in diverse biological processes.
- MeSH
- fyziologický stres MeSH
- HEK293 buňky MeSH
- lidé MeSH
- otevřené čtecí rámce * genetika MeSH
- proteosyntéza * MeSH
- ribozomy * metabolismus MeSH
- sekvence nukleotidů MeSH
- transkripční faktor ATF4 * metabolismus genetika MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Surgical treatment of cervical cancer has undergone many changes over the last decades. Through simple operations and subsequent surgical radicality to the gradual transformation to personalized medicine. In this article, we try to retrospectively evaluate the development of surgical treatment of malignant neoplasms of the cervix from the beginnings of surgery to the present.
- MeSH
- gynekologické chirurgické výkony dějiny metody MeSH
- lidé MeSH
- nádory děložního čípku * chirurgie MeSH
- Check Tag
- lidé MeSH
- ženské pohlaví MeSH
- Publikační typ
- přehledy MeSH
Bacteria employ small non-coding RNAs (sRNAs) to regulate gene expression. Ms1 is an sRNA that binds to the RNA polymerase (RNAP) core and affects the intracellular level of this essential enzyme. Ms1 is structurally related to 6S RNA that binds to a different form of RNAP, the holoenzyme bearing the primary sigma factor. 6S RNAs are widespread in the bacterial kingdom except for the industrially and medicinally important Actinobacteria. While Ms1 RNA was identified in Mycobacterium, it is not clear whether Ms1 RNA is present also in other Actinobacteria species. Here, using a computational search based on secondary structure similarities combined with a linguistic gene synteny approach, we identified Ms1 RNA in Streptomyces. In S. coelicolor, Ms1 RNA overlaps with the previously annotated scr3559 sRNA with an unknown function. We experimentally confirmed that Ms1 RNA/scr3559 associates with the RNAP core without the primary sigma factor HrdB in vivo. Subsequently, we applied the computational approach to other Actinobacteria and identified Ms1 RNA candidates in 824 Actinobacteria species, revealing Ms1 RNA as a widespread class of RNAP binding sRNAs, and demonstrating the ability of our multifactorial computational approach to identify weakly conserved sRNAs in evolutionarily distant genomes.
- Publikační typ
- časopisecké články MeSH
In Morocco, leishmaniases are a major public health problem due to their genetic diversity and geographical distribution. Cutaneous leishmaniasis (CL) is an infectious disease caused by various species of Leishmania and transmitted typically by bite of phlebotomine sand flies. This study identifies sand fly fauna in Ibaraghen village, province of Azilal, which is a focus of CL, by combination of morphological and molecular methods (sequencing of COI gene, MALDI-TOF MS protein profiling). Nested-kDNA PCR was used to detect and identify Leishmania species within potential vector species. 432 CDC light traps were placed at different heights above ground level at four capture sites during a whole year. Traps at 1.5 m above the ground yielded capture of sand flies almost double compared to above ground level (29.33%), while the collection reached 55.09% when the traps were placed 2.5 m above ground. A total of 2,830 sand flies were collected, 2,213 unfed specimens were morphologically identified, 990 males (44.73%) and 1,223 females (55.26%) of 13 species; ten Phlebotomus species and three Sergentomyia species. Six species were analysed by MALDI-TOF MS protein profiling (4 Phlebotomus and 2 Sergentomiya species), and their identification was confirmed by COI sequencing. 1,375 unfed females were screened for the presence of Leishmania by nested-kDNA PCR in pools, 11/30 pools of P. sergenti showing a single band of 750 bp corresponding to L. tropica. Our results confirm the role of P. sergenti as a proven vector in Azilal focus of cutaneous leishmaniasis; however, the relative abundance of other species known as vectors of Leishmania species emphasizes the risk of introduction of L. infantum and L. major in this province. For the first time in Morocco, a combined approach to identify sand flies by both morphology and molecular methods based on DNA barcoding and MALDI-TOF MS protein profiling was applied.
- MeSH
- hmyz - vektory MeSH
- kinetoplastová DNA MeSH
- Leishmania * genetika MeSH
- leishmanióza kožní * epidemiologie veterinární MeSH
- Phlebotomus * MeSH
- Psychodidae * MeSH
- spektrometrie hmotnostní - ionizace laserem za účasti matrice veterinární MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Maroko MeSH
BACKGROUND: Sand flies are principal vectors of the protozoan parasites Leishmania spp. and are widely distributed in all warmer regions of the world, including the Mediterranean parts of Europe. In Central European countries, the sand fly fauna is still under investigation. Phlebotomus mascittii, a suspected but unproven vector of Leishmania infantum, is regarded as the most widely distributed species in Europe. However, many aspects of its biology and ecology remain poorly known. The aim of this study was to provide new data on the biology and ecology of Ph. mascittii in Austria to better understand its current distribution and potential dispersal. METHODS: Sand flies were collected by CDC light traps at four localities in Austria for 11 (2018) and 15 weeks (2019) during the active sand fly season. Climatic parameters (temperature, relative humidity, barometric pressure and wind speed) were retrospectively obtained for the trapping periods. Sand flies were identified by a combined approach (morphology, DNA barcoding, MALDI-TOF protein profiling), and blood meals of engorged females were analysed by DNA sequencing and MALDI-TOF mass spectrometry. RESULTS: In total, 450 individuals of Ph. mascittii were caught. Activity was observed to start at the beginning of June and end at the end of August with peaks in mid-July at three locations and early August at one location. Increased activity was associated with relatively high temperatures and humidity. Also, more individuals were caught on nights with low barometric pressure. Analysis of five identified blood meals revealed chicken (Gallus gallus) and equine (Equus spp.) hosts. Sand fly abundance was generally associated with availability of hosts. CONCLUSION: This study reports unexpectedly high numbers of Ph. mascittii at selected Austrian localities and provides the first detailed analysis of its ecology to date. Temperature and humidity were shown to be good predictors for sand fly activity. Blood meal analyses support the assumption that Ph. mascittii feeds on mammals as well as birds. The study significantly contributes to understanding the ecology of this sand fly species in Central Europe and facilitates prospective entomological surveys.
- MeSH
- ekologie * MeSH
- hmyz - vektory * parazitologie MeSH
- koně MeSH
- kur domácí MeSH
- Leishmania infantum MeSH
- Phlebotomus * genetika MeSH
- Psychodidae MeSH
- retrospektivní studie MeSH
- roční období * MeSH
- sekvenční analýza DNA MeSH
- spektrometrie hmotnostní - ionizace laserem za účasti matrice MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Evropa MeSH
- Rakousko MeSH
Laccase is predominantly found in lignin degrading filamentous white rot fungi, where it is involved in the oxidative degradation of this recalcitrant heteropolymer. In brown rot fungi it is much less prevalent: laccases from only a few brown rots have been detected and only two have been characterized. This study tries to understand the role of this ligninolytic enzyme in brown rots by investigating the catalytic properties of laccases secreted by Fomitopsis pinicola FP58527 SS1. When grown on either poplar or spruce wood blocks, several laccases were detected in the secretome. Two of them (FpLcc1 and FpLcc2) were heterologously produced using Trichoderma reesei QM9414 Δxyr1 as expression host and purified to homogeneity by consecutive steps of hydrophobic interaction, anion exchange and size exclusion chromatography. With the substrates 2,2-azino-bis(3-ethylthiazoline-6-sulfonate) (ABTS), 2,6-dimethoxyphenol (2,6-DMP) and guaiacol both laccases showed similar, low pH-optima below 3 for ABTS and 2,6-DMP and at pH 3.5 for guaiacol which is at the acidic end of laccases isolated from white rot fungi. The determined KM values were low while kcat values measured at acidic conditions were comparable to those reported for other laccases from white rot fungi. While both enzymes showed a moderate decrease in activity in the presence of oxalic and citric acid FpLcc2 was activated by acetic acid up to 3.7 times. This activation effect is much more pronounced at pH 5.0 compared to pH 3.0 and could already be observed at a concentration of 1 mM acetic acid.
- MeSH
- Coriolaceae * genetika MeSH
- Hypocreales MeSH
- lakasa * genetika MeSH
- lignin MeSH
- Publikační typ
- časopisecké články MeSH
Photochemical energy conversion during oxygenic photosynthesis is performed by membrane-embedded chlorophyll-binding protein complexes. The biogenesis and maintenance of these complexes requires auxiliary protein factors that optimize the assembly process and protect nascent complexes from photodamage. In cyanobacteria, several lipoproteins contribute to the biogenesis and function of the photosystem II (PSII) complex. They include CyanoP, CyanoQ, and Psb27, which are all attached to the lumenal side of PSII complexes. Here, we show that the lumenal Ycf48 assembly factor found in the cyanobacterium Synechocystis sp. PCC 6803 is also a lipoprotein. Detailed mass spectrometric analysis of the isolated protein supported by site-directed mutagenesis experiments indicates lipidation of the N-terminal C29 residue of Ycf48 and removal of three amino acids from the C-terminus. The lipobox sequence in Ycf48 contains a cysteine residue at the -3 position compared to Leu/Val/Ile residues found in the canonical lipobox sequence. The atypical Ycf48 lipobox sequence is present in most cyanobacteria but is absent in eukaryotes. A possible role for lipoproteins in the coordinated assembly of cyanobacterial PSII is discussed.
RNA synthesis is central to life, and RNA polymerase (RNAP) depends on accessory factors for recovery from stalled states and adaptation to environmental changes. Here, we investigated the mechanism by which a helicase-like factor HelD recycles RNAP. We report a cryo-EM structure of a complex between the Mycobacterium smegmatis RNAP and HelD. The crescent-shaped HelD simultaneously penetrates deep into two RNAP channels that are responsible for nucleic acids binding and substrate delivery to the active site, thereby locking RNAP in an inactive state. We show that HelD prevents non-specific interactions between RNAP and DNA and dissociates stalled transcription elongation complexes. The liberated RNAP can either stay dormant, sequestered by HelD, or upon HelD release, restart transcription. Our results provide insights into the architecture and regulation of the highly medically-relevant mycobacterial transcription machinery and define HelD as a clearing factor that releases RNAP from nonfunctional complexes with nucleic acids.
- MeSH
- bakteriální proteiny chemie metabolismus ultrastruktura MeSH
- DNA bakterií chemie metabolismus MeSH
- DNA řízené RNA-polymerasy chemie metabolismus ultrastruktura MeSH
- elektronová kryomikroskopie MeSH
- katalytická doména MeSH
- molekulární modely MeSH
- Mycobacterium smegmatis enzymologie MeSH
- nukleové kyseliny metabolismus MeSH
- proteinové domény MeSH
- vazba proteinů MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, N.I.H., Extramural MeSH
Sand flies (Diptera: Psychodidae: Phlebotominae) are blood-feeding insects that transmit the protozoan parasites Leishmania spp. and various arthropod-borne (arbo) viruses. While in Mediterranean parts of Europe the sand fly fauna is diverse, in Central European countries including Austria mainly Phlebotomus mascittii is found, an assumed but unproven vector of Leishmania infantum. To update the currently understudied sand fly distribution in Austria, a sand fly survey was performed and other entomological catches were screened for sand flies. Seven new trapping locations of Ph. mascittii are reported including the first record in Vienna, representing also one of the first findings of this species in a city. Morphological identification, supported by fluorescence microscopy, was confirmed by two molecular approaches, including sequencing and matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS) protein profiling. Sand fly occurrence and activity were evaluated based on surveyed locations, habitat requirements and climatic parameters. Moreover, a first comparison of European Ph. mascittii populations was made by two marker genes, cytochrome c oxidase subunit 1 (COI), and cytochrome b (cytb), as well as MALDI-TOF mass spectra. Our study provides new important records of Ph. mascittii in Austria and valuable data for prospective entomological surveys. MALDI-TOF MS protein profiling was shown to be a reliable tool for differentiation between sand fly species. Rising temperatures and globalization demand for regular entomological surveys to monitor changes in species distribution and composition. This is also important with respect to the possible vector competence of Ph. mascittii.
- Publikační typ
- časopisecké články MeSH
